February 2008

Did a meteor over central Italy in AD 312 change the course of Roman and Christian history? 

Dr David Whitehouse
BBC
Mon, 23 Jun 2003 14:57 EDT

A team of geologists believes it has found the incoming space rock's impact crater, and dating suggests its formation coincided with the celestial vision said to have converted a future Roman emperor to Christianity.

It was just before a decisive battle for control of Rome and the empire that Constantine saw a blazing light cross the sky and attributed his subsequent victory to divine help from a Christian God.

©Unknown

Constantine went on to consolidate his grip on power and ordered that persecution of Christians cease and their religion receive official status.

Civil war

In the fourth century AD, the fragmented Roman Empire was being further torn apart by civil war. Constantine and Maxentius were bitterly fighting to be the sole emperor.

Constantine was the son of the western emperor Constantius Chlorus. When he died in 306, his father's troops proclaimed Constantine emperor.

" ...a most marvellous sign appeared to him from heaven... " Eusebius

But in Rome, the favourite was Maxentius, son of Constantius' predecessor, Maximian.

With both men claiming the title, a conference was called in AD 308 that resulted in Maxentius being named as senior emperor along with Galerius, his father-in-law. Constantine was to be a Caesar, or junior emperor.

The situation was not a stable one, however, and by 312 the two men were at war.

Constantine overran Italy and faced Maxentius at the Milvian Bridge over the Tiber a few kilometres from Rome. Both knew it would be a decisive battle with Constantine's forces outnumbered.

'Conquer by this'

It was then that something strange happened. Eusebius - one of the Christian Church's early historians - relates the event in his Conversion of Constantine.

"...while he was thus praying with fervent entreaty, a most marvellous sign appeared to him from heaven, the account of which it might have been hard to believe had it been related by any other person.

"...about noon, when the day was already beginning to decline, he saw with his own eyes the trophy of a cross of light in the heavens, above the Sun, and bearing the inscription 'conquer by this'.

"At this sight he himself was struck with amazement, and his whole army also, which followed him on this expedition, and witnessed the miracle."

Spurred on by divine intervention, Constantine's army won the day and he gave homage to the God of the Christians whom he believed had helped him.

©Unknown

This was a time when Christianity was struggling. Support from the most powerful man in the empire allowed the emerging religious movement to flourish.

Like a nuclear blast

But what was the celestial event that converted Constantine and altered the course of history?

Jens Ormo, a Swedish geologist, and colleagues working in Italy believe Constantine witnessed a meteoroid impact.

Crater, Ormo The research team believes it has identified what remains of the impactor's crater.

It is the small, circular Cratere del Sirente in central Italy. It is clearly an impact crater, Ormo says, because its shape fits and it is also surrounded by numerous smaller, secondary craters, gouged out by ejected debris, as expected from impact models.

Radiocarbon dating puts the crater's formation at about the right time to have been witnessed by Constantine and there are magnetic anomalies detected around the secondary craters - possibly due to magnetic fragments from the meteorite.

According to Ormo, it would have struck the Earth with the force of a small nuclear bomb, perhaps a kiloton in yield. It would have looked like a nuclear blast, with a mushroom cloud and shockwaves.

It would have been quite an impressive sight and, if it really was what Constantine saw, could have turned the tide of the conflict.

But what would have happened if this chance event - perhaps as rare as once every few thousand years - had not occurred in Italy at that time?

Maxentius might have won the battle. Roman history would have been different and the struggling Christians might not have received state patronage.

The history of Christianity and the establishment of the popes in Rome might have been very different.

Daytime meteor startles West Texans 

Associated Press
Fri, 10 Oct 1997 15:03 EDT

It wasn't the end of the world. It just looked like it to those people who saw a cosmic fireworks show over Southwest skies.

A midday meteor streaking above West Texas and New Mexico on Thursday sent residents scurrying to their phones to report what many feared was an airplane exploding or some kind of aerial collision.

©CNN

Satellite image of meteor

Robert Simpson saw it from his home near Fort Davis and was delighted. But then, he had a better idea of what it was.

"It always kind of floors you," said Simpson, a spokesman for McDonald Observatory, 175 miles southeast of El Paso.

The meteor appeared at 12:47 p.m. as a flash about as bright as the surface of a setting sun, he said.

The reports -- of the light, an explosive blast and a smoke trail -- are all consistent with the appearance of a daytime meteor, also known as a fireball or bolide.

"If it had happened at night it would have lit up the countryside as bright as day," said Bill Wren, another observatory spokesman.

As it was, it was pretty spectacular.

Fire and police agencies in El Paso County and southern New Mexico were flooded with reports of an explosion that shook homes and jangled nerves.

A police helicopter flying about 25 miles east of the city spotted about an acre of scorched ranch land, and authorities believe it could be where the meteor hit. But the foreman of Cooper Cattle Co. ranch said he didn't think so.

"We had two different fires out here a couple of days ago during the lightning storms," said Dub Pruitt.

Some residents saw the flash; others heard only a shuddering boom.

"It shook the whole damned neighborhood," said Tom Tyra, a Horizon City resident. "Everybody came out of their house."

Korean Polar Explorers Find Massive Meteorite 

Chosun
Tue, 15 Jan 2008 16:16 EST

A team of Korean scientists in Antarctica has discovered a large meteorite weighing 3.7 kg.

The Korea Polar Research Institute under the Korea Ocean Research and Development Institute said Monday that the country's second exploration team to Antarctica discovered 13 meteorites in the western Thiel Mountains on Dec. 24, 29 and 30.

Last year, the country's first exploration team to the southern continent found five meteorites, but they weighed only between 200 and 400 g.

Meteorites, large pieces of rocks from outer space that have landed on Earth, are important in the study of the creation of the solar system and the evolution of the planets.

Antarctica accounts for just three percent of the Earth's surface, but over 80 percent or 25,000 of all discovered meteorites have been found there.

With a total of 18 meteorites discovered by the two exploration teams, Korea has become the fifth holder of meteorites after the U.S., Japan, China and Italy.

Fluoridated Water: Ancient meteorite causing modern problems 

Randy Boswell
Canwest News Service
Sat, 02 Feb 2008 16:21 EST

A space rock that smashed into Canada more than 200 million years ago is being blamed for health risks faced today by several communities in central Manitoba, according to a new international study of groundwater quality around the ancient Lake St. Martin meteorite crater north of Winnipeg.

In what's being described as the first-ever finding of a modern-day health threat posed by a prehistoric meteorite strike, the researchers say elevated levels of fluoride and other chemicals in the area's groundwater can be traced to the shattering of subsurface granite when the extraterrestrial object slammed into Earth nearly a quarter of a billion years ago.

©Google Maps

An aerial view of Lake St. Martin, Manitoba.

"The possibility that a meteor impact could devastate modern human civilization is a real concern," especially given such events as the dinosaur-killing strike on the Yucatan Peninsula 65 million years ago, the researchers note in their study of the Lake St. Martin crater in central Manitoba, published in the February issue of Geology.

"However, meteors may affect human populations through more subtle routes in addition to these commonly recognized, catastrophic events."

Located between Lake Manitoba and Lake Winnipeg about 250 north of Winnipeg, Lake St. Martin is believed to be the site of a meteorite strike about 230 million years ago that left a 24-kilometre-wide crater, now largely obscured by time.

Scientists recently theorized that the Manitoba site has sister craters in France, Quebec, North Dakota and Russia - all created within hours of each other when large pieces of a fragmented meteor struck Earth.

For years, Canadian scientists have been trying to understand the cause of poor water quality in the town of Gypsumville and two nearby First Nations communities around Lake St. Martin. High levels of fluoride, well beyond recommended health limits, have forced area residents to seek alternative water supplies.

The new study - led by New Zealand-based geoscientist Matt Leybourne and two of his former colleagues at the Geological Survey of Canada - shows how shocked, fractured and melted rocks around the ancient impact site allow fluoride to leach more easily into the area's groundwater. Nearby rocks beyond the crater don't show the same leaching effect.

"It's a smoking gun that's been smoking for a long time," Ottawa-based scientist Jan Peter, co-author of the study, told Canwest News Service. "We don't know of anybody else who's made that kind of a link."

Elevated fluoride is "a major health issue in many parts of the world" that can cause damage to teeth, softening of bones, calcified tendons and ligaments and neurological damage, the study states.

Peter said the communities around Lake St. Martin have long been aware of the groundwater contamination, but now have a clearer explanation - reaching back to the Triassic age - of when the problem began.

He added: "The best guesstimate is that the meteorite strike was around 230 million years ago. That's a heck of a long time to still be having its impact felt."

A rain of around 70 tons of iron

George Zay
Sky Publishing Corporation
Mon, 12 Feb 1990 15:17 EST

February 12, 1947

This week marks the golden anniversary of what is arguably the most spectacular meteorite fall ever seen. At 10:40 a.m. on February 12, 1947, a incredibly bright fireball seared its way across the sky of eastern Siberia and rained around 70 tons of iron meteorites onto the rugged landscape. Because it was so well documented, the Sikhote-Alin fall proved a great boon to meteorite science.

The 1947 Siberian event is considered in most literature as one of the two most significant events this century where the earth has encountered objects from space. It was an iron meteorite that broke up only about 5 miles above the earth. It produced over 100 craters with the largest being around 85 feet in diameter. The strewnfield covered an area of about 1 mile by a half mile. There were no fires or similar destruction like that found at Tunguska.

Shredded trees and broken branches mostly. A total of 23 tons of meteorites were recovered and it's been estimated it's total mass was around 70 tons when it broke up.

More students find asteroids

David A. Vallette
The Republican
Sun, 03 Feb 2008 05:27 EST

Gill - If the name "2007TK238" rings no bells, that would not be surprising.

What is surprising, however, is that it was students here at Northfield Mount Hermon School, not some established astronomer, who discovered an asteroid subsequently identified with that number-filled name.

A trio of students in S. Hughes Pack's astronomy class, and Pack himself, got official credit for discovering a group of asteroids while working with the Center for Astrophysics in Cambridge. They used images fed to their computers from a 32-inch telescope in Illinois.

The class pored over the images, primarily to give position reports on asteroids that were already discovered, thereby enabling the center to keep tabs on where the potentially lethal bodies were traveling, and if they were a threat to Earth.

But the students, Wida Li from China, Josh R. Throckmorton from Bedford, and Chelsea A. Bunker of South Deerfield, came up with some blurry, small objects that weren't on anybody's list, and determined they were previously unknown asteroids, which are rocks left over from the creation of the solar system. Their finding was investigated and confirmed by the center.

"Being able to step into the shoes of a professional astronomer, and actually contribute to the world of science, is one of the coolest things I have ever done," said Throckmorton.

And fortunately, the asteroids the students discovered are not headed this way.

"We don't want to be the ones to find the asteroid that hits Earth," Pack said.

Pack, in his classes, tries to impress upon the students the enormity of the consequences should a large asteroid hit Earth, citing it was an event that already happened, wiping out whole species of life. He shows them Hollywood's "Armageddon," in which Bruce Willis leads an expedition of miners to land on an oncoming asteroid to successfully blow it up, a film full of scientific absurdities but which gets the attention of students, he said.

There is little that could actually be done to deter an asteroid, and only with knowing its exact course could an impact area be evacuated, he said, to try to save some lives.

For Pack, as the teacher, the process is the thing.

"These are high school students doing real science. It is not easy and it is mundane - that's what real science is," he said.

Despite the tedium of the asteroid location and positioning work, the students found it thrilling.

"It was really fun, actually," said Bunker.

"It's good to know we are making a contribution while not even into college yet," Throckmorton said.

A Large Ball of Fire 

Freddy Cuevas
Associated Press
Sun, 15 Dec 1996 15:19 EST

A meteorite slammed into a sparsely populated area of Honduras last month, terrifying residents and leaving a 165-foot-wide crater, scientists confirmed Sunday.

Villagers reported seeing a fireball crash and break into small red and yellow pieces on Nov. 22 near San Luis, in the western province of Santa Barbara. But Sunday's statement was the first official word that the object was a meteorite.

Maria Cristina Pineda, a physicist from the National Autonomous University of Honduras, said Sunday that the meteorite was composed of materials that were 4 billion years old, Pineda said.

There was no word on the dimensions of the meteorite, but it was much smaller than the size of the crater. Some 50,000 years ago, a meteorite 180 feet wide smashed into northern Arizona and dug a crater 4,000 feet wide. And a 300-foot meteorite struck in Siberia in 1908, leveling trees for miles.

Residents of San Luis, 125 miles west of the capital, were terrified by the meteorite's crash, which sparked a fire that destroyed several acres of coffee plants and damaged a main highway.

"We saw a large ball of fire, with a long tail that rapidly descended from the sky and fell near San Luis, before our incredulous eyes," said Elmer Adan Rivera, a teacher from the region.

"I arrived almost immediately to the site of the explosion," said peasant Francisco Aguilar Sabillon. "There were enormous flames, and everything was destroyed. Because of that I fled from the place, frightened."

Authorities have asked those living nearby to stay away from the crash site. The meteorite did not appear to have any properties that would pose a threat to humans, they said.

Unsolved Case: A show of gold 

Jim Cummings
Santa Fe Fireball
Fri, 04 Oct 1996 15:21 EDT

Part 1: A show of gold

Thursday Oct 3, 8:00pm Saw what appeared to be a low-altitude fireball, heading north from the plains, into the southern end of the Sangre de Cristos, just southeast of Santa Fe.

When I first saw it, it was in full glory; I don't know how much I missed. It burned brilliant green, with active, changing head and tail, for several (3-6) seconds, then disintegrated in a show of gold, into 4 or 5 smaller pieces, glowing white, spread out in a line, until they seemed to burn out, another 3-5 seconds later.

Distance is of course unknown, to me it seemed that the final shards were not far over the foothills. It seemed to be travelling as fast as a low flying airplane.

Looking for another viewer, to help confirm position and height. Any one else happen to see it?

It was surely the most thrilling 10 seconds of my five years of amateur viewing!

Part 2: A bird? A plane?

A brilliant meteor seen in the skies of the western U.S. on the evening of October 3 was likely a piece of an asteroid or comet, or even a piece of space junk, astronomers said.

The meteor was seen from California to New Mexico at around 9pm PDT (4am GMT October 4). It was described by many as a long green streak bright enough to light up sky for several seconds. Hundreds of people contacted local authorities, believing the streak to be the result of a mid-air plane accident. The flash, however, took place too high to be possibly caused by a plane.

John Mosley, an astronomer at the Griffith Park Observatory in Los Angeles, attributed the flash to a chunk of comet or asteroid material that burned up in the Earth's atmosphere. JPL officials added the possibility that the meteor was a piece of space junk reentering the Earth's atmosphere. No debris from the meteor was found on the ground.

Part 3: A reward of 5000 $

The University of California at Los Angeles (UCLA) offers a reward of 5.000 $ for a piece weighing 100 g or more of the meteorite fallen on October 3, 1996. Some scientists say that the bolide bounced in the upper atmosphere. Loud sonic booms were heard and probably some fragments fell to the ground before the bolide returned to the space.

# Original source ("El Universal, Venezuela):

Recompensa por entregar meteorito

LOS ANGELES _ Cinco mil dólares de recompensa ha ofrecido la Universidad de California Los Angeles (UCLA) a quien entregue un fragmento del meteorito que atravesó la atmósfera terrestre y volvió al espacio a principios de este mes. Explica la agencia Efe que el fragmento deberá tener un mínimo de cien gramos de peso, y restos menores recibirán recompensas inferiores. Los científicos no han podido examinar nunca un meteorito que haya entrado en la atmósfera, permanecido un tiempo en la órbita terrestre y luego salido al espacio exterior, por lo que están muy interesados en investigar todo lo posible sobre uno de ellos. El meteorito en cuestión entró en la atmósfera el pasado día 3 sobre el cielo del estado de Nuevo México, donde creó una estrella brillante que siguió su camino hacia Texas, y allí quedó bajo la influencia de la órbita terrestre. El fragmento mayor del objeto celeste salió de la influencia de la órbita de la Tierra a la altura de California y dejó de brillar sobre la zona de Sierra Nevada, donde se oyeron estampidos por la ruptura de la barrera del sonido. En todo ese camino el meteorito debió dejar multitud de pequeños fragmentos que cayeron a la tierra, aunque serán difíciles de encontrar porque el suroeste de EE UU, es una región mayoritariamente desértica y poco poblada.

* A remark to this article, from the Cosmos mail list:

From: klopes
To: cosmos@rcp.net.pe
Date: Thu, 17 Oct 96 20:00:44 +0100

I disagree with this statement. When that flying saucer fell (or was a balloon, indeed...?) in Roswell, there were about 300 witnesses. This must be a specially crowded desert.

Part 4: On the right track

961101047 Caltech Seismology Lab Helps Pinpoint Location of Meteorite Fall
From: Ron Baalke
Date: Fri, 25 Oct 1996 23:05:38 GMT

PASADENA- Should anyone be inclined to do a bit of meteorite hunting this weekend for a $5,000 reward, Caltech seismologist Kate Hutton thinks she can provide some help.

According to Hutton, any larger chunks from the meteor that lit up the Western skies on the night of Oct. 3 may have landed in the Rose Valley area near Little Lake. Hutton figured this out by analyzing data from 31 of the seismic stations belonging to the Southern California Seismographic Network (operated by Caltech and the U.S. Geological Survey). "As it fell, the atmospheric drag caused the meteroid to explode in mid-air at least twice," Hutton says. "The explosions generated sound waves in the air similar to a sonic boom, which were detected by the seismographs. Using a procedure that is very similar to the one used to locate earthquakes underground, I used the arrival times of the sound waves at the various seismic stations to estimate where the explosions occurred." Two of the explosions were well located, Hutton adds. Both were 20 to 30 miles above the Fivemile Canyon area in the eastern Sierra foothills. The explosions were separated by about 25 seconds, and the second was about five miles lower than the first and about a mile further eastward. Based on this data and on eyewitness accounts provided by John Wasson of UCLA and Mark Boslough (Ph. D. from Caltech, 1984) of Sandia National Laboratory in New Mexico, Hutton thinks that any larger fragments that survived the firey entry into Earth's atmosphere would have landed to the east-northeast of the explosions, perhaps in the Rose Valley area near Little Lake. Smaller fragments may have fallen more or less straight down from where the explosions occurred.

The Little Lake area would probably be the more seductive area to search, and for a very good reason. UCLA has offered a $5,000 reward for the first fragment that weighs at least four ounces.

Hutton says the seismographic instruments didn't pick up a meteorite impact on Earth, but this is not surprising, since a single fragment would probably have to weigh several tons in order for its impact to be detected. The term "meteorite," by the way, refers to chunks of extraterrestrial debris that survive the entry into the atmosphere and end up on the ground. "Meteoroids" are chunks that travel through space, while "meteor" is the proper designation for the light show produced by a rock from outer space slowing down in the Earth's atmosphere.

Any surviving meteorite fragments would probably have a fresh black matte crust. If the meteorite struck something on the ground, part of the crust might have chipped off to reveal a lighter interior. If anyone finds a meteorite fragment weighing at least four ounces, he or she should get in touch with Dr. John Wasson at UCLA. Wasson's e-mail address is wasson@igpp.ucla.edu.

Contact: Robert Tindol (818) 395-3631 tindol@caltech.edu

Part 5: A year later

Meteorite Falls From Oct 1996
From: Ron Baalke
Date: Wed, 8 Oct 1997 14:14:51 GMT

NEWS RELEASE OCT. 1, 1997

Albuquerque, N.M. After a year of detective work involving scores of eyewitness reports from across New Mexico and Texas, a group of scientists has concluded that the Earth collided with a swarm of cosmic debris on the night of Oct. 3-4, 1996.

The most widely-reported fireballs were ones over eastern New Mexico and the Texas panhandle, and another near Bakersfield, California, exactly 104 minutes later. The relationship among the times, locations, and trajectories of the meteors seemed too unlikely to be mere coincidence, and had initially led some scientists to believe that a single object skimmed through the atmosphere and re-entered after a single orbit.

After careful analysis of a videotape taken from El Paso, Texas, together with eyewitness reports, Mark Boslough of Sandia National Laboratories and Peter Brown of the University of Western Ontario found that the first meteor entered at too steep of an angle to skip off the atmosphere. They are now convinced that the two fireballs observed over New Mexico/Texas and over California were two different objects.

They also determined the most likely location in the Texas panhandle where meteorites might have fallen, and John Wasson (UCLA) has re-issued a reward for a sample. Brown and Boslough believe that any meteorites reaching the ground in the Southwest would most likely be found south of Amarillo, near the towns of Hereford and Canyon, where they were carried by winds to the east of the visible trajectory. The most likely place for small meteorites to have landed would be in an oblong area about 10 miles ESE if Hereford, but any larger meteorites would be in a strip that stretches as far as 10 miles east of Canyon.

This part of the Texas Panhandle is well-known for its abundance of meteorite finds because it is flat, with little vegetation and few natural rocks on the surface. The most famous area is southwest of Plainview, where over 900 meteorites were recovered after they fell in 1903, and were still being found as late as 1949.

Over the past year, two groups of scientists from Los Alamos National Laboratory and the National Oceanic and Atmospheric Administration have also reported low-frequency sound data showing that the Earth's atmosphere was hit by at least 60 objects within several hours of the two that were originally reported, two of which were also observed by Defense Department satellites.

Most of the infrasound-producing meteors occurred during daylight hours and were not seen by witnesses, but the large number of collisions taking place that night helps explain why two bright ones with such similar trajectories would be seen so closely spaced in time. Although the scientists eliminated their hypothesis of a single object bouncing off the atmosphere and re-entering it later, they are still very interested in the events of one year ago because it means the Earth collided with a cluster of objects, perhaps pieces of a broken asteroid. A sample of one of these meteorites would help scientists determine what kind of asteroid spawned the fragments and better understand how they break apart and explode in the atmosphere, says Sandia's Mark Boslough.

Prof. John Wasson is seeking such samples and is offering a reward of $2,000 for the first confirmed sample as large as 4 ounces, and he urges persons living within the calculated fall area to look in their fields, on the roofs of buildings, in stock tanks and other locations where stones would not be expected. Meteorite hunters are reminded to get permission of land owners, and that any stones automatically belong to the owner of the property on which it is found. The stones are most likely to be black with a fresh matte texture. Samples should be sent to Prof. Wasson at the Institute of Geophysics, UCLA, Los Angeles, CA 90095, or to Dr. Adrian Brearley, Institute of Meteoritics, University of New Mexico, Albuquerque, NM 87131. Each sample will be acknowledged, but those that are not meteorites will not be returned unless a return self-addressed envelope is provided.

Part 6: Coincidence?

* October 3, 1815:

o In 1815, a meteorite was observed to fall from the sky in Chassigny, France, after loud sonic booms were heard. The Chassigny meteorite was later identified as a Mars meteorite and was the first Mars meteorite ever found. Although it was estimated that the meteorite originally weighed about 4,000 grams (~9 pounds), and there is only about 570 grams preserved of the meteorite today. Chassigny is distinctly different from the other Mars meteorite, so it has been assigned its own signature subgroup, chassignite. Since so little of Chassingy was preserved, and it is the only meteorite in its subgroup, the Chassigny meteorite is the rarest of the Mars meteorites.

* October 3, 1962:

o A meteorite landed near Zagami, Nigeria about 10 feet away from a farmer who was trying to chase crows from his corn field. The farmer heard a tremendous explosion and was buffeted by a pressure wave. After a puff of smoke and a thud, the meteorite buried itself in a hole about 2 feet deep. The Zagami meteorite was later identified as a Mars meteorite. Weighing at about 18,000 grams (40 pounds), the Zagami meteorite is the largest single individual Mars meteorite ever found.

(from AstroNet)

New Photos of Mars Meteorites

The new photos include Zagami, Chassigny, Nakhla, Lafayette, ALH 84001, ALHA 77005 and QUE 94201.

I have photos of 11 of the 12 known Mars meteorites, and the one I'm missing is Yamato 793605. If anyone has a photo of this meteorite, I'd appreciate it if you contact me.

Ron Baalke baalke@kelvin.jpl.nasa.gov

Could anybody find a piece of the October 3 bolide and win the 5000$ reward?...

Or it disintegrated in a show of gold?

Two "Tunguskas" in South America in the 1930's? The Rio Curaca event

Duncan Steel
WGN Journal
Fri, 01 Dec 1995 15:31 EST

There is evidence that there were two massive bolide explosions which occurred over South America in the 1930's. One seems to have occurred over Amazonia, near the Brazil-Peru border, on August 13, 1930, whilst the other was over British Guyana on December 11, 1935. It is noted that these dates coincide with the peaks of the Perseids and the Geminids, although any association with those meteor showers is very tentative. The identification of such events is significant in particular in that they point to the need for re-assessment of the frequency of tunguska-type atmospheric detonations.

In 1989 an article by N.Vasilyev and G.V. Andreev in the IMO Journal (1) drew attention to a discussion, published in 1931 by L.A. Kulik (2), of a possible Brazilian counterpart to the Tunguska bolide explosion of 1908. The Brazilian event, which occurred on August 13, 1930, was described in the papal newspaper L'Osservatore Romano, the report being derived from Catholic missionaries working in Amazonia. That report, in Italian, was used as the basis of a front-page story in the London newspaper The Daily Herald (since closed down), which was published on March 6, 1931, and then seen by Kulik. (For the interested reader, a copy of the story is reprinted in the December 1995 Journal).

The locality of the explosion gives it it's name: The Rio Curaca event. This is close to the border between Brazil and Peru, at Latitude: 5 degrees South, Longitude: 71.5 degrees West.

Both of these newspaper stories were discussed in a recent paper by Bailey and co-workers (4), who provide an English translation of the story which appeared in L'Osservatore Romano. Since that paper should be accessible to many readers of WGN, I will not give an extensive account of it here. I will, however, just mention that although the eye-witness accounts give do cover the phenomena which one might expect to be produced by a massive bolide, there are some other interesting reported observation which would require some explanation. These include the following:

* An ear-piercing "whistling" sound, which might be understood as being a manifestation of the electrophonic phenomena which have been discussed in WGN over the past few years.
* The sun appearing to be "blood-red" before the explosion. I note that the event occurred at about 8h local time, so that the bolide probably came from the sunward side of the earth. If the object were spawning dust and meteoroids-- that is, it was cometary in nature--then, since low-inclination, eccentric orbits produce radiants close to the sun, it might be that the solar coloration (which, in this explanation, would have been witnessed elsewhere) was due to such dust in the line of sight to the sun. In short, the earth was within the tail of the small comet, if this explanation is correct.
* There was a fall of fine ash prior to the explosion, which covered the surrounding vegetation with a blanket of white: I am at a loss with regard to this, if the observation is correct (and not mis-remembered as being prior-, rather than post-impact).

Bailey et al. also discuss the fact that the Rio Curaca event occurred on the day of the peak of the annual Perseid meteor shower, but conclude that this is likely to be purely a coincidence. The date is also close to august 10, on which day in 1972 a large bolide was filmed skipping through the upper atmosphere above western Wyoming and Montana, departing from the earth above Canada (4). Again, this may be merely a coincidence.

A brief discussion of the event is also given by R. Gorelli in august 1995 issue of Meteorite! magazine.

Two "Tunguskas" in South America in the 1930's? The Rupununi event

Duncan Steel
WGN Journal
Fri, 01 Dec 1995 16:00 EST

I now move on to the suspected explosion over British Guyana in 1935. The main source for information on this event is a story entitled Tornado or Meteor Crash? in the magazine The Sky (the forerunner of Sky and Telescope) of September 1939(5). A report from Serge A. Korff of the Bartol Research Foundation, Franklin Institute (Delaware, USA) was printed, he having been in the area--the Rupununi region of British Guyana--a couple of months later. The date of the explosion appears to have been December 11, 1935, at about 21h local time. I might note that this is near the date of the peak of the Geminid meteor shower, but yet again this may be merely a coincidence. The location is given as being near Lat: 2 deg 10min North, Long: 59 deg 10 min West, close to Marudi Mountain.

Korff's description suggested that the region of devastation might be greater than that involved in the Tunguska event itself. On his suggestion, a message was sent to William H. Holden, who in 1937 was in the general region with the Terry-Holden expedition of the American Museum of Natural History. That group hiked to the top of Marudi Mountain in 1937 November and reported seeing an area some miles across where the trees had been broken off about 25 feet above their bases, although regrowth over two years in this tropical jungle had made it difficult to define the area affected. Holden confirmed, on returning to New York, that he believed the devastation was due to an atmospheric explosion of cosmic origin. An explorer and author, Desmond Holdridge, also visited the region in the late 1930's and confirmed the suspicion that a comet or asteroid detonation was responsible.

Korff obtained several local reports, the best being from a Scottish gold miner, Godfrey Davidson, who reported having been woken by the explosion, with pots and pans being dislodged in his kitchen, and seeing a luminous residual trail in the sky. A short while later, whilst prospecting, he cam across a devastated region of the jungle he estimated to be about five by ten miles (8 by 16 kilometers), with the trees all seeming to have been pushed over.

Holden was unsure of the origin of the flattening of the forest, and pointed out that similar destruction can result from tornados. Holdridge, however, reported eye-witness accounts in accord with a large meteoroid/small asteroid entry, with a body passing overhead accompanied by a terrific roar (presumably electrophonic effects), later concussions, and the sky being lit up like daylight. A local aircraft operator, Art Williams, reported seeing an area of forest more than twnety miles (32 kilometers) in extent which had been destroyed, and he later stated that the shattered jungle was elongated rather than circular, as occurred at Tunguska and would be expected from the air blast caused by an object entering away from the vertical (the most likely entry angle for all cosmic projectiles is 45 degrees).

There is a report of the Guyanan event, largely derived from the account in The Sky, in the newsletter Meteor News for March 1974. Apparently as a result of that, the publishers (Karl and Wanda Simmons, of Callahan, Florida) had some correspondence with a Mr. F.A. Liems of Paramaribo, Surinam, concerning a possible crater/event at Wahyombo in that country; he gives the location as Lat: 5.25 deg North, Long: 56.05 deg West. The letters date from 1976; apparently Liems died in 1982. In 1990, as a result of Andreev's article in WGN about the Brazilian event, Wanda Simmons sent copies to him, and he kindly sent copies on to me. Various notes/maps/letters are included, but it is difficult to know what to make of them: my impression is that this concerns something that occurred some time ago, not in this century, and it's linkage with an incursion by an asteroid or comet is far from clear.

References:

1) N. Vasilyev, G. Andreev, WGN 17:6, 1989, pp. 247-248.
2) L.A. Kulik, Priroda i Ljudi 13-14, 1931, p.6
3) M.E. Bailey, D.J.Markham, S. Massai, J.E. Scriven, The Observatory 115, 1995, pp. 250-253.
4) Sky and Telescope 44, 1972, pp. 269-272.
5) The Sky, September 1939, pp. 8-10 and p.24.

Below is the wording of the Newspaper article printed in The Daily Herald on March 6, 1931.

+ MENACE OF METEORS LIKE HUGE BOMBS FROM SPACE
+ HURRICANE OF FLAME
+ BLAZING BOLTS FIRE FORESTS
+ MANKIND'S LUCK

Another colossal bombardment of the earth from outerspace has just been revealed.

Three great meteors, falling in Brazil, fired and depopulated hundreds of miles of jungle.

News of this catastrophe has only now reached civilization because the meteors fell in the remote S. American wilderness.

It was yet another lucky escape of mankind from an appalling and unrealized peril.

The last great meteor fell in Siberia in 1908. In a district so remote that only last year were details of it's destruction given to the world. Had either of these two meteor falls chanced to strike a city in a densely populated country, frightful loss of life and damage would have been cuased. "A Meteor", Mr. C.J.P. Cave an ex-president of the Royal meteorological Society stated recently "carries in front of it a mass of compressed and incandescent air.

When it strikes the earth, this air "splashes" in a hurricane of fire...The Brazilian meteors are reported (says the Central News) by Father Fidello of Aviano. writing from San Paulo de Alivencia in the state of Amazonas, to the papal newspaper, "Osservatore Romano".

BLAZING FOREST The meteors fell almost simultaneously during an amazing storm. Terrific heat was engendered. Immediately they struck the ground the whole forest was ablaze.

The fire continued uninterrupted for some months, depopulating a large area. The fall of the meteor was preceded by remarkable atmospheric disturbances. At 8 o'clock in the morning the sun became blood-red and a penumbra spread all over the sky, producing the effect of a solar eclipse. Then an immense cloud of reddish powder filled the air and it looked as if the whole world was going to blaze up.

WHISTLING SOUND The powder was succeeded by fine cinders which covered trees and vegetation with a blanket of white. There followed a whistling sound that pierced the air with car-breaking intensity, then another and another.

Three great explosions were heard and the earth trembled. The Siberian meteor of 1908 completely destroyed the forest over an area of 70 miles in diameter. It's roar was heard 600 miles away and it's glare maintained twilight all night even in England.

The sky is falling! Witnesses often reluctant to report Canada's many meteorite strikes 

Daniel Macisaac
Edmonton Sun
Mon, 04 Feb 2008 10:48 EST

Who you gonna call?

No, not when you see a ghost - but when you spot a meteorite falling from the sky.

It happens more often than you would think.

When a suspected meteorite landed on a Spruce Grove golf course recently, a number of residents continued to come forward with their own stories.

LOUD

"We both heard a very loud sound," Jocelyn and Michael Pederson wrote in an e-mail, describing the incident. "It was like a plane descending, and we thought a plane may have crashed.

"It was very close."

Mike Elliott, 49, his wife and a friend were headed south toward Spruce Grove around that time when, "all three of us saw the same thing."

"Its trajectory was straight down, and it was greenish in colour with a white spot, leaving somewhat of a tail behind it," Elliott said. "It surprised all of us, and we all thought it had to be a meteorite."

Elliott said it was the third meteorite he's spotted in his life - while veteran stargazer Evelyn Jones claims two.

Jones, who lives outside Breton, described driving home recently and also suddenly "looking up at the sky and seeing this thing with a big tail coming from behind a row of 60-foot spruce trees," - describing a glowing object resembling a honeydew melon.

"I'm 64," she said when asked her age, adding, "and I'm of sound mind."

Alan Hildebrand, a professor at the University of Calgary, tracks meteorites, or "fireballs," for the Canadian Space Agency as part of his study of asteroids and comets. And he concedes there can be a reluctance to report them.

"People do often tell me things like, 'I went into work and told them what I saw, and they told me I was crazy,' " he said. "So, I suppose they do have cause for fear.

"But that is another reason to report sightings because then other people might come forward, too."

But Hildebrand says that some 70 meteorites do indeed fall on Canadian soil or water every year. And he adds that's where organizations like the Meteorite and Impacts Advisory Committee come in. The committee maintains a website [HERE], which includes online reporting forms.

FIREBALLS

Barring that, Hildebrand said people spotting fireballs may also simply tell staff at institutions like the Telus World of Science, who can pass on details to him.

The geology professor says besides assisting researchers understand how the solar system works, reporting meteorites can help rule out catastrophes like plane crashes.

Hildebrand recommends would-be reporters take notes on aspects like height, distance and direction - and not rely on memory alone.

"Tracking down a meteorite is like the police trying to solve a crime," he said. "It's good to have multiple witnesses."

The Comet and the Chicago Fire 

Anonymous
thunderbolts.info
Mon, 06 Feb 2006 16:10 EST

For nearly one and a half centuries, the cause of the most notorious fire in U.S. history has been a source of "heated" controversy. Some researchers suggest that a disintegrating comet ignited the blaze. But the electrical theorists say that evidence most often ignored offers the best clues.

"With the heat increased the wind, which came howling across the prairie, until at last there arose a perfect hurricane. Mighty flakes of fire, hot cinders, black, stifling smoke, were driven fiercely at the people, and amid the terrible excitement hundreds of them had their very clothes burned off their backs, as they stood there watching with tearful eyes the going down of so many houses". -- James Goodsell's History of the Great Chicago Fire, October 8, 9, and 10, Published 1871 by J.H. and C.M. Goodsell.

Sunday evening, October 8, 1871 marked the beginning of one of the most devastating fires in U.S. history. Legend has it that "The Great Chicago Fire" resulted from an agitated cow kicking over a lantern in "Mrs O'Leary's barn". The dry leaves and parched wood of Illinois in early autumn were the perfect kindling for a wildfire, and the fire spread with extraordinary rapidity, consuming homes and buildings, leaping from rooftop to rooftop with the speed of a locomotive. Between October 8 and 10, an estimated 350 people perished. The fire destroyed the homes of up to one-third of the city's population, about 1,600 stores, 60 factories, and 28 public buildings. Four square miles of the city burned to the ground.

Contrary to popular folklore, the Chicago fire is not the worst in U.S. history. It was not even the worst to occur on October 8 that year. The same evening - in fact, at the same time, about 9:30 - a fierce wildfire struck in Peshtigo, Wisconsin, over 200 miles to the north of Chicago, destroying the town and a dozen other villages. Estimates of those killed range upward from 1200 to 2500 in a single night. It was not the Chicago fire but the simultaneous "Peshtigo Fire" that was the deadliest in U.S. history.

And there is more. On the same evening, across Lake Michigan, another fire also wreaked havoc. Though smaller fires had been burning for some time - not unusual under the reported conditions - the most intense outburst appears to have erupted simultaneously with the Chicago and Peshtigo fires. The blaze is said to have then burned for over a month, consuming over 2,000,000 acres and killing at least 200.

Concerning the Michigan outburst, it is reported that numerous fires endangered towns across the state. The city of Holland was destroyed by fire and in Lansing flames threatened the agricultural college. In Thumb, farmers fled an inferno that some newspapers dubbed, "The Fiery Fiend." Reports say that fires threatened Muskegon, South Haven, Grand Rapids, Wayland, reaching the outskirts of Big Rapids. A steamship passing the Manitou Islands reported they were on fire.

There can be no doubt that weather conditions at the time favored wildfires. But never before, and never since, has the U.S. seen such wildly destructive simultaneous conflagrations. This "coincidence", combined with many unusual phenomena reported by eyewitnesses, has led some to conclude that an extraordinary force, one not of the earth, was a more likely "arson" than either a misbehaving cow or a regional drought.

In 1883, Ignatius Donnelly, author of Ragnarok: the Rain of Fire and Gravel, suggested that in early historic times our Earth suffered great catastrophes from cometary intruders. To this claim he added: "There is reason to believe that the present generation has passed through the gaseous prolongation of a comet's tail, and that hundreds of human beings lost their lives". He was referring to the conflagration of 1871.

Is there plausible evidence that a comet may have caused the Chicago fire and its regional counterparts? In 1985, Mel Waskin, who had earlier discovered Donnelly's work, published a book, Mrs. O'Leary's Comet, suggesting that a comet did indeed spark the October 8th fires. More recently, Robert Wood, a physicist and aeronautical engineer formerly with Douglas Aircraft and McDonnell Douglas, gained attention from the Discovery Channel and other media for proposing the same idea.

The proponents of the cometary explanation cite many fascinating details confirmed by eye witness reports: the descent of fire from the heavens, a great "tornado" of fire rushing across the landscape and tearing buildings from their foundations, descending balls of fire, a rain of red dust, great explosions of wind accompanied by blasts of thunder, buildings exploding into flame where no fire was burning, and a good deal more. Some of the parallels with the later Tunguska event are impossible to miss.

It seems that the records of the conflagration hold many clues that are almost never mentioned in scientific discussion of the Chicago fire. Over time the clues have virtually disappeared. They have disappeared because they are not meaningful to minds conditioned by popular ideas about how the "Chicago fire" started and what is "scientifically" possible. Within these habits of perception, the most important evidence will often go unnoticed or unremembered.

Where was Comet Biela?

A strange thing happened to comet Biela in 1845. The nucleus of the comet split into two partners. The "smaller" comet (lower left in the picture above), subsequently became more active and brighter than the larger. And that was only the beginning.

In 1883, twelve years after the Chicago fire, Ignatius Donnelly published a widely read book, Ragnarok: the Rain of Fire and Gravel. Though the book dealt primarily with the evidence for cometary disasters in ancient times, Donnelly suggested that the Chicago fire provided a small glimpse of the terror experienced by our earlier ancestors. "There is reason to believe that the present generation has passed through the gaseous prolongation of a comet's tail, and that hundreds of human beings lost their lives".

Reflecting on the simultaneous events around Lake Michigan on the evening of October 8, 1871, Donnelly posed the underlying mystery: "At that hour, half past nine o'clock in the evening, at apparently the same moment, at points hundreds of kilometers apart, in three different states, Wisconsin, Michigan, and Illinois, fires of the most peculiar and devastating kind broke out, so far as we know, by spontaneous combustion". (We take up the historic testimony cited by Donnelly and others in tomorrow's "Picture of the Day").

Donnelly believed he could identify the cause of the devastation. He said it was Comet Biela, a comet that captured attention from astronomers in 1826, returned for a few predictable visits, broke into two nuclei, and then disappeared.

The comet was named after Austrian officer W. von Biela, who observed the body in February 1826. By following the path of Biela, the French astronomer Marie-Charles-Théodore de Damoiseau estimated the time of its return. He said the comet would cross the orbit of the Earth about one month ahead of our planet's arrival at the same spot.

Donnelly does not mention that ten days after Biela's announcement, a French astronomer John Felix Adolphe Gambart also sighted the comet. Both Biela and Gambert calculated the orbit, recognizing that earlier comet apparitions in 1772 and 1805 were the same object that appeared in 1826. And Gambert, along with other astronomers, predicted that the comet would strike the earth on its return, which he projected for October 29, 1832.

Damoiseau's prediction was correct. Earth missed the comet by about a month.

On its anticipated 1846 return, Biela was first sighted in late 1845 as it moved toward perihelion (its closest approach to the Sun), astronomers were surprised to see that the head of the comet had acquired a faint satellite. It had split in two (picture above), something we now know to be fairly common for comets, but still mysterious to cometologists. In 1845, the event seemed unprecedented. As noted by Carl Sagan and Nancy Druyan in their book Comet, "the finding was so bizarre that the first astronomer to note this twinning dismissed it as some internal reflection in his telescope".

In Robert Chapman's and John Brandt's The Comet Book certain details of Biela's return are fascinating. The discovery of a partner occurred on January 13, 1846, when "a faint satellite comet was observed a small distance from the main comet". Two tails were seen parallel to each other. "Over the next month the fainter of the two comets increased in brightness and finally became brighter than the 'main' comet. The situation then reversed and the main comet became the brighter one again. In addition, the main comet grew a second tail and a luminous bridge of material joined the two comets" [emphasis ours]. At this time the two nuclei were apart an estimated 250,000 kilometers, about two thirds of the distance separating Earth and the Moon.

Donnelly's account at this point diverges from the history told by Chapman and Brandt. As Donnelly tells it, "In 1852, 1859, and 1866, the comet should have returned, but it did not". But Chapman and Brandt - prominent figures at NASA's Goddard Space Flight Center at the time of their book's publication - say that the twin comet-heads did indeed appear at the appointed time in 1852. This reappearance is, in fact, well documented. And one detail in Chapman's and Brandt's account rarely shows up in standard discussions of cometology:

"...Both comets returned at the predicted time, though they were over 2 million kilometers apart [emphasis ours]. Once again the two comets took turns as the brighter of the pair. On at least one occasion a bright jet was seen between the two heads" [emphasis ours].

Though Sagan and Druyan report the splitting of Biela, they do not mention the jet, an event for which the standard view of comets has no theoretical reference.

The rest of Donnelly's discussion of Biela is in general agreement with the summary by Chapman and Brandt. Amazingly, and with the aid of a startling and unpredicted meteor shower on November 27, 1872, Professor W. Klinkerfues of Berlin, calculated the trajectories of the meteoric falls, concluding that they were the remains of the comet. This, in turn led him to send instructions to Norman Pogson, Government Astronomer at the Madras Observatory in India (far enough south to allow a good view). Pogson's answer to Klinkerfues, dated December 6, said he "found Biela immediately" on the first clearing of the sky, and on the second day he saw it again. It showed no tail, he said.

As Chapman and Brandt put it, this was either an "incredible coincidence", or it was the actual last view of the comet.

The spectacular meteor shower that inspired Klinkerfues to identify it with Biela has long since become an annual event - sort of - called the Andromedids. And astronomers do not hesitate to connect the shower to Biela. Each year the Earth passes through the remains of the comet, but with widely varying consequences. And the effect today is trivial by comparison with the November 1872 occurrence. Today the shower peaks around mid-November, averaging less than three meteors per hour - hardly deserving the title "shower". On the night of November 27, 1872, however, records show several thousand meteors per hour - a direct and obvious link to the disintegration of the comet.

It remains to be asked, then, whether the fragmentation of Biela, a comet on a path intersecting the orbit of the Earth, and predicted by some astronomers to collide with the Earth in 1832, might have been the source of the "great conflagration" in 1871. The comet had split at least 25 years earlier (the 1846 appearance), and the two partners had separated by more than 2 million kilometers by 1852. So whether or not Klinkerfues observed Biela after the spectacular shower of November 1872, we know he did not report seeing two bodies. Hence, at least one of the partners intersecting Earth's path had presumably already disintegrated entirely, leaving the possibility that on a subsequent orbit the Earth moved into debris left by the body.

The facts on the Andromedids, including their erratic occurrence over the years and the obvious dispersal and depletion of the cometary debris over a century and a half, cannot give us a definitive answer to Donnelly's views on Biela. But as for plausibility, the answer is definitive. Many facts are consistent with the interpretation, and there are no facts that exclude the interpretation.

Of course, it is not necessary to identify an intruder, in order to see the evidence of an intrusion. No one questions the exploding Tunguska comet, asteroid or meteor on the basis that astronomers cannot identify the incoming object.

But of all the scientific details about comet Biela, perhaps none stands out more dramatically than the fact almost never mentioned - a jet forming between the two nuclear fragments when they were 2 million kilometers apart. In the purely gravitational and mechanical terms that astronomers have sought to apply to comets, this jet is inconceivable. But when we remember how inconsequential is gravity in the presence of the electric force, the improbability disappears.

In fact, the jet is a clue more vital by far than the popular "scientific" commentary on Donnelly's hypothesis. By directing our attention to the electrical nature of comets, it also invites us to look again at the historic testimony, with an eye to details long unnoticed or forgotten.

Human Testimony Reconsidered

All investigators of the Chicago fire and its devastating regional counterparts rely on human testimony. But how should we view such testimony when it suggests things that are not currently believed? Good science will not ignore witnesses when, in unison, they suggest new lines of investigation.

On the evening of October 8, 1871 devastating fires erupted at virtually the same moment in three different states in the region of the Great Lakes - Wisconsin, Illinois, and Michigan. The outbursts included the notorious "Chicago fire", but also an even more devastating fire in Wisconsin, the worst in U.S. history, covering some 400 square miles. At the same time, wildfires also erupted across much of Michigan. In his book Ragnarok: The Age of Fire and Gravel, published in 1883, Ignatius Donnelly proposed that the simultaneous outbursts were no coincidence; they were the effect of our Earth meeting up with a fragment, or fragments, of comet Biela, a body that had disintegrated a few years earlier while on an Earth-threatening path.

As Donnelly reports it, in the Wisconsin fire near Lake Michigan, a large area including the town of Peshtigo and several neighboring cities was "swept bare by an absolute whirlwind of flame". His review of the event, based on eyewitness accounts, was taken primarily from the book "History of the Great Conflagration", by James W. Sheahan and George P. Upton (1871). It includes the following report:

"At sundown there was a lull in the wind and comparative stillness. For two hours there were no signs of danger; but at a few minutes after nine o'clock, and by a singular coincidence, precisely the time at which the Chicago fire commenced, the people of the village heard a terrible roar. It was that of a tornado, crushing through the forests. Instantly the heavens were illuminated with a terrible glare. The sky, which had been so dark a moment before, burst into clouds of flame. A spectator of the terrible scene says the fire did not come upon them gradually from burning trees and other objects to the windward, but the first notice they had of it was a whirlwind of flame in great clouds from above the tops of the trees, which fell upon and entirely enveloped everything". [Emphasis ours]

For many of the witnesses it seemed as if the biblical "last days" had come. Though well accustomed to wildfires, they had seen nothing like this before. "They could give no other interpretation to this ominous roar, this bursting of the sky with flame, and this dropping down of fire out of the very heavens, consuming instantly everything it touched".

Donnelly continues quoting from Sheahan and Upton: "No two give a like description of the great tornado as it smote and devoured the village. It seemed as if 'the fiery fiends of hell had been loosened', says one. 'It came in great sheeted flames from heaven', says another. 'There was a pitiless rain of fire and SAND. The atmosphere was all afire'. Some speak of 'great balls of fire unrolling and shooting forth, in streams'. The fire leaped over roofs and trees, and ignited whole streets at once". [Emphasis ours]

Donnelly notes that many of the victims were found in open spaces with "no visible marks of fire nearby" and "not a trace of burning upon their bodies or clothing". Many were found huddled together "in what were evidently regarded at the moment as the safest places, far away from buildings, trees, or other inflammable material, and there to have died together".

One clue, perhaps, is the mention of electrical phenomena:

"Much has been said of the intense heat of the fires which destroyed Peshtigo, Menekaune, Williamsonville, etc., but all that has been said can give the stranger but a faint conception of the reality. The heat has been compared to that engendered by a flame concentrated on an object by a blow-pipe; but even that would not account for some of the phenomena. For instance, we have in our possession a copper cent taken from the pocket of a dead man in the Peshtigo Sugar Bush, which will illustrate our point. This cent has been partially fused, but still retains its round form, and the inscription upon it is legible. Others, in the same pocket, were partially melted, and yet the clothing and the body of the man were not even singed. We do not know in what way to account for this, unless, as is asserted by some, the tornado and fire were accompanied by electrical phenomena".

It seems the idea that Mrs. O'Leary's cow triggered the conflagration in Chicago did not withstand investigation. Speaking of O'Leary's barn, the fire marshal testified: "We got the fire under control, and it would not have gone a foot farther; but the next thing I knew they came and told me that St. Paul's church, about two squares north, was on fire". They then checked the church-fire, but--"The next thing I knew the fire was in Bateham's planing-mill".

A writer in the New York "Evening Post" says he saw "buildings far beyond the line of fire, and in no contact with it, burst into flames from the interior".

To these references, Donnelly adds a quote from The Annual Record of Science and Industry" for 1876, page 84:

"The flames that consumed a great part of Chicago were of an unusual character and produced extraordinary effects. They absolutely melted the hardest building-stone, which had previously been considered fire-proof. Iron, glass, granite, were fused and run together into grotesque conglomerates, as if they had been put through a blast-furnace. No kind of material could stand its breath for a moment."

Another quote from Sheahan & Upton's Work:

"The huge stone and brick structures melted before the fierceness of the flames as a snow-flake melts and disappears in water, and almost as quickly. Six-story buildings would take fire and disappear for ever from sight in five minutes by the watch. . . . The fire also doubled on its track at the great Union Depot and burned half a mile southward in the very teeth of the gale--a gale which blew a perfect tornado, and in which no vessel could have lived on the lake. . . . Strange, fantastic fires of blue, red, and green played along the cornices of buildings".

Some additional detail and comments of interest appear in Mel Waskin's more recent book, Mrs. O'Leary's Comet (1985). Speaking of the Peshtigo outburst, he writes -

"Accompanying the firestorm and the wind was a rain of red hot sand. It was not clear to those eyewitnesses who survived their ordeal where this sand came from. It must have been raised from the earth by the incredible winds, but from where? There was sand on the beaches, but the beaches lay to the east, and the wind was blowing from the west and the south. There was no sand on the floor of the forest nor on the farmlands of Wisconsin".

Waskin also mentions incredible "balloons of fire" reported by many people, including one family that lived between Peshtigo and Green Bay. "The onslaught was so sudden that the family could only run to the center of an immense clearing on their farm where nothing combustible stood. They hoped to be safe, several hundreds yards from structures or trees.

"When the fire came, rushing on all sides of them, it did not in fact touch them. But eyewitnesses saw them die. A great balloon of fire dropped on them - father, mother, and four children. They were incinerated in an instant. Almost nothing was left of them".

"Many survivors described these great balls of fire falling from the sky. The whole sky was filled with them; round smoky masses about the size of a large balloon, traveling at unbelievable speed. They fell to the ground and burst". Waskin says that a brilliant blaze of fire erupted from the balloons as they landed, instantly consuming everything they touched.

Also noteworthy were the reports that the flames erupted from the basements of the stores when there was "no sign of fire in any other part of the building". And the basement fires burned with a strange light, "as if whisky or alcohol were burning".

As something of a footnote to this article, we note a contemporary report claiming that "The first (and most startling) piece of evidence is the recent discovery of a 26.5-kilogram carbonaceous chondrite meteorite on the shores of Lake Huron - 'ground zero' of the astral bombardment. This report, by Ken Riell, whose claims follow the work of Donnelly and Waskin, suggests the meteor is of the same composition as the incoming object in the Tunguska event in Siberia -- 1908.

Also of interest is a presentation on the Peshtigo fire by the Oconto County Web Project, which discusses the comet hypothesis as a "plausible" theory -

"Weather historians, using archives as a baseline, and adding information from recent decades, now offer a plausible theory. Meteor showers in Autumn are common in the upper great lakes. In recent years these showers have left burning chunks scattered over the entire region, some large enough to break through the roofs of homes and out buildings, starting fires in dry fields and wooded areas. With the tinder dry conditions present throughout the entire region on the night of October 8, 1871, such a meteor shower would easily have started what seemed like spontaneous fires in numerous places of Wisconsin, Michigan (upper and lower), and Illinois (the Great Chicago Fire). With the continuous thick smoke from smoldering smaller blazes already blanketing the land, and the unusually hot weather of that time making residents seek shelter inside their homes early in the evening, the meteors that entered the Earth's atmosphere could not easily be seen. This certainly would account for the sudden eruption of numerous blazes over the vast area at exactly the same time."

Nevertheless, it is hard to imagine the "cometary" explanation ever receiving the attention it deserves until those addressing the question familiarize themselves with the electric comet model. As we have already emphasized, without this deliberate reconsideration of the underlying question - what is a comet? - the investigator will either ignore or forget the most telling clues. In the above reports, for example, consider the following:

Whirlwind of flame or "perfect tornado"

Tornadoes are a slow electric discharge phenomenon. The ionized trails of cometary debris, descending through the ionosphere to the lower atmosphere, produces "lightning conductors" to allow various forms of "megalightning" to descend to the ground. One of the manifestations of a powerful direct discharge between the ionosphere and the Earth could well be a tornado, in which the usual swift lightning strike is replaced by a slower discharge. Powerful electromagnetic forces generate a devastating "charge sheath vortex" that slows the discharge while spreading the devastation on Earth.

Fire descending from the sky

As in the Tunguska event, the appearance of fireballs or electrically discharging debris, along with associated lightning manifestations from a clear sky, would be expected as an external body penetrated Earth's plasma sheath.

Rain of fire and sand

An electrically charged fragment of a comet nucleus will undergo explosive electrical fragmentation before reaching the Earth's atmosphere. The electrical model of comets envisions these bodies being formed by the same processes that created asteroids. Most, if not all, are as rocky as asteroids. The result of their fragmentation will be a meteoric shower of granulated silicates, or sand, mixed with flammable gases and electric discharge phenomena - a 'biblical' rain of fire and sand.

Descending "balloons" of fire

It is well established that comets discharge carbon compounds that would be flammable in the Earth's oxygen atmosphere. Gaseous balls of fire would combine with various weird manifestations of megalightning, reaching through the meteoric shower of dust to the ionosphere, almost 100 kilometres above the Earth. The spectacle would be beyond normal experience. In addition, near the Earth, ball lightning could be expected, given the extreme electrical conditions - and the presence of ball lightning is surely the plausible explanation for descending "balloons" with the power to incinerate objects they strike.

Buildings exploding with fire when no fire was yet present

Electrical discharges would take place between metal objects inside buildings, igniting any flammable materials. The same would hold true for the hapless man found with melted coins in his pocket but clothes intact and no other signs of burning. There is, in fact, no other natural explanation for this enigma.

Colorful flames running along cornices of buildings

This is the usual description of a glow discharge from sharp edges of rooftops, seen in the midst of powerful electrical storms. It is called "St. Elmo's fire". The different colors of the flames are due to the metallic ions sputtered from the surface material.

Fusing of fire-proof building material

Plasma discharges can be used to melt anything. Industrially, plasma torches are used to destroy the most refractory materials.

Basements exploding

"...the basement fires burned with a strange light, "as if whisky or alcohol were burning". Whisky or alcohol burns with a ghostly blue light. Similarly, electrical glow discharges from grounded metallic objects or electrical wiring in the basements of buildings would emit a flickering, eerie blue light. Any trapped flammable gases formed in the basements would be ignited by the discharge, resulting in explosions.

-------------------

Our purpose here is not to suggest a definitive answer to the "Great Conflagration". But the cost of ignoring evidence should be obvious. The moment one entertains the electrical vantage point, if only to compare the explanatory power of alternative views, the most incongruous elements of the story become predictable features. And who could deny that this ability to resolve paradoxes is the mark of a hypothesis that deserves consideration?

Comet Biela and Mrs. O'Leary's Cow 

Laura Knight-Jadczyk
sott.net
Sun, 03 Feb 2008 07:42 EST

©Unknown

Cometary fire ruins, as seen from the corner of Dearborn and Monroe Streets, Chicago, 1871.

Last night we watched Super Comet - After the Impact, a Discovery Channel special that basically takes the comet that wiped out the dinosaurs and put into modern times. They added some cheesy drama, following the struggles of several individuals or groups, before, during, and after the impact, to show how people would react to such a global cataclysm. They used the same type of cometary body assumed to have caused the extinction of the dinosaurs, the same size, same impact location, and utilized all the computer modeling they have done on this past event to try to show what might happen (and to show what they think happened then). Not terribly creative and suggests that they really don't know all the effects of such an impact and are just putting things together from what little they have been able to figure out about that one impact, some (or much) of which may be just speculation, though I'm sure that there is some good science going on there.

This show highlights what we have already noted in this series of articles: the difference between the American School of Asteroid impacts that happen only at millions of years intervals and the British School which posits that showers of much smaller objects occur with great frequency in between those millions of years events.

The cheesiest part of this "docu-drama" was, of course, the depicted foibles of the humans experiencing the event. But, in a way, even those depictions were useful. The one guy who simply couldn't grasp the nature of the event, kept traveling "home" (which happened to be the site of the impact) even when it was clear that there was no home left. His emotions basically drove him to his own death.

Other people continued to act as if the world was still the same place and suffered thereby, though they learned to cope. What was clearly evident was that it was lack of knowledge about such events that was the chief problem for all of them.

During the course of the show, one of the experts made the remark "WHEN it happens," as though he - and the rest of them - knew for a fact that this was on the agenda for our near future. The very fact that so many scientists are working on these problems, including a large number of them studying the possible human reactions and behaviors and how to deal with masses of people, should warn us that there IS something they aren't telling the masses in the headlines of our daily newspapers, though certainly they are "testing" public reactions with shows such as Super Comet - After the Impact.

On my desk, before me, I have a book out of the more than 30 volumes and scores of papers on the topic of comet and asteroid impacts that I have collected in the course of this study. The title of this book is Hazards due to Comets and Asteroids edited by Tom Gehrels, with 120 contributing authors, published by the University of Arizona Press in 1994.

There is something in this book that I want to bring to your attention before we get on to our main catastrophe of the day: Mrs. O'Leary's Cometary Cow.

The volume mentioned above, Hazards due to Comets and Asteroids, which we note was published in 1994, (in reaction to the impending Comet Shoemaker-Levy event vis a vis Jupiter), contains a paper beginning on page 1225, (yeah, it's a BIG book!), that is written by Robert L. Park of The American Physical Society, Lori B. Garver of the National Space Society and Terry Dawson, a staffer for the House Committee on Science, Technology, and Space working for the Committee's then Chairman, Rep. George Brown (See him listed HERE). The following is a condensation of the main points of this paper:

Our understanding of the history of Earth and its inhabitants is undergoing a radical change. The gradual processes of geologic change and evolution, it is now clear, are punctuated by natural catastrophes on a colossal scale - catastrophes resulting from collisions of large asteroids and comets with Earth. It is, to use the popular term, a "paradigm shift."

This "new catastrophism," is not unlike the revolutions brought about by the heliocentric solar system of Copernicus, or Darwinian evolution, or the big bang. In retrospect, such revolutionary ideas always seem obvious. On reading the Origin of Species, Thomas Huxley remarked simply: "Why didn't I think of that." Now, looking at the Moon, we find ourselves wondering why it took so long to ask whether the process that cratered its surface is still going on. [...]

The long time scale between major impacts has implications for public policy. Governments do not function on geologic time. On the North Dakota prairie near the town of Grand Forks, lie the abandoned ruins of America's ballistic missile defense system. ... Built in accordance with the ABM treaty, the Grand Forks facility was meant to defend our retaliatory capacity. It was declared operational in 1975 - and decommissioned the same year. National leaders had been persuaded by some scientists that the Grand Forks facility would meet the threat to our intercontinental ballistic missile fleet, even though other scientists warned that the system was dangerous and ineffective. It was closed because the money to operate it was needed for other projects that were deemed to be more urgent.

The lesson of Grand Forks is as old as human history: societies will not sustain indefinitely a defense against an infrequent and unpredictable threat. Governments often respond quickly to a crisis, but are less well suited to remaining prepared for extended periods. Even on the brief sacle of human lifetimes, resources are eventually diverted to more immediate problems, or defenses are allowed to decay into a state of unreadiness. According to news accounts, in the great flood of 1993, the U.S. Corp of Engineers prepared to close the massive iron gates in the vast complex of levees on the Mississippi and its tributaries only to discover that some of the gates had been removed and sold for scrap. Periodic inspections had been suspended to save money. Indeed, civilization will do well to survive long enough to be threatened by a major asteroid impact; our own destructive impulses of the unanticipated consequences of our technologies seem likely to do us in first. It is unrealistic to expect governments to sustain a commitment to protection against a rare occurrence when they are constantly under pressure to respond to some perceived immediate crisis.

Particularly now [1994], with nuclear weapons being dismantled by the major powers, any talk of a nuclear defense against such an unlikely hazard as cosmic collisions will be seen as an effort by the weapons community to sustain itself. The risk of diversion of any mitigation system to military uses must be regarded as a more immediate hazard. [...]

Given the frequency of past collisions, major impact is unlikely to occur in the next century. [...]

Discussion of mitigation may serve one public purpose. It is important that devastation not be accepted as inevitable, otherwise society might prefer not to know when it is coming. An asteroid interception workshop hosted by NASA in 1992 concluded that available technology can deal effectively with a threatening asteroid, given warning time on the order of several years. That conclusion validates the view that current efforts should concentrate on detection and orbit determination.

The challenge of science is to identify objects that threaten Earth and work out the timetables for their arrival. Here the challenge is straightforward and technical. [...]

The emphasis has properly been on impacts that would be expected to have global consequences. Even for objects too small to produce more than local effects, however, it has been pointed out that an impact might be misidentified as a nuclear explosion. Misidentification would be most likely among nations that have recently joined the ranks of "nuclear powers" and would therefore be expected to have less sophisticated means of verification.

It is more than a hypothetical concern. We recall that the 1978 South Indian Ocean anomaly, detected by a Vela satellite, was suspected at the time of being a South African-Israeli nuclear test. In spite of the failure to find any confirming evidence from intelligence sources or atmospheric monitoring, it created international tensions that lasted for years. At the time, there were suggestions that it might have been an artifact produced by micrometeorite impact on the Vela satellite itself, but little serious consideration seems to have been given to the idea that the satellite had observed the fireball from an asteroid impact in the atmosphere. A 1990 satellite observation of an apparent asteroid impact fireball over the Western Pacific has been described by Reynolds (1993). The danger of misidentification, which grows as weapons proliferate among less sophisticated nations, is meliorated in part by publicizing the possibility. The only sure means of avoiding an unfortunate response, however, would be for everyone to know the impact is coming. Which again places the emphasis on detection.

Efforts to persuade governments to invest significant resources in evaluation of the hazard of asteroid impacts must overcome what has been called the "giggle factor." Clearly, elected officials in Washington are not being inundated with mail from constituents complaining that a member of their family has just been killed or their property destroyed by a marauding asteroid. [...]

Congressional involvement has been confined to the Committee on Science, Space and Technology of the U.S. House of Representatives, whose current chair, George Brown of California, has maintained an interest in the asteroid issue for several years. The committee directed NASA to conduct two international workshops on the asteroid threat. [...]

In March of 1993, the Space Subcommittee held a formal hearing to examine the results of the two workshops. Some members remain skeptical that the threat is real. But even among those who recognize that it is only a question of when a major impact will occur, there was no sense of urgency. [...]

The frequency of impacts of objects of various sizes is known only to limited precisions. In particular, objects up to several meters in diameter explode in the atmosphere without reaching the surface. Although the energy released in these explosions may be many times greater than that released by the Hiroshima bomb, they most frequently occur over the ocean or sparsely inhabited regions of Earth and go unreported. [...]

Congress is unlikely to take any action in the absence of public pressure. Once the public understands that Earth and the life on it have been shaped by cosmic collisions (and the process is continuing), they will be more likely to support the science needed to evaluate the threat. The scientific community must, therefore, concentrate on public education. [...]

All of this creates a dilemma. While it is important to inform the public, it is dangerous to encourage fear mongering. ... Scientists would do well, for example, to avoid such terms as "near miss." The public understands "near-miss" as the draft of wind from a truck that passes as you step off the curb - not a truck that went by six hours earlier. [...]

Even in such staid newspapers as the New York Times and Washington Post, articles may include a well-reasoned discussion of relative risk, but the headline writers find "doomsday rock," "space bullets" and "killer comet" irresistible. These headlines exploit the excessive fear engendered by events people feel powerless to control. The image of an indifferent mountain of stone and metal guided by the immutable laws of physics toward an inevitable rendezvous with Earth, is the stuff of nightmares. Remarkably, however, Nature has apparently provided a non-threatening demonstration. The impact of comet Shoemaker-Levy 9 on the back side of Jupiter in July of 1994 provides an historic opportunity to educate the public without terrorizing anyone.

Shoemaker-Levy 9, in its last pass by Jupiter, broke into a string of 21 major pieces. The energy released by the impacts of the full string will be equivalent to about a billion megatons of TNT. Although the pieces will impact on the side of Jupiter away from Earth, millions of amateur astronomers will be watching to see the flashes reflected from Jupiter's moons. A few hours later, the rotation of Jupiter will bring the impact region into view. There is great disagreement about what will be seen, but no one suggests that it will not be spectacular.

The asteroid-comet community needs only to insure that everything is fully and accurately explained; the message will take care of itself: (1) the energy deposited by the cosmic impacts is enormous (2) this is a process that is still going on.

This guy had a lot of faith in human beings, didn't he? He thought that all scientists had to do was to tell the public the truth and they would get enough support to fund cataloging the dangerous asteroids in earth-crossing orbits. He also thought that this was the main problem: asteroids that could be seen and listed.

What seems obvious to me is that someone else took the "Lesson of the Grand Forks Facility" in an entirely different way. The question that comes to my mind is this: are the Elite Powers creating a War On Terror as an immediate and constant pressure on the public to get the needed support for the stockpiling of nuclear weapons so they will have them to use on asteroids? You know, kind of a benevolent lie with a million or so innocent Iraqis being sacrificed to sustain it. Kind of like the Madeleine Albright thing: In 1996 then-UN Ambassador Madeleine Albright was asked by 60 Minutes correspondent Lesley Stahl, in reference to years of U.S.-led economic sanctions against Iraq, "We have heard that half a million children have died. I mean, that is more children than died in Hiroshima. And, you know, is the price worth it?"

To which Ambassador Albright responded, "I think that is a very hard choice, but the price, we think, the price is worth it."

So, is there somebody at the top who thinks that stockpiling nuclear weapons is a good thing for planetary defense of a cosmic nature?

There is another way to ask the question: are the Powers That Be using the threat of asteroids on lawmakers to get them to agree to backing the phony War on Terror in order to obtain and retain the support of the masses when what they are really doing is just planning on a fascist take-over of the world? Notice that the paper above also said:

The risk of diversion of any mitigation system to military uses must be regarded as a more immediate hazard.

It's hard to tell what goes on in the minds of deviants. One thing I think we can be sure of is that the threat of cometary bombardment is real and immediate, and that comes from the science. Sadly, it does not come from our leaders who, even if they are aware of some threat and are stockpiling nuclear weapons to use to divert inbound asteroids or comets, haven't bothered to make the threat clear to the masses of humanity via science as they very well could.

Scanning through this almost 1300 page volume which collects pretty much all the then scientifically acknowledged data on comet and asteroid impacts reveals that there was some pretty interesting thinking going on prior to Shoemaker-Levy 9. We've come a long way in our understanding since then; well, some have. The U.S. school is still pretty much stuck in the "single massive asteroid at vast timescales"; probably due to political pressures to keep the real issues covered up. I noted that Shoemaker had a paper in the volume where he said there were only 140 known impact craters on the earth. He completely ignored the Carolina bays which have been reclaimed for what they are by Richard Firestone, Allen West and Simon Warwick-Smith in The Cycle of Cosmic Catastrophes: Flood, Fire, and Famine in the History of Civilization. I understand that there are over 50,000 of those critters. That's scary!

We also note the remark in the above paper: "The frequency of impacts of objects of various sizes is known only to limited precisions. In particular, objects up to several meters in diameter explode in the atmosphere without reaching the surface." Obviously, this guy wasn't part of the the same crowd that hung out with Brigadier General S. Pete Worden, who said that he believes "we should pay more attention to the 'Tunguska-class' objects - 100 meter or so objects which can strike up to several times per century with the destructiveness of a nuclear weapon," reported in the previous article: Thirty Years of Cults and Comets.

In any event, the authors of the above quoted paper had a generally open attitude toward the public and educating them that no longer seems to be the perception of our ruling elites.

Speaking of General Worden and his obscure remark, after publishing the last installment of the present series, several members of the SOTT Forum did a little digging on the question and came up with some very interesting finds. It seems that there were two events in the 1930s that equalled the Tunguska event:

Two "Tunguskas" in South America in the 1930's?
This article was printed in IMO's December 1995 edition of the WGN Journal. It was written by Duncan Steel of the Anglo-Australian Observatory.

There is evidence that there were two massive bolide explosions which occurred over South America in the 1930's. One seems to have occurred over Amazonia, near the Brazil-Peru border, on August 13, 1930, whilst the other was over British Guyana on December 11, 1935. It is noted that these dates coincide with the peaks of the Perseids and the Geminids, although any association with those meteor showers is very tentative. The identification of such events is significant in particular in that they point to the need for re-assessment of the frequency of tunguska-type atmospheric detonations.

Then there is this:

February 12, 1947: A rain of around 70 tons of iron

This week marks the golden anniversary of what is arguably the most spectacular meteorite fall ever seen. At 10:40 a.m. on February 12, 1947, a incredibly bright fireball seared its way across the sky of eastern Siberia and rained around 70 tons of iron meteorites onto the rugged landscape. Because it was so well documented, the Sikhote-Alin fall proved a great boon to meteorite science.

The 1947 Siberian event is considered in most literature as one of the two most significant events this century where the earth has encountered objects from space. It was an iron meteorite that broke up only about 5 miles above the earth. It produced over 100 craters with the largest being around 85 feet in diameter. The strewnfield covered an area of about 1 mile by a half mile. There were no fires or similar destruction like that found at Tunguska. Shredded trees and broken branches mostly. A total of 23 tons of meteorites were recovered and it's been estimated it's total mass was around 70 tons when it broke up.

(from Sky Publishing Corporation and George Zay)

There are more, of course, but this just tells us that there are many things going on here on the Big Blue Marble that we aren't aware of. That's what Victor Clube is saying in his narrative report to the USAF and Oxford that sent me off on this topic. So, let's return to Clube and our historical review:

The next period of cometary activity that Clube refers to is that which encompassed the American Revolution (1775 - 1783) and the French Revolution (1789 - 1799) and the mid-nineteenth century crisis. I'm going to skip the two revolutions for the moment and go directly to the mid-nineteenth century period because it is intensely interesting and leads us into our topic of the day.

In trying to find some details about the mid-nineteenth century crisis mentioned above, a whole lot of things turned up that I'm sure we all learned in history class in school, but it just never was put together in a way that made it look as interesting as it does now! What happened then was, of course, the "Industrial Revolution." But it was kind of like the Renaissance in that it overlapped a lot of other interesting events.

The Industrial Revolution and the rise of capitalism began, more or less, toward the end of the eighteenth century. The nineteenth century was a turbulent epoch beginning with a stock market crash in 1825 then moving on to the Panic of 1847, a collapse of British financial markets associated with the end of the 1840s railroad boom. The crisis of 1847 could have been more disastrous except that it was cut short by economic revival following the California gold strike of 1849.

After a period of prosperity, there began a series of wars and revolutions. There was the first Italian War for Independence in 1857, and then the American Civil War of 1861, the Polish Insurrection of 1863, Napoleon the Second's Mexican adventure and the campaign against Denmark in 1864 which started the Prussian Wars led by Bismarck. Bismarck attacked Austria in 1866 and won a victory over France in 1871. The, there was the Republican uprising in Spain which toppled Queen Isabella from the throne. Finally, there was the last of Louis Napoleon's adventures which culminated in the crashing of the Empire in 1871.

There was Civil War in France following the downfall of the Second Napoleon, and the people (Paris Communards) seized power. They were soon crushed and order was restored in the Third Republic, and the revolutionary tide receded for the rest of the century.

It is interesting to consider the other events that were occurring at this time. Industrial capitalism was being spread with missionary zeal everywhere. Western investors roamed the globe looking for openings to establish trade and to invest in anything that could be bought or sold. In the process, millions of people were redistributed in the greatest mass migrations in history from the Old World to the New. Science became the handmaiden of industry and capitalism. The volume of world trade was 1.75 billion dollars in 1830 and it rose to 3.6 billion in 1850, skyrocketing to 9.4 billion in 1870.

So, Clube is right. For about twenty-five years, the entire Western world was bubbling cauldron of war and revolution and people taking advantage of wars and revolution to make money. When it was all over, the imperial powers of Europe that were to rule the world until 1914, were firmly ensconced. More than that, the United States as a federal, capitalist entity, had been forged at Appamattox.

There were obviously other things going on at that time. In the period from 1830 to 1860 there was apparently an enormous upsurge in religious fervor. The imminent return of Christ was being predicted everywhere! Manuel de Lacunza, a Catholic priest in South America wrote (under the pen name of Juan Josafa Ben-Ezra) a book entitled The Coming of Messiah in Glory and Majesty, which was published in Spain in 1812. He believed that Jesus was coming very, very soon. William Miller (Seventh-Day Adventists) declared that Christ was coming and predicted 1844 as the date. Edward Irving of England and Johann Bengel in Germany almost simultaneously came to the conclusion that the prophecies of Daniel pointed to the time of the end being right then; Mason in Scotland, Leonard H. Kelber in Germany and many, many others preached about the Second coming. Spiritualist Andrew Jackson Davis gave 157 lectures in 1845 about the new era, which Edgar Allen Poe attended regularly. The Spiritualism Craze began with the Fox sisters in 1848. Mourant Brock, of the Church of England, noted that the craze for eschatology had spread through all of Europe and extended to India. (See: The Story of Prophecy by Henry James Forman).

As Clube notes, this religious fervor parallels cosmic events.

In 1843, there appeared one of the greatest comets of history. The Great Comet of 1843 formally designated C/1843 D1 and 1843 I, was discovered on February 5, 1843 and rapidly brightened. It was a member of the Kreutz Sungrazers, a family of comets resulting from the breakup of a parent comet (X/1106 C1) into multiple fragments in about 1106. These comets pass extremely close to the Sun - within a few solar radii - and this is why they often become very bright.

C/1843 D1 moved rapidly toward an incredibly close perihelion of less than 830,000 km on February 27, 1843, at which time it could be seen in broad daylight just a degree away from the Sun! It swung around and passed close to earth on March 6, 1843, and seemed to manifest its greatest brilliance the following day. It was last observed on April 19, 1843. At that time this comet had passed closer to the sun than any other known object. The American Journal of Science and The New York Tribune devoted special sections to this comet at the time. You could say that "comet fever" was pandemic!

The Great Comet of 1843 - still unnamed - developed a tail over 2 Astronomical Units in length, the longest known cometary tail until measurements in 1996 showed that Comet Hyakutake's tail was almost twice as long.

In 1857, an anonymous German astrologer predicted that a comet would strike the earth on June 13 of that year. The impending catastrophe became the talk of all of Europe. The French astronomer, Jacques Babinet, tried to reassure people by stating that a collision between the earth and a comet would do no harm. He compared the impact to "a railway train being hit by a fly". His words, apparently, had little effect. The Paris correspondent for the American journal, Harper's Weekly, wrote:

Women have miscarried; crops have been neglected; wills have been made; comet-proof suits of clothing have been invented; a cometary life insurance company (premiums payable in advance) has been created... all because an almanac maker... thought proper to insert, under the week commencing June 13, 'About this time, expect a comet'.

Let's back up just a minute here, to 1826. In 1826, comet 3D/Biela was discovered by Wilhelm von Biela. It has become known as Comet Biela or Biela's Comet. This comet had been first seen in 1772 by Charles Messier and again in 1805 by Jean-Louis Pons. It was von Biela who discovered it in its 1826 perihelion approach (on February 27) and calculated its orbit, discovering it to be periodic with a period of 6.6 years which is why it was named after him and not Messier or Pons. It was only the third comet (at the time) found to be periodic, after the famous comets Halley and Encke. French astronomer M. Damoiseau subsequently calculated its path, and announced that on its next return the comet would cross the orbit of the earth, within twenty thousand miles of its track, and about one month before the earth would arrive at the same spot!

When the comet came in 1832, the earth did, indeed, miss it by one month. It returned again in 1839 and 1846. In its 1846 appearance, the comet was observed to have broken up into two pieces. It was observed again in 1852 with the two parts being 1.5 million miles apart. Each part had a head and tail of its own.

©Unknown

The comet did not come in 1852, 1859, or 1866. The Edinburgh Review notes about this strange state of affairs:

The puzzled astronomers were left in a state of tantalizing uncertainty as to what had become of it. At the beginning of the year 1866 this feeling of bewilderment gained expression in the Annual Report of the Council of the Royal Astronomical Society. The matter continued, nevertheless, in the same state of provoking uncertainty for another six years. The third period of the perihelion passage had then passed, and nothing had been seen of the missing luminary. But on the night of November 27, 1872, night-watchers were startled by a sudden and a very magnificent display of falling stars or meteors, of which there had been no previous forecast... [source]

The meteors were radiating from the part of the sky where the comet had been expected to cross in September. In other words, the trajectory was the same, and the earth intersected it, but the velocity was somewhat altered. The American Journal of Science said they fell like snowflakes. Professor Olmstead, a mathematician at Yale University estimated 34,640 shooting stars per hour. The New York Journal of Commerce wrote that no philosopher or scholar has ever recorded an event like this. These meteors became known as the Andromedids or "Bielids" and it seems apparent that they indicated the death of the comet. The meteors were seen again on subsequent occasions for the rest of the 19th century, but have now faded away.

Is that all there is to that?

Maybe not.

As it happens, on Sunday, the 8th of October, in the year 1871, at half past nine o'clock in the evening, events occurred which caused the death of hundreds of human beings, and the destruction of vast amounts of property, across three different States of the American Union, sending millions of people into fits of the wildest alarm and terror. The following passages are extracted from the History of the Great Conflagration, Sheahan & Upton, Chicago 1871. [source]

The summer of 1871 had been excessively dry; the moisture seemed to be evaporated out of the air; and on the Sunday above named the atmospheric conditions all through the Northwest were of the most peculiar character. The writer was living at the time in Minnesota, hundreds of miles from the scene of the disasters, and he can never forget the condition of things. There was a parched, combustible, inflammable, furnace-like feeling in the air, that was really alarming. It felt as if there were needed but a match, a spark, to cause a world-wide explosion. It was weird and unnatural. I have never seen nor felt anything like it before or since. Those who experienced it will bear me out in these statements.

At that hour, half past nine o'clock in the evening, at apparently the same moment, at points hundreds of miles apart, in three different States, Wisconsin, Michigan, and Illinois, fires of the most peculiar and devastating kind broke out, so far as we know, by spontaneous combustion.

In Wisconsin, on its eastern borders, in a heavily timbered country, near Lake Michigan, a region embracing four hundred square miles, extending north from Brown County, and containing Peshtigo, Manistee, Holland, and numerous villages on the shores of Green Bay, was swept bare by an absolute whirlwind of flame. There were seven hundred and fifty people killed outright, besides great numbers of the wounded, maimed, and burned, who died afterward. More than three million dollars' worth of property was destroyed. (pp 393, 394, etc.)

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"At sundown there was a lull in the wind and comparative stillness. For two hours there were no signs of danger; but at a few minutes after nine o'clock, and by a singular coincidence, precisely the time at which the Chicago fire commenced, the people of the village heard a terrible roar. It was that of a tornado, crushing through the forests. Instantly the heavens were illuminated with a terrible glare. The sky, which had been so dark a moment before, burst into clouds of flame.

A spectator of the terrible scene says the fire did not come upon them gradually from burning trees and other objects to the windward, but the first notice they had of it was a whirlwind of flame in great clouds from above the tops of the trees, which fell upon and entirely enveloped everything. The poor people inhaled it, or the intensely hot air, and fell down dead. This is verified by the appearance of many of the corpses. They were found dead in the roads and open spaces, where there were no visible marks of fire near by, with not a trace of burning upon their bodies or clothing. At the Sugar Bush, which is an extended clearing, in some places four miles in width, corpses were found in the open road, between fences only slightly burned. No mark of fire was upon them; they lay there as if asleep. This phenomenon seems to explain the fact that so many were killed in compact masses. They seemed to have huddled together, in what were evidently regarded at the moment the safest places, far away from buildings, trees, or other inflammable material, and there to have died together. (p. 372)

Another spectator says:

"Much has been said of the intense heat of the fires which destroyed Peshtigo, Menekaune, Williamsonville, etc., but all that has been said can give the stranger but a faint conception of the reality. The heat has been compared to that engendered by a flame concentrated on an object by a blow-pipe; but even that would not account for some of the phenomena. For instance, we have in our possession a copper cent taken from the pocket of a dead man in the Peshtigo Sugar Bush, which will illustrate our point. This cent has been partially fused, but still retains its round form, and the inscription upon it is legible. Others, in the same pocket, were partially melted, and yet the clothing and the body of the man were not even singed. We do not know in what way to account for this, unless, as is asserted by some, the tornado and fire were accompanied by electrical phenomena" (373).

"It is the universal testimony that the prevailing idea among the people was, that the last day had come. Accustomed as they were to fire, nothing like this had ever been known. They could give no other interpretation to this ominous roar, this bursting of the sky with flame, and this dropping down of fire out of the very heavens, consuming instantly everything it touched.

"No two give a like description of the great tornado as it smote and devoured the village. It seemed as if 'the fiery fiends of hell had been loosened,' says one. 'It came in great sheeted flames from heaven,' says another. 'There was a pitiless rain of fire and *sand*.' 'The atmosphere was all afire.' Some speak of 'great balls of fire unrolling and shooting forth in streams.' The fire leaped over roofs and trees, and ignited whole streets at once. No one could stand before the blast. It was a race with death, above, behind, and before them" (Ibid 374).

A civil engineer, doing business in Peshtigo, says:

"The heat increased so rapidly, as things got well afire, that, when about four hundred feet from the bridge and the nearest building, I was obliged to lie down behind a log that was aground in about two feet of water, and by going under water now and then, and holding my head close to the water behind the log, I managed to breathe. There were a dozen others behind the same log. If I had succeeded in crossing the river and gone among the buildings on the other side, probably I should have been lost, as many were."

In Michigan, one Allison Weaver, near Port Huron, determined to remain, to protect, if possible, some mill-property of which he had charge. He knew the fire was coming, and dug himself a shallow well or pit, made a thick plank cover to place over it, and thus prepared to bide the conflagration. I quote:

"He filled it nearly full of water, and took care to saturate the ground around it for a distance of several rods. Going to the mill, he dragged out a four-inch plank, sawed it in two, and saw that the parts tightly covered the mouth of the little well. 'I calculated it would be touch and go,' said he, 'but it was the best I could do.' At midnight he had everything arranged, and the roaring then was awful to hear. The clearing was ten to twelve acres in extent, and Weaver says that, for two hours before the fire reached him, there was a constant flight across the ground of small animals. As he rested a moment from giving the house another wetting down, a horse dashed into the opening at full speed and made for the house. Weaver could see him tremble and shake with excitement and terror, and felt a pity for him. After a moment, the animal gave utterance to a snort of dismay, ran two or three times around the house, and then shot off into the woods like a rocket."

"Not long after this the fire came. Weaver stood by his well, ready for the emergency, yet curious to see the breaking-in of the flames. The roaring increased in volume, the air became oppressive, a cloud of dust and cinders came showering down, and he could see the flame through the trees. It did not run along the ground, or leap from tree to tree, but it came on like a tornado, a sheet of flame reaching from the earth to the tops of the trees. As it struck the clearing he jumped into his well, and closed over the planks. He could no longer see, but he could hear. He says that the flames made no halt whatever, or ceased their roaring for an instant, but he hardly got the opening closed before the house and mill were burning tinder, and both were down in five minutes. The smoke came down upon him powerfully, and his den was so hot he could hardly breathe.

"He knew that the planks above him were on fire, but, remembering their thickness, he waited till the roaring of the flames had died away, and then with his head and hands turned them over and put our the fire by dashing up water with his hands. Although it was a cold night, and the water had at first chilled him, the heat gradually warmed him up until he felt quite comfortable. He remained in his den until daylight, frequently turning over the planks and putting out the fire, and then the worst had passed. The earth around was on fire in spots, house and mill were gone, leaves, brush, and logs were swept clean away as if shaved off and swept with a broom, and nothing but soot and ashes were to be seen" (390).

In Wisconsin, at Williamson's Mills, there was a large but shallow well on the premises belonging to a Mr. Boorman. The people, when cut off by the flames and wild with terror, and thinking they would find safety in the water, leaped into this well.

"The relentless fury of the flames drove them pell-mell into the pit, to struggle with each other and die - some by drowning, and others by fire and suffocation. None escaped. Thirty-two bodies were found there. They were in every imaginable position; but the contortions of their limbs and the agonizing expressions of their faces told the awful tale". (386)

James B. Clark, of Detroit, who was at Uniontown, Wisconsin, writes:

"The fire suddenly made a rush, like the flash of a train of gunpowder, and swept in the shape of a crescent around the settlement. It is almost impossible to conceive the frightful rapidity of the advance of the flames. The rushing fire seemed to eat up and annihilate the trees."

They saw a black mass coming toward them from the wall of flame:
"It was a stampede of cattle and horses thundering toward us, bellowing, moaning, and neighing as they galloped on; rushing with fearful speed, their eyeballs dilated and glaring with terror, and every motion betokening delirium of fright. Some had been badly burned, and must have plunged through a long space of flame in the desperate effort to escape.

Following considerably behind came a solitary horse, panting and snorting and nearly exhausted. He was saddled and bridled, and, as we first thought, had a bag lashed to his back. As he came up we were startled at the sight of a young lad lying fallen over the animal's neck, the bridle wound around his hands, and the mane being clinched by the fingers. Little effort was needed to stop the jaded horse, and at once release the helpless boy. He was taken into the house, and all that we could do was done; but he had inhaled the smoke, and was seemingly dying. Some time elapsed and he revived enough to speak. He told his name - Patrick Byrnes - and said: 'Father and mother and the children got into the wagon. I don't know what became of them. Everything is burned up. I am dying. Oh! Is hell any worse than this?'" (383)

When we leave Wisconsin and pass about two hundred and fifty miles eastward, over Lake Michigan and across the whole width of the State of Michigan, we find much the same condition of things, but not so terrible in the loss of life. Fully fifteen thousand people were rendered homeless by the fires; and their food, clothing, crops, horses, and cattle were destroyed. Of these five to six thousand were burned out the same night that the fires broke out in Chicago and Wisconsin. The total destruction of property exceeded one million dollars; not only villages and cities, but whole townships, were swept bare.

But it is to Chicago we must turn for the most extraordinary results of this atmospheric disturbance. It is needless to tell the story in detail. The world knows it by heart. I have only space to refer to one or two points,

The fire was spontaneous. The story of Mrs. O'Leary's cow having started the conflagration by kicking over a lantern was proved to be false. It was the access of gas from the tail of Biela's comet that burned up Chicago!

The fire-marshal testified: "I felt it in my bones that we were going to have a burn." He says, speaking of O'Leary's barn:

"We got the fire under control, and it would not have gone farther; but the next thing I knew they came and told me that St. Paul's church, about two squares north, was on fire". (163)

They checked the church-fire, but - "The next thing I knew the fire was in Bateham's planing-mill."

A writer in the New York Evening Post says he saw in Chicago "buildings far beyond the line of fire, and in no contact with it, burst into flames from the interior."

It must not be forgotten that the fall of 1871 was marked by extraordinary conflagrations in regions widely separated. On the 8th of October, the same day the Wisconsin, Michigan, and Chicago fires broke out, the States of Iowa, Minnesota, Indiana, and Illinois were severely devastated by prairie-fires; while terrible fires raged on the Alleghenies, the Sierras of the Pacific coast, and the Rocky Mountains, and in the region of the Red River of the North.

The Annual Record of Science and Industry for 1876, page 84, says:

"For weeks before and after the great fire in Chicago in 1872, great areas of forest and prairie-land, both in the United States and the British Provinces, were on fire."

The flames that consumed a great part of Chicago were of an unusual character and produced extraordinary effects. They absolutely melted the hardest building-stone, which had previously been considered fire-proof. Iron, glass, granite, were fused and run together into grotesque conglomerates, as if they had been put through a blast-furnace. No kind of material could stand its breath for a moment.

I quote again from Sheahan & Upton's work:

"The huge stone and brick structures melted before the fierceness of the flames as a snow-flake melts and disappears in water, and almost as quickly. Six-story buildings would take fire and disappear for ever from sight in five minutes by the watch... The fire also doubled on its track at the great Union Depot and burned half a mile southward in the very teeth of the gale - a gale which blew a perfect tornado, and in which no vessel could have lived on the lake... Strange, fantastic fires of blue, red, and green played along the cornices of buildings" ["History of the
Chicago Fire" 85, 86].

Hon. William B. Ogden wrote at the time:

"The fire was accompanied by the fiercest tornado of wind ever known to blow here" [Ibid 87].

"The most striking peculiarity of the fire was its intense heat. Nothing exposed to it escaped. Amid the hundreds of acres left bare there is not to be found a piece of wood of any description, and, unlike most fires, it left nothing half burned... The fire swept the streets of all the ordinary dust and rubbish, consuming it instantly" [Ibid 119].

The Athens marble burned like coal!

"The intensity of the heat may be judged, and the thorough combustion of everything wooden may be understood, when we state that in the yard of one of the large agricultural-implement factories was stacked some hundreds of tons of pig-iron. This iron was two hundred feet from any building. To the south of it was the river, one hundred and fifty feet wide. No large building but the factory was in the immediate vicinity of the fire. Yet, so great was the heat, that this pile of iron melted and run, and is now in one large and nearly solid mass" [Ibid 121].

The amount of property destroyed was estimated by Mayor Medill at one hundred and fifty million dollars; and the number of people rendered houseless, at one hundred and twenty-five thousand. Several hundred lives were lost.

"What eyewitnesses described was more like a holocaust from heaven than an accidental fire started by a nervous cow. And in fact, according to a theory propounded by Minnesota Congressmen Ignatius Donnelly, the devastating fires of 1871 did fall from above, in the form of a wayward cometary tail. During it's 1846 passage, Biela's comet had inexplicably split in two; it was supposed to return in 1866, but failed to appear. Biela's fragmented head finally showed up in 1872 as a meteor shower.

"Donnelly suggested the separated tail appeared in 1871 and was the prime cause of the widespread firestorm that swept the Midwest, damaging or destroying a total of twenty-four towns and leaving 2,000 or more dead in its wake. Drought conditions that fall no doubt contributed to the extent of the conflagration.

"History today concentrates on the Chicago Fire alone and largely overlooks the Peshtigo Horror, as it was then called. It ignores altogether Biela's comet and it's unaccounted-for tail. (Ken Rieli)

No doubt that this story came to the attention of Victor Clube!

Ten years later, there was the Great Comet of 1881 (C/1881 K1), discovered by the Australian amateur astronomer, John Tebbutt. All we hear about this comet nowadays is that it was one of the first comets photographed and studied scientifically. However, this comet following so closely on the events of ten years previously obviously got a few people thinking.

Ignatius Donnelly, who had already stated that he thought the Great Chicago Fire had been caused by cometary debris, published a book in 1882, entitled Ragnarok, wherein he proposed that a giant comet had passed close to the earth in past ages. The intense heat from the comet had set off huge fires that raged across the face of the globe. He suggested that the comet had dumped vast amounts of dust on the earth, triggered earthquakes, leveled mountains, and initiated the ice age. He even explained some of the miracles of the Bible in terms of his comet, proposing that the standing-still of the sun at the command of Joshua was possibly a tale commemorating this event. Donnelly's readers were thrilled by his descriptions of the "glaring and burning monster" in the sky, scorching the planet with unearthly heat and shaking the land with "thunders beyond all thunders".

Possibly inspired by Donnelly (not to mention what was obviously going on in the heavens), Camille Flammarion wrote The End of the World in 1893 in which he recounted a fictional collision between the earth and a comet fifty times its size. Flammarion's lurid prose ensured that his book was an immediate sensation! (Flammarion, it should be noted, was a friend and associate of, and greatly influenced by, Allan Kardec, the French Pedagogue, medical student, linguist and researcher of "spirit communications." He was also a friend of Jules Violle the probable true identity of the legendary alchemist, Fulcanelli.)

Well, all that was a pretty interesting diversion into history, now wasn't it? Doesn't seem quite so dull and boring anymore, eh? Okay, time to return to Victor Clube's narrative. I think that what he is writing will make a whole lot more sense now!

The fact of a perceived danger at these epochs, signified historically by a global rise in eschatological concern, is now understood in various academic quarters as marking some kind of physical dislocation (climate? disease?) which causes economic and social activity to be widely deranged, even to the point of collapse of civilized society, leading then to revolution, mass migration and war, amplified on a global scale. The occasions of such breakdowns in civilization are of course a matter of serious concern and their systematic study has been taken up in America (and elsewhere) at such institutes as the Center for Comparative Research in History, Society and Culture at the University of California, Davis (Goldstone, 1991). To the "enlightened" however, the eschatology remains an anomaly and secure connections with celestial inputs have generally still to be made. We should recall however that many, as usual on these occasions of breakdown, would see "blazing stars threatening the world with famine, plague and war; to princes' death; to kingdoms many curses; [and] to all estates many losses..."

The three earliest of these epochs are of course the periods of Inquisition and of the great European witch-hunts (which spilled over to America) when ecclesiastical and secular administrators alike would discourage any (astrological) notion that the celestial sphere interfered with terrestrial affairs. The separate stories of scientific revolutionaries like Copernicus, Kepler, Bruno, Galileo and Newton now bear witness to the ferocity with which the most acceptable cosmic viewpoint (of the time) was imposed. Indeed, these separate stories are still being adjusted and Newton, it is now realised, was constrained by his times to work under conditions of rather considerable censorship.

The acceptable part of his scientific output was of course published and has proved its worth repeatedly over 300 years. The unacceptable part however dealt with "blazing stars" and eschatology and remained unpublished for some 250 years. One of the first to examine this material (Keynes 1947) was so taken aback by the contrast as to dub Newton not so much "the first of the age of reason" as "the last of the magicians, the last of the Babylonians and Sumerias". Thus it was the Founding Fathers of the Royal Society in Restoration England who hit upon the "enlightened" step of deriding the cosmic threat and public anxiety; and it is not without significance today that English-speaking nations ultimately stood firm and prospered as others faltered at the last and briefest of the above epochs (Goldstone, loc cit). Accordingly, it is largely an Anglo-Saxon "achievement" that cosmic catastrophes were absolutely discarded and the scientific principle of uniformitarianism was put in place between 200 and 150 years ago.

If short-period bombardment of our planet by comets or comet dust is a reality (as it increasingly appears to be); and the effects of such an event are deleterious in the extreme; and if we are in fact overdue for a repeat performance of such a visitation (which also appears to be the case); what effect might public awareness of this have on the status quo on the planet at present? Would the bogus "war on terror" not become instantly obsolete and would people across the planet not immediately demand that their political leaders reassess priorities and take whatever action possible to mitigate the threat? And if those political leaders refused to do so and it became known that that this grave threat to the lives of billions was long-standing and common knowledge among the political elite (with all that that implies), what then? Revolution? One last hurrah before the 6th extinction?

Who knows. We only know that this knowledge, in its fullest explication, is being suppressed and marginalized. The reasons for the psychological games and ploys may be interesting to investigate. so that is what we will look at next: Why is Humanity so Deaf, Dumb and Blind?

Argentina: Fireball possible cause of fires in Las Ánimas Hill 

Radiotandil
Tue, 05 Feb 2008 17:24 EST

Last night several witnesses reported to the program Última Hora that a "UFO" that fell at 4:00 am behind Las Ánimas Hill could have been the cause of the enormous and devastating fire that affected hundreds of hectares.

"It was like a huge fire ball that fell behind the hill", said a neighbor, whose report was confirmed by others.

A Ronicevi metallurgic worker, whose shift began at 4:00 am, said that the UFO gave off an intense glow and its size was similar to the moon in its full phase.

As of midnight last night, the authorities had neither confirmed the origin of the fires nor found the remains of the object that was seen by the neighbors.

Nevertheless, official sources stated that last Monday's fire was caused by the re-ignition of the previous day's fire, which was initially reported to be under control.

Translation by Signs of the Times

The goose that survived crashing into a meteorite only to be savaged by a fox! 

Asian News International
Wed, 06 Feb 2008 14:03 EST

A goose survived being hit by a 9lb meteorite and crashing into a car only to fall prey to a hungry fox.

And, witness to all this was Brit postman Adrian Mannion who was enjoying his morning cup of tea with wife Fiona when the bizarre set of events unfolded.

According to Mannion, the Canada Goose was left dazed when after banging into a meteorite, it fell headlong into his cars roof, causing 2,500 pounds worth of damage.

However, there was no reprieve for the bird, for a hungry fox then grabbed it dragged it away before the Mannions could rescue it.

We heard two almighty thuds and rushed out to see this large, odd-looking rock next to our Mini and a very poorly-looking mangled goose on the car roof, The Sun quoted Mr Mannion, as saying.

A flock of Canada Geese were overhead so the falling stone must have hit the poor creature.

Mrs Mannion added: It has to be the unluckiest bird ever. It survived being knocked out by a meteorite only to be savaged by a fox.

The meteorite is now being studied by researchers at the University of Derby. It is one of only 1,000 asteroid fragments that hit earth each year.

Kamikaze comet ripples Saturn's ring

David Shiga
space.newscientist.com
Wed, 06 Feb 2008 23:51 EST

A smack from a small comet in the 1980s may be responsible for ripples in one of Saturn's rings, images from NASA's Cassini spacecraft suggest. The finding is another indication that the rings are not static and can change on human timescales.

Cassini observations have revealed bright and dark bands in Saturn's innermost ring, called the D ring. The bands are getting more closely spaced as time goes on - Hubble Space Telescope images reveal they were 60 kilometres apart in 1995 and Cassini shows they have been shrinking over the last few years and are just 30 km apart now.

©NASA/JPL/Space Science Institute

The edge of the D ring is seen at the centre of this image, showing a banded structure that has gradually became more finely spaced since it was first detected by Hubble in 1995

The Cassini observations suggest that the D ring is not perfectly flat but has small vertical hills and valleys, like grooves in a record. The deviations from perfect flatness are just a kilometre in height, while the ring itself is about 140,000 kilometres across.

Sunlight reflected from these ripples is thought to create bright bands where it hits a relatively large amount of material and dark bands where it hits a smaller amount (see illustration).

The gradual narrowing of the bands has been a puzzle to Cassini scientists, but a new analysis suggests it is the result of an object, perhaps a very small comet, hitting the rings in the 1980s.
Cascade of collisions

Researchers led by Matthew Hedman of Cornell University in Ithaca, New York, US, modelled what would happen if a body a few metres across and travelling at a few dozen kilometres per second struck one of the icy chunks that makes up the D ring.

"They would both shatter and send a plume of material into the rings," Hedman says. The fragments from this collision would in turn collide with other particles in the ring, creating a cascade of collisions. After all of these collisions, the ring would end up tilted with respect to Saturn's equator.

This configuration is unstable, however. A computer model developed by the team shows that Saturn's gravity starts twisting and deforming the tilted ring, creating a rippled spiral. As time goes on, this spiral winds up tighter and tighter until it looks like a grooved record, just as the D ring appears today.

Using the model, the team calculated that the collision would have needed to occur in 1984 to reproduce the ring's appearance today. "This is just further evidence showing that these rings really are dynamic objects," Hedman says. "They're not eternal structures."

Hedman presented the results at a meeting of the American Astronomical Society's Division for Planetary Sciences in Pasadena, California, US.

Asteroid Flyby: That was close! 

Spaceweather.com
Wed, 06 Feb 2008 18:35 EST

Yesterday, newly discovered asteroid 2008 CT1 flew past Earth only 72,000 miles (0.3 lunar distances) away. Had it struck our planet, the 13-meter wide space rock (similar in size to a school bus) would have done little damage, probably exploding in the atmosphere and peppering some lonely stretch of ocean with meteorites. Maybe next time...

Ice Chunks Crash Through Woman's Ceiling 

Associated Press
Fri, 08 Feb 2008 18:16 EST

A Canadian woman narrowly avoided getting hit by several chunks of ice that crashed through her bedroom ceiling Thursday, likely dropped from a passing airplane, officials said.

The Calgary, Alberta fire department said the woman was in her room and only a few steps away when debris "exploded" through her roof shortly before 9:30 a.m..

Fire crews found several chunks of ice about 6 inches long on the bed, along with pieces of shingles, plywood, drywall and insulation.

Fire department spokesman Jeff Budai said his best guess is that the "frozen liquid" fell from a passing airplane.

The Transportation Safety Board of Canada is looking into the incident and confirms that a couple of airplanes were in the area at the time.

Texas residents rattled, but by what? 

Peggy Heinkel-Wolfe
Denton Record Chronicle
Fri, 08 Feb 2008 07:26 EST

Denton County sheriff's dispatchers received nine calls from residents between 11:45 and 11:51 p.m. asking whether the shaking was an earthquake, a sonic boom, an explosion or something else altogether.

The earth moved Tuesday night for many Denton-area residents, but what caused it remains a mystery.

"I was laying in bed, reading a book when it happened. It seemed like a loud noise and the whole house shook for a second or two," said Susan Seaborn of Corinth.

She looked at her watch when the windows rattled. It read 11:34 p.m.

"But my husband said, 'I don't remember a bang.'"

Seaborn said she felt another bump a few minutes later, although her husband said he didn't feel that either.

The couple looked around their house and found no damage, but they did find their neighbors outside doing the same thing. Their neighbors thought a tree had fallen on their roof.

Denton County sheriff's dispatchers received nine calls from residents between 11:45 and 11:51 p.m. asking whether the shaking was an earthquake, a sonic boom, an explosion or something else altogether.

University of Texas professor Cliff Frohlich, an expert on Texas earthquakes, said that he, too, received calls from Denton-area residents curious whether what they felt was an earthquake.

There were no reports from the National Earthquake Information Center, but that seismic data is limited to quakes that register magnitude 3 or more on the Richter scale, Frohlich said.

"And that would be felt across the state," Frohlich said.

A seismograph in Hockley, north of Houston, showed no activity either, but a small tremor, measuring 2 or less on the Richter scale, would be felt only locally. Such a quake could be measured only if there were instruments in the area, he said.

The most recent measurable earthquake in North Texas shook Commerce on May 13, 1997, with a 2.9 magnitude temblor. The nearest quake shook Valley View on Sept. 18, 1985, measuring 3.3 on the Richter scale. The biggest quake in North Texas was centered just north of Paris and measured 4.2 back in 1934, Frohlich said.

The biggest quakes on record in the nation's midsection occurred in Missouri in 1811 and 1812. Based on damage reports, experts estimate those quakes measured about 8 on the Richter scale.

The kinds of reports people have made about Monday night's shake are consistent with a temblor of 2 or less, Frohlich said.

"People report a loud noise or a jolt. They hear them more than they feel them," Frohlich said.

But, he said, the reports are also consistent with other earth-shaking events, such as storms and sonic booms.

Jody Gonzalez, Denton County emergency management coordinator, said that the southwestern corner of the county is in a Fort Worth-Wichita Falls flight path where pilots are allowed to fly their craft at supersonic speeds.

If an airplane does pass the speed-of-sound barrier, the boom could be felt anywhere in the county, depending on the wind, Gonzalez said. But emergency management officials aren't typically told when such a flight has come through.

"We never know," he said.

Fireball Over Polk County

LiveLeak
Thu, 07 Feb 2008 15:24 EST

Polk County, FL -- A Polk County man videotapes a strange fireball in the sky over Polk County. Rhett Marcotes and his family saw the phenomenon on January 7th just before dusk outside his home in Davenport. Marcotes and his wife grabbed their video camera and began filming. The results were stunning.

©LiveLeak

Marcotes says they couldn't figure out what it was. The filmed it for about nine minutes until it passed the tree line. They showed the tape to co-workers, friends, and family. Marcotes says everyone has a theory to the fireball over Polk County. Some said space junk, others said meteors, and some even said it was aliens.

Marcotes and his family weren't the only ones to see the fireball. Several people called 9-1-1 in Polk County to report the fire in the sky. The sheriff's office provided us copies of the tapes and you can hear them here.

We took the tape to two professors at Florida Southern College in Lakeland. That's about 30 miles from where Marcotes saw the fireball. Doctors Mossayeb Jamshid and Peter Bias say they don't believe the video shows a celestial event. They say the contrail and brightness suggest jets or engines of some sort enormously high in the atmosphere.

We also showed a copy to Stephen Nipper. He's the Manager of Planetarium and Senior Programs at the Museum of Science and Industry in Tampa.

Steve Nipper- Museum of Science and Industry:
"This video is a good example of how an ordinary object, under slightly unusual viewing conditions can present a spectacular visual (and video) image. It is definitely a condensation trail, or contrail, from a jet aircraft. There were no re-entries of space debris on that day, and no reports which
I could find in the scientific or aeronautical communities of a significant meteor entry. "

"In addition, at around 6 minutes into the video, there is a second, fainter and lower, but similar object crossing the field of view perpendicular to the path of the first object.
Also, the duration of the sighting indicates that the object was moving at a slow speed in comparison to a meteor or orbiting space debris. The speed at which the object crossed the sky is very typical of a high flying jet."

"The combination of upper atmosphere conditions which produced contrails which rapidly evaporated, along with a low angle of the Sun and the smoke in the air from the fire which got out of control, lit the contrail brightly and reddened it significantly."

Mysterious booms rock Cape Fear region 

Star-News
Fri, 08 Feb 2008 00:00 EST

Loud booms rocked Brunswick, New Hanover and Pender counties starting about 6:40 p.m. today.

Callers from Oak Island, Leland and Supply told the Star-News they heard the booms and felt strong vibrations. One man said he thought his beach-front home was collapsing. Another said it shook her whole house.

A meteorologist at the National Weather Service office in Wilmington said reports of the booms or vibrations were widespread, coming from Rocky Point in Pender County to Leland in Brunswick County.

The Brunswick County 911 center's switchboard lit up with calls from people reporting explosions or loud booms.

A dispatcher said the center had not confirmed the source of the loud noises.

Although a dispatcher at the New Hanover County 911 center said the center had received no such calls, a Star-News staffer who lives in the Sunset Park neighborhood of Wilmington said he heard the noise at his home.

Mysterious booms known as "Seneca Guns" have been reported in the region for centuries. The name comes from a similar phenomenon in New York and Connecticut.

Legend has it that the Seneca Indians are getting their revenge with the guns that Europeans used to displace them.

More scientific explanations say the boom of the guns comes from earthquakes, material falling off the continental shelf, or pockets of hot air exploding like balloons.

"We have no idea what it was," said Michael Ross, the meteorologist at the weather service in Wilmington. "We felt the building kind of shake for just a split second."

Ross said staff at the NWS office was keeping tabs on the National Earthquake Center to see if there was a report of an earthquake in the region, but none was reported.

Ross said he wasn't aware of any military maneuvers off the coast, which occasionally is spotted on NWS radar when aircraft drop material to confuse enemy radar systems.

Calls to the public information office at Cherry Point Marine Corps Air Station in Havelock were not answered.

Check back here for updates on this developing story.

Cosmic Winter - A Lecture by Victor Clube 

Victor Clube
kronia.com
Sun, 10 Feb 2008 16:21 EST

Moderator: In introduction, I just should say that Victor is the author of two extremely intriguing books. The first is The Cosmic Serpent which was published in 1982, and the second is The Cosmic Winter, published in 1990 in collaboration with astronomer Bill Napier. And I think that today Victor is going to present a talk illustrated by slides which will continue along the lines that he developed in The Cosmic Winter, which is a book that I urge all of you to read if you can.

Victor Clube.
What I propose to do this morning is kind of take advantage of the few things I talked about last night, and go on from there. But there was a slight hitch with the overlay, which got chopped in half, and I thought as a result of some of the comments that were made I would kick off with a few slides, straight away this morning to, perhaps, just give you a little more of a feel for the things that I'm talking about.

I actually take a little time to gravitate in the community that I'm not familiar with, and I do realize that the need to talk of catastrophism in terms of planets kind of takes you away from the starting point which I perceive to be more important; namely, the smaller bodies, the meteors, the meteoroids, which I talk about. And I thought, perhaps, therefore, a few illustrations might just put you in a slightly better frame of mind for receiving what I'm talking about. So if I may have the slides, please. Indeed, I can't really claim much for any of these pictures, but this is an illustration of the zodiacal cloud.

This is the disk of dust in the inner solar system which, if you're in a good observing site you may be fortunate enough to see. I come from England. We never see it, so it's rather a dramatic thing to show a picture where you actually can see this cloud projecting away from the Sun, below the horizon, into the plane of the ecliptic.

That dust is cometary and partially asteroidal material. It is a decay product built up by comets over longish periods of time in the inner solar system. Next slide please.

This is familiar to you all. This is just a meteor shower. The objects producing these meteors are typically a gram or so, maybe a tenth of a gram, maybe ten grams. These are breaking up, or burning up, at high altitude in the atmosphere 100 kilometers, and they are not dangerous.

That picture I showed you a bit of yesterday, and this is really just the painting illustrating that some people, in the past at least, perceived something looking like meteors as being capable of causing damage; indeed sufficient damage to be described as "the end of the world." And to some extent part of our problem in modern science is whether we should believe this kind of version of history.

We do know that large meteoroids, ones as large as 10E11, 10E12 grams, or larger - that's the mass of the Tunguska object - so anything which I would call Tunguska or super Tunguska is capable of producing this kind of damage. It's usually things that explode above the level of the ground, maybe five or six kilometers in the air. They are smaller than comets. And on the whole, we can't see any of them. They're out there. There are telescopes now detecting such sized objects, but really it's not an active, ongoing business.

Much of my talk is actually about meteoroids between Tunguskas and meteors. And they're objects with masses of the order 10E6, 10E8, 10E10 grams. These are the objects which produce what I call fireballs in the atmosphere, and I showed you that the Chinese were recording these large meteoroids, fireballs, down the centuries, and it was they that dramatically changed in numbers as the years went by. You must not get the impression that we in Europe were unaware of fireballs.

The fact is, we just didn't have an organized observatory, anywhere, doing the job, so we weren't really quite as an advanced civilization as the Chinese. Nevertheless, people in the seventeenth/sixteenth century were trying to come to terms with the phenomenon they obviously observed. And this is merely a theoretical picture, if you like, illustrating what a fireball was.

Here are the frightened folks down below. There are the fireballs coming down. And there is the source - some kind of clash in the sky; slightly more modern than gods fighting each other, armies shooting each other and the fireballs a stray shot, if you like. Well, some theory, but at least somebody is clearly thinking about it.

This is back to front, but it doesn't matter, it'll serve. This is actually a satellite. I forget its name (Geos II, or something like that), which was measuring dust particles out of the atmosphere above the Earth, well into space, and some twenty/thirty years ago. And it was one of the experiments that began to give us a little more insight into what was around out there. None of this we could see.

This satellite was fitted with dust fences and it went up to check if the zodiacal cloud was there, as we saw it. And the interesting thing was that the prediction, from what we observed, roughly turned out to be right. And it's that heap of particles of a certain size, up to about a hundred microns. We're looking at the larger particles on the right. And that sort of normal shape and histogram is, in fact, the expected zodiacal cloud particles which this satellite was meant to measure.

The surprise in the experiment was that there were a lot more dust particles, of smaller size, in fact occurring with time intervals between them which were very small. And the number of dust particles which you see there is actually comparable in size to the number in the zodiacal cloud. These dust particles could only be understood as being the fragmentation products of larger objects, the debris of which the satellite was passing through.

What we discovered, in fact, from this experiment was that meteoroids, the objects that produce fireballs, were also breaking up at a very high level above the Earth. And there were objects of masses like 102 through to a million grams. They would, if they could hold together, produce fireballs at a low level.

But, because they are so weakly constituted they break up at very high level and produce, really, micron/submicron dust that then floats down through the atmosphere, undetected. So the message I want to give you is that it's not all zodiacal dust that's making up the material that arrives in the atmosphere. It's actually breaking up from meteoroids.

Much of my talk this morning will relate to what I mentioned yesterday-a thing called the Taurid meteor stream, and, again, I want you to know that the Taurid meteoroid stream is not something that we, as it were, learned about fifty or sixty years ago from meteors and we've simply been checking that result ever since.

The remarkable thing about the space age is that it has actually revealed more and more things in the Taurid meteor stream which is actually built up from interpretations of all these modern observations that were simply not available at the time, for example, when Velikovsky was writing Worlds in Collision.

So, essentially, what I'm describing to you is a scientific story based upon the very latest evidence from space. And this is merely illustrating one example of the kind of surprises that came our way.

The Apollo astronauts planted seismometers on the Moon, primarily to measure Moonquakes. But they got diverted from their business by the discovery that objects, which they didn't expect at least, were hitting the Moon. These seismometers regularly recorded large bodies hitting the Moon like the meteoroids which I've just been describing. And this diagram is an illustration of the record of the incidence of these meteoroids, integrated over a period of about seven years until NASA switched the machine off- in exasperation, apparently, because they didn't think it was telling us anything very interesting.

Nevertheless, for seven or eight years they accumulated this data, and what you see here is the integral result of the observations, per day, through the years, throughout the whole of this seven or eight year period. And, of course, it looks a little like the skyline of Oxford, where I come from, but never mind, the prominent thing is that you see one remarkable peak in the middle which is, in fact, centered on about the 30th June. And all that peak, in fact, coincides with the products of one year's observing. So in that one year, 1975, in fact, we had a flood of objects hitting the Moon, which actually were also hitting the Earth, and they all were present, apparently, in the same stream, as was responsible for the Tunguska object in 1908 which, as you recall, also arrived the end of June. In fact, this end of June is an interesting time. It's the time when we pass through the Taurid stream, going in one direction. And the other direction is, in fact, the beginning of November, and you can see some signs of that in this same diagram.

This observation was a unique observation of a great swarm of fireballs, or meteoroids, that nobody had ever observed before and has never observed, properly, since. And yet it's there. And interestingly enough, though I just said we've never seen it, there are signs of it in the meteor observations if you start scouring through them, and with care. We know that there is a huge swarm of this material in the Taurid stream, which is moving around in what is called the "mean motion resonance." That is, Jupiter strongly influences it's orbit, and there is every reason to believe that because all this material is in this huge resonance, there is some huge source that has been feeding these meteoroids into it, down through the millennia.

That you could not have known before 1975. But, in fact, the results have gradually become clearer and clearer to us in the last twenty years. This is just to remind you of a picture you have seen already, I'm sure, of the Tunguska event, the sort of thing it does. It is a dramatic type of explosion. It doesn't extinguish dinosaurs because it's localized. But it's easy enough to picture an object which is, let's say, two or three hundred meters in size rather than the fifty to one hundred meters which we believe the Tunguska was, and recognize that it will obliterate a very, very broad area indeed. In fact, its' effects would be quite dramatic and certainly might wipe out a small nation, and seriously perturb a civilization.

What you're looking at here is an illustration of the orbit of the Earth around the Sun, but I'm superimposing on it some orbits of some objects in the Taurid meteor stream, just to give you a feel for what's going on. There is the stream. It's an elliptical stream. The period is typically about three and one third years. It includes the well-known comet, comet Encke. And Jupiter, which doesn't appear on the diagram is just off.

The orbit, if you like, embraces the picture. The Taurid stream then reaches out to almost as far as Jupiter. And so we have a bulk of material circulating in this very, very broad stream. It takes a couple of months, at both intersections with the Earth's orbit, for us to cross. And there it is at the top at the beginning of November, and coming away from the sun at the bottom at the end of June.

If I might just put the picture of the fireballs back on which you were looking at yesterday, we'll try and get it all onto the screen, and I'm going to leave it up because I want it to get embedded into your gray cells as one of the more revealing diagrams, as to what is going on in the inner solar system. All you really ought to look at is the top right hand diagram. The bottom right hand one is just an improvement of it. It shows the sudden surges in the fireball flux, which lasts for something like fifty years, which I was describing to you yesterday. Now these surges have correlated with them an increase in the flux of Tunguska sized objects. So where the normal flux of Tunguskas, which is related to the background or subordinate level in that plot, is something like one every century or so, the rate goes up to like one a year or so for these periods of time. And there's nothing wrong with the sense that the world is in some kind of danger, under those circumstances, in order to over-exaggerate it because any one country, no doubt, would escape. In fact, many countries would escape.

The danger, nevertheless, is unpredictable and given the fact that we now live in a global village there's no question we would all be aware of this kind of event in our locality, as people indeed were in the past, and they feared it.

The interesting thing is to look at the left hand diagram, which is a plot of the same fireballs, per month, per century. And the important point to note is that it's not uniform across the board. When you get the peaks you see it concentrating in mid summer and early November. The actual peaks are related to enhancements of the hub of the meteoroids in the stream that I've been talking about, the Taurid stream.

And the broad picture is that in spite of your preconceptions in this business there are Shoemaker-Levy type events occurring which influence, or affect, the Earth. And the debris, instead of all piling into the planet in one go, in this instance, runs around the orbit for several circulations-maybe a dozen or so-and the planet is at risk, as it were, again, and again, and again. And with that kind of situation you do get conscious of your environment and some of the possible dangers that it might carry.

I'm gong to follow my script a little at this point, if you don't mind, and because I tend to meander when I talk and I want to try and fit as much as I possibly can into the available time.

I want to summarize the meaning of this diagram, which I'm going to ask you to gaze at, endlessly. Chinese fireball observations indicate that there is a great swathe of disintegrating dark debris circulating in the inner solar system, occasionally producing Tunguska and super-Tunguska bombardments.

This is a picture that is unlike the one that you believe you know has been going on for the last two millennia, which are within recorded historical time rather than, let's say, mythological and protohistorical time. It's meant to be the bit of history we understand.

This swathe cuts across the Earth's orbit around mid-summer and Halloween, in a huge elliptical torus, reaching out short of Jupiter, as I have described. And its further disintegration is responsible for the system we know of as sporadic meteors, which all lie close to the ecliptic and the zodiacal dust, as I've described.

It is hardly possible to understand all this material steadily disintegrating into dust except in terms of a once very massive comet at the heart of the Taurid electrical torus, with an orbital period of about three and a third years. Indeed, if this torus were now visible you would see it like a huge additional Milky Way in the sky, slightly inclined to the ecliptic and for all the world in a configuration like one that was described in Plato's Timaeus , in his account of God's construction of heaven and Earth. I don't know how many of you recall or are familiar with this, but what he does describe is Earth and heaven being made in the form of a circular belt which is cut into two strips, and God then places one strip in slight inclination to the other. And the theorists then get in a bit of a 'tizz trying to explain this as an earlier account of the ecliptic and the equator.

In fact, the account makes it very clear that we're talking about material things in both cases, and in fact is more plausibly-much more plausibly- related to the Taurid stream in a more visible state, as it would have been in two or three thousand, and more, years ago. Heaven would be the home of the gods-being the Taurid torus-while Earth would be the home of the planets, being the plane of the ecliptic.

People in the past, of course, have suspected these slight shifts of name for the ecliptic and an individual planet. In fact, we can see some reason behind other descriptions that are on offer to us, where we have some part of the cosmos described as a glowing cavern carved out of the cosmos.

Early pictures seem to describe heaven in this way and it may well, again, be that they were describing early sightings, if you like, of this Taurid stream. I do want to get the message to you that in spite of your being unfamiliar with it, and in spite of it being so difficult to see, it is a very massive system. It does correspond to the material of a comet, a hundred kilometers or more in size-far, far larger than anything that we are normally familiar with but, of course, we do see these things further out in the solar system.

This kind of picture, my colleague, Bill Napier, and I, were describing in the book that Irving kindly mentioned, The Cosmic Serpent, twelve years or so ago, and that was a time when we were actually predicting that this stream would have asteroids in it. Of course, that was not known at that time; they had not been observed. But we now live in a time when many asteroids have now been discovered in the stream. So the kind of logic that led to this picture has really been firmed up considerably by the fact that we now see the very things that we thought must be there.

So, it is now the home of about a hundred Earth-crossing asteroids, not all of which, of course, we have yet seen, and these are just part of the dark but disintegrating debris. It's not too much to suppose these were all once dying cometary gods. Within the stream is one known comet-comet Encke, which I've mentioned, and this is getting steadily fainter. And if you wanted to transfer this two or three thousand years ago, you might like to think of this as a dying cometary god.

I'd like to remind you now that one of these peaks that you are looking at here-the 1601 occurs round about 1640 through 1680, and it coincides with the end of the Thirty Years War in Europe, and the Civil War in England. I mentioned this briefly last night. Cromwell, and others of that time-I only name him because, of course, he's a familiar name to you, but there are many others-described all the upheaval of the time, in millennarian terms, as due to "God's revolution" only a century after Copernicus' De Revolutionibus.

My point here is that the word "revolution" is popularly used nowadays in a social sense. It didn't have that at the time Copernicus was writing; it acquired it. It acquired it at the time of the English Civil War. And it was because of the perception that things in the sky were driving things, terrible things, that were happening on the ground. Only three hundred and fifty years ago, then, mankind was still in the era of an invisible sky god from a once visible heaven associated with angels, fallen angels, and dangerous demons hurling thunderbolts.

We have to get rid of the idea that our ancestors thought that space was empty. They didn't have [the] specialized astrophysical knowledge that has allowed me to build the Taurid stream for you; they just knew it was there. That's really rather a remarkable thing. We've had to unlearn that knowledge in the last three hundred and fifty years in order to put ourselves in the state of rediscovering it.

So, what was The Enlightenment only forty years after Cromwell? It was the pragmatic English decision to get rid of all the angels and demons, invisible sky gods, and a once visible heaven. It was the decision to stop worrying about the evidence of fireballs and the supposed behavior of comets. It was a decision to reconstruct the cosmos without heaven in the solar system and put it in the ether or outside the cosmos altogether of infinity al la Bruno. It was the decision to create a purified, less frightening cosmos in much the same way as Aristotle did after Plato. On both occasions we shifted from astrology to physics, and from a sky of foreboding to a sky of inspiration, from prison and terror to freedom and hope.

Indeed, the cry of the revolutionary periods of 1640 to 1680 and 1760 to 1800, the time of the American War of Independence, was the cry of freedom from heavenly oppression, demons, and fireballs.

For the last two hundred years of Enlightenment we have been rewriting history so that the cry of freedom is from earthly oppressors. No wonder the world has gone wrong and the astrophysicists today cannot come to terms with the Taurid torus. I'm really trying to say that this is just not an astrophysical discovery that we are talking about. Everything has got to, sort of, turn around in order to come to terms with what is being said. And this, in a way, is rather like what Irving was describing beforehand. There is a paradigm shift involved in recognizing that it's not just ancient history we have got wrong-it's all history.

So, what is my point? My point is that you do not have to dabble first in mythology and prehistory and geology, as Velikovsky did, in order to understand the sky. You first take the modern sky accessible to science, especially during the Space Age, and you look at its' darker debris with a view to relating its behavior to the more accessible human history which we can, in principle, really understand. And by this approach you discover from the dynamics of the material in space which I'm talking about that a huge comet must have settled in a Taurid orbit some 20,000 years ago, whose dense meteor stream for 10,000 years almost certainly produced the last Ice Age.

(Missing Text due to change of tape)

The chance of a collision with Kronos, as with any other comet was, in fact, remote. And mankind settled into a Golden Age. But some time at perihelion, around 3,000 B.C., it is likely that Kronos ran very close to Venus and split, like Shoemaker-Levy. And a trail of new, dazzling comets circulated around the Taurid stream-evidently, for centuries. Somewhere in this array still was the Kronos remnant; less bright, perhaps. And a new leader, Zeus or Marduk, perhaps, much brighter, together with a new serpentine Milky Way, the home of chaos.

By 2,000 B.C., due to an orbital precession, things got worse, for the trail was now crossing the Earth's orbit and mayhem ensued. The Sumerian civilization came to an end under a barrage of Tunguskas, thunderbolts, all over a period of a couple of centuries and we were now in a sky of foreboding. Then passed another 2,500 years with Zeus in decline and Kronos already barely visible, while the latter's orbit precessed until we come to the next intersection with the Earth's orbit around 500 A.D. when mayhem again ensured. This time the Roman civilization collapsed and the dark age was in place. And it was Plato and the Christians, of course, with their knowledge acquired from the Magi who had predicted this "end of the world."

In the medieval society which then emerged, it was natural that they should first invoke the world of demons and foreboding. But eventually it seemed that the danger was passed, and by the twelfth century the Europeans were changing back to the Aristotelian picture of inspiration and supposed enlightenment. The Taurid and probably the Kronos remnant, are still there, of course.

And the next crossing of the Earth's orbit will be around 3,000 A.D. There's no guarantee of avoiding additional bombardments before then, and, of course, there may be another Jesus Christ.

I'm going to come to an end and possibly leave no time for questions, I'm afraid. But I am told that I'm going to be up here again.

What, then, should Velikovskian's make of all these additions to our cosmic environment? Well, my first point, I think, is that we do not need to move the planets around to get catastrophes. Super Tunguskas will do it all.

Point two-everything we say makes no challenge to conventional physics, or astrophysics, for that matter.

And point three-everything we say, as Velikovsky would have wished, does make a challenge to conventional history.

The new picture is one of punctuated peace. It is the picture, I would suggest, enunciated by both Spengler and Toynbee (not the world's most favorite historians nowadays), one in which new cultures emerged from chaos, with a shout, to become civilizations which then stagnate or decline, slowly. Only with a fresh cosmic crisis do they climb to new heights or collapse altogether, providing us with a new paradigm shift.

The picture I am describing is, again, rather like the one that Irving Wolfe was describing previously. I would like to follow Irving Wolfe here, and suggest that we are, indeed, approaching the position now when we can reconstruct catastrophic history and demonstrate it as evidence for the controlling influence of one giant comet over the last 20,000 years of evolution.

There is nothing very arbitrary about introducing giant comets to do all this. The fact is, that we see them around. The idea that giant comets dominate evolution is very much in keeping now with the discovery, further out in the solar system, of objects like Chiron which are known to come into the inner solar system. The dynamics do it. They are bound, some of them, to settle in the way this other object that I have been talking about, has been.

These objects are also found among the long period comets from the Oort Cloud, and astronomers are perfectly capable of constructing perfectly respectable physical pictures of how these giant comets are transferred from the remote Oort Cloud down into the central solar system, almost as a matter of regularity. Thus, we argue that the perturbation of the Oort Cloud determined the long-term arrival rate of giant comets attacking the Earth. If so, due to the Sun's motion up and down in the galactic plane, we can predict the periodicity in terrestrial evolution.

This periodicity is certainly now observed and correlates exceedingly well with the Sun's present position in the galactic plane, and with its motion up and down in the galactic disk. All of these things are kind of rather well known and understood by astrophysicists. The period also fits the dark matter which we now believe to be in the galactic plane and which we infer from other kinds of observations altogether.

In fact, too much is now hanging together in this wide range of information that I am giving you, to really doubt that it's got the bare bones essentially there. And we may now be in a very interesting position of being able to say something about the dark matter itself. It could, indeed, be cometary material of some kind, and it could be the very material that makes the stars that we see being made in the spiral arms in the galactic plane. What I'm trying to say is that through grasping at some of these complexities associated with our history-and we have learned more about comets than we would otherwise have done from pure physics alone, carried out, if you like, in its very pure laboratory. The historical findings, I would maintain, and I'm sure Velikovsky would argue in a very similar way from his picture (not perfectly correct as it was) ...

The historical findings, in other words, are highly relevant to astrophysics. They're a sort of way of integrating all this knowledge. It has a completeness which a former picture did not have.

Thank you.

(Question and answer period follows)

Questioner 1: Victor, I see some irony in the statement that we don't have to move around the ... I don't know, maybe we don't have to, but I just want to remind you that you have ... of course.

But two issues of Scientific American ago, mainstream astrophysicists ... the idea that the Moon was created out of a clash of the Earth and Mars, so we have here, somehow, intriguingly, a movement out of mainstream ... scholars to planets being moved around, and even clashed, to create the Moon. And then we have more or less a near-catastrophist approach which is rather not cautious to make ... it's just a statement, not a question.

Clube: Right. No comment then.

Moderator: That's the Oxford debating experience!

Questioner 2: (question not asked from microphone) ... kind of an intellectual construct in bringing echo(sp)-physical evidence that a field of cometary material was ... out beyond our solar system, as the source of comets?

Clube: Well, I know the comet. I don't really believe it at all. We do see the Oort Cloud. What we observe are the comets from the Oort Cloud. And it's understanding how these comets could come to us to be seen that leads us to build sensible models of the Oort Cloud. OK, it's a construct.

But then, perhaps, so too, is a hydrogen atom. It's one of the more plausible constructs of astrophysics, if I could put it that way. It is much more solid than many of the things we heard criticized a little while ago in the cosmos at large. It's a fact!

Van Flandern: On that part not all astronomers agree that the Oort Cloud is a plausible construct. But my question for you is- you argued that at the end of 500 AD there probably was some involvement with the Taurid stream and the decline of the Roman Empire. Now, inside recorded history we have details of how the Empire came to an end, but I don't recall any details ... that influence that.

Clube: That is correct and it's certainly worthy of a lecture in its own right. I have written a little on this, and I think the thing that one has to address is that it is well known that this was a period, first of all, when people thought the end of the world was coming. OK? And I pointed, already, to you the evidence that there were fireball flux, which is free for interpretation and would guide you to this view.

Now, one of the problems with the management of the Roman Empire was the fact of what is called "deserted lands." Great tracts of land were apparently deserted and people were on the move. It was a period of migrations, as you know. And it was the management of this that was, clearly, a severe problem- increasingly a severe problem for the Roman Empire from round about 200 AD onwards.

And one can formulate, I would submit, an interpretation of all that was going on in terms of this problem getting more and more acute until you come to the time of the initial Dark Age in Britain, by which time chaos was almost intervening. We have very good records, in Britain, at least, of survival really going back to subsistence level for two generations. And some very interesting evidence from famous author Gildas, who described the fire of righteous vengeance which came down and caused a great catastrophe in England in 441 AD.

Now, what I'm really getting at here is that everybody knows about this catastrophe. There are endless attempts to explain it. None of them are normally in terms of the obvious-the one that described the astronomical event.

What I am trying to say is that there is evidence for Tunguska events throughout that period. It's simply put aside as not relevant because the historians are guided by astronomers who would never think of such a thing.

Giant Crater Found: Tied to Worst Mass Extinction Ever 

Robert Roy Britt
SPACE.com
Fri, 02 Jun 2006 12:00 EDT

An apparent crater as big as Ohio has been found in Antarctica. Scientists think it was carved by a space rock that caused the greatest mass extinction on Earth, 250 million years ago.

The crater, buried beneath a half-mile of ice and discovered by some serious airborne and satellite sleuthing, is more than twice as big as the one involved in the demise of the dinosaurs.

©Ohio State University

Gravity fluctuations beneath East Antarctica measured by GRACE satellite. Denser regions appear more red; the location of the Wilkes Land crater is circled (above center).

The crater's location, in the Wilkes Land region of East Antarctica, south of Australia, suggests it might have instigated the breakup of the so-called Gondwana supercontinent, which pushed Australia northward, the researchers said.

"This Wilkes Land impact is much bigger than the impact that killed the dinosaurs, and probably would have caused catastrophic damage at the time," said Ralph von Frese, a professor of geological sciences at Ohio State University.

How they found it

The crater is about 300 miles wide. It was found by looking at differences in density that show up in gravity measurements taken with NASA's GRACE satellites. Researchers spotted a mass concentration, which they call a mascon-dense stuff that welled up from the mantle, likely in an impact.

"If I saw this same mascon signal on the Moon, I'd expect to see a crater around it," Frese said. (The Moon, with no atmosphere, retains a record of ancient impacts in the visible craters there.)

So Frese and colleagues overlaid data from airborne radar images that showed a 300-mile wide sub-surface, circular ridge. The mascon fit neatly inside the circle.

"And when we looked at the ice-probing airborne radar, there it was," he said today.

©Ohio State University

Airborne radar image of land elevation in East Antarctica. Higher elevations appear red, purple, and white; the location of the Wilkes Land crater is circled (above center). Image courtesy of Ohio State University . An inset of the Chicxulub crater is included for comparison.

Smoking gun?

The Permian-Triassic extinction, as it is known, wiped out most life on land and in the oceans. Researchers have long suspected a space rock might have been involved. Some scientists have blamed volcanic activity or other culprits.

The die-off set up conditions that eventually allowed dinosaurs to rule the planet.

The newfound crater is more than twice the size of the Chicxulub crater in the Yucatan peninsula, which marks the impact that may have ultimately killed the dinosaurs 65 million years ago. The Chicxulub space rock is thought to have been 6 miles wide, while the Wilkes Land meteor could have been up to 30 miles wide, the researchers said.

Confirmation needed

Postdoctoral researcher Laramie Potts assisted in the discovery.

The work was financed by NASA and the National Science Foundation. The discovery, announced today, was initially presented in a poster paper at the recent American Geophysical Union Joint Assembly meeting in Baltimore.

The researchers say further work is needed to confirm the finding. One way to do that would be to go there and collect rock from the crater to see if its structure matches what would be expected from such a colossal impact.

Today in Cape history: Third comet visible in 12 years

Jack Coleman
Cape Cod Today
Mon, 04 Feb 2008 18:46 EST

©Unknown

On this day in 1664, as described in the book "Cape Cod Historical Almanac" by Donald G. Trayser, "the people of Cape Cod and other parts of New England saw the last of a great comet which excited fear and awe. It appeared November 8th last, and continued to this date, the third comet witnessed by early settlers in the space of 12 years.

"The first appeared in December, 1652, the second in February and March, 1661, and the third as noted above," Trayser wrote. "Comets were fearsome things to people in these days."

Trayser quotes Nathaniel Morton, secretary of Plimoth Colony, who wrote of the comet of 1663-64 that " ... it was no fiery meteor caused by exhalation, but it appeared to be sent immediately by God to awake the secure world."

"Night after night, 'the great blazing starre' was observed in the southern sky," Trayer wrote, "and for several years after it, all the calamities and evil things which occurred in the world were ascribed to it."

The period engraving shows two of the comets from the era (illustration credit).

Comets in History: The Journal of Hamel and Korea

Hendrick Hamel
The Journal of Hendrick Hamel
Mon, 11 Feb 2008 18:51 EST

At the end of the year [1664] we saw shortly after each other two tail-stars or comets arising in the sky. The first one, in the southeast, was to be seen for almost two months. After that another one appeared in the southeast. The appearance of these celestial bodies, caused a big panic in the country. The war-fleet was standing by, the guards of the ports were reinforced, all fortresses were provided with extra provisions and extra munitions, while cavalry and infantry were exercising daily. Also was it not allowed to light any lamps, especially not in the cities along the coast. This fear was caused by the fact that when the Tartarians invaded the country, there were also similar signs in the firmament, as well as at the beginning of the war with the Japanese.

Many a Korean asked us what we thought of it and if we considered the appearing of these celestials also as a bad omen. We answered that we, in Holland, usually expected that the appearance of a similar sign was an omen of one or the other disaster, be it a war, flooding or an epidemic.

Hendrick Hamel was the Dutch "Marco Polo", exploring Korea in the middle of the seventeeth century.

Dr. Stan's Plan to Save Earth From Asteroid 

ABC News
Mon, 11 Feb 2008 15:11 EST

'Let's Blow It Up!' Not the Answer, Says Astronaut Preparing for Spacewalk

©Stan Honda/ AFP/ Getty Images

Space shuttle Atlantis mission specialist Stanley Love on Feb. 4, 2008 at Kennedy Space Center in Cape Canaveral, Fla. Love is preparing to make a spacewalk to attach the European Space Agency's Columbus laboratory to the International Space Station.

Astronaut Stanley Love will be walking in space today to help attach yet another new section of the International Space Station, but he has even bigger plans in mind. He'd like to save the world.

Love, who is aboard the space shuttle Atlantis, has hatched a a plan with his colleague Ed Lu to prevent Earth from getting hit by an asteroid.

"Many methods that people have talked about involve things like nuclear weapons - let's blow it up! Or smash something into [an asteroid] at eight kilometers per second and blow it apart," Love said. "Those methods are a great way of getting kinetic energy into the target, but you are not quite sure what you are going to get after that. Instead of one big rock, you might have a swarm of smaller rocks."

Love's and Lu's plan would send a spacecraft into orbit around any asteroid with Earth in its sights.

"You sidle up next to it, and you just hover there for like a year. Now you need a good long warning time on the asteroid because during your year of hovering, because of the very tiny gravitational pull between the spacecraft and the asteroid, that amount of pull is about the same amount of thrust as gluing a housefly beating its wings, to an asteroid," Love said. "A tiny amount of thrust, but build up over a year, then given 20 years to drift, in that direction, you can turn an asteroid strike into a miss."

Before he saves Earth from an asteroid strike, Love has to help out with a spacewalk. The astronomer-turned-astronaut was scheduled for one spacewalk during STS 122, the current shuttle mission, but because of the unexpected and unexplained illness of his colleague, Hans Schlegel, he will go out into space twice.

Love and astronaut Rex Walheim will prepare the $2 billion European Columbus module for installation on the International Space Station.

It's no big deal, he told ABC News, in an interview before his launch.

"Mainly it is an attitude of mental flexibility. Don't be married to the plan," he said. "You know that at any moment the plan may change and the finely crafted choreography you worked out may not work out that day and you may have to do something else."

Love is enthusiastic about his mission.

"I am very psyched in a wow gee whiz way. It is hard to explain. I think enthusiasm and professionalism go hand-in-hand," he said. "You are not going to be a very good professional if you don't enjoy what you doing. But pure enthusiasm without professionalism is dangerous."

He certainly plans to stop once in awhile when he is on the spacewalk and look around.

"There will be times when I need to hang tight, when I don't have something specific that I have to do and those are the moments that everyone has advised me, take those moments and look around, savor the moment - be where you are and appreciate it," he said.

What makes this space shuttle mission to the International Space Station important? Love says it means the space station will truly be international now.

"This European community has invested their resources, their people, and their enthusiasm in building this Columbus module that we are adding to the space station," Love said. "Right now we have physical parts of the space station from the United States, from Canada and from Russia and now we are adding in another partner and that partner itself is composed of the many member nations of ESA."

The newest partner is the 11-nation consortium of the European Space Agency.

What would he like to do next? Love wouldn't mind going to the moon. While it may be a forbidding place, so is, he says, Antarctica.

"I imagine the first people to go to Antarctica found nothing there but ice and wind and cold, now of course Antarctica is like the premier science lab for the Earth and glaciology and geology and atmosphere sciences. All this great stuff [is] going on there in this place where it was worth your life just to look at 100 years ago," he said. "So I think maybe the moon will be like that in 100 years - an amazing science lab where people go to find out stuff about our world and our universe".

As an astronomer he is really hoping for a chance to see the stars from a different angle.

"I expect the light pollution on the space station is as bad as it is in Houston. I am not sure how good a view I am going to get," he said. "I have had people come back and say if you get a chance, in the shuttle cockpit, turn off all the lights during a night pass when nobody is working and look out the window. It is really cool."

Flashback: Debating the Dinosaur Extinction 

by Leslie Mullen
Astrobiology - NASA
Wed, 13 Oct 2004 18:04 EDT

The dinosaurs dominated the landscape for 160 million years, living over a thousand times longer than modern humans (Homo sapiens first evolved about 150 thousand years ago). During this vast stretch of time some dinosaur species became extinct, but overall the impression is one of an immensely tough class of animals that could endure whatever hardships the planet managed to throw at it. When the end finally came, it came from beyond Earth.

A meteorite impact 65 million years ago is the simple explanation for the extinction of the dinosaurs. The exact details are much more complex, and researchers are still trying to nail down exactly what happened. The Cretaceous-Tertiary (K-T) extinction event is like an ancient tapestry that has become matted and soiled due to time and neglect. There are hundreds of threads of evidence that need to be untangled, smoothed out, and put in their proper place before a clear picture can emerge.

The first, most important thread of evidence is a strip of clay that runs through rocks around the world. Known as the K-T boundary layer, this is the line no dinosaur could cross (although their relatives, the birds, did survive).

In 1980, a team of researchers led by Luis Alvarez and his son, Walter, discovered that the boundary layer contains a relatively high concentration of iridium. Iridium is rare on the Earth's surface but is often found in meteorites. During the molten phase of our planet's formation, most of the iridium of Earth traveled down with iron to form the planetary core. The Earth does receive a light surface dusting of iridium from the occasional meteorites, and some volcanoes can release iridium if their lava comes from a deep enough source. These events give the planet's surface a background iridium level of 0.02 parts per billion (ppb) or less.

Depending on the location of the rocks, the K-T boundary layer has varying amounts of iridium, but all are far above that background level. The section analyzed by Alvarez had 9 ppb. Other sections have upwards of a million times the background level. Luis and Walter Alvarez surmised that a large meteorite rich in iridium must have hit the Earth, and the after-effects of the impact led to the demise of the dinosaurs.

Later, a large impact crater underneath Mexico's Yucatan peninsula was fingered as the smoking gun. When a meteorite punches the Earth's crust, some rocks and minerals are vaporized, some are flash heated and become molten, while others shatter, or become "shocked" in a distinctive pattern. Samples of the Chicxulub crater had all these features of a meteorite impact. The crater was dated to be about 65 million years old, the same age as the K-T extinction.

The meteorite that made the Chicxulub crater was 10 to 15 kilometers in diameter, or about the size of the island of Manhattan. It screamed to Earth faster than a bullet, smashing open a vast cavern 40 kilometers deep and 100 kilometers across. This crater quickly collapsed under the force of gravity, leaving a hole 180 kilometers wide and only 2 kilometers deep.

The energy released by this impact was equal to 100 million megatons of TNT. In comparison, the 1980 eruption of Mount Saint Helens released energy equivalent to just 10 megatons of TNT. The atomic bomb that exploded over Hiroshima released energy equivalent to about 10 kilotons of TNT (or 0.01 megatons).

The impact obviously destroyed life in the immediate area, and the shock wave likely generated huge tsunamis and earthquakes further away from ground zero. Other, longer-lasting effects, such as dust and chemicals from the vaporized rocks, dispersed around the world.

The debate about the K-T extinction was contentious before Alvarez's hypothesis, and the discovery of Chicxulub seems to have done little to stem the often emotional arguments about the extinction event.

At first, some doubted that Chicxulub even was an impact crater. The structure is buried 1 to 2 kilometers under ground - half under land and half under the sea floor - and was only discovered by gravitational and magnetic anomalies from readings taken at the Earth's surface. However, samples from drill cores helped confirm that Chicxulub was formed by a meteorite impact.

While most scientists now agree that Chicxulub is an impact crater, not everyone believes it caused the K-T extinction. For instance, some wonder if the Chicxulub impact occurred at the right time. Gerta Keller of Princeton University argues that its true age pre-dates the dinosaur's demise by 300,000 years. However, other scientists contend that Keller's sampling method was flawed, and resulted in an inaccurate date.

Among scientists who agree that Chicxulub was the cause of the extinction, there are disagreements about the tangible effects of the impact. Some scientists think so much dust was sent flying high into the air that the skies darkened for years, halting photosynthesis and killing plants worldwide. Others contend that the dust wouldn't have been so long lasting, since rain would have soon cleared the air. Some have suggested that red-hot impact debris raining back down would have ignited forest fires worldwide, darkening the skies with black soot. Another theory suggests that so much sulfur was sent up into the stratosphere that the rains became like battery acid, poisoning land and sea.

Finally, there are some who believe that while Chicxulub played a role in the extinction, it was not the primary cause. They are seeking answers beyond Chicxulub, wondering if anything else could have contributed to the loss of species. The dinosaurs weren't the only creatures to suffer death and destruction, after all. The K-T mass extinction event killed at least 50 percent of all the world's species. Could a single meteorite impact - even one as large as Chicxulub - have dealt such a fatal blow to life?

More confusion at the k-t boundary 

Science Frontiers
No. 63: May-Jun 1989
Sat, 12 May 1990 18:01 EDT

More confusion at the k-t boundary

Just a few years ago, many scientists, especially physicists and astronomers, considered the Book of Science to be closed in the matter of what happened at the Cretaceous-Tertiary (K-T) boundary, 65 million years ago, and why the dinosaurs met their end. It was declared, rather imperiously, that a large asteroid had impacted the earth, causing much physical and biological devastation. Many scientific papers are still being written on this singular period in the earth's history, and the situation is no longer so clear-cut. We select for brief review four papers, each with a different perspective.

Occurrence of stishovite. Stishovite, a dense phase of silica, is widely accepted as an indicator of terrestrial impact events. It is not found at volcanic sites. Now, J.F. McHone et al report its existence at the K-T boundary, at Raton, New Mexico. (McHone, John F., et al; "Stishovite at the CretaceousTertiary Boundary, Raton, New Mexico," Science, 243:1182, 1989.) A plus for the pro-impact side.

Evidence of a global fire. Soot appears at the K-T boundary at many sites, but where did it come from? Chemical analyses of these soots show an enhanced concentration of polycyclic aromatic hydrocarbons over soots above and below the boundary. This is strong evidence of pyrolytic action at the K-T boundary; i.e., widespread fires. (Venkatesan, M.I., and Dahl, J.; "Organic Geochemical Evidence for Global Fires at the Cretaceous/Tertiary Boun dary," Nature, March 2, 1989.) Fire could have been initiated by either volcanism or impacts.

The evidence of the traps. Traps, like India's famous Deccan Traps, are extensive flood basalts. In this paper, basalt flooding has been correlated with mass extinctions of marine life during the past 250 million years. The Deccan Traps were formed right at the K-T boundary. Traps could, however, be initiated by asteroid impact, which could stimulate eruptions. (Rampino, Michael; "Dinosaurs, Comets and Volcanoes," New Scientist, p. 54, February 18, 1989.)

The dinosaur angle. If dinosaurs were truly susceptible to extinction by either asteroid impact, widespread volcanism, or some combination of both, one would expect to find their numbers and diversity drastically curtailed during Mesozoic impact events. Instead, the dinosaurs not only survived these impacts but prospered. Their demise, which began before the K-T event, was probably not due to either impact or vol canism. (Paul, Gregory S.; "Giant Meteor Impacts and Great Eruptions: Dinosaur Killers?" BioScience, 39:162, 1989.)

Reference. Impact craters and stratigraphic evidence of catastrophism are cataloged in: Carolina Bays, Mima Mounds and Anomalies in Geology, respectively. For information on these catalogs, visit: here.

No fiery extinction for dinosaurs 

By Paul Rincon
BBC
Tue, 12 Feb 2008 17:56 EST

It is unlikely the dinosaurs perished in a global firestorm triggered by the asteroid strike on Earth 65 million years ago, scientists have claimed.

A popular theory suggests the impact, which was centred on Chicxulub in Mexico, generated enough energy to set off a raging worldwide inferno.

But a new study shows rocks laid down at the time contain little charcoal - a possible tell-tale record of fires.

The researchers have published details of their work in the journal Geology.

The wildfires theory had grown up from previous research. One study had even found evidence of soot in rocks from around the Earth dating to the time of the impact.

Sun block

It is thought that in addition to the devastation these fires caused, the soot thrown up into the atmosphere as a result of the cataclysmic event may have helped block sunlight, causing global cooling and a shut-down of photosynthesis.

Plants not consumed in the inferno would have just shrivelled away - so the theory goes.

CHICXULUB IMPACT CRATER
# Approximately 180 km across
# Now buried under one km of carbonate sediments
# Asteroid responsible for Chicxulub was 10 km wide

But now Claire Belcher, of Royal Holloway, University of London in Egham, has come forward with research that challenges this particular view of dinosaur Armageddon.

She studied six sites in a transect through the western interior of North America. Each site dates to the end of the Cretaceous Period when the impact occurred.

Each of these sites records a geological boundary dividing the end of the Cretaceous period from the beginning of the Tertiary.

This Cretaceous-Tertiary boundary, or K-T boundary, marks the extinction of the dinosaurs and is thought to be associated with the impact of a large space object because the sedimentary rocks of this layer contain large quantities of the element iridium, which is most commonly found in meteorites.

Charcoal trace

She and her colleagues looked for traces of charcoal in these rocks, which could only have been produced by burning biomass, such as vegetation. But they found very little charcoal in these layers.

"It's significant because most people model the K-T boundary in terms of the thermal energy released," Belcher told BBC News Online. "It's often said that temperatures on the ground reached 1,000 [Celsius].

"But 40% of species survived the impact. How could a small mammal survive temperatures of 1,000 [Celsius]?"

The researchers conclude that North America, close to the site of the impact, could not have been engulfed by wildfires, as some have suggested.

Belcher and her co-authors acknowledge that rocks from the K-T boundary contain soot, but argue there could be other reasons for it than wildfires.

For instance, the impact could have vaporised hydrocarbons in the rocks at Chicxulub, creating soot. The fireball that rose over the impact site could have expanded through the Earth's atmosphere, spreading soot across the globe.

Soot sweep

Professor Wendy Wolbach of DePaul University, Chicago, US, who linked the soot with wildfires in research published 13 years ago, said she had concerns about the conclusions of the Belcher study.

"I'm not convinced that they can tell the difference between coal and charcoal. The rocks they studied are loaded with coal.

"If there's any difficulty in making that recognition, their conclusions are not sound," said Professor Wolbach.

She added that it was possible Belcher and her colleagues had expertise she did not. But Professor Wolbach pointed out that the team's procedures for identifying charcoal were not made explicit enough in their published scientific paper.

"The new study is very exciting. If correct, it may help narrow the field. But I wouldn't be so quick to exclude the wildfire theory; it still needs to be looked at," said Kevin Pope, chief scientist at Geo Eco Arc Research in Aquasco, US.

"The problem with the wildfire theory is that it is based on computer modelling and theoretical arguments."

Pope said he favoured the theory that the asteroid strike released sulphate aerosols from impacted rocks. In the atmosphere, they would have reacted with water to form sulphuric acid clouds.

These clouds could then have expanded over most of the Earth to block out the Sun, causing global cooling and a shut down of photosynthesis.

Comment: What they didn't consider is multiple smaller impacts as well as a larger one off Yucatan, AND overhead cometary fragment explosions.

Death in June: Lunar Impact and Gervase of Canterbury

by Robert Matthews
Discover
Mon, 01 Jun 1992 17:11 EDT

June is a time for beach parties and barbecues. It is a time for wildflowers and warm breezes and slow summer evenings. It is a time when our sun-orbiting planet cuts across a trail of cosmic debris, scattered by a monster comet, that one fine day may visit a holocaust upon us.

So says astrophysicist Victor Clube of Oxford University. He's been studying the Taurids--a meteor shower that strikes Earth each year in late June and again in November. The Taurids are not nearly as spectacular as, say, the Perseids of August; in June they're not even visible, because they approach from the dayside of the planet. But Clube and his co-workers think the Taurids are underrated. The meteor stream, they say, includes rocks so large--as much as a mile across--that to see one up close would be to lose a city, a continent, or more.

The evidence comes in part from history. In the early morning of June 30, 1908, a huge fireball exploded in the sky above Siberia with the force of a 20-megaton nuclear bomb, leveling 400 square miles of remote forest around the Tunguska River. The glow lit up the sky as far away as Western Europe. The Tunguska object, Clube says, was a 150-foot comet fragment--one of the Taurids.

Another near miss may have happened in 1178. One night in late June, according to a monk named Gervase of Canterbury, eyewitnesses saw a flaming torch on the upper horn of the new moon, which thereupon throbbed like a wounded snake. The throbbing could have been a dust cloud kicked up by a meteorite; a 13-mile-wide and apparently fresh crater named Giordano Bruno seems to be in the same spot as the flaming torch. If so, then the Earth narrowly missed being hit by a meteorite about a mile across--large enough to have devastated a continent.

The moon appears to have been pounded again by the Taurids as recently as 1975, when seismometers left behind by Apollo astronauts picked up the impact of a huge swarm of boulders. The onslaught started on June 22.

Clube and his colleagues believe a single cosmic marauder lies behind all these events. Meteor showers are debris shed by passing comets, and usually the pieces are no more than a few inches across. If Clube is right, however, the Taurid meteor stream includes some large chunks: in addition to the historical impactors, Clube says, there are half a dozen full-size asteroids whose orbits place them squarely in the stream.

Clube and his colleagues argue that the Taurids' range of orbits indicates they were all shed by a huge comet, originally 100 miles across or more, that entered the inner solar system some 20,000 years ago. The comet's orbit took it inside that of Mercury, close to the sun. By 10,000 years ago it was desiccated and brittle, and since then big chunks have been breaking off each time it passes the sun. One of those chunks, Clube thinks, is a comet called Encke. But the core object itself may still be out there. We suspect that the source of the Taurids is in an orbit similar to Encke's, going round the sun every 3.39 years, says Clube. We think we're on the verge of finding it.

Clube believes his killer comet sends bursts of Tunguska-size objects our way every few thousand years or so, and that in the past the dust clouds raised by such impacts have plunged Earth into cosmic winters and perhaps even full-blown ice ages. But he has yet to convince most astronomers that his historical evidence amounts to more than coincidence. It's quite possible some of the June events fit in with a single object, but I think Victor may have turned it into a bit of a conspiracy theory, says Brian Marsden of the Harvard-Smithsonian Center for Astrophysics.

What many astronomers do agree on, though, is that the risk of a large impact, while perhaps not as great as Clube suggests, is worth taking seriously. A committee of NASA experts has recommended that a global network of telescopes be set up to hunt for potential impactors; a second committee is expected to urge NASA to develop a way of nudging an incoming rock out of our way, perhaps with a neutron bomb. After a decade of growing awareness that Earth has been blasted in the past, a consensus seems to be emerging: if we don't want to go the way of the dinosaurs, the danger of an impact--in June or any other month--is one we should not ignore.

Tunguska, the Horns of the Moon and Evolution 

Laura Knight-Jadczyk
sott.net
Sun, 10 Feb 2008 13:39 EST

©Peter Grego

Impression of the 1178 lunar event

Last time I said I was going to talk about how much your "glorious leaders" really hate and despise you and how they are plotting your deaths while most of you are so screwed up that you not only do not see this, you actually dance blithely toward disaster for yourselves and your children. Well, I'm going to get there, but first, I want to tie up a few loose ends and reiterate a couple of points.

As I mentioned in my previous article on this topic, the Discovery Channel special Super Comet - After the Impact, places the comet that wiped out the dinosaurs in a modern setting, using the same type of cometary body assumed to have caused the extinction of the dinosaurs, the same size, same impact location, and utilized all the computer modeling they have done on this past event to try to show what might happen (and to show what they think happened then).

Studies of the history of the Earth via various scientific methods show us that there are relatively long periods of "evolution" punctuated by rapid, overwhelming changes we call catastrophes. Many scientists have noted the periodicity of these punctuational events. What no one seems to know for sure is the mechanism that induces these definitely periodic catastrophes.

It is suggested that the periodicity of these events relates to galactic cycles and there is good evidence for this view presented by Victor Clube in his book The Cosmic Winter. (You can really forget the nonsense going around about "Planet Nibiru" and "Project Camelot"). He suggests that galactic tides induct giant comets into our Solar system and it is their disintegration products which interact strongly and directly with the Earth with variable results at different (and very frequent!) periods which results in the variations in the geological record. Clube demonstrates that the breaking up of a giant comet produces a wide range of debris from objects 10 km across, to hundreds or thousands of 1 km sized bodies, to multiple swarms of sub-kilometer sized bodies. Many of these bodies have sooty, black surfaces making them almost impossible to see and many of them are in an orbit very similar to the Taurid meteor streams, though a few may be in an orbit rotated about 90 degrees. Clube posits that many (if not most or all) of the asteroids in the Solar system split from a giant comet (or many of them) thousands or tens of thousands of years ago, and it is the streams of debris that pose the most serious and immediate threats to our planet.

For example, one of the large asteroids in an Earth-crossing orbit is named Hephaistos. It is about 10 km in diameter, about the same size as the asteroid that is depicted as striking the earth in the above-mentioned movie (the dinosaur extinction model). It is true that the effects of the impact of such a body would be felt globally, but it is not so clear that it would be exactly as "global" as depicted in the movie.

©William Hartmann

A painting showing how the alleged KT Impactor may have appeared.

Nevertheless, the connection between a single impactor and past mass extinctions has been made and popularized widely, and this may be unfortunate considering the issues of more frequent and less "global" events that Clube addresses.

The problem is, as Clube points out, a solitary large impact is, from an astronomical point of view, quite unlikely to be the only agency at work in such extinctions. Further, when one considers the details of the evidence, both astronomical and geological, many discrepancies in the single impactor scenario begin to emerge.

When the Alvarezes, pere et fils, came across the iridium layer at the K-T extinction boundary, announcing that iridium in those amounts could only be thrown up by the impact of a large meteorite, this shocking idea was taken up gleefully by the press and everyone was on the hunt for iridium.

Clube points out that there are several problems with the "single impact" interpretation of the presence of iridium at the extinction boundary. The first problem is that the concentration of the element is too high. Why? Well, because if it were a single, giant impactor, such an asteroid would excavate several hundred times its own volume of Earth crust material and blow it into the atmosphere mixed with its own material. This means that the iridium would be significantly diluted and would not precipitate on the planet in such concentrations as have been found. However, at many of the sites examined, it is noted that the iridium has been diluted by only 20 times its own volume (keeping in mind that the iridium in the comet/asteroid is already only a percentage of the total volume of the extraterrestrial body!)

Additionally, other chemicals associated with the alleged single impact event do not fit the stony meteorite theory very well. There is an abundance of rare elements such as osmium and rhemium; enormous and overabundant common elements such as antimony and arsenic. In respect of this finding, Clube points out that, after a January 1983 eruption of Kilauea, particles collected from the volcano were found to have high concentrations of arsenic, selenium and other elements found in high abundance at the extinction boundary. These volcanic particles were also found to be very rich in iridium. Clube suggests that the iridium anomaly may, therefore, be a big red herring. He notes: "...it is interesting to speculate whether, had a volcanic source of iridium been known in 1980, a meteorite impact would have been suggested" by the Alvarezes?

Probably not.

So, that was probably a good thing because it at least drew press attention to the matter since Clube also points out that there is an impressive amount of evidence that the extinction event was not just a process of evolutionary change and decay. Catastrophic changes - a profound ecological shock - took place across the Cretaceous-Tertiary boundary, and the devastation was certainly sudden. So the Alvarez theory opened the door to consider that in a world that was tightly bound up in Uniformitarianism.

Among the interesting finds at this level of Earth's history is that very large amounts of soot are also present at the extinction boundary. The conclusion is, of course, that global wildfires were raging during the extinction event. The movie tried to depict that with computer models (made on the assumption of a single large asteroid impact) which had the entire atmosphere of the earth heating up to the point where things just ignited spontaneously. That may not be exactly how things happen even with a very large meteor impact.

©Canadian Museum of Nature, Ottawa

The thin clay layer that marks the boundary between the Cretaceous and Tertiary rocks. This layer has been found at many localities around the Earth. It is a a thin layer of material all around the earth which contains a large amount of the rare element iridium, plus soot from widespread fires.

Another point that Clube makes is that there is not a trace of meteoritic debris in the form of stony inclusions in the sediments.

I won't go into all the details; suffice it to say that it begins to look like the stray impact of a single 10 km wide asteroid is not the cause of the global extinction after all.

What is a realistic scenario?

Clube presents the evidence that this extinction event was an episode of bombardment of many, dozens, hundreds, thousands of cometary fragment and/or meteorite type bodies, some of them large, liberating copious amounts of meteorite dust in the Terran atmosphere, many of them exploding overhead in rains of fire. These swarms would be "swimming" in streams of comet dust - tons of it - which would also be loading the atmosphere and precipitating onto the earth over months and years. The high concentrations of iridium found at the dinosaur extinction boundary at several localities, and the absence of bulk meteoritic debris, are hard to explain in terms of a single big bang but easily understood in terms of zodiacal dust as a provider of the input. Added to this, there is increasing evidence for a multiplicity of impacts at the dinosaur extinction boundary, as well as at other points of global catastrophe such as the Permian - Triassic (P - Tr) extinction event. The swarm theory also easily accounts for the huge amounts of soot at the boundary. An Earth ablaze is within the capacity of an exceptionally intense swarm to produce, but probably beyond that of even a 10km wide single impactor. In short, the extinction of the dinosaurs may very well have been a complex, traumatic, and prolonged affair.

©Unknown

What the dinosaurs saw?

Clube proposes that the Earth itself is a storehouse of information about its interactions with the Galaxy, and that it is the Galaxy itself, and Earth's position in it, that drives the cycles of extinctions mainly because the cycles of events best fit known galactic cycles.

The one thing that stands out from all of the evidence is the importance of very large comets that enter the Solar System and break apart, leaving streams of debris that interact with our planet for millennia after the parent body or bodies have been captured and torn apart by intra-solar system forces. That such bombardments of the earth have occurred at other times is becoming more widely known, witness the work of Richard Firestone, Alan West and Simon Warwick-Smith who have identified the Carolina Bays as "air impact" craters from overhead cometary explosions exactly like that of Tunguska. In fact, similar "craters" were found in the Tunguska region with the exact same morphology. This even has been dated to about 12,500 years ago and was global in extent and cataclysmic in effect. Life on Earth almost came to an end. What is frightening about this even is the sheer numbers of craters - upwards of 50,000 of them.

©Unknown

This image shows numerous craters in Robeson County, North Carolina

©Unknown

Arial photo the Carolina Bays craters

©Unknown

The largest crater in this particular image is approximately 1.4 miles across

Companion Star?

Clube mentions the companion star hypothesis briefly, noting that "Certainly the companion-star hypothesis adopts the central mechanism of the galactic one, namely the creation of comet showers through regular comet cloud disturbances." He then dismisses this as facing "insuperable problems." The "insuperable problems" are the proposed orbital periods for the hypothesized companion star and his idea that there would be far more cratering if the motive mechanism was a companion star. He may be entirely correct and his theory of galactic tides and comet birth in the cold, dark reaches of space certainly deals with the main elements of what we know about our celestial environment. As he notes:

The astronomical framework, grounded in celestial observations, is the basis for the theory of terrestrial catastrophism described here. ... It is in our view essential , if one is to arrive at a true picture, to take account of all the relevant evidence: "hard evidence" in the geologist's sense has to be coupled with some respect for hard astronomical facts as well. Put another way, we do not need a 1 - km asteroid to land in our presence to demonstrate the amount of kinetic energy it will release. In particular, the correct picture must explain recent as well as past events in the terrestrial record. Thus the giant comet, and indeed the historical record, are essential elements in the quest for overall truth. It is this inextricable linkage between the very recent and the very remote past which lends urgency to the study: if we get the grand picture wrong, the next set of old bones in the ground could be ours.

We have presented some good evidence in this series of articles that Clube's ideas are very likely correct or darn close: the earth has been repeatedly and regularly showered with extraterrestrial debris of some sort, and these showers have been generally disastrous from local scales, to regional, national, and even continental. It seems clear from the evidence that history itself is not a process of evolution, but more often, devolutionary as each cosmic crisis has either resulted in "survival of the lucky," as opposed to the fittest, and the more recent ones have been amplified or utilized by ruling elites to pursue their own agendas. On other occasions, the Earth has suffered insults that have hardly turned a head in the human population. Tunguska was one such event.

Tunguska

Just after 7:15 a.m. local time on 30 June 1908, in the central Siberian plateau, there took place an impact of ferocious intensity. Yet so isolated and vast is this region (half as large again as the USA), it was almost twenty years before the Western world became aware of the event.

©Unknown

How the Tunguska object may have appeared.

On the night of 30 June and 1 July, the sky throughout Europe was strangely bright. Throughout the United Kingdom, over 3000 miles from the point of impact, it was possible to play cricket and read newspapers by the glow from the night sky. From Belgium came descriptions of a huge red glow over the horizon, after sunset, as if a great fire was raging. This strangely bright sky was seen throughout Europe, European Russia, Western Siberia and as far south as the Caucasus mountains. Photographs were taken at midnight or later, with exposures of about a minute, in Sweden, in Scotland, and as far east as the university city of Kazan, on the banks of the river Volga....

Much comment was excited in newspapers and learned journals at the time. Some thought that icy particles had somehow formed high in the atmosphere and were reflecting sunlight. Others considered that a strange auroral disturbance was involved. The Danish astronomer Kohl drew attention to the fact that several very large meteors had recently been observed over Denmark and thought that comet dust in the high atmosphere might account for the phenomenon. But there was no agreement as to what had happened.

Over 500 miles to the south of the fall, a seismograph in the city of Irkutsk near Lake Baikal, close to the Mongolian border, registered strong earth tremors.

Nearly 400 miles south-west of the explosion, at 7:17 a.m. on 30 June, a train driver on the Trans-Siberian express had to halt the train for fear of derailment due to the tremors and commotion.

Fierce gusts of wind were felt in towns 300 to 400 miles away.

In an Irkutsk newspaper dated 2 July it was reported that, in a village more than 200 miles from the Tunguska river, peasants had seen a fireball brighter than the sun approach the ground, followed by a huge cloud of black smoke, a forked tongue of flame and a loud crash as if from gunfire.

"All the villagers ran into the street in panic. The old women wept and everyone thought the end of the world was approaching."
[...]

Local Siberian newspapers carried stories of a fireball in the sky, and a fearful explosion, but by the autumn of 1908 these stories had died out, and they went unnoticed in St. Petersburg, Moscow and the west. The region was arguably one of the most inaccessible places on Earth, in the centre of Siberia. ... However, rumours of an extraordinary event persisted, transmitted back by geologists and other intrepid researchers working in the area. These attracted the attention of a meteorite researcher, Leonard Kulik,... It was not until 1927 that an expedition ... led by Kulik, finally penetrated to the site of the 1908 explosion.
[...]

The energy of the explosion has been calculated from the extent of the flattened forest and from the small pressure waves which arrived at the speed of sound and were recorded on barographs around the world. ... The wave trains were unlike any others which had been recorded up until that time but resemble those obtained from a hydrogen bomb explosion. It seems that the impact had an energy of 30 to 40 megatons, about that from a few dozen ordinary hydrogen bombs....

The date of fall (30 June) corresponds to the passage of the Earth through the maximum of the Beta Taurid stream. From this and its trajectory, it appears that the Tunguska object was part of the Taurid complex. Probably the Earth passed through a swarm within the stream.

©Unknown

Aftermath of the Tunguska explosion

©Unknown

Aftermath of the Tunguska explosion

©Unknown

This image shows the directions of the blast

©Unknown

This diagram shows the area of damage in Tunguska as compared to the size of Washington D.C.

The occurrence, this century, of an impact with the energy of a hydrogen bomb does give cause for some concern, and it is interesting to speculate on whether one's historical perceptions would be quite the same had the bolide struck an urban area or a city. As it happens, however, the Tunguska impact is fairly trivial:

In this year, on the Sunday before the Feast of St. John the Baptist, after sunset when the moon had first become visible a marvelous phenomenon was witnessed by some five or more men who were sitting there facing the moon. Now there was a bright new moon, and as usual in that phase its horns were tileted toward the east; and suddenly the upper horn split in two. From the midpoint of the divisin a flaming torch sprang up, spewing out, over a considerable distance, fire, hot coals, and sparks. Meanwhile the body of the moon which was below writhed, as it were, in anxiety, and, to put it in the words of those who reported it to me and saw it with their own eyes, the moon throbbed like a wounded snake. Afterwards it resumed its proper state. This phenomenon was repeated a dozen times or more, the flame assuming various twisting shapes at random and then returning to normal. Then after these transformations the moon from horn to horn, that is along its whole lengthe, took on a blackish appearance. The present writer was given this report by men who saw it with their own eyes, and are prepared to stake ther honour on an oath that they have made no addition or falsification in the above narrative.

This curious report is written in the chronicles of the medieval monk known as Gervase of Canterbury. The year of the event was AD 1178 and the date, 18 June on the Julian calendar, converts to the evening of 25 June on the modern Gregorian one. If real, it is clear that some extraordinary event on the Moon is being described and the meteorite expert Hartung proposed that what was observed and recorded 800 years ago was the impact of a body on the Moon. The flame, he suggested, was the writhing of incandescent gases, or sunlight reflection from dust thrown out of the crater. The blackish appearance of the Moon along its whole length was a temporary suspension of dust buoyed up by a transient atmosphere. [...]

Hartung deduced that if there was a crater, it would be at least 7 miles in diameter, possess bright rays extending from it for at least seventy miles, and would lie between 30 and 60 degrees north, 75 and 105 degrees east on the Moon. ...

As it happens, there is one crater with the predicted characteristics exists, a crater named after the seventeenth-century heretic Giordano Bruno. This crater is located at 36 degrees N and 105 degrees E, within the predicted area. It is 13 miles in diameter and is distinguished by its remarkable brightness, and by the brilliant system of rays which extend several hundred miles out from it. [...]

©Unknown

Giordano Bruno crater on the Moon has a diameter more of more than 13.6 miles or 22 kilometers

©Unknown

Giordano Bruno crater on the Moon

It should be noted that NASA has attempted to debunk Hartung's theory, saying:

Such an impact would have triggered a blizzard-like, week-long meteor storm on Earth -- yet there are no accounts of such a storm in any known historical record, including the European, Chinese, Arabic, Japanese and Korean astronomical archives.

Well, we know from our current survey that this is not necessarily so. There could have been impacts on the earth that no one knew about - witness Tunguska - and it doesn't necessarily follow that an impactor on the moon would trigger a blizzard of meteors on Earth.

Back to Clube:

It is the fate of all species to become extinct and most manlike species have already done so. Over and above extinction, large population fluctuations take place in nature, sometimes within a few years. The controlling factor is often climate, and Earth's climate, in turn, can be greatly affected by its astronomical surroundings.

It has been suggested that the current "climate change" issues are due to the earth moving through cosmic dust clouds. It could even be that such things as "chemtrails" are a result of such dust loading in the upper atmosphere.

The two and a half centuries which lay between the Gervase chronicle of 1178 and the onset of the Black Death in Europe in 1348 saw 'an acute crisis developing in human affairs'. One chronicler at least reports of the most immediate cause of the plague in 1345 that "between Cathay and Persia there rained a vast rain of fire; falling in flakes like snow and burning up mountains and plains and other lands, with men and women; and then arose vast masses of smoke; and whosoever beheld this died within the space of half a day..." There seems little doubt also that a worldwide cooling of the Earth played a fundamental part in the process. The Arctic polar cap extended, changing the cyclonic pattern and leading to a series of disastrous harvests. These in turn led to widespread famine, death and social disruption.

In England and Scotland there is a pattern of abandoned villages and farms, soaring wheat prices and falling populations.

In Eastern Europe there was a series of winters of unparalleled severity and depth of snow. The chronicles of monasteries in Poland and Russia tell of cannibalism, common graves overfilled with corpses, and migrations to the west.

Even before the Black Death came, then, a human catastrophe of great proportions was under way in late medieval times. Indeed the cold snap lasted well beyond the period of the ... plague. A number of such fluctuations are to be found in the historical record, and there is good evidence that these climatic stresses are connected not only with famine but also with times of great social unrest, wars, revolution and mass migrations.

In spite of their traumatic effects, these global coolings probably amounted to no more than about a degree in average summer temperatures as compared with today: even relatively minor climatic effects have had a profound influence on human history. A major climatic cooling amounting to several degrees. With the modern dependence on 'green revolution' crops, finely tuned to give a high yield under a narrow range of climatic conditions, the onset of such a 'winter' would cause the population of the world to crash in the course of a decade, or even a single year. Such events are completely outside normal experience and their existence is not generally recognized, even though they represent a hazard vastly more horrific than any of the more familiar catastrophes such as earthquake, famine or flood. ... More to the point though, civilization is in the presence of a hitherto unrecognized cosmic phenomenon which could plunge it without warning into a Dark Age.

What can be done?

Unfortunately the extent and epoch of the next cosmic winter depend for the moment on a number of imponderables which lie outside the scope of existing knowledge: it is not now possible to make an accurate assessment of what the future has in store. This is clearly not a satisfactory state of affairs. Nor can we expect that Nature will hold back on account of our ignorance or lack of preparedness. However, in view of the seriousness of cosmic winters for human survival, and noting the vast expenditures to the tune of many billions of dollars on a whole variety of preparations for all manner of lesser hazards and calamities, both man-made and natural, disease and nuclear war not excluded, one must surely note also that not a single cent of taxpayer' money is currently devoted to their study. [...]

The first step must therefore be one of exploration. An asteroid in a Taurid orbit, carrying 100,000 megatons of impact energy, coming out of the night sky, would be visible in binoculars for about six hours before impact. By the time it was a naked-eye object it would be at most half an hour from collision. In its final plunge it would be seen as a brilliant moving object for perhaps 30 seconds. One needs more time than this to prepare for the [Cosmic] Winter. A thorough exploration of the Earth's surroundings, and the discovery and tracking of probably tens of thousands of bodies, is therefore a first requirement. This is technically feasible.

Complementing such an observational programme, a fresh exploration of the past, armed now with the new astronomical understandings, is also necessary; not just for its own sake but also to arrive at a better understanding of the risks. .[...]

To go from mere statistical projection to detailed forecasting, then, a generation of exploration, both of the Earth's environment and of our history and prehistory, will be necessary. As we have remarked, such studies cannot be seen only as an academic game: there is nothing academic about a 1,000 megaton impact, and the modern prospects for nuclear error, not to mention nuclear meltdown, exacerbate the issue.

And if the sirens should sound, what then? It may be marginally within the capacity of present day technology to divert a small asteroid, given enough warning, though not a swarm of them... But at least, unlike our forebears, we have a chance to act: we need no longer be helpless in the hands of the gods. The main problem at the moment is to be aware that there is a problem.

Three thousand years ago, in accordance with age-old practice, the kings of Babylon were still employing astronomer-priests to give warnings of cosmic visitations. A thousand years ago, the emperors of China were still relying on similar skills, while in Europe the Pope saw messages in the sky and urged Holy War. But this latter was an aberration; for the last two and a half thousand years have seen the decline and fall of the sky gods, and the growing presumption that the cosmos is stable and regular. The shift of paradigm has been unconscious, convenient, insidious and thorough. Probably, the rediscovery of a lost tradition of celestial catastrophe could not have been made through analysis of ancient texts alone; a key had to be provided, and it has been, by the paraphernalia of modern science. It is a salutary lesson both on the capacity of human reasoning to get it wrong for long periods of time, and on the essential unity of knowledge.

It would be naïve to think, however, that one merely has to point to deep-seated cracks in the structure of modern knowledge to have scholars setting to and constructing a better framework within which mankind might plan his future. There is considerable intellectual capital invested in the status quo, enough to ensure that those with an interest in preserving it, the 'enlightened' and the 'established', will continue to present the cosmos to us in a suitably non-violent form. The history of ideas reveals that some will even go further and act as a kind of thought police, whipping potential deviants into line. For them, temporal power takes precedence over the fate of the species. (Clube, The Cosmic Winter)

Famed astronomer, Fred Hoyle, friend and colleague of Clube, made some interesting remarks in his book: "The Origin of the Universe and the Origin of Religion" along the same lines.

Science is unique to human activities in that it possesses vast areas of certain knowledge. The collective opinion of scientists in these areas about any problem covered by them will almost always be correct. It is unlikely that much in these areas will be changed in the future, even in a thousand years. And because technology rests almost exclusively on these areas the products of technology work as they are intended to do.

But for areas of uncertain knowledge the story is very different. Indeed the story is pretty well the exact opposite, with the collective opinion of scientists almost always incorrect.

There is an easy proof of this statement. Because of the large number of scientists nowadays and because of the large financial support which they enjoy, uncertain problems would mostly have been cleared up already if it were otherwise. So you can be pretty certain that wherever problems resist solution for an appreciable time by an appreciable number of scientists the ideas used for attacking them must be wrong.

It is therefore a mistake to have anything to do with popular ideas for solving uncertain issues, and the more respectable the ideas may be the more certain it is that they are wrong. [...]

Another big one for the book is the origin of life, which according to respectable opinion happened here on the Earth. Imagine the Earth's history to be represented by a single day. Then the origin of life did not occur in the last 20 hours because there is fossil evidence that life has existed over the last 20 hours. Nor did life originate in the first 3 1/2 hours, because in this early period the Earth was so heavily bombarded by missiles from outside that even rocks were pulverized so violently as to be unable to preserve their integrity. So life, if it originated on the Earth, did so between 03:30 a.m. and 04:00 a.m. We therefore ask for the evidence that the amazing biochemical miracle of the origin of life happened in this comparatively brief window in the Earth's history. A few sedimentary rocks have survived from it, but they have unfortunately been heated so much that any fossil evidence of life and its origin which might have existed have been lost. Thus the evidence for the respectable popular belief is nil.

This is one remarkable aspect of the popular belief, that it is founded on nothing.

The other remarkable aspect is the intensity of the opprobrium one incurs if one denies it. Only a little biochemical knowledge is needed to see this is yet another situation to set the cats in an uproar.

Biology is replete with them. We are told that natural selection acts to spread small advantageous mutations and operates to suppress disadvantageous bones. But small changes must be frequent if a species is to go anywhere much, in which case the bad and the good are superposed on each other, and how then does natural selection manage to separate them? With the bad generally accepted to be more frequent than the good, all natural selection can do, in simple replicative systems at any rate, is to minimise the rate at which things get worse.

You would think this problem would have been addressed with some care, but as far as I can see it never is. The fossil record of the last 500 millions years provides a serious indictment of biological thinking on evolution. It provides ample evidence of small changes and little or none of big changes. So if evolution is correct, as I suspect it to be, the big changes occur swiftly and the small changes slowly, the big changes so swiftly that they cannot be captured by the random moments revealed by the fossil record. As a physicist might put it, evolution takes place through a sequence of delta-functions, not smoothly as according to respectable scientific academies it is supposed to do.

More than a century ago Alfred Russell Wallace noticed that the higher qualities of Man are acausal, like the Universe itself. Where human qualities have been honed by evolution and natural selection there is very little difference between one individual and another. Given equivalent opportunities for training, healthy human males of age 20 will hardly differ in their abilities to run at pace by more than 10 percent between the Olympic runner and the average.

But for the higher qualities it is very much otherwise. From enquiries among teachers of art, Wallace estimated that for every child who draws instinctively and correctly there are a hundred that don't. The proportions are much the same in music and mathematics. And for those who are outstanding in these fields the proportions are more like one in a million. Having made this point Wallace then made the striking argument that, while the abilities with small spread like running would have been important to the survival of primitive man, the higher qualities had no survival value at all.

Perhaps this is not entirely true? Perhaps "higher abilities" had survival value in terms of those individuals who could "read the handwriting on the wall" in a scientifically observational way? Or, more speculatively, perhaps higher abilities could ensure survival by warning an individual that catastrophe was on its way thereby enabling them to act in preparation to survive?

Over a span of 12 years spent in the Amazon and in the forests of the East Indies, Wallace is said to have discovered 30,000 new species off his own bat. He lived by shipping his specimens to an agent in London who then marketed them to museums. During most of the time, when he wasn't writing epoch-making papers on biological evolution, he lived with primitive tribesmen. Wallace therefore knew a great deal about the modes of survival of primitive man, probably more than anybody else of his generation and probably more than anybody does today. His views on the matter therefore carry weight. What he said was that in his experience he never saw a situation in which an aptitude for mathematics would have been of help to primitive tribes. So little numerate were they that in 12 years he saw only a few who could count as far as 10.

His conclusion was the higher qualities, the qualities with large variability from individual to individual, had not been derived from natural selection.

Abilities derived from natural selection have small spread. Abilities not derived from natural selection have wide spreads.

[...]

I think the higher qualities must be of genetic origin, the same as the rest. The mystery is that we have to be endowed with the relevant genes in advance of them being useful. The time order of events is inverted from what we would normally expect it to be, a concept that is of course gall and wormwood to respectable opinion. The objection is that it explodes one's concepts, raising all manner of new ideas. Which is exactly what respectability dislikes, because it is only in times of stagnation that respectability flourishes.[...]

Already in 1813, in a lecture to the Royal Society of London, William Wells described the process of evolution by natural selection. In the early 1830's it was being asked how this process might go in detail. Could it explain evolution on a large scale, as in the well-known picture of evolution occurring like a branching tree? General opinion was that it could not, and for a reason that was good and which was never answered in the enthusiasms of the later Darwinian movement.

It was observed that plants and animals always, or almost always, have limited habitats, usually with quite sharp boundaries in which they thrive and outside which they do not.

Why, if evolution could produce very large differences like those between horses, bears and primates, could it not produce the much smaller differences that would serve to enable species to extend their limited habitants?

Why did each species not have the plasticity (as it was called) to spread itself all over the world? The fact that this emphatically was not what happened suggested that, while by selection each species fine-tuned its abilities within the range accessible to it, the range in every case is small, far smaller than would be needed to produce the difference between horses and bears. (Hoyle, The Origin of the Universe and the Origin of Religion)

Hoyle's remarks quoted above certainly raise a lot of questions, but the one that immediately comes to my mind is: are human beings with "higher faculties" mutations? A related question might also be: are psychopaths also mutations in the other direction? But I don't want to divert onto that topic just yet, we'll save it for another article. Again, I want to reiterate what I wrote in the previous article:

If short-period bombardment of our planet by comets or comet dust is a reality (as it increasingly appears to be); and the effects of such an event are deleterious in the extreme; and if we are in fact overdue for a repeat performance of such a visitation (which also appears to be the case); what effect might public awareness of this have on the status quo on the planet at present? Would the bogus "war on terror" not become instantly obsolete and would people across the planet not immediately demand that their political leaders reassess priorities and take whatever action possible to mitigate the threat? And if those political leaders refused to do so and it became known that that this grave threat to the lives of billions was long-standing and common knowledge among the political elite (with all that that implies), what then? Revolution? One last hurrah before the 6th extinction?

Who knows. We only know that this knowledge, in its fullest explication, is being suppressed and marginalized. The reasons for the psychological games and ploys may be interesting to investigate. so that is what we will look at next: Why is Humanity so Deaf, Dumb and Blind?

We'll be coming to that!

Comment: See also: Mass Extinctions - Interruptions in the Orderly Process of Evolution for some great graphics!

Dinosaur Extinction Page
Crater Morphology; Some Major Impact Structures

Fast delivery of meteorites to Earth after a major asteroid collision 

Nature
Nature 430, 323-325
Thu, 15 Jul 2004 16:46 EDT

Very large collisions in the asteroid belt could lead temporarily to a substantial increase in the rate of impacts of meteorites on Earth.

Orbital simulations predict that fragments from such events may arrive considerably faster than the typical transit times of meteorites falling today, because in some large impacts part of the debris is transferred directly into a resonant orbit with Jupiter1, 2. Such an efficient meteorite delivery track, however, has not been verified. Here we report high-sensitivity measurements of noble gases produced by cosmic rays in chromite grains from a unique suite of fossil meteorites3 preserved in approx480 million year old sediments. The transfer times deduced from the noble gases are as short as approx105 years, and they increase with stratigraphic height in agreement with the estimated duration of sedimentation. These data provide powerful evidence that this unusual meteorite occurrence was the result of a long-lasting rain of meteorites following the destruction of an asteroid, and show that at least one strong resonance in the main asteroid belt can deliver material into the inner Solar System within the short timescales suggested by dynamical models.

An asteroid breakup 160 Myr ago as the probable source of the K/T impactor

W.F. Bottke, D. Vokrouhlický, D. Nesvorný
Nature 449, 48-53
Thu, 06 Sep 2007 16:50 EDT

The terrestrial and lunar cratering rate is often assumed to have been nearly constant over the past 3 Gyr. Different lines of evidence, however, suggest that the impact flux from kilometre-sized bodies increased by at least a factor of two over the long-term average during the past approx100 Myr.

Here we argue that this apparent surge was triggered by the catastrophic disruption of the parent body of the asteroid Baptistina, which we infer was a approx170-km-diameter body (carbonaceous-chondrite-like) that broke up 160 (+30/-20)Unfortunately we are unable to provide accessible alternative text for this. If you require assistance to access this image, or to obtain a text description, please contact npg@nature.com Myr ago in the inner main asteroid belt. Fragments produced by the collision were slowly delivered by dynamical processes to orbits where they could strike the terrestrial planets. We find that this asteroid shower is the most likely source (>90 per cent probability) of the Chicxulub impactor that produced the Cretaceous/Tertiary (K/T) mass extinction event 65 Myr ago.

Asteroid breakup linked to the Great Ordovician Biodiversification Event

Nature Geoscience 1/2008
Tue, 01 Jan 2008 17:01 EST

The rise and diversification of shelled invertebrate life in the early Phanerozoic eon occurred in two major stages. During the first stage (termed as the Cambrian explosion), a large number of new phyla appeared over a short time interval approx540 Myr ago. Biodiversity at the family, genus and species level, however, remained low until the second stage marked by the Great Ordovician Biodiversification Event in the Middle Ordovician period.[1, 2, 3]

Although this event represents the most intense phase of species radiation during the Palaeozoic era and led to irreversible changes in the biological make-up of Earth's seafloors, the causes of this event remain elusive. Here, we show that the onset of the major phase of biodiversification approx470 Myr ago coincides with the disruption in the asteroid belt of the L-chondrite parent body - the largest documented asteroid breakup event during the past few billion years[4, 5]. The precise coincidence between these two events is established by bed-by-bed records of extraterrestrial chromite, osmium isotopes and invertebrate fossils in Middle Ordovician strata in Baltoscandia and China. We argue that frequent impacts on Earth of kilometre-sized asteroids - supported by abundant Middle Ordovician fossil meteorites and impact craters[6] - accelerated the biodiversification process.

Introduction

Evidence for an early Palaeozoic major asteroid breakup was already established in the 1960s when recent ordinary chondrites of the L type were shown to commonly have K - Ar gas retention or shock ages of about 450 - 500 Myr (refs 4,5). About 20% of the meteorites reaching Earth today are shocked L chondrites from this event. The finds of more than 50 fossil L-chondritic meteorites (1 - 20 cm in diameter) in Middle Ordovician limestone in southern Sweden show that the meteorite flux was enhanced by one to two orders of magnitude for at least a few million years after the disruption event[6, 7]. The L-chondritic origin of the fossil meteorites is demonstrated by element and oxygen isotope analyses of relict chromite grains as well as by petrographic studies of chondrule textures[6, 7, 8]. Chromite is the only common mineral in chondrites that survives extensive weathering on the wet Earth surface. In the limestone beds containing common meteorites, abundant chromite grains from decomposed meteorites and micrometeorites are also found[9, 10, 11]. Cosmic-ray-induced 21Ne in chromite from the fossil meteorites increases upwards in the strata, supporting a common origin from an asteroid breakup event[12]. High-precision 40Ar-39Ar dating of recent L chondrites has constrained the timing of their parent-body disruption to 470 plus/minus 6 Myr ago, which is identical within uncertainties to the age of 467.3 plus/minus 1.6 Myr ago for the beds with fossil meteorites according to the latest geologic timescale[13].

During the Great Ordovician Biodiversification Event (GOBE), in the Middle to Late Ordovician, biodiversity at the family level increased from a Phanerozoic all-time-low in the Cambrian and Early Ordovician to levels approximately three times higher in the Late Ordovician[1, 2, 3, 14, 15] (Fig. 1). The new biodiversity levels of marine life were matched by an increase in biocomplexity, and were sustained until the end of the Palaeozoic except for short-term declines in connection with extinction events in the latest Ordovician and Late Devonian periods. The GOBE generated few new higher taxa, for example phyla, but witnessed a staggering increase in biodiversity at, for example, species level among a wide variety of groups of skeletal invertebrates[2, 3, 15]. Diagrams of changes in global or regional biodiversity during the GOBE give only a crude representation of the timing and pace of the faunal change[15, 16]. The global signal represents a combination of many regional diversity changes across a range of fossil groups[2, 3]. The most focused global compilation through the early Palaeozoic, shown in Fig. 1, demonstrates a sharp rise in biodiversity at about the Arenig - Llanvirn boundary (about 466 Myr ago). This signal is evident across a number of groups, such as the brachiopods, cephalopods and echinoderms, but less clear in some members of the Cambrian fauna (trilobites) and the modern fauna (gastropods)[15]. It also corresponds to the second-cycle diversity peak in conodonts recognized by Sweet[17]. The causes of the GOBE, and its relation to both intrinsic (biological) and extrinsic (environmental) factors are not known2. Many authors have suggested a link to increasing levels of atmospheric oxygen, favouring the radiation of aerobic metazoan life together with an expansion of the phyto and zooplankton[18, 19].

Figure 1: Global biodiversity change at family level through the early Palaeozoic era.

©Nature

Although this diagram from Sepkoski gives a good representation of the overall biodiversity trend, the resolution is too crude for correlation with field data. Trem.=Tremadocian (Global) and Tremadoc (British), Ash.=Ashgill, Lland.=Llandovery, We.=Wenlock, Lud.=Ludlow, F.=Floian, Dap.=Dapingian, Sand.=Sandbian, H.=Hirnantian.
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Although biodiversity diagrams such as in Fig. 1 show the broad outline of change, at a higher resolution they suffer from the effects of poor correlation and poor preservation of faunas, focus on a particular horizon or group of fossils and data binning. To relate biological change to physical events, detailed high-resolution multiparameter records across complete and fossil-rich sections are required. Here, we have constrained the precise stratigraphic level for the L-chondrite disruption event by searches for sediment-dispersed extraterrestrial (chondritic) chromite grains and Os isotopic studies in Middle Ordovician sections with condensed limestone (Fig. 2). These results are matched by the most detailed bed-by-bed studies of the distribution of brachiopod species across Middle Ordovician strata in Baltoscandia (Fig. 3) conducted until now.

Figure 2: Distribution of extraterrestrial (chondritic) chromite and osmium isotopes through Middle Ordovician sections in Sweden and China.

©Nature

Results are shown for sections at Kinnekulle (Hällekis and Thorsberg quarries) and southern Scania (Killeröd and Fågelsång sections), 350 km apart in southern Sweden, and the Puxi River and Fenxiang sections, 4 km apart in south-central China. The distribution of Os isotopes across the Hällekis section is also shown. The stratigraphic interval yielding abundant fossil meteorites in the Thorsberg quarry is indicated6. The conodont biostratigraphy shown has been produced specifically for this study, using consistent taxonomic concepts for the different sections. M. ozarkodella=Microzarkodinaozarkodella.
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Figure 3: Total diversity of brachiopod species (number of species) through part of the Lower and Middle Ordovician in Baltoscandia.

©Nature

The results are based on bed-by-bed collections at eight localities[22]. Note the dramatic increase in biodiversity (black line) and high extinction (blue line) and origination (red line) levels following the regional Volkhov - Kunda boundary, that is, the same level where extraterrestrial chromite appears and Os isotopes change in Fig. 2. B. triang.-navis=Baltoniodustriangulatus-navis. The dashed lines show the boundaries between the regional states.
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The sections studied for extraterrestrial chromite grains occur at Kinnekulle and in southern Scania, 350 km apart in southern Sweden, and at Puxi River (Puquie) and Fenxiang, 4 km apart in south-central China near Yichang, Hubei province. The extraterrestrial chromite grains (>63 mum) have been retrieved from about 10 - 30-kg-sized limestone samples that were dissolved in HCl and HF acid[10]. The extraterrestrial chromite can be readily distinguished from terrestrial chromite by its distinct element composition[6, 10]. The results of the extraterrestrial chromite searches are shown in Fig. 2 and in the Supplementary Information. In the section studied in greatest detail, at Kinnekulle, in 379 kg of limestone from 14 levels across 9 m of strata below the Lenodus variabilis zone, only 5 extraterrestrial chromite grains were found[10 ](Fig. 2). The values then increased dramatically to typically 1 - 3 extraterrestrial chromite grains per kilogram of rock in the L. variabilis, Yangtzeplacognathus crassus and Microzarkodina hagetiana zones. In this interval, a total of 332 extraterrestrial chromite grains were found in 174 kg of rock. In southern Scania and in China, the distribution trends of extraterrestrial chromite grains are very similar to that at Kinnekulle. In southern Scania, some beds in the L. variabilis zone contain up to 6 extraterrestrial chromite grains per kilogram of rock, whereas only 2 grains were found in 125 kg in the beds spanning 7 m below[11]. In the Chinese sections, 89 kg of limestone below the L. variabilis zone yielded only 1 extraterrestrial chromite grain compared with 117 extraterrestrial chromite grains in 89 kg in the overlying beds (Fig. 2).

The first appearance of common extraterrestrial chromite grains in the lower L. variabilis zone in the three sections is a strong indication of the precise timing of the disruption of the L-chondrite parent body. The data also represent strong support for an increase by two orders of magnitude in the flux of micrometeorites and meteorites to Earth following the disruption event, as previously suggested on the basis of studies of the Swedish sections alone[9, 10, 11]. There is no indication that changes in sedimentation rates, on average a few millimetres per thousand years, can explain the observed major trend in extraterrestrial chromite concentrations, although individual beds may have formed at different rates. That the disruption event occurred in the lower L. variabilis zone is consistent with cosmic-ray-induced 21Ne ages of chromite grains from the fossil meteorites[12]. In 5 - 10-Myr-old younger condensed limestone in the Gärde quarry, central Sweden, we found 9 extraterrestrial chromite grains in 23 kg of rock. This indicates that the extraterrestrial chromite flux is still enhanced compared with that before the asteroid breakup. The low pre-breakup concentrations of extraterrestrial chromite grains are similar to concentrations measured in similarly condensed sediments from much younger periods. For example, in 210 kg of pelagic limestone (average sedimentation rate about 2.5 mm kyr-1) from the famous Late Cretaceous - Paleocene Gubbio section in Italy we found only 6 extraterrestrial chromite grains[20].

Our analyses of 187Os/188Os ratios in whole-rock limestone samples through the Kinnekulle section show a relatively stable trend with ratios around 0.6 - 0.8 through the lower 11 m of section, but from the same bed where the extraterrestrial chromite grains become common and further up, ratios mainly lie in the range 0.3 - 0.5 (Fig. 2; Supplementary Information). The simplest explanation for this prominent change is an increasing influence of an extraterrestrial component (187Os/188Os approx 0.12) at the expense of a detrital/hydrogenous Os component (187Os/188Os approx 0.8) (ref. 21), well in line with conclusions based on extraterrestrial chromite trends.

Some of the best sections for studies of Ordovician invertebrate diversification occur in Baltoscandia[22]. We have established the Middle Ordovician biodiversity trends for brachiopods on the basis of bed-by-bed sampling of more than 30,000 fossils from 8 sections in Baltoscandia (Fig. 3). The phylum Brachiopoda dominated the benthos of the Palaeozoic evolutionary fauna both in abundance and diversity and formed a pivotal part of the suspension-feeding food chains of the era. The phylum was widely dispersed across shallow to deep-water environments around all of the palaeocontinents. We show here that there are two intervals in the succession when the Baltoscandian brachiopod fauna suffered dramatic changes - one within the lower part of the regional Volkhov stage and one at the base of the Kunda stage (Fig. 3). The largest change occurs during exactly the same interval when the L-chondritic extraterrestrial flux peaks at the base of the Kunda stage, and when brachiopods more typical of the Palaeozoic evolutionary fauna, that is, orthides and strophomenides, diversified.

Modelling studies suggest an enhanced flux of extraterrestrial matter, including large asteroids, during 10 - 30 million years after major asteroid disruption events[23]. The L-chondrite parent-body breakup at 470 Myr ago is thought to have created the Flora family of asteroids[24]. These asteroids were particularly prone to enter Earth-crossing orbits because of their position relative to an important orbital resonance[23, 24]. Apparently, the Middle Ordovician interval with enhanced extraterrestrial flux is broadly coincident with the main phase of the GOBE[1, 2, 3, 15]. At least in Baltoscandia, the onset of the two events seems to coincide precisely (Figs 2, 3). Albeit speculative, the best explanation for the coincidence is that frequent impacts on Earth of large asteroids, fragments of the L-chondrite parent body, generated changes in the biota. Impact-related environmental perturbations may have accelerated a process driven also by intrinsic biological mechanisms. Although much contemporary research has focused on the negative effects of large impacts, such as in the Cretaceous - Tertiary boundary case[25], more minor and persistent impacts could generate diversity by creating a range of new niches across a mosaic of more heterogeneous environments. Such diversity increases are predicted by the well-established intermediate disturbance hypothesis, initially applied to diversity changes in coral reefs and tropical rainforests[26]. Frequent impacts may also have destabilized ecological communities, allowing invasive species to take over and displace incumbent communities. The ecological and taxonomic amplitudes of the Middle Ordovician biodiversification may be decoupled and there are important feedback loops in the process. This phase of the diversification is marked by a brachiopod takeover from trilobites in benthic communities, and the establishment of recumbent life modes and size increases in many brachiopod clades. However, in contrast to the carnivores and detritus feeders of the modern fauna, the Palaeozoic fauna was then dominated by a suspension-feeding benthos with low metabolic rates better equipped to deal with and benefit from major environmental disruptions.

There are about 170 known impact craters on Earth and their record shows that impacts may have been more common by a factor of 5 - 10 during the Middle Ordovician compared with other periods of the Phanerozoic[6, 13]. Four of seventeen known impact craters in Baltoscandia (Granby, Lockne, Kärdla and Tvären craters) are of Middle to early Late Ordovician age. For only very few of Earth's craters has it been possible to determine the impactor type, but for at least the 458-Myr-old Lockne crater in central Sweden, chromite in resurge deposits has implicated an L-chondritic impactor[27].

The strata in China and Baltoscandia that we show are rich in fossil meteorites and/or extraterrestrial chromite grains have long been known to include horizons with unusual lithologies. Over several hundred thousand square kilometres in southern Sweden, the succession of homogeneous red orthoceratite limestone is interrupted by a 1-m-thick anomalous grey, clay-rich interval with a peculiar fauna. During deposition of this bed, centimetre-sized cystoids seem to have literally covered the sea floor of a major part of the Baltic Basin. In west Russia, peculiar ooid horizons characterize the interval, and in China, unusual mini-mounds interrupt the normal succession of nodular marl and limestone[28] (Fig. 2). The possible relationship of these anomalous lithologies and structures to asteroid impacts or other astronomical perturbations, such as Solar System gravity disturbances, certainly warrants further studies. As shown here, at least on a regional scale, there is a close temporal coincidence between major biological change and the disruption of the L-chondrite parent body.

Recently, the impactor at the Cretaceous - Tertiary boundary has been tied by modelling to an asteroid disruption event at 160 Myr ago (ref. 29), but this event may not have led to a pronounced asteroid shower as focused in time as the one in the Middle Ordovician, and it has not left any obvious signal in the collision history of present-day meteorites.

Methods

For chromite searches, samples of typically 10 - 30 kg of limestone were crushed and decalcified first in 6 M HCl and then in 18 M HF at room temperature. The acid-insoluble fraction, 63 - 355 mum, was searched for opaque minerals under the binocular microscope. Picked grains were mounted in epoxy resin and polished to a flat surface using a 1 mum diamond slurry. Element analyses were carried out with a scanning electron microscope - energy dispersive spectrometer[9, 10, 11, 27]. The extraterrestrial chromite grains are characterized first by high Cr2O3 contents of approx55 - 60 wt%, FeO concentrations in the range of approx25 - 30 wt%, low Al2O3 at approx5 - 8 wt% and MgO concentrations of approx1.5 - 4 wt%. The most discriminative feature, however, is narrow ranges of V2O3, approx0.6 - 0.9 wt%, and TiO2, approx2.0 - 3.5 wt%, concentrations. For a grain to be classified as an extraterrestrial chromite grain, it has to have a composition within the defined ranges for all elements listed[10].

For Os analyses, whole-rock limestone samples were ground in an agate mortar. Between 3 - 10 g of powdered sediment was weighed, mixed with an isotopically enriched spike containing 190Os, dried at room temperature over night and then mixed with borax, nickel and sulphur powder. After fusing the mixture for 90 min at 1,000 °C, the NiS bead was separated and dissolved in 6.2 M HCl and the residue filtered at 0.45 mum. Insoluble platinum-group-element-containing particles were dissolved in concentrated HNO3 in a tightly closed Teflon vial at approx100 °C. After dissolution, the Teflon vial was chilled in ice water to minimize the escape of volatile OsO4. Osmium was then extracted from this vial with the sparging method directly into the torch of a single-collector inductively coupled plasma mass spectrometer (Finnigan Element). Typical Os blanks are <1 pg g-1. Depending on the Os concentration, the precision in 187Os/188Os is between 0.5% and a few per cent. The details of the method and an evaluation of the accuracy and precision of the data have been published elsewhere[30].

Acknowledgements

This study was supported by financial support to B.S. from the National Geographic Society, Swedish Research Council (VR) and Crafoord Foundation and to D.A.T.H. from the Carlsberg Foundation. This is a contribution to International Geological Correlation Programme project 503.

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Birger Schmitz, David A. T. Harper, Bernhard Peucker-Ehrenbrink, Svend Stouge, Carl Alwmark, Anders Cronholm, Stig M. Bergström, Mario Tassinari & Wang Xiaofeng







Reinventing Darwin Again: How Asteroids Impacted Human Evolution 

Robert Roy Britt
Space.com
Sat, 21 Apr 2001 01:39 EDT

In the 5 million years or so that it took for apes to become human, many human-like branches of the evolutionary tree were lopped off. Scientists have long wondered why these other hominid species, estimated to number a dozen or more, didn't make it.

Were those who came to travel to the Moon and ponder their very origin the logical and inevitable victors in the most important of all Darwinian struggles?

Or did we just get lucky?

A newly presented mathematical argument suggests that the birth of Homo sapiens was guided by catastrophic asteroid or comet impacts, which created climate conditions that competing species, frankly, couldn't handle.

It also holds that our human ancestors avoided early elimination by the statistical skin of their rotting teeth.

"The reason that Homo sapiens have survived in spite of these global disasters has little to do with the traditional explanations given by neo-Darwinists," said Benny Peiser, a social anthropologist at Liverpool John Moores University. "It is sobering to realize that we are alive due to cosmic luck rather than our genetic makeup."

Peiser bases his argument on the fact that populations of hominids and early modern humans were extremely small. "Had any of these impacts occurred in the proximity of these population groups, we might also have gone the way of the dodo," he said.

The study's assumptions and calculations have met with strong caution and even sharp criticism among scientists who specialize in evolution, as well as asteroid experts.

Adaptive advantage

David Balding, a professor of applied statistics at University of Reading in the U.K., said the idea that human survival is due to "cosmic luck" does not compute:

"Perhaps we were lucky in avoiding a massive impact, but perhaps it was our adaptive advantage that helped us survive modest regional impacts whereas our hominid cousins did not," said Balding, whose own research focuses on human evolution.

But some called the new scenario plausible. It has not been published in a peer-reviewed journal but it is based on impact estimates that are generally accepted by the asteroid research community, though there are disagreements over the precise number of times a large asteroid or comet has struck our planet.

Peiser laid the idea out earlier this month at a conference, "Celebrating Britain's Achievements in Space." He worked with Michael Paine, a volunteer for the Planetary Society in Australia who ran impact scenarios through a computer program. (Paine has written freelance stories for SPACE.com in the past.)

The researchers concluded that there would have been 20 "globally devastating" impacts during the past 5 million years, with effects strong enough to have had "a catastrophic and detrimental effect" on human evolution. Five million years ago is roughly the time when hominids diverged from other apes, though some recent controversial evidence puts the split as far back as 6 million years ago.

Did space rocks set the human stage?

No one argues that asteroids can be devastating when they tangle with Earth. An impact 65 million years ago is widely believed to have spurred the demise of the dinosaurs and many other animals and plants.

But efforts to tie other, more ancient mass extinctions to impacts remain inconclusive. While extinctions are clearly identifiable in fossil records, impact evidence seems not to survive the millennia as well. So impact estimates are based largely on the Moon -- a nearby archive of countless craters that have not eroded much over time.

Still, because scientists have not witnessed a severe impact, the presumed effects are speculative.

If an asteroid larger than a kilometer (0.6 miles) hit the planet, it would cause instant death across a wide area near the site of impact, and researchers generally agree that drastic climate changes could last a year or more. Even our protective ozone layer could be damaged, studies have shown.

But the precise consequences of these effects are not known. It is thought that long-term climate change could make life impossible for many species, which in turn would cause mass death that might move up entire food chains.

Peiser suggests another possible effect: "The abrupt loss of the ozone layer and the sudden release of toxins may even affect the DNA in some unknown manner, thus triggering macro-mutations, including the sudden reorganization of entire genomes."

Ellen Thomas, a Wesleyan University research professor who examines how climate change affects evolution, said few evolutionists would by this argument of quick, significant changes in the genetic blueprints. Instead, macro-mutations are seen by many as a genetic dead end.

"Macro-mutations can hardly ever lead to evolution," Thomas said. "They lead to non-viable organisms."

Basic numbers questioned

Of course to affect human evolution in any fashion, a space rock first has to hit Earth. But "no one knows how many impacts took place, or when, or with what severity, over the past 5 million years," said David Morrison, an asteroid expert at NASA's Ames Research Center in California.

Morrison told SPACE.com that instead of the 20 potentially devastating impacts assumed by the study, he expects there were probably only five or 10 with enough energy to create global environmental effects.

"But we know very little about specific impacts in this time frame, and virtually nothing at all about their actual environmental effects," Morrison said, adding that there is "no evidence of an impact associated with a hominid extinction."

Morrison did not discount the whole idea, however.

"I would be surprised if impacts had not had some influence on early hominid populations and perhaps evolution," he said. "On the other hand, I am not convinced that impacts led to numerous extinctions in the past 5 million years. This is all interesting speculation, but specific data are lacking on either impacts or extinction events and there is no known correlation between the two."

Peiser counters that the estimates used in the study are "very conservative." He acknowledges that shortcomings in the human fossil record (fossils on land erode more easily than those in the oceans) "are far too big to allow any direct correlation between impact catastrophes and hominid extinction." But he said that the study shows that "impact catastrophes that occurred during the crucial period of human evolution should no longer be ignored."

Still, it is clear that more research will be needed before any consensus emerges.

"What [Peiser and Paine] may have added," said Balding, the statistics professor, "is some quantitative simulations to make more precise some well established speculations."

Speculation about evolution is nothing new. And the more one delves into the nitty-gritty of our own past, the stronger the criticism gets over Peiser's attempt to reinvent Darwin.

Does Darwin need reinventing again?

If asteroid experts are sometimes a mile apart on their view of history -- and they are -- then evolutionary theorists live on different continents.

Followers of Charles Darwin have long believed that failed branches of our ancestry reflect a common mode of evolution, whereby species are gradually replaced by more advanced species that adapted because of their superior genetic fitness.

But in recent decades, a different view called punctuated equilibria has taken hold. This theory, first put forth in the 1970s by Stephen J. Gould and Niles Eldredge, expects sharp changes in evolution.

In either scenario, luck plays a role. And both fit within the most famous of Darwinian themes, survival of the fittest. But the rapid shifts assumed in punctuated equilibria, be they caused by sudden disasters or other means, are thought to be the mechanism by which one species replaces another.

"There has been debate for over 100 years on whether evolution is gradual or punctuated," said Balding.

And the debate continues. Recent fossil findings have some researchers leaning back toward the gradual approach to human evolution.

Peiser said his study supports punctuated equilibria, and helps explain why "almost all hominids, i.e. the 14 known species of human ancestors, have become extinct during the last 5 million years."

But Wesleyan's Ellen Thomas said it is not even known that there were 14 species.

"The human fossil record is incomplete, and it is not easy to agree on which fossils belong to different species," Thomas said in an e-mail interview. "The experts disagree wildly."

Thomas echoed other scientists in pointing out that there is no fossil evidence -- neither of human remains in Africa nor marine organisms, which leave a much more complete record -- that reveal any mass die-offs during the 5 million-year period covered in Peiser's study.

"And if the extinctions affected humans, they should show up in the extinction record of other organisms as well," Thomas said. "The paper just shows that many impacts, many of which could have been damaging, possibly occurred."

But Peiser argues that no expert on near-Earth asteroids, the space rocks known to exist in our region of the solar system, questions that "many such global disasters must have occurred." Yet he said "all textbooks on human evolution completely ignore the occurrence of catastrophic impacts."

Other forces of evolution

While Peiser and Paine suggest that comets or asteroids are a driving force behind evolutionary change, it is the climatic consequences of impacts that are the would-be crushing mechanisms for fledgling species. Other researchers have long debated possible links between climate change and human evolution.

For example, cold periods are suspected of forcing migrations that created small, isolated groups that could have evolved significantly but then died out. One such period may have occurred as recently as 71,000 years ago. But firm links between climate and serious evolutionary changes elude researchers.

One recent international study, released earlier this year and led by Jeremy Marlow of Newcastle University, showed evidence of a significant cooling of the climate 2 million years ago that the authors said "adds weight to the theory that climate change played a significant part in the evolution of early humans."

Further clouding the possibilities, recent findings have hinted at the possibility that the worst extinctions might require multiple killing mechanisms, such as when an impact, or perhaps several, happens to occur during a time of heavy volcanic activity.

Irony in our existence

In an ironic preface to the whole argument, it's possible that asteroids and comets were responsible for life in the first place. A growing movement among astrobiologists suggests that rocks from space brought critical building blocks that stimulated the initial biological activity in the earliest primordial soup billions of years ago.

But regardless of whether cosmic messengers helped make us who we are, there is one thing researchers seem to agree on: Given the evidence that our ancient ancestors were clustered in a relatively small area (in Africa) you are somewhat lucky to be reading about all this.

"Asteroids certainly had the opportunity to wipe out man at his roots," said Jack G. Hills, an asteroid specialist at Los Alamos National Laboratory. "Only good luck prevented it."

Details of the New Idea

The following details of the new idea were provided by Benny Peiser and Michael Paine and appear here with only minimal editing for style and clarity:

The findings are calculated on the basis of the generally accepted "impact rate" (i.e. the rate of cosmic impacts calculated from terrestrial and lunar impact craters together with the currently observable flux of asteroids and comets in the solar system). A computer simulation of cosmic impacts over a 5 million-year period was chosen to give an indication of the environmental disruptions that have occurred during the evolution of our species.

These consequences can be categorized into:

A. Local -- devastation over a radius of tens of (miles) kilometers. No serious regional or global consequences

B. Moderate regional -- devastation over a radius of hundreds of miles (kilometers) -- the size of a small country. Short-term regional climatic problems.

C. Severe regional -- devastation over 600 miles (1,000 kilometers) (the size of a large country). Severe regional climatic disruption. Mild, short-term global climatic disruption -- year without summer.

D. Moderate global -- devastation over thousands of miles (kilometers) -- continental. Severe global climate disruption lasting several years. Global food chain failures

E. Severe global -- global firestorms from ballistic entry of impact debris. Extreme worldwide climate disruption for decades to centuries. Extinctions.

For everything except the last category, the effects on early human populations depend on proximity to the impact -- a matter of luck. In addition to climate disruption (mainly darkness and cooling), the larger impacts could lead to global warming due to the greenhouse effect (water and carbon dioxide), loss of the ozone layer (particularly with ocean impacts that propel chlorine into the upper atmosphere), acid rain and toxins.

The simulation looked at the worst event in each of 5,000 millennia. It therefore gives an underestimate of the total number of impacts.

The program recognizes five outcomes of an asteroid or comet colliding with Earth:

* The object skims the atmosphere and flies harmlessly back into space. This happened in 2 percent of the millennia.
* The object explodes above land in an airburst similar to an atomic explosion. This happened in 17 percent of the millennia.
* The object impacts the land and forms a crater. This happened in 11 percent of the millennia.
* The object explodes in an airburst above an ocean. This was the most frequent outcome, accounting for 41 percent of millennia. Fortunately, until recently, most of these impacts would have been harmless to land dwelling creatures.
* The object impacts the ocean, forming tsunami and, possibly, ejecting vast quantities of water and salt into the atmosphere. This happened in 28 percent of the millennia. (Larger impacts may also reach the ocean floor and cause similar effects to a land impact)

Over the period of the simulation some 57 percent of millennia suffered an impact that would potentially have consequences for land-dwelling creatures. In most cases they would only be affected when they were close to the impact site. The situation is different now with significant human populations living in low-lying coastal areas.

Size impactor (The letters refer to the typical environmental consequences.)

1,650 to 2,950 feet (500 to 900 meters) (C): 108 events

0.6 to 0.9 miles (1 to 1.5 kilometers) (C/D): 24 events

1 mile (1.6 kilometers +) (D/E): 13 events

Craters (The letters refer to the typical environmental consequences.)

Over the 5,000 millennia a total of 552 craters were formed on land. Of these:

* 477 were less than 3 miles (5 kilometers) in diameter (A);
* 64 were between 3 and 6 miles (5 and 10 kilometers) in diameter (B);
* nine were between 6 and 12 miles (10 and 20 kilometers) in diameter (C);
* two were more than 12 miles (20 kilometers) (D).

There were also six ocean impacts that could be expected to produce moderate-to-severe global climate disruption (D/E), particularly destruction of the ozone layer. Three of these involved transient craters more than 31 miles (50 kilometers) in diameter and would probably have penetrated to the ocean floor.

Therefore, during this simulation severe climate disruption occurred, on average, every million years (i.e., two land impacts and three ocean impacts).

The findings by Peiser and Paine are underpinned by a significant number of large impact craters. So far, 32 impact craters have been discovered that are younger than 5 million years. One is 32 miles (52 kilometers) in diameter, three are between 6 and 12 miles (10 and 20 kilometers), one is between 3 and 6 miles (5 and 10 kilometers) and 25 are less than 3 miles (5 kilometers) in diameter. However, it should be noted that it takes very unusual conditions to preserve craters of this size for more than a few hundred thousand years.

Additional background material is provided by the authors here.

Comment: One thing is asteroids of which there are relatively little chance of impact. Another thing which was highlighted by Victor Clube and has been documented in a series of articles by Laura Knight-Jadczyk in the last week or two, is the threat by cometary showers, which appear to be cyclical and much much more frequent visitors to planet Earth than asteroids. What also appears evident is that this information is being severely repressed by the powers that be.

See the articles on "comets and catastrophe" using the links to the left of this article.

Astronomers discover first near-Earth triple asteroid

ANI
Thu, 14 Feb 2008 08:38 EST

Astronomers have discovered the first near-Earth triple asteroid, which is hardly 7 million miles from our planet.

Known as 2001 SN263, the asteroid, with three bodies orbiting each other, was discovered by astronomer Michael C. Nolan and his colleagues using the sensitive radar telescope at Cornell University's Arecibo Observatory in Puerto Rico.

The main, central body is spherical with a diameter of roughly 1.5 miles (2 kilometers), while the larger of the two moons is about half that size. The smallest object is about 1,000 feet across, or about the size of the Arecibo telescope.

Other triple asteroids exist in the asteroid belt (between Mars and Jupiter) and beyond, but this is the first near-Earth system where the actual shapes of objects can be clearly seen.

"This discovery has extremely important implications for ideas about the origins of near-Earth asteroids and the processes responsible for their physical properties," said Nolan.

"Double, or binary, asteroid systems are known to be fairly common - about one in six near-Earth asteroids is a binary - but this is the first near-Earth triple system to be discovered," he added.

The orbits of binary and now triple asteroid systems unveil the mass and allow astronomers to assess whether they are stable over millennia or have formed very recently.

According to Nolan, because of the small sizes and irregularly shaped components, 2001 SN263 should offer unique insights relative to the much larger triple systems in the main asteroid belt.

"Examining the orbits of the moons as we continue to observe 2001 SN263 over the next few weeks may allow us to determine the density of the asteroid and type of material from which it is made," said Nolan.

"We will also be studying its shape, surface features and regolith (blanketing material) properties," he added.

UK: What was spotted in skies above Grantham?

Jo Hall
Grantham Journal
Tue, 12 Feb 2008 09:42 EST

Strange astronomical sights have been reported in the skies above Grantham this weekend.

Whether they were UFOs, space shuttles or just frenzied meteorical activity, no one is sure.

On Saturday night, at about 7.45pm, what looked like a spacecraft with a blazing orange trail was reported to have passed over the town.

The following night, between 9pm and 9.30pm, Shelley Jones was walking home when she spotted five large meteors fly across the sky.

She said: "We spotted the first one at 9pm.

"It came from the south heading north - each one on exactly the same trajectory and at approximately four to five-minute intervals.

"Each became slightly larger and brighter than the first. The final one was huge like a large ball of fire in the sky moving towards the north."

Unfortunately, Shelley was unable to catch any of the activity in the skies on camera, but she can't believe her and her husband were the only ones to see it.

Comments:

A Journal website reader who did not want to be identified contacted us to say she saw something similar a fortnight ago when she was walking her dog in Sleaford.

She said: "I saw the same orange flying ball.

"I thought it was a comet or a shooting star at first and thought it was quite low and lasting a long time.

"It went over me and headed for the town centre from Grantham direction. I carried on walking and about five minutes later it was back over the top of me and stayed there for a while and then changed direction and headed toward Lincoln direction.

"From underneath, it looked like it was on fire but the flames looked as if they were some kind of liquid and there was no noise.

"I thought I was going mad and I wish I'd had my camera with me. I'm glad I'm not the only one to see this."

UK: Meteorite shoots over Battle 

Laura Button
Rye and Battle Today
Wed, 13 Feb 2008 07:35 EST

There was a spectacular site in the skies above Battle on Monday night as a suspected meteorite shot over the town before appearing to explode.
Hastings resident Mary Lincon was gazing at the constellations between 10.30-11pm when she saw a 'huge glow' in the night sky.

Mary said: "I presume I was witnessing a meteorite falling through Earth's atmosphere when I was looking at the constellations of Taurus and Orion.

"The scale was far larger than any shooting star that I have seen in the past."

She added: "It was a deep red/orange colour surrounding a dark inner core, with no long trail as you would expect a piece of solid material to appear when burning at a high speed.

"It was curving in a relatively small arc that I spotted just to the lower right of Taurus travelling to the east past Orion, before it appeared to explode and fragment and before it hit the horizon."

Mary is keen to hear if anyone else witnessed the spectacle or may have found a fragment of the meteorite.

- Did you see the meteorite or any other strange happenings in the skies over Battle? Call the newsdesk on 01424 856783.

Large Fireball over Normandy Beach New Jersey 

ny-spi.com
Sat, 01 Sep 2007 17:59 EDT

September 1, 2007 (Evening)

Multiple-witness sighting of large fireball and other unidentified object(s) flying from West to East over the NJ shoreline. Object(s) were reported to have allegedly crashed into the Altantic Ocean. Local police and U.S. Coast Guard search missions were dispatched by boat, helecopter, and on the beach.

Investigator Comments...

Oliver Kemenczky:

"The Normandy Beach sightings of September 1, 2007 were witnessed by dozens of people at many different locations along the Eastern U.S. seaboard, from as far North as Long Island, New York to possibly as far South as South Carolina. Telephone calls were received by police, fire department, and Coast Guard officials during the 8:30 PM to 11:30 PM timeframe. The event, involving a fireball and other unidentified aerial objects, was reported on radio and television newscasts, as well as in new many newspapers and on the Internet. NY-SPI's primary investigation focused on the actual location where objects were reported to have "crashed" into the Altantic Ocean and in the area from where the Coast Guard search had occurred. The Coast Guard search encountered no debris on the surface of the water.

NY-SPI obtained the exact coordinates of the Coast Guard's search missions (provided to us by the C.G.) and subsequently embarked on a search of the ocean floor beneath the water. Our investigation team was equipped with a diver, sonar, magnetometer, GPS, radar, an underwater camera, and other search instrumentation. The team did not have high expectations of actually finding or recovering what may have crashed into the water, understanding that it was like looking for a needle in a haystack. Assuming the search coordinates provided were correct and assuming the object we were looking for had actually crashed in the area that we had searched, there were still many possiblilties that could have caused us to come up empty-handed. For example, the proposed object may have embedded itself beneath the sand on impact; or clam boats trawling the ocean floor may have buried it; or perhaps whatever the object was (as witnessed on the water with the red beacon) may have sunk and already been quietly recovered before we got there. Nonetheless, we proceeded with our search and the case remains and open mystery. Additional witnesses have come forward to NY-SPI with their accounts since the investigation was filmed."

Ted Davis:

"Beach closings, beached mutilated fish, an unidentified aircraft crashing into the ocean, an exploding fireball, a Coast Guard rescue mobilization and a stir of media reports. This sounds more like a case from the X-Files than a real life UFO sighting that shook the picturesque beach communities along the New Jersey shore right before Labor Day in the late summer of 2007.

The initial media buzz surrounding this case was quite substantial, drawing our attention only a day or two after it first occurred. Numerous stories in print and on the internet cited the local authorities and Coast Guard as receiving high volumes of calls on the night of the incident. However, when NY-SPI contacted the local authorities to identify additional witnesses we learned that most of the calls connected to the incident were in fact from members of the media, not eyewitnesses.

All the witnesses interviewed by the NY-SPI team were extremely credible, each one having spent many summers at the Jersey Shore. Every witness maintained a consistent story, describing what they saw, never attempting to jump to conclusions beyond the facts of the case. Most intriguing of all was the claim by the three teenagers (Anthony, Gregg, & Dallas) that they clearly overheard Coast Guard/police radio chatter on the beach that night reporting that wreckage HAD been recovered during the Coast Guard search. This is in direct conflict with the Coast Guard report that no evidence of a downed aircraft had been recovered during their search. Unfortunately, with no other sources to corroborate the teenagers' report, NY-SPI is unable to arrive at a definitive conclusion that wreckage (from some sort of crash) was located in the waters off Normandy Beach that night.

While some eyewitnesses (like Matt Sosnowski) described an object virtually identical to a fireball (sporadic meteor), we were unable to locate a single eyewitness reporting an exploding fireball, as was indicated in a variety of media sources.

Initially we were extremely interested in rumors of beaches closings in the days following the incident. NY-SPI obtained both print and television news report verification that beaches in the area of Normandy Beach were in fact closed in the days following the incident due to medical waste from an unknown source washing up on shore. While this seemed like an uncanny coincidence, we were never able to connect these unexpected closings (the beaches in this area have been relativley clean for a number of years). Outside of a conspiracy theory there is nothing definitive to tie the beach closing to this case. One possible explanation considered by the team was that a meteorite impacting the ocean floor had dislodged medical waste that had been deposited many years ago. As with much of this case, there is no evidence to support this theory.

NY-SPI team members spent an entire day searching the waters off the Jersey shore within the coordinates provided by the Coast Guard. While the search did not yield any evidence (either of a meteorite or aircraft wreckage), we knew it was a long shot with such a large area to search and the event having occurred several months earlier. But since the Coast Guard had only conducted a surface search, we had to take a chance.

In the end, the NY-SPI team felt we were dealing with several independent events. 1. One or more fireball meteors, which may or may not have exploded over the Jersey shore. 2. Some sort of aircraft (likely military related) crashing into the water off Normandy Beach. Again, there is limited evidence to support these findings so these are preliminary theories at best. We reserve the right to change our theories if and when new evidence emerges, as would any good scientist or investigator.

Most significant of all was the media influence on the development of this case. Here we have an excellent example of media distortion feeding upon itself and blowing a case into something much grander than it ever was in actuality. That being said, it was a fun case to investigate. I just wish we could have mobilized while it was still warm; the beaches were beautiful and inviting despite the frigid weather."

Dennis Anderson:

"I was not available to interview witnesses, therefore, my observations are strictly astronomical in nature. All descriptions of the event in my opinion, point to a fireball. The flight trajectory, the colors and appearance are consistent with a meteor of this type. The Aurigid meteor shower peaked that morning, and was most visible from the west coast. Meteors can usually be seen a day or two before and after a shower's peak. However, the direction of flight if reported correctly, would indicate the object seen was not related to the shower. I believe it was a sporadic meteor, which had no association with the shower. There is the possibility of an overlapping event having taken place that night, but I will leave that to other members of the NY-SPI team that investigated that part of the case."

Denise Petty:

"The Normandy Beach case is a perfect example of how, at first, many seemingly different testimonies, once pieced together, correlate to a cohesive event. When an event occurs, it is very rare that each witness views the event from exactly the same point of view. These differing points of view need to be analyzed to determine where each piece of the puzzle fits into the larger picture.

Case in point: Dallas and the other teenagers on the beach in Normandy Beach report a very different event than that which was viewed by Gail Steinbacker in Ortley Beach. What gave Dallas' testimony the heaviest weight was the corroboration by her father. This helped eliminate the attention-seeker equation seen many times when recall of events are presented. Her testimony did not change.

Further supporting this is USCG Petty Officer Sova's relation of the events. While I believe he was being honest based on my experience, I also have intimate knowledge of military training exercises used during basic training that allows a service-member to relate events and not give any body language or eye-movement cues. I believe that he related the facts as they were related to him. Yet I do not rule out the possibility that there is more information held by the military that was not divulged to the NY-SPI team. Repeated FOIA requests may yet yield additional information over time.

With all of the above taken into consideration, together with the various media reports, I believe that there was an event of consequence that occurred on that beach that night. I believe that no one knows exactly what happened, and I also believe that this investigation is not yet resolved."

Maps and Timeline

©ny-spi

Timeline:

8:30 PM - Captain Matt Sosnowski witnesses fireball flying from West to East.
8:35 PM - Teenagers see spiraling object thought to be a plane crash into the ocean.
8:45 PM - Chuck calls the police and is transferred to the Coast Guard.
8:49 PM - First call received by Coast Guard dispatch.
8:50 PM - Coast Guard "Defender Class" search boat leaves dock.
9:20 PM - Coast Guard search boat arrives at search location off Normandy Beach.
9:50 PM - Coast Guard helicopter arrives on site and initiates a 12-mile sweep.
10:30 PM - Radio and television newscasts report possible downed airplane.
10:35 PM - Gail Steinbacker sees bright-white lights over water from Ortley Beach.
11:30 PM - Search mission called off with no crash debris or fuel sheen found.

©ny-spi

A bird? A plane? A UFO? No, that was a meteor streaking the early morning sky

The Oregonian
Tue, 19 Feb 2008 10:40 EST

If you spotted bright lights streaking across the predawn sky this morning, you weren't alone.

And no, it wasn't a UFO. Turns out it was a meteor blazing across the sky about 5:30 a.m. Calls started pouring into the Federal Aviation Administration immediately, said a representative at the agency's Renton, Wash., operations center. He said air traffic control center operators confirmed it was a meteor.

The FAA representative said the agency got calls from early risers in Oregon, Washington and Idaho who wondered what it was they'd seen.

Got pictures or video of the meteor? Send it along to newsroom@news.oregonian.com.

Meteor seen across wide swath of Pacific Northwest

Associated Press
Tue, 19 Feb 2008 11:57 EST

SPOKANE - A meteor was seen across a wide area of the Pacific Northwest early today.

A Federal Aviation Administration duty officer in Seattle confirms that the streaking light in the sky was a meteor.

The officer, who would not give his name, told The Associated Press it was seen by pilots from Boise, Idaho, westward well into Washington state.

KHQ Television in Spokane has reported getting viewer calls from much of Eastern Washington and North Idaho.

Various callers to the station say it resembled summer lighting, a rocket, a satellite or an exploding transformer.

Effects of the large June 1975 meteoroid storm on Earth's ionosphere 

P. Kaufmann, V.L.R. Kuntz, N.M. Paes Leme, L.R. Piazza, J.W.S. Vilas Boas, K. Brecher and J. Crouchley
Science, Nov. 1989
Mon, 19 Nov 1990 07:10 EST

AN EXCEPTIONALLY LARGE METEORoid storm was detected on the moon by the Apollo seismic network between 20 to 30 June 1975, attaining daily impact rates five to ten times larger than the normal steady rates [1]. The storm has been interpreted as arising from a meteoroid cloud with a diameter of 0.1 astronomical unit and a total mass of [10.sup.13] to [10.sup.14.g.] Duennebier et al. [1] have estimated that a total mass of fragments of about 1.8 X [10.sup.6] g collided with the moon during the event.

To the best of our knowledge, however, no effects on Earth were reported as arising from this large event. Given the cross sections represented by Earth in comparison to the moon, a total meteoroid mass of about 2.4 X [10.sup.7] g should have impacted Earth during the 10-day period, which corresponds to an average of 2.4 x [10.sup.6] g/day. This is one order of magnitude larger than the most important regular Geminid meteoroid shower of about 1 X [10.sup.5] to 3 X [10.sup.5] g/day (0.1 to 0.3 ton/day) [2, 3]. These numbers, however, are likely to be larger for Earth because of its larger accretion effect [4].

The June 1975 storm was thought to be a very rare event because of its exceptional strength [1, 5]. The radiant direction was toward the sun. There is a suggestion that it could be an enhancement of the well-known [beta]-Taurid daytime shower [5]. Brecher [6] suggested that the June 1975 meteoroid storm was associated with the "Canterbury Swarm" as a result of the remains of an early Comet Encke fragmentation, which would also include the [alpha]-Taurid and [beta]-Taurid showers and two asteroids (2212 Hephestos and 1982 TA). According to Brecher [6], the close encounter of such fragments with the Earth-moon system might have produced some extraordinary events in the past, such as the 25 June 1178 flash on the moon, reported by a Canterbury monk, and the 30 June 1908 Tunguska event in Siberia.

The storm might also be the result of a more recent large fragmentation event in space. Such an event was suggested by Halliday [7], in order to explain the first observational detection of multiple meteorite falls from the same orbit (the Innisfree and Ridgedale meteorites, detected on 6 February 1977 and on 6 February 1980, respectively, almost at the same universal time (UT) and falling less than 500 km from each other).

We decided to inspect old data on very low frequency (VLF) propagation obtained in the period. Long-distance VLF transmissions propagate in an Earth-ionosphere spherical waveguide, according to well-known models [8, 9]. The VLF phase variations are directly related to changes in the height of the upper boundary of the waveguide, located in the low terrestrial ionosphere. The boundaries are set by a certain electron density. Nighttime height is typically 85 km at the ionosphere E region, whereas daytime height is 70 km at the D region. On the other hand, meteoroids are known to produce ionized trails as the result of conversion of the kinetic energy of the meteors into potential energy of ionization as the meteors are slowed down by collisions with gases in the upper atmosphere [10]. Observational results and model predictions, assuming a dustball structure for meteoroids, relate their masses to the heights where the trails are defined [11, 12]. For trails ending at 85 and 70 km, the meteoroid masses should be in the range of 0.1 to hundreds of grams, respectively (these figures should be considered as lower limits). Indeed, for the June 1975 storm, Duennebier et al. [1] estimated the density of the cloud, for an assumed distribution for the detected objects, and found that 18% of the mass in the observed range (50 g to 50 kg) was in the fraction with mass greater than 5 kg.

The effects of regular meteoroid showers in VLF transmissions have been known for some time [12, 15]. However, the showers are known to produce small 4 to 7 [delta] deviations in nighttime mean phase levels, which can be observed only in the absence of other anomalous propagation effects (caused by particle precipitation and high geomagnetic activity).

We searched for effects of the June 1975 event on the VLF propagation paths shown in Fig. 1. Data were available in strip charts and were reduced every 30 min. The transmissions received at Itapetinga Radio Observatory, Atibaia, Brazil, were from the radio transmitters Omega-Trinidad (at 10.2 and 13.6 kHz), Omega-Haiku, Oahu, Hawaii (10.2 kHz), and NAA, Cutler, Maine (17.8 kHz). Omega-Japan (10.2 and 13.6 kHz) transmissions were received at the University of Queensland, Brisbane, Australia. Propagation data from NLK (18.6 kHz), Jim Creek, Seattle, Washington, obtained at Nishinomiya, Japan, did not show any important anomaly in the period of interest [16]. NAA (17.8 kHz) signals received at Thule, Greenland, Exhibited a smooth change in diurnal phase variation, with a minimum signal late in June [17], a normal effect that may be attributed to a seasonal dependence, because that propagation path is under sunlight nearly all the time in the northern summer.

Limited by the observing schedules, the data gathered at Atibaia covered the period 17 to 30 June 1975, and the undisturbed days used for comparison were 17 and 18 June 1975. The data from Brisbane covered a larger period, 3 June to 15 July 1975, with the best undisturbed days 28 June to 13 July. The NAA data received at Atibaia were difficult to analyze and required daily adjustments, because of the phase jumps that occur when the two transmitting antennas are switched. Omega-Japan (13.6 kHz) and other VLF data received at Brisbane were quite noisy and difficult to analyze.

The VLF propagation anomalies, correlated in time with the June 1975 meteoroid storm, have been detected in four ways: (i) a daytime phase advance in the period; (ii) large anomalous nighttime phase advances (lasting a few hours on some days) particularly pronounced on Omega-Trinidad transmissions, where they attained amplitudes comparable to Lyman-[alpha] ionization during sunrise; (iii) a phase advance of the mean nighttime phase level and a reduction in the diurnal phase variation, which were partly caused by the important anomalies (ii); and (iv) a pronounced reduction in sunset phase delay time rates, at all transmissions, indicating the presence of an extra ionizing source. In 21 years of VLF observations in Brazil, we had not seen effects (i), (ii), and (iv) before.

The VLF phase behavior in the period of interest, for the shortest southern propagation path (Omega-Trinidad to Atibaia, Brazil), is shown in Fig. 2. We filtered the data, subtracted the normal diurnal phase variation, and used the mean readings from 17 and 18 June 1975 as typical. The most important anomalies are evident, such as the steady daytime phase advance of about 2.9 degrees/Mm (at 10.2 kHz; units are in degrees per megameter of propagation path) and 1.8 degrees/Mm (at 13.6 kHz) from 19 to 28 June 1975; the steady nighttime phase advance and large anomalies, which consequently contributed to the reduction in the mean diurnal phase variation.

These effects were also present in the other transmission, but to a lesser extent relative to the larger normal diurnal phase variations (because of the longer paths). The effects are more pronounced at the lower VLF frequency of 10.2 kHz (Fig. 2), a trend confirmed in all other transmissions analyzed in this study.

The large nighttime phase advances are particularly pronounced on 23 and 26 June 1975. They might be attributed to ionospheric disturbances produced in the daytime side of Earth, affecting the nighttime ionosphere as well through a number of mechanisms, such as traveling disturbances guided by E-region winds [10].

On the other hand, in Fig. 3 we show the daily deviations of the diurnal phase variations with respect to the mean in undisturbed days for all transmissions (in degrees per megameter of path length), compared to the meteoroid impact rates on the moon [1]. The correlation is rather remarkable, especially in the period 22 to 29 June 1975. The Brisbane data, however, suggest that the effects started several days earlier, becoming further enhanced on 20 to 26 June, disappearing afterwards. Similar plots are obtained for the other anomalies.

During the storm period, the sunset phase delay slowed with time became considerably smaller than the normal one in most of the transmissions. However, no anomaly was found in the sunrise phase advance slope with time. The sunset phase delay is the result of a combined effect of electron-ion recombination and the terminator movement along the propagation path. The phase delay time rate ([[phi].sub.D]) may be represented as approximately [[phi].sub.D] = [[phi].sub.N] - [[phi].sub.Nq] where [[phi].sub.N] is the normal rate of change of phase at sunset, which is the observed disturbed rate, and [[phi].sub.q] the change due to the production rate, q, of electrons attributed to the meteoroids. An order of magnitude of the rate of this production may be estimated assuming that in general any phase change is related to the well-known continuity equation ([phi] [alpha] (dn/dt) = q - [[alpha n.sup.2], where n is the electron density and [alpha] is the recombination coefficient). After some algebraic manipulations we obtained: [Mathematical Expression Omitted]

We plotted the difference between the mean value for undisturbed days (<[[phi].sub.N]>) and [[phi].sub.D] for each disturbed day (Fig. 4). These are given in units of degrees per megameter per hour. the typical <[[phi].sub.N]> was 5 (Omega-Haiku, 10.2 kHz), 8.3 (Omega-Trinidad, 10.2 kHz), 9.8 (Omega-Trinidad, 13.6 kHz), and 14 (NAA, 17.8 kHz) for the transmissions received in Brazil, and 4.6 (Omega-Japan, 10.2 kHz) for transmission received in Australia. We assumed that both [alpha] and n remained close to their typical values at an intermdiate daytime and nighttime low-ionosphere height [18], that is n [nearly equals] 6 X [10.sub.2] [cm.sup.-3], [alpha] = 4 X [10.sup.-6] [cm.sup.3] [s.sup.-1] at about 80 km. We then obtained an estimate of the electron production rate attributable to the meteoroid storm q [nearly equals] 0.3 to 0.9 [cm.sup.-3] [s.sup.-1] on the most disturbed days, which is three to nine times larger than estimates given for the large 1946 Giacobinid shower [2].

The unusual effect of daytime phase advance (Fig. 2) suggests that the long-lasting ionizing effects of the storm were so strong that they were able to modify significantly the daytime upper boundary of the Earth-ionosphere waveguide (that is the D region). We may also estimate the ion production rate to account for the daytime phase advance, using again the continuity equation and the Earth-ionosphere waveguide theory [8, 9]. Taking the daytime phase advances at the Omega-Trinidad transmissions received at Atibaia (Fig. 2), we infer a reflection height reduction of 1.5 km. Using a relationship for height reduction versus ion production rates, derived for solar flare x-ray effects [19], we estimate q [nearly equals] 3 [cm.sup.-3] [s.sup.-1] attributable to the storm, at an altitude of about 70 km.

Comparing the different VLF transmissions, the effects are considerably larger on the Trinidad-Atibaia path, which extends mostly in the Southern Hemisphere. This might indicate a directional property for the impacting stream of meteoroids. If we assume that the meteoroid storm effects were predominantly a Southern Hemisphere phenomena, we can tentatively reduce the anomalies for the corresponding southern sections of path lengths. The Omega-Trinidad, Omega-Haiku, and NAA paths to Atibaia are 60%, 50%, and 33% in the Southern Hemisphere, respectively. Omega-Japan to Brisbane path is 40% in the Southern Hemisphere. If we normalize the effects for the corresponding fractions of the paths, the magnitude of the effects (such as those shown in Figs. 3 and 4) are no longer so discrepant for the different transmissions. Similar results are found to the other two effects. It is also meaningful that the VLF propagation paths located entirely in high northern latitudes [Jim Creek to Nishinomiya and NAA to Thule (Fig. 1)] [16, 17] did not exhibit any anomaly in the period, except for smooth seasonal variations.

On the other hand, it was found that the meteoroid ionization effects remained during sunset hours, although they were not present at the sunrise phase advance period. The sunset effect was measured at the linear part of the phase delay with time, as the terminator moved from the receiver to the transmitter sites (Fig. 1). Depending on the transmission, the effect remained up to 1.5 to 3 hours after sunset at the receiver site. Therefore we suggest that the radiant right ascension was larger than the solar right ascension by about 1 to 2 hours. Since the sun's right ascension was about [90degrees], the suggested storm radiant was 105[degrees] to 120[degrees]. None of the well-known meteor showers are located in the Southern Hemisphere, at such right ascension [20], except, perhaps, the Corvids shower, which was observed only in 1937 (dec. = -10[degrees], right ascension = 191[degrees]). It is likely that the June 1975 event was caused by a genuine sporadic meteoroid storm.

Finally, the peak impact per day rate on the moon, detected on 23 June 1975, does correspond to a larger ionization effect on Earth's upper atmosphere (Figs. 2 and 3). However, the largest ionization effect on 26 June 1975, does not show a clear correspondence with impacts on the moon. Interpretations should be made carefully, since the effects on Earth's ionosphere are believed to be complex and largely smoothed out in time, compared to the direct detection of impacts on the moon. However, the lack of strict day to day correlations between data from Earth and moon suggest that the meteoroid stream was not homogeneous in space.

REFERENCES AND NOTES

[1] F. K. Duennebier, Y. Nakamura, G. V. Latham, H. J. Dorman, Science 192, 1000 (1976).

[2] J. S. Greenhow and A. C. Ratcliffe, Ed. (Academic Upper Atmosphere, A. J. Ratcliffe, Ed. (Academic Press, London, 1960), p. 513.

[3] D. W. Hughes, in Cosmic Dust, J. A. M. McDonnell, Ed. (Wiley, Chichester, United Kingdom, 1978), chap. 3, p. 123.

[4] L. W. Bandermann and S. F. Singer, Icarus 19, 108 (1973).

[5] J. Dorman, S. Evans, Y. Nakamura, G. V. Latham, Proc. Lunar Sci. Conf. 9, 3615 (1978).

[6] K. Brecher, A.A.S. (Am. Astron. Soc.) Bulletin 16, 476 (1984).

[7] I. Halliday, Icarus 69, 550 (1987).

[8] J. R. Wait, Proc. Inst. Radio Eng. 47, 998 (1959).

[9] J. R. Wait and K. P. Spies, National Bureau of Standards Tech. Note No. 300 (NBS, Boulder, CO, 1964).

[10] G. R. Sugar, Proc. IEEE 52, 116 (1964).

[11] R. L. Hawkes and J. Jones, Mon. Not. R. Astron. Soc. 173, 339 (1975).

[12] M. Beech, ibid. 211, 617 (1984).

[13] C. J. Chilton, J. Geophys. Res. 66, 379 (1961).

[14] G. C. Rumi, J. Atmos. Terr. Phys. 44, 733 (1982).

[15] J. W. S. Vilas Boas, N. M. Paes Leme, L. Rizzo, Piazza, S. M. M. S. Moura, ibid. 48, 643 (1986).

[16] Y. Muraoka, ibid. 41, 1031 (1979).

[17] J. E. Rasmussen, R. J. McLain, J. P. Turtle, W. I. Klemetti, U.S. Dept. of Army Rep. No. RADC-TR-76-270 (U.S. Army Air Development Center, Rome, NY, 1976).

[18] M. Nicolet, Astronautica Acta 11, 51 (1965).

[19] P. Kaufmann and M. H. Paes de Barros, Solar Phys. 9, 478 (1969).

[20] A. F. Cook, Evolutionary and Physical Properties of Meteoroids, C. L. Hemenway, P. M. Millman, A. F. Cook, Eds. (NASA Rep. SP-319, Washington, DC, 1973), p. 183.

[21] CRAAE is supported by the Universities of Sao Paulo, Mackenzie, Campinas, and the Institute of Space Research. This research was partially supported by Financiadora de Estudos e Projectos. One of the authors (V.L.R.K.) had a Coordenaqao de Aperfeicoamento de Pessoal de Nivel Superior fellowship.

P. Kaufmann, V. L. R. Kuntz, N. M. Paes Leme, L. R. Piazza, J. W. S. Vilas Boas, Centro de Radio-Astronomia e Aplicacoes Espaciais-CRAAE, Escola Politecnica, Universidade de Sao Paulo, C. P. 8174, 05508--Sao Paulo, Brazil.

K. Brecher, Department of Astronomy, Boston University, Boston, MA 02215.

J. Crouchley, Department of Physics, University of Queensland, St. Lucia, Queensland 4067, Australia.

Source Citation:Kaufmann, P., V.L.R. Kuntz, N.M. Paes Leme, L.R. Piazza, J.W.S. Vilas Boas, K. Brecher, and J. Crouchley. "Effects of the large June 1975 meteoroid storm on Earth's ionosphere." Science 246.n4931 (Nov 10, 1989): 787(4). Expanded Academic ASAP. Gale. Intercollege. 19 Feb. 2008

"Secret" extraterrestrial impacts revealed 

J. Kelly Beatty
Sky & Telescope, Feb 1994
Sat, 19 Feb 1994 07:00 EST

Astronomers have long stated that a large number of meteoroids frequently impact the Earth. Such incidents are rarely reported despite the enormous amount of energy released. However, newly-declassified documents show that secret military surveillance systems have been detecting such events.

Military satellites have been watching huge meteoroids slam into Earth's atmosphere for nearly two decades.

IN A CELEBRATED 1983 paper, Caltech planetary astronomer Eugene M. Shoemaker calculated that every year, on average, a fragment of asteroid or comet self-destructs somewhere in Earth's atmosphere with the kinetic-energy equivalent of 20,000 tons of TNT, or about |10.sup.24~ ergs. (The devastating Tunguska event in 1908, by comparison, delivered the equivalent of about 10 million tons of TNT.) Such large meteoroids would presumably be some 10 meters across, weigh upward of a thousand tons, and arrive at between 15 and 20 kilometers per second.

Fortunately, nonmetallic objects of this size are annihilated at altitudes too high to harm anything on the ground (S&T: March 1993, page 15). Still, no matter how high, a 20-kiloton explosion is not easily overlooked. It would, for example, eclipse the yield of the fission bomb that destroyed Hiroshima in 1945. Furthermore, in recent years the 36-inch Spacewatch telescope in Arizona has discovered numerous house-size objects hurtling through space very near the Earth. Based on these close calls, former Spacewatch team member David L. Rabinowitz (Carnegie Institution of Washington) concludes that Shoemaker's estimates of encounter rates were too conservative by 10 to 100 times. In the Astrophysical Journal for April 10, 1993, Rabinowitz counters that Earth should endure a 20-kiloton blast roughly every month and receive hundreds of kiloton-yield jolts annually.

Surprisingly, these cosmic cannonades are rarely reported -- only a handful are known from the last few decades. One was a dazzling, nighttime fireball over south-central British Columbia in March 1965, another a widely observed, daytime bolide that grazed Earth's atmosphere over the Rocky Mountains in August 1972. The sparse sightings hardly jibe with predictions of weekly events. So what's going on?

Much of the answer lies in an unprecedented body of spaceborne observations declassified and released in October by the U.S. Department of Defense. The report details a 17-year record of sightings made from orbit by satellites under the control of the U.S. Air Force Space Command. It will appear as a chapter in the book Hazards Due to Comets and Asteroids, to be published next year by the University of Arizona Press.

According to Edward Tagliaferri (ET Space Systems), the report's principal author, infrared scanners on military satellites have recorded a total of 136 atmospheric explosions since 1975, an average of eight probable meteoroids per year, each with an energy of roughly 1 kiloton or more. That's just the kind of observational input cosmic oddsmakers were hoping for. "I've been aware of this data for a long time," says Shoemaker, "and I've been waiting for the time when this could be released." Much of the credit for getting the once-secret database declassified goes to Simon P. Worden, a former astronomer who until recently headed a division of the Ballistic Missile Defense Organization (the "Star Wars" group).

Although the report neither discloses the identity of the surveillance system nor reveals details about its sensors, other sources suggest that the data have come from early-warning satellites of the Defense Support Program. Operating at the geosynchronous altitude of 38,000 km, the DSP sentinels use sophisticated detectors to monitor the Earth's upper atmosphere for rocket plumes and nuclear explosions. One type of sensor "stares" continuously at the entire disk. The high-altitude flashes it looks for are both brief and bright, making them detectable even in daylight against the slowly varying background of Earth lower down. If the airburst is vivid enough, a companion, visible-wavelength device then pinpoints its location.

Another sensor system uses arrays of supercooled detectors tuned to 2.78 microns, an infrared wavelength absorbed virtually completely by water vapor in the lower atmosphere. Married to large Schmidt optics with a 3.6-meter focal length, the array sweeps over Earth's infrared-dark disk every 10 seconds with enough sensitivity and spatial detail to pick up the hot exhaust of even modest ballistic missiles.

The new accounting is still well shy of the hundreds of comparably powerful annual events predicted by Rabinowitz. For example, the brightest flash recorded from orbit since 1965 probably resulted from a kinetic-energy yield of roughly 5 kilotons. One reason for the shortfall is that many airbursts go unreported, even though satellites detect them, because the systems and their handlers are watching for hostile activity and often either overlook or ignore natural events. Furthermore, the meteoric flashes last only a second or two, so on average the scanning infrared arrays miss at least four events for every one they glimpse. Allowing for such gaps, Tagliaferri estimates that at least 80 kiloton-yield meteoroids probably strike the Earth every year, a bombardment frequency higher than that derived by Shoemaker but still below the rate extrapolated from the Spacewatch discoveries.

Notably, of the 136 infrared events, only three turned up in records from the visible-light burst detectors, which have been flown since the early 1980s. Coincidentally, all three caught the attention of two satellites simultaneously. One occurred some 30 km above the western Pacific Ocean on October 1, 1990 -- a 2-kiloton blast right in the midst of the Kuwait-Iraq conflict. An observer on the ground below would have seen part of the sky briefly blaze like the Sun and would have heard a loud, low rumble soon thereafter. "Had this occurred over Kuwait it could have been a sticky situation," Worden observes. "We could tell it was natural, but they could not." Impact specialists hope the release of the previously classified records represents the first step in a long-term partnership with the surveillance community. They are pushing to have spacecraft collect such pivotal data more reliably and have it distributed openly. But Tagliaferri acknowledges that the existing systems have national-security objectives that simply cannot be compromised. One possibility, currently under negotiation, is to include comparable detectors on civilian satellites like those in the Global Positioning System.

Meteor researcher Douglas O. ReVelle (Los Alamos National Laboratory) notes that this is not the first time a defense-related system has yielded clues about the extraterrestrial infall rate. A global network of sensors operating between 1960 and 1974 (some from the rooftops of selected U.S. embassies) detected low-frequency acoustic waves from a handful of powerful airbursts that were probably meteoric in nature. One was believed to result from a small asteroid perhaps 20 meters across that fell harmlessly between South Africa and Antarctica on August 3, 1963 -- even though it packed the explosive punch of a half million tons of TNT!

With so many cosmic bombs bursting overhead one still has to wonder why there are so few visual reports of very bright bolides. Peter Brown, director of the International Meteor Organization for North America, offers at least two possible explanations. First, it may be that much more of the fireballs' energy is released in the infrared (where they're being detected) than at visible wavelengths (where they're not). Also, only in the last few years have fireball reports been collected on a systematic basis. In the future, he adds, the IMO and other meteor networks will be working more closely with their military counterparts to create a more complete record.

Meteorites - The uninvited guests 

Monica Grady
Geographical Magazine, March 1997
Sat, 01 Mar 1997 06:42 EST

Meteorites provide information about the formation of the Solar System. They are pieces of very old material that have fallen from space to the Earth. Most result from asteroid collisions in the Asteroid Belt between Mars and Jupiter, but over a dozen from the Moon and another 12 from Mars have also been identified. The three main types of meteorite are stone, iron, and stony-iron. Stony-iron meteorites are the rarest and are often quite beautiful. Antarctica is the best place to find meteorites because there the ice and aridity preserve them, sometimes for as long as a million years.

Each year approximately 40,000 tonnes of extraterrestrial material, most of it dust, bombards the earth. But where does it come from, and why does it land here?

Visitors from space arrive on the Earth with amazing frequency, not as alien monsters or little green people in flying saucers, but as meteorites, extraterrestrial material ranging from the tiniest of dust grains to enormous impact crater-forming bodies. Meteorites were formed at the birth of the Solar System, about 4,560 million years ago. We have no material on Earth this old, so it is only by studying meteorites that we can learn about the processes that shaped our Solar System and our planet.

Our Sun was born in a rotating cloud of gas and dust, called a nebula. Gradually this cloud collapsed and dust grained joined together to form bigger and bigger bodies, eventually producing the Sun and planets. The Sun is at the centre of the Solar System, and all the planets orbit around it.

The Asteroid Belt, the place from which most meteorites come, lies between Mars and Jupiter. Asteroids orbit the Sun at a distance three times that of the Earth from the Sun -- three Astronomical Units (AU), or 450 million kilometers. There are several thousand asteroids, the largest of which is about 1,000 kilometers across (the Earth has a diameter of about 13,000 kilometers). These rocky, metallic or carbon-rich bodies are the remaining after the planets formed; Jupiter's gravitational pull prevented them from joining together to form a single planet.

The asteroids are in stable orbits around the Sun, but occasionally, thanks to the influence of Jupiter, the orbit of an asteroid is altered so it collides with another and breaks up. Fragments of broken asteroid fall to Earth as meteorites.

We know that meteorites came from the Asteroid Belt as fireballs created by incoming meteoroids because they have been photographed. From their direction and speed, scientists can calculate the orbits of these meteoroids, and all are seen to extend out to the Asteroid Belt.

One of the most recent meteorite falls occurred on a Friday afternoon in October 1992. at Peekskill, New York.

©S. Eichmiller

S. Eichmiller's extraordinary photo of the Peekskill fireball of October 9, 1992

The track of the fireball was recorded on several video cameras, mostly by members of the public attending outdoor football games. The video footage has been edited together to produce a film of the fireball travelling over the northeastern U.S.

The meteorite eventually landed in the boot of a car.

©Pierre Thomas

The Peekskill meteor of 1992 was captured on 16 independent videos and then struck a car.

As well as meteorites from the Asteroid Belt, Earth has also received more than a dozen meteorites that have come from the surface of the Moon. Lunar meteorites have been compared directly with samples brought by the Apollo and Luna missions. The surface of the Moon is covered in the craters caused by impacting bodies. The force of these impacts is sometimes sufficient to throw material off its surface, and it is this that arrives on Earth. In the same way, rocks have come to us from Mars: scientist have identified 12 Martian meteorites.

The very bright fireball often associated with an incoming meteoroid is the result of frictional heating as the body travels through the atmosphere. Only the outermost surface melts; the resulting droplets of molten material are carried away by the speed of passage. Finally, as the molten surface rapidly cools to a glassy coating, or fusion crust, which helps scientist identify meteorites. The interior of a meteorite remains cool and unchanged, and meteorites are cold when they land.

©Swiss Meteorite Lab

The Peekskill Meteorite is composed of dense rock and has the size and mass of an extremely heavy bowling ball. If you are lucky enough to find a meteorite just after impact, do not pick it up -- parts of it are likely to be either very hot or very cold.

The very smallest of micrometeorites do not melt as they pass through the atmosphere, whereas those that are slightly larger melt and form tiny rounded droplets. Very large meteorites fall only every million years or so. Arizona's 1.2 kilometre-diameter, Meteor Crater, was produced by the impact of an iron meteorite about 50,000 years ago. The original meteorite weighted up to 25,000 tonnes, and would have been about 35 to 40 metres across, but most of it was vaporised by the impact. A really big meteorite, probably about 10 kilometres in diameter, fell at Chicxulub on the Gulf of Mexico about 65 million years ago. As well as forming a crater 200 to 300 kilometres across, the environment changes brought about the impact are thought by many scientist to have resulted in the extinction of the dinosaurs. Several smaller meteorites weighted about a kilogram fall on the Earth every year, but only five or six are seen to fall. The last one seen to fall in England was in May 1991, at Glatton, near Peterborough. This stony meteorite weights just over half a kilogram and fell through a hedge of conifers in the garden of a Mr Pettifor, who was started by the whining noise it made as it hurtled through the air.

Meteorites are pieces of ancient material that survive their fall to Earth from space. There are three main types of meteorite (stone, iron and stony-iron), reflecting their main composition. Meteorites are named after a place near where they fall or are found. Most meteorites (96 per cent of falls) are stony, made up of the same minerals as many terrestrial rocks, minerals containing silicon, oxygen, magnesium, iron and calcium. Stony meteorites can be sub-divided into those which have formed from melts of their parent bodies (like terrestrial igneous rocks), and those which have remained unchanged since formation, or aggregation. The latter are known as chondrites, after the small rounded droplets of once-molten material (chondrules) they contain.

Iron meteorites comprise, as their name implies, mainly iron metal, and generally contain between seven to 15 per cent of their weight in nickel. These meteorites have been formed during the melting of the parent bodies from which the meteorites originated.

The final main sub-division of meteorites is the stony-irons: a mix, as the name suggests, of stone and metal. These are very rare meteorites and beautiful in appearance. They are produced from the intergrowth of iron and magnesium silicate minerals with iron metal. Like iron meteorites, they were formed during the melting of their parents.

Different types of meteorites provide evidence about events that have occurred as the Solar System formed and evolved. Iron meteorites are the closest physical analogy we have to the material that forms the Earth's core. The stony meteorites represent material from the core/mantle boundary of their parent body.

The most primitive meteorites, the CI carbonaceous chondrites, are rich in water, sulphur and organic compounds. These might be the material remaining from comets, which are essentially a mixture of ice and dust, after all the ice has evaporated. It is material like this that brought volatiles to the newly-formed Earth, and helped established its atmosphere and oceans.

Several of the 12 Martian meteorites found on Earth contain pockets of glass formed during the shock event that ejected them from the surface of Mars. When this glass is melted in the laboratory, gas that was trapped inside the glass by the shock is released and compared with that analysed by the Viking space probes in 1976. The compositions are similar, although Martian meteorites also contain carbonate grains, produced below the surface of Mars when water circulated through the planet. A recent report by scientists from NASA has described evidence for fossilised martian bacteria inside these carbonate patches, showing that life might once have existed there. By studying meteorites like this, we can learn about events that have taken place in the past on our neighbouring planet, a planet whose surface now appears to be dry.

Meteoroids Hit Atmosphere In Atomic-Size Blasts 

William Broad
The New York Times
Tue, 25 Jan 1994 03:49 EST

Secret data from military satellites in orbit thousands of miles above Earth show that the planet is continually bombarded by big meteoroids that explode in blasts the size of atomic detonations. The data, from spacecraft meant to watch for rocket firings and nuclear explosions, were declassified recently by the Defense Department and are to appear later this year in a book.

From 1975 to 1992, the satellites detected 136 explosions high in the atmosphere, an average of eight a year. The blasts are calculated to have intensities roughly equal to 500 to 15,000 tons of high explosive, or the power of small atomic bombs. Experts who have analyzed the data are publishing it in the book, Hazards Due to Comets and Asteroids, say that the detection rate is probably low and that the actual bombardment rate might be 10 times higher, with 80 or so blasts occurring each year.

The disclosure of a new class of large meteoric impacts is seen as bolstering the idea that Earth is subjected to strikes from space in a wide range of severities, including an occasional doomsday rock perhaps once every 10 million years or so that causes mayhem and death on a planetary scale.

The new data are also being praised as a cold-war spinoff that can aid the cause of world peace by preventing false warnings of nuclear attack. Indeed, it turns out that Federal analysts on several occasions have struggled quietly for months to determine if such explosions were natural or manmade.

Finally, impact specialists hope the release of formerly secret data will be repeated and promote a new alliance between astronomers and the keepers of military reconnaissance.

"It's important," Dr. Eugene M. Shoemaker, an astronomer at the Lowell Observatory in Flagstaff, Ariz., who helped found the field of Earth-impact studies, said of the new data in an interview. "It's a unique source of scientific information."

Sky and Telescope magazine, based in Cambridge, Mass., which discusses the data in its February issue, lauded the once-secret sightings as "an unprecedented body of spaceborne observations."

Sighted for ages but understood in detail only recently, meteoroids are rubble left over from the creation of the solar system. They are composed of ice, rock, iron and nickel in a variety of shapes and sizes.

Meteor showers and individual streaks of light that flash across the sky every night are generated when tiny flecks of celestial detritus, often no larger than grains of sand or pebbles, burn up while speeding through the atmosphere.

In contrast, the blasts seen by the military satellites are produced when speeding objects up to the size of large houses are heated to incandescence and then explode about 17 to 20 miles above Earth. They create vast fireballs and powerful shock waves that nonetheless leave few or no discernible traces on the ground, since they begin so high up. If made of dense metal, meteoroids of this size have a good chance of punching through the atmosphere to hit the ground.

Scientists have suggested that once every 10 million years or so a truly colossal object from space cuts through the atmosphere and slams into Earth, sending up a global pall of dust that blots out the Sun, alters the climate and changes the course of evolution by killing off many plant and animal species. Such a menacing rock is thought to have carved out a 185-mile-wide crater 65 million years ago that now lies buried in the Yucatan Peninsula of Mexico. Its cataclysmic impact is believed by some scientists to have caused or assisted in the extinction of dinosaurs.

In general, the new observations are of a class of meteoroids too big to burn up harmlessly in the sky as shooting stars but too small to slice through Earth's atmosphere and strike the ground. They are middle children in the meteoroid family.

Previous Lack of Reporting

By definition, meteoroids are small bodies speeding through space that strike Earth's atmosphere. They can be comets made of ice or asteroids made of stone or metal. Meteors are streaks of light seen when meteoroids are heated while traveling through the atmosphere. Meteorites are the parts of relatively large meteoroids that survive passage through the atmosphere and fall to Earth as chunks of metal and stone.

The scientists who are publishing the new observations say the explosions of large meteoroids previously went largely unreported for many reasons. The vast majority occurred over the oceans or desolate parts of the continents. Many were obscured by clouds. And even when occurring in broad daylight and rivaling the Sun in brightness, the explosions lasted only a second or so, limiting the opportunities for observation.

"There's many more of these objects impacting the Earth than we previously thought," said Dr. Edward Tagliaferri, a physicist who was the lead author of the satellite report. "Their discovery is a fascinating story." Dr. Tagliaferri is a consultant for the Aerospace Corporation, a nonprofit engineering firm in El Segundo, Calif., that helps the Air Force run its numerous satellites.

The data were declassified by the Government last fall and are to be published this July or August as a chapter in the new book on meteoroid hazards, which is being published by the University of Arizona Press. The book grew out of four symposiums on meteoroid hazards and is being edited by Dr. Tom Gehrels, a planetary astronomer at the university who organized one of the meetings.

Dr. Gehrels heads a small team of astronomers who use a 36-inch telescope on Kitt Peak, west of Tucson, to search the sky for asteroids in orbit around the Sun that occasionally intersect Earth's orbit and one day might strike the planet. The effort is known as Spacewatch. Such research has so far identified a total of 185 potential interlopers. Generally these are larger than the objects that set off the satellite-observed explosions. Yet the mere existence of the big ones, and other clues like the heavy cratering on the Moon, have long implied that space is filled with swarms of smaller objects, which went largely unreported until now.

Findings Are Consistent

"It's a very interesting situation," Dr. Gehrels said in an interview. "Spacewatch is finding a certain number of objects in space that agrees with the things Tagliaferri is finding. The picture is consistent."

From such data, scientists have constructed a curve showing how often meteoroids of a given size might be expected to hit Earth. The curve predicted swarms of mid-size objects in about the numbers now being inferred from the military satellite records. The new data, in turn, support the validity of the curve that predicted them and increase confidence that the other end of the curve can help estimate the frequency of truly catastrophic events.

Dr. Clark R. Chapman, a senior scientist at the Planetary Science Institute, based in Tucson, cautioned that new disclosures and the raw data on which they are based had to be carefully analyzed before their soundness could be ascertained.

"I and most of my colleagues would like to see the data, not just the conclusions," he said. "So far it's more than we've seen before, but I'm not going to give it too much weight until I know more about it."

In the 20th century, the most celebrated collision between Earth and an object from space occurred in 1908 in the Tunguska region of Siberia. The object exploded in the atmosphere with a force of some 20 hydrogen bombs, its shock waves flattening hundreds of square miles of forest and registering on scientific instruments around the globe.

Reports of similar encounters over the decades have been rare. A near miss occurred in 1972 when a large asteroid, estimated at up to 260 feet in diameter, or nearly the length of a football field, sped through the upper atmosphere over the northern United States and Canada, blazing across the sky in a daylight fireball witnessed by thousands of people before it re-entered space.

Unknown to the public, military satellites in space for decades have been seeing large numbers of atmospheric blasts. The main witnesses have been early-warning craft known as D.S.P., for Defense Support Program, which perch in orbits some 23,300 miles above Earth, their telescopes searching the globe for signs of rocket attack. The sensors are said to mainly work in the infrared part of the electromagnetic spectrum, which is the domain in which heat is registered.

"D.S.P. has been seeing these for a long time and ignoring them," said Dr. Gregory H. Canavan, a physicist at the Los Alamos National Laboratory in New Mexico who works and publishes in the Earth-impact field.

Effort to Gather Data

The first effort to collect such data systematically began in 1975, Dr. Tagliaferri said. One motivation was to help the Defense Department distinguish between natural explosions and those caused by humans. The collection process was systematic but informal. Magnetic tapes on which raw data existed were usually recycled, so that the preservation of information depended largely on the skills and interests of individual Defense Support Program watch officers, who scanned the sky for trouble.

The importance of the analytical effort was driven home within the Pentagon bureaucracy in 1979, when a mysterious flash occurred over the Indian Ocean. Its geographical proximity to South Africa raised questions about whether it was a clandestine nuclear test, with the issue being hotly debated for years. Another flash near South Africa in December 1980 prompted another round of debate, with Pentagon analysts concluding two months later that the flash was evidently from a meteor.

The new report on the 136 atmospheric explosions is the first overview of this informational treasure trove. The report identifies no satellite system by name, but says at least two types were involved: an infrared system to search for rocket launchings, and a visible-light system to detect nuclear bursts. The former system is apparently operated by the Air Force and the latter one by the Energy Department.

The co-authors of chapter, in addition to Dr. Tagliaferri, are Dr. Richard Spalding and Dr. Cliff Jacobs of the Energy Department's Sandia National Laboratories in Albuquerque, N.M., Col. Simon P. Worden of the Air Force and Dr. Adam Erlich of Comprehensive Technologies International in Arlington, Va., a military contractor.

Colonel Worden, who also holds a doctorate in astronomy, is credited as being the main force behind the declassification of the secret data.

In an interview, Dr. Tagliaferri said the satellite systems, which he declined to name, were built and operated so they had about a 20 percent chance of seeing the one- or two-second flash of a meteoroid explosion anywhere around the globe. That uncertainty in trying to understand the overall rate of planetary bombardment was compounded, he said, by that fact that recording the data was usually an on-again, off-again affair.

Estimate on Incidents

"My sense is that there are about 10 times as many events" as were recorded, he said. "But there is no way to know."

He said calculations showed that the 136 blasts ranged from the equivalent of roughly 500 tons of high explosives up to 15,000 tons, the latter amountbeing the force of the nuclear bomb that leveled Hiroshima. The most accurately measured blasts were viewed by multiple satellite sensors. Of these, according to the book chapter, the brightest occurred on April 15, 1988, high above Indonesia. Its power was calculated to be equal to 5,000 tons of high explosives.

An observer on the ground 20 miles away would have seen a flash of light the brightness of the sun, the chapter says. Dr. Tagliaferri added that he knew of no reports of the explosion from Indonesia. It occurred at 11:20 A.M.

Another large explosion viewed by more than one satellite occurred on Oct. 1, 1990, over the Pacific Ocean and had a force larger than 1,000 tons of high explosives. A subsequent analysis concluded that the exploding object had been a stony, 100-ton asteroid.

"The Central Pacific asteroid detonation was originally collected as a potential nuclear event, and it took several months, using the most sophisticated sensors and algorithms available, to determine the detonation's true source," a manuscript of the book chapter states. "This suggests that developing nations and potential combatants worldwide, with considerably less sophisticated equipment, might potentially misidentify one of these detonations as a nuclear attack and 'retaliate' against the country's most likely aggressor."

In an interview, Dr. Tagliaferri noted that some widely reported events have been missed by the military satellites. On Oct. 9, 1992, for instance, a bright streak across the East Coast sky ended in Peekskill, N.Y., coming to Earth to slam through a 1980 red Chevrolet Malibu. The resulting hole went though the trunk and the gas tank. Found beneath the car was a smoking, football-size rock in a crater six inches deep.

"By accident," Dr. Tagliaferri said, "we didn't get anything on that."

SUV-Sized Asteroid Makes Surprise Pass Between the Earth & Moon 

Tavi Greiner
Slooh Skylog
Tue, 05 Feb 2008 12:26 EST

[On Tuesday, February 5], lost within the orange glow of the setting sun, a newly discovered asteroid passed within 84,000 miles of our planet, just a third of the distance to the Moon, and barely anyone noticed. A sharp-eyed skywatcher with a good pair of binoculars might have seen the unfamiliar object gliding silently through Aquarius. But did they know what they were seeing was a very unexpected asteroid? Would they have understood just how close it really was?

Near-Earth Object, 2008 CT1, was discovered only two days before [the] close pass by the Lincoln Near-Earth Asteroid Research project, an MIT project funded by the USAF and NASA committed to discovering space rocks that orbit near Earth. Using robotic telescopes located at New Mexico's White Sands Missile Range, the project has contributed nearly 70% of world-wide Near-Earth Asteroid discoveries since beginning operations in 1998.

[The] asteroid, estimated between 8m - 15m wide, sounds small as asteroids go, but recent studies suggest that even smaller rocks can be devastating. The cause of the Tunguska Event of the early 20th Century is now believed to be a 35m rock that never even touched the surface. The new hypothesis suggests it exploded a few miles above the ground, creating a shockwave that wreaked havoc on the ground beneath. Just last September, the Earth-impacting meteorite that created a 13m wide crater in Peru is estimated to have been just 0.2m - 2m wide.

[This most recent asteroid] pass was very close on a cosmic scale - and its late discovery makes it an even closer call. Asteroid 2007 TU24 got a lot of media attention last week, but we knew that one was coming and where to look. We even caught a glimpse on Slooh. With all the telescopes pointed to the heavens, watching the skies for that next great impactor, there are still rocks that slip by unnoticed. Observing close encounters with known asteroids is a great opportunity to learn more about our Solar System, and how to spot future Near Earth Objects - even those not on our radar yet.

Kidspace Children's Museum Displays Meteorite From 1570 

Caroline An
Wittier Daily News
Tue, 19 Feb 2008 12:08 EST

It hurtled through deep space and seared through the Earth's atmosphere, only to wind up as a child-friendly display.

A 379-pound nickel-iron meteorite made its debut this week at Kidspace Children's Museum, where it now occupies a prime spot in the museum's Boone Nature Exchange area.

The meteorite landed in Argentina and was discovered in 1570. It was donated to the museum by SuSan Nelson and Walter Witkowski.

It was unveiled Tuesday during a ceremony attended by local schoolchildren, community members, city officials and representatives from Caltech and Rep. Adam Schiff's office.

©Walt Mancini

Joseph Harrison, 4, of Pasadena looks at a 379-pound nickel-iron meteorite that has been added to the permanent collection in the Kidspace Children Museum's Boone Nature Exchange center. The meteorite landed in Argentina 10,000 years ago before being discovered by conquistadors in 1570. It belonged to a local private art collection in 2002 and was donated to Kidspace Children's Museum in Pasadena in 2008.

But its significance appeared lost to schoolchildren who viewed it Wednesday.

Many of them were decidedly unimpressed by the space relic. With its deep brown color and copper flecks, it looked like just another rock, several kids said.

"It's just a rock. If you turn it to this side, the profile looks like a turtle," said second-grader Roy Marquez, 8, of Jefferson Elementary School, who spent several minutes petting the meteorite.

And even though museum officials had placed the meteorite on an elevated platform, that wasn't enough to entice many students, who simply ran past it. Some students even jumped on the platform before sprinting off.

Punam Bhakta, a Kidspace off-site education lead, said the meteorite exhibit comes at the end of the tour of the Nature Exchange, which has plastic trays of different minerals, rocks and shells and tables to study.

"The kids play and then they slowly come up to it," Bhakta said.

Meteor streaks across Montana skies 

Mark Thorsell
KPAX
Tue, 19 Feb 2008 12:01 EST

The Associated Press is reporting that the meteor that streaked across Montana early Tuesday morning landed in eastern Washington.

A Federal Aviation Administration spokesman in Seattle says a Horizon Airlines pilot say the meteorite hit at around 6:45 a.m. near State Route 26 and Lind-Hatton Road in the southeast corner of Adams County. (click here for map)

There have been no reports of damage and sheriff's dispatchers say they aren't aware of any meteorite landing in the area.

Authorities say they have been inundated with calls from Kalispell, Plains, Missoula, Hot Springs, the Bitterroot Valley and Spokane, Washington of a bright light in the sky Tuesday morning. Callers described the phenomenon as bright blue in color.

Meanwhile, a Federal Aviation Administration duty officer in Seattle confirms that the streaking light in the sky was a meteor.

The officer, who would not give his name, told The Associated Press that it was seen by pilots from Boise, Idaho, westward well into Washington state.

Montana's News Station also received reports of a fire ball that lit up the sky in western Montana at around 6:30 a.m. on Tuesday.

Reports have come in from Victor to Ninemile and several people in the Blue Mountain area in Missoula have reported seeing the spectacle.

Viewers have called in to report seeing the sky light up from Ronan to between Billings and Livingston.

We talked with the National Weather Service office in Missoula and they tell us that nothing showed up on their radar Tuesday morning, but they received calls of the incident. They say from initial appearances it looks like a meteor crossed the area.

We'll have more on this story as information becomes available.

Meteor sighted in Clark County, region 

Justin Carinci
The Columbian
Tue, 19 Feb 2008 11:59 EST

Early risers across Clark County saw a meteor, described as blue or green in color, that hit the ground in Eastern Washington around 5:45 a.m. today.

The meteor was traveling from west to east, according to witness reports. The Associated Press reported the sighting was confirmed by the Federal Aviation Administration in the Seattle area, and was reported from Portland to Seattle and east to Spokane and Boise.

Travis Rood of Vancouver was driving east on McLoughlin Boulevard, around 5:25 a.m., on his way to work. He looked up as he approached Grand Boulevard and saw the meteor.

"It started out way high in the sky, like a basic shooting star," Rood said. "As it traveled eastward and downward, it just started getting bigger and bigger.

"It went from white to bright green to white," Rood said. "It looked like it hit in the east, and it lit up the whole sky like sheet lightning."

A Federal Aviation Administration spokesman in Seattle, Mike Fergus, says a Horizon Airlines pilot saw the meteorite hit earth about 5:45 a.m. Fergus says the pilot reported a flash and a burst of light near State Route 26 and the Lind-Hatton Road in the southeast corner of Adams County.

John Dingethal of Ridgefield described a brilliant flash of colored light on the eastern horizon at 5:30 a.m.. "I was looking out my second-story bedroom window and saw a round ball of intense blue light appear suddenly, like and exploding firework," Dingethal said.

In extreme northern Clark County, near Chelatchie Prairie, Cathy Potter reported seeing a blue-green ball of light with a small tail at the same time. She then described "an explosion of white, blue, green and orange similar to a transformer explosion."

Nothing As It Seems? Cylinder of Light and Great Explosion in Siberia 

Translated from Russian
As reported by RIA Novosti and other Russian News agencies
Sun, 17 Feb 2008 16:31 EST

Emergency crews of "Tyumen'TransGaz" removed consequences of the gust in the main gas pipe located in the Khanty Mansiysk autonomous area, as reported on Sunday by Emergency and Disaster Relief Ministry of the Russian Federation.

Comment: According to the words of the witness, there was a big explosion n Nyagan town in Siberia. The blow up was accompanied with a sound of "jet plane landing". He commented that the event was big.

©Borman from Leprosorium.ru

The gust of the main gas pipe occurred in the October region (northwest of the city Khanty Mansiysk) at 18.15 MSK on Saturday. There are no victims or injured, as mentioned in the report on the site of the Ministry.

©Borman from Leprosorium.ru

According to the data of the Ministry, gas workers overlapped the emergency section, and fire was liquidated at 19.16 MSK. There are no populated areas in the zone of emergency.

Comment: The above statement is perplexing, because you can clearly see that this event occurred near a populated area. Unless it was indeed very big and seen from afar.

©Borman from Leprosorium.ru

At present time gas is transferred to users on the backup gas pipe.

©Borman from Leprosorium.ru

Consequences of emergency are liquidated by "Tyumen'TransGaz" and Emergency and Disaster Relief Ministry teams of 24 people and 10 pieces of equipment.

©Borman from Leprosorium.ru

A similar emergency - the break of the main gas pipe with the subsequent fire occurred on Sunday morning in the suburb of Valdaya (Novgorod region). There are no injuries. According to the specialists of Emergency and Disaster Relief Ministry, possible reason for the incident is a deformation of the pipe with the so-called "fatigue of metals".

©Borman from Leprosorium.ru

©Borman from Leprosorium.ru

Meteor Over Portland Caught on Tape 

KPTV Oregon
Wed, 20 Feb 2008 09:56 EST

People across Oregon and southwest Washington spotted a fireball in the sky Tuesday morning.

Most reports of the fireball sighting came just after 5:30 a.m. A man who called 911 said "it lit up the whole sky" in the Milwaukie area.

FOX 12 meteorologist Drew Jackson said the object was likely the size of a basketball. He said that the object probably broke apart before hitting land.

©KOIN

Meteor over Portland

Video (courtesy KGW)
Video (courtesy CNN)

Jim Todd, the planetarium manager at OMSI, said some reports indicated hearing a sonic boom that rattled windows. He said the fireball moved from the west to the east.

Federal Aviation Administration officials in Portland said there were no reports of planes going down and they believe it may have been a meteor.

In the Portland area, there were reports of a bright flash of light being seen everywhere from Sauvie Island to Mount Tabor to Hillsboro.

Residents in the eastern Oregon cities of Baker City and Lagrande, and the southwest Washington cities of Woodland and Goldendale, also reported seeing the possible meteor.

Meanwhile, in Washington, a Federal Aviation Administration spokesman said a pilot reported seeing a burst of light in Adams County. Adams County sheriff's deputies and Washington State Patrol said there were no reports of an impact.

FOX 12 wants to hear from anyone who may have pictures, video or surveillance cameras that may have caught the fireball. Contact the FOX 12 newsroom by e-mailing FOX12news@kptv.com.

If you ever think you saw a meteor, you can report it via the American Meteor Society Web site.

Comment: Amazing the flash created by a "basketball" sized meteor. Imagine the blast made by something larger. Imagine the impact of several larger meteors arriving in close succession.....

What was that fireball that lit up the sky? 

AM 860 KPAM
portlandtribune.com
Tue, 19 Feb 2008 22:30 EST

Bright flash spotted at about 5:30 a.m. as far west as Tillamook, as far east as Idaho

A bright white streak in the sky early Tuesday was seen all across the Portland area, triggering dozens of calls to local 9-1-1 dispatchers.

It was most likely a meteorite.

The white flash was seen in the eastern sky, streaking from north to south around 5:30 a.m.

Dick Pugh, scientist with Cascadia Meteorite Lab at Portland State University, tells KPAM 860 radio it was probably "a fireball containing pieces of rock material coming into the atmosphere from space exploding at the end."

Pugh says meteorites, which travel 50,000 miles an hour, usually light up the sky around 90 miles above earth.

At Portland International Airport, air traffic controllers reported seeing a flash reflected in their windows.

Puge says if someone heard a sonic boom, it would indicate some meteorite pieces actually landed. So far, there have been no reports of falling pieces.

Anyone who saw or heard the meteorite should call Pugh, 503-287-6733.

Meteorites from Mercury? 

Ken Croswell
Sky and Telescope
Fri, 22 Feb 2008 14:20 EST

Meteorites from the Moon and Mars give earthbound scientists free rock samples from other worlds. Now Brett Gladman and Jaime Coffey (University of British Columbia, Vancouver) say we should expect a few meteorites from Mercury too.

Gladman and Coffey conducted computer simulations of what happens after asteroids and comets slam into the innermost planet and kick debris into space. Past studies assumed that rocks knocked off Mercury weren't getting away with much more than its escape velocity of 2.6 miles (4.2 km) per second. That's too slow to climb away from the Sun and make it out to Earth.

©NASA / JHU-APL / Carnegie Inst. of Washington

Taken by Messenger on January 14, 2008, from about 17,000 miles away, this view of a gibbous Mercury shows about half of the area not photographed by Mariner 10 in 1974 - 75. The heavily cratered landscape is reminiscent of other areas previously seen. The broad circular plain toward upper right, appearing brighter than its surroundings in this red-light view, marks the interior of Caloris basin, a huge impact scar more than 800 miles across.

But some previous assumptions were wrong, says Gladman, because the collisional circumstances at Mercury are "very different than anywhere else." The Sun's innermost planet speeds through space with a mean velocity of 30 miles (48 km) per second. Furthermore, asteroids and comets crossing Mercury's orbit also travel fast. So impactors strike the planet at speeds 5 to 15 times its escape velocity, and ejecta can rocket off the surface traveling much faster than had been assumed.

The new study, which has been submitted to Meteoritics and Planetary Science, concludes that up to 5% of this high-speed debris from Mercury reaches Earth - a third to a half of the delivery rate of meteorites from Mars. Gladman notes that roughly a half dozen samples of Mercury might already be sitting in meteorite collections worldwide.

But how would an interplanetary prospector recognize that a stone really is from the innermost planet? Some planetary geologists think a rare class of meteorites called angrites might be good candidates, though others disagree. Gladman cautions, "Until you have some kind of ground truth, it's very difficult to make those claims." He says scientists need more information about the composition of Mercury's surface to find matches with suspicious meteorites.

©Greg Hupé / The Hupé Collection

Rocks from Mercury? These pieces of the meteorite known as Northwest Africa 2999 are angrites, a rare type that some specialists believe may represent samples of Mercury's surface. The total weight of these is 392 grams (about 14 ounces); the small cube is 1 cm on a side.

Fortunately, the Messenger spacecraft has begun exploring the planet. Messenger flew past Mercury in January and will go into orbit in 2011. It should provide the data that will confirm or refute candidate meteorites from Mercury.

Ken Croswell is the author of Ten Worlds: Everything That Orbits the Sun (Boyds Mills Press, 2006).

An Elegant Proposal for Near Earth Asteroid Deflection 

Nancy Atkinson
Universe Today
Fri, 22 Feb 2008 22:20 EST

Although the chances of an asteroid hitting Earth appear to be small for any given year, the consequences of such an event would be monumental. The science community has come up with some ideas and proposals for ways to mitigate the threat of an incoming asteroid hitting the Earth. Some proposals suggest almost Hollywood type theatrics of launching nuclear weapons to destroy the asteroid, or slamming a spacecraft into a Near Earth Object to blow it apart. But other ideas employ more simple and elegant propositions to merely alter the trajectory of the space rock. One such plan uses a two-piece solar sail called a solar photon thruster that draws on solar energy and resources from the asteroid itself.

Physicist Gregory Matloff has been working with NASA's Marshall Spaceflight Center to study the two-sail solar photon thruster which uses concentrated solar energy. One of the sails, a large parabolic collector sail would constantly face the sun and direct reflected sunlight onto a smaller, moveable second thruster sail that would beam concentrated sunlight against the surface of an asteroid. In theory, the beam would vaporize an area on the surface to create a "jet" of materials that would serve as a propulsion system to alter the trajectory of the Near Earth Object (NEO.)

Changing the trajectory of a NEO exploits the fact that both the Earth and the impactor are in orbit. An impact occurs when both reach the same point in space at the same time. Since the Earth is approximately 12,750 km in diameter and moves at about 30 km per second in its orbit, it travels a distance of one planetary diameter in about seven minutes. The course of the object would be altered, or either delayed or advanced and cause it to miss the Earth.

But of course, the arrival time of the impactor must be known very accurately in order to forecast the impact at all, and to determine how to affect its velocity.

Additionally, the solar photon thruster's performance would vary depending on the unique makeup of each NEO. For example, asteroids with a greater density, radius or rate of rotation would cause decreased performance of the solar photon thruster in acceleration and deflection.

Even though the solar photon thruster appears to be efficient in its performance, Matloff said that more than half of the solar energy delivered to the "hotspot" on the NEO would not be available to vaporize and accelerate the jet due to other thermodynamic processes such as conduction, convection, and radiation. As expected, a larger collector sail radius would increase the amount of energy available, and would increase acceleration of the NEO. Matloff said this system allows the sail craft to "tack" against the solar-photon breeze at a larger angle than conventional single solar sails can achieve.

This system of sails would not be attached to the NEO, but would be kept nearby the NEO "on station" either with its own thrusting capability or by auxiliary electric propulsion. More studies would be needed to ascertain if a supplementary propulsion system would be necessary.

The sails used in the study were both inflatable. However, Matloff believes it might be worth considering a small rigid thruster sail, which might simplify deployment and reduce occultation.

Said Matloff, "Hopefully, future design studies will resolve these uncertainties before application of NEO-diversion technology becomes necessary."

First near-Earth triple asteroid discovered

Astonomy Report
Tue, 19 Feb 2008 13:16 EST

Once considered just your average single asteroid, 2001 SN263 has now been revealed as the first near-Earth triple asteroid ever found. The asteroid -- with three bodies orbiting each other -- was discovered this week by astronomers using the radar telescope at the National Science Foundation's (NSF) Arecibo Observatory in Puerto Rico.

©Arecibo Observatory

2001 SN263 has now been revealed as the first near-Earth triple asteroid ever found. -

Cornell and Arecibo astronomer Michael C. Nolan said he and his colleagues made the discovery when they obtained radar images Feb. 11. The group subsequently took more images to learn that the three objects -- about 7 million miles from Earth -- are rotating around each other.

The main, central body is spherical with a diameter of roughly 1.5 miles (2 kilometers), while the larger of the two moons is about half that size. The smallest object is about 1,000 feet across, or about the size of the Arecibo telescope.

Other triple asteroids exist in the asteroid belt (between Mars and Jupiter) and beyond, but this is the first near-Earth system where the actual shapes of objects can be clearly seen.

The Arecibo telescope is operated for the NSF by Cornell's National Astronomy and Ionosphere Center.

"This discovery has extremely important implications for ideas about the origins of near-Earth asteroids and the processes responsible for their physical properties," said Nolan. "Double, or binary, asteroid systems are known to be fairly common: about one in six near-Earth asteroids is a binary, but this is the first near-Earth triple system to be discovered."

The triple asteroid was first discovered visually Sept. 19, 2001, by the Lincoln Near Earth Asteroid Research (LINEAR) project, part of the Massachusetts Institute of Technology's Lincoln Laboratory. The orbits of binary-- and now triple -- asteroid systems unveil the mass and allow astronomers to assess whether they are stable over millennia or have formed very recently. Previous radar investigations of binary near-Earth asteroids have disclosed extraordinary physical and dynamical characteristics.

Nolan said this discovery prompts several important questions: Are the objects orbiting in the same plane? How rapidly are the orbits changing with time? Did the moons form when this asteroid formed in the main asteroid belt, or after it arrived in near-Earth space?

Because of the small sizes and irregularly shaped components, 2001 SN263 should offer unique insights relative to the much larger triple systems in the main asteroid belt, said Nolan. "Examining the orbits of the moons as we continue to observe 2001 SN263 over the next few weeks may allow us to determine the density of the asteroid and type of material from which it is made," he said. "We will also be studying its shape, surface features and regolith [blanketing material] properties."

Radar observations by the Arecibo Observatory can image a much larger fraction of the population of near-Earth asteroids than spacecraft. For example, Arecibo has discovered more than half of the near-Earth binary asteroid systems discovered since 1999. Continued observations will undoubtedly lead to the discovery of new classes of objects, such as this triple system. While the Arecibo telescope is capable of these investigations, the future of the radar program and the entire telescope are in considerable doubt due to NSF budget cuts.

Nolan's collaborators on the project are Ellen S. Howell, Arecibo Observatory/Cornell University; Lance A.M. Benner, Steven J. Ostro and Jon D. Giorgini, Jet Propulsion Laboratory/California Institute of Technology; Michael W. Busch, Caltech; Lynn M. Carter and Ross F. Anderson, Smithsonian Institution; Chris Magri, University of Maine at Farmington; Donald B. Campbell and Jean-Luc Margot, Cornell; Ronald J. Vervack Jr., Johns Hopkins University Applied Physics Laboratory; and Michael K. Shepard, Bloomsburg University.

Note: This story has been adapted from a news release issued by Cornell Univeristy

Ice "meteor" nearly killed our kids 

Tony Collins
Birmingham Mail
Sat, 23 Feb 2008 10:58 EST

TEACHERS and pupils at a Birmingham school will this week be analysing fragments of "meteor" ice which crashed into a playing field, narrowly missing stunned pupils.

It ploughed into the field at Yardleys Secondary School, in Tyseley, yesterday.

The ice is believed to be a megacryo-meteor - the name given to abnormally large chunks of ice which fall from a clear sky.

Pieces of the ice have now been stored in a freezer at the specialist science college in Reddings Lane for possible further analysis.

Yardleys community co-ordinator John Roden, the school's former head of science, said the block of ice was reddish in colour with no obvious odour.
He said: "This thing literally fell out of the sky and landed on the playing fields, narrowly missing a group of children who were going out to a games lesson.

"The kids thought it was a comet and it flew through the sky before hitting the ground near them.

"It shattered into several large chunks which we have stuck in the freezer.
"It was bigger than a shoebox and has left a sizeable hole in the ground. Without doubt, it would have killed anyone it landed on."

Schoolgirl Saisaa Akhtarckd, aged 12, was on the playing fields when it landed.
She said: "I saw it coming from over the factory next door.

"It was coming down from the sky really fast and melting at the same time, and the droplets were going backwards.

"It just missed us by a few yards. I thought it was a cake because of all the colours - pink, golden brown and strawberry, but when we went to see, we could tell it was ice."

Mr Roden said they contacted various agencies to report the incident, including the Environment Agency and the Civil Aviation Authority, in case it came from an airplane flying overhead.

"I have been trying to phone up people to check where it came from, but no one seems to know. It's just like having a science lesson in our own backyard."

Meteor Clue To End Of Middle East Civilisations

By Robert Matthews, Science Correspondent
UK Telegraph
Sat, 03 Nov 2001 08:45 EST

SCIENTISTS have found the first evidence that a devastating meteor impact in the Middle East might have triggered the mysterious collapse of civilisations more than 4,000 years ago.

©Unknown

satellite images of southern Iraq have revealed a two-mile-wide impact crater caused by a meteor

Studies of satellite images of southern Iraq have revealed a two-mile-wide circular depression which scientists say bears all the hallmarks of an impact crater. If confirmed, it would point to the Middle East being struck by a meteor with the violence equivalent to hundreds of nuclear bombs.

Today's crater lies on what would have been shallow sea 4,000 years ago, and any impact would have caused devastating fires and flooding.

The catastrophic effect of these could explain the mystery of why so many early cultures went into sudden decline around 2300 BC.

They include the demise of the Akkad culture of central Iraq, with its mysterious semi-mythological emperor Sargon; the end of the fifth dynasty of Egypt's Old Kingdom, following the building of the Great Pyramids and the sudden disappearance of hundreds of early settlements in the Holy Land.

Until now, archaeologists have put forward a host of separate explanations for these events, from local wars to environmental changes. Recently, some astronomers have suggested that meteor impacts could explain such historical mysteries.

The crater's faint outline was found by Dr Sharad Master, a geologist at the University of Witwatersrand, Johannesburg, on satellite images of the Al 'Amarah region, about 10 miles north-west of the confluence of the Tigris and Euphrates and home of the Marsh Arabs.

"It was a purely accidental discovery," Dr Master told The Telegraph last week. "I was reading a magazine article about the canal-building projects of Saddam Hussein, and there was a photograph showing lots of formations - one of which was very, very circular."

Detailed analysis of other satellite images taken since the mid-1980s showed that for many years the crater contained a small lake.

The draining of the region, as part of Saddam's campaign against the Marsh Arabs, has since caused the lake to recede, revealing a ring-like ridge inside the larger bowl-like depression - a classic feature of meteor impact craters.

The crater also appears to be, in geological terms, very recent. Dr Master said: "The sediments in this region are very young, so whatever caused the crater-like structure, it must have happened within the past 6,000 years."

Reporting his finding in the latest issue of the journal Meteoritics & Planetary Science, Dr Master suggests that a recent meteor impact is the most plausible explanation for the structure.

A survey of the crater itself could reveal tell-tale melted rock. "If we could find fragments of impact glass, we could date them using radioactive dating techniques," he said.

A date of around 2300 BC for the impact may also cast new light on the legend of Gilgamesh, dating from the same period. The legend talks of "the Seven Judges of Hell", who raised their torches, lighting the land with flame, and a storm that turned day into night, "smashed the land like a cup", and flooded the area.

The discovery of the crater has sparked great interest among scientists.

Dr Benny Peiser, who lectures on the effects of meteor impacts at John Moores University, Liverpool, said it was one of the most significant discoveries in recent years and would corroborate research he and others have done.

He said that craters recently found in Argentina date from around the same period - suggesting that the Earth may have been hit by a shower of large meteors at about the same time.

Flashback: Acid rain worries residents in Kaushambi 

ANI
Fri, 01 Feb 2008 09:58 EST

Residents of Uttar Pradesh's Kaushambi District are a worried lot as the area has been receiving acid rain for the past few days.

Residents of Uttar Pradesh's Kaushambi District are a worried lot as the area has been receiving acid rain for the past few days.

The stinking yellow coloured rain, reportedly each drop having half a centimeter diameter, has been giving nightmares to the residents of the area.

They say that the yellow rain has been falling mostly during the night though sometimes it falls during the daytime as well.

"For the past few days, we have been receiving yellow rain. We received more yellow rain in the night as compared to the day time although we saw yellow rain in the day as well. I have never seen anything like this in my life. Everybody is afraid," said Pushapa Manauri, a resident.

The yellow rain has been continuing for the past one-month. Experts say the yellow rain is actually acid rain.

"Chemicals get mixed with the moisture in the air by a chemical process and become acidic. This acid in the air gets mixed with dewdrops and falls on the ground. This is called acid rain. Since it is yellow in colour, it is called yellow rain. This acid rain has many unfavourable consequences," said S.S Ojha, Professor, Allahabad University.

This yellow coloured rain was first received in Kaushambi last year during the summer season.

Since then, it has become a cause of concern for the people who are worried about the unfavourable consequences of this rain.

Asteroids

National Space Society
Mon, 25 Feb 2008 16:33 EST

On 23 March 1989, asteroid 1989FC (with the potential impact energy of over 1000 megatons, roughly the equivalent a thousand of the most powerful nuclear bombs) missed Earth by about six hours [Freedman 1995]. We first saw this fellow after closest approach. If 1989FC had come in six hours later most of us would have been killed with zero warning.

There are two things you need to know about asteroids:

* Asteroids can make us extinct (the threat).
* Asteroids can make us rich and provide homes for trillions of people (the promise).

The Promise

There are vast numbers of asteroids in near-Earth orbits, some of which are easier to access than the Moon. The potential mineral wealth of these asteroids is so great that huge profits could be made once we can start mining them for materials to be sold to markets on Earth. Like space solar power, this is one of the potential revenue sources for the large startup costs for the first space settlements.

Asteroids can also be an enormous boon to orbital settlements. Orbital settlements must import their materials from either the Moon or asteroids. Diverting a few small (30-70 meter diameter) asteroids into Earth orbit could supply all the materials needed for early orbital settlement development.

While early orbital settlements may well be in Earth orbit, eventually humanity will spread out across the solar system. Then asteroids become prime targets for new settlements. Hollowing out a large, solid asteroid and building homes inside has great appeal. Such a settlement will have ample materials in the form of the asteroid itself, and the large mass of the asteroid provides immediate and substantial radiation protection. With a little care radiation levels could be less than on Earth.

Settlement of a large asteroid could start with a relatively small tunnel, providing a home for workers that could be gradually extended over time to build large open spaces and wonderful living areas with a complex geometry, providing endless, safe exploration possibilities for the children.

While some asteroids are believed to be solid enough to be hollowed out for living space, others are known to be 'rubble-piles,' barely held together by their weak gravity. While such asteroids cannot be hollowed out for living in, they are much easier to mine to provide materials for large numbers of orbital settlements.

The vast material resources of the asteroid belt beyond Mars may eventually provide home for the bulk of humanity.

The Threat

If we don't do something, sooner or later Earth will be hit by an asteroid large enough to kill all or most of us. That includes the plants and animals, not just people. Maybe this won't happen for millions of years. Maybe in 15 minutes. We don't know.

We have been warned. On 23 March 1989, asteroid 1989FC (with the potential impact energy of over 1000 megatons, roughly the equivalent a thousand of the most powerful nuclear bombs) missed Earth by about six hours [Freedman 1995]. We first saw this fellow after closest approach. If 1989FC had come in six hours later most of us would have been killed with zero warning.

We are hit by thousands of smaller asteroids every year and we don't see any of them before the collision.

In October of 1990 a very small asteroid struck the Pacific Ocean with a blast about the size of the first atomic bomb (the one that leveled Hiroshima, Japan, killing roughly 200,000 people in seconds). If this asteroid had arrived ten hours later it would have struck in the middle of more than a million U.S. and Iraqi soldiers preparing for war. How would America have reacted to what looked like an Iraqi nuclear attack? Hiroshima-sized explosions due to asteroids actually occur in the Earth's atmosphere about once a month [Lewis 1996b], but are seldom seen because most of the Earth is unpopulated. The data comes from Air Force satellites designed to look for nuclear explosions.

In 1908 a small asteroid (perhaps 50 meters across) hit Tunguska, Siberia and flattened 60 million trees. That asteroid was so small it never even hit the ground, just exploded in mid-air. If it had arrived four hours and fifty-two minutes later it could have hit St. Petersburg [Lewis 1996b]. At the time St. Petersburg was the capital of Russia with a population of a few hundred thousand. The city would have ceased to exist. As it was, dust from the blast lit up the skies of Europe for days. Asteroid strikes this size probably happen about once every hundred years. However, this is just an average. Just because we got hit once doesn't mean we're safe for another hundred years. Indeed, there was another Tunguska-class strike in the Brazilian rain forest on 13 August 1930 [Lewis 1996b].

There are about 1,000 asteroids a kilometer or more in diameter that cross Earth's orbit (the path Earth takes around the Sun). About a third of these will eventually hit Earth [Lewis 1996a]. An asteroid strike this large can be reasonably expected to kill a billion people or so, depending on where it hits. A strike in China or India would kill more, in Antarctica less. Even a strike in the ocean would create a tsunami so enormous most people living near the coast would be drowned. A strike of this size is expected about once every 300,000 years or so.

It's not just Earth. In 1178 our Moon was hit by an asteroid creating a 120,000 megaton explosion (about six times the force of Earth's entire atomic arsenal). The collision dug a 20 km (12 mile) crater. This strike was recorded by a monk in Canterbury, England. We are extremely lucky it didn't hit us. The Moon is a smaller target and has much less gravity to attract an impactor. If a 120,000 megaton blast had hit the Earth our history would have been dramatically different. We're just lucky that one hit the Moon instead.

The most recent large strike also missed Earth. In July 1994 the comet Shoemaker-Levy 9 plowed into Jupiter. The comet broke up into roughly 20 large pieces before contact, but when the pieces hit they left a string of enormous explosions clearly visible to our telescopes. The scale of the destruction was staggering. Each impact was the equivalent of about 10 million megatons of TNT.

Sixty-five million years ago a huge asteroid several kilometers across slammed into the Yucatan Peninsula in Mexico. This is the event that caused the extinction of the dinosaurs (and many other species). The explosion was the equivalent of about 200 million megatons of dynamite, about the equivalent of all 20 pieces of Shoemaker-Levy. The blast turned the air around it into plasma - a material so hot electrons are ripped from the atomic nucleus and molecules cannot exist. This is the stuff the Sun is made of. Enormous quantities of red-hot materials were thrown into space, most of which rained down worldwide burning literally the entire planet to a crisp. Anything not underground or underwater was killed. This scenario has been repeated over and over, perhaps once every 100 million years or so. Each collision killed up to 95% of all species on Earth. As many as two-thirds of all species that ever existed may have been terminated by asteroids hitting the Earth.

We know about the asteroid that killed the dinosaurs because we found the crater. But what happens when an asteroid hits the ocean? After all, oceans cover two-thirds of the Earth's surface, and most asteroid strikes are in water. Unless the asteroid is very large there won't be a crater. However, if you drop a rock into a lake it makes waves. The larger the rock the bigger the wave. Drop a 400 meter (four football fields) diameter asteroid into the Atlantic Ocean and you get a tsunami 60 meters (yards) high [Willoughby and McGuire 1995].

The only way to eliminate the threat of asteroids is to detect them and divert them. Right now we depend on a trickle of government funding for this. Detection of Earth-threatening rocks is very far from complete. At the present rate it will take years before we find just 90% of them.

A vigorous space settlement civilization based on asteroidal materials would have enormous economic incentives to find and utilize every asteroid passing anywhere near Earth. They would be found, diverted, and mined for their materials. This would defuse the threat, make an awful lot of people extremely rich, and provide lovely homes to even more people.

What a deal.

References

[Freedman 1995] George Friedman, "The Increasing Recognition of Near-Earth-Objects (NEOs)," Space Manufacturing 10: Pathways to the High Frontier, Proceedings of the Twelfth SSI-Princeton Conference, 4-7 May 1995, edited by Barbara Faughnan, American Institute of Aeronautics and Astronautics (AIAA), pages 157-164.

[Lewis 1996a] J. S. Lewis, Mining the Sky: Untold Riches from the Asteroids, Comets, and Planets, Helix Books, Addison-Wesley Publishing Company, Inc. [Review] [Buy from Amazon]

[Lewis 1996b] J. S. Lewis, Rain of Iron and Ice: The Very Real Threat of Comet and Asteroid Bombardment, Helix Books, Addison-Wesley Publishing Company, Inc. [Buy from Amazon]

[Willoughby and McGuire 1995] Allan J. Willoughby and Melissa L. McGuire (1995), "Adroitly Avoiding Asteroids! Clobber, Coax or Consume?" Space Manufacturing 10: Pathways to the High Frontier, Proceedings of the Twelfth SSI-Princeton Conference, 4-7 May 1995, edited by Barbara Faughnan, American Institute of Aeronautics and Astronautics (AIAA), pages 103-113.

Cosmic Dust Dumping? Dust in West up 500 percent in past 2 centuries, says CU-Boulder study 

University of Colorado at Boulder
Sun, 24 Feb 2008 17:11 EST

The West has become 500 percent dustier in the past two centuries due to westward U.S. expansion and accompanying human activity beginning in the 1800s, according to a new study led by the University of Colorado at Boulder.

Sediment records from dust blown into alpine lakes in southwest Colorado's San Juan Mountains over millennia indicates the sharp rise in dust deposits coincided with railroad, ranching and livestock activity in the middle of the last century, said geological sciences Assistant Professor Jason Neff, lead author on the study. The results have implications ranging from ecosystem alteration to human health, he said.

"From about 1860 to 1900, the dust deposition rates shot up so high that we initially thought there was a mistake in our data," said Neff. "But the evidence clearly shows the western U.S. had it's own Dust Bowl beginning in the 1800s when the railroads went in and cattle and sheep were introduced into the rangelands."

A paper on the research funded by the Andrew W. Mellon Foundation was published in the Feb. 24 issue of Nature Geoscience. Co-authors included CU-Boulder's Ashley Ballantyne, Lang Farmer and Corey Lawrence, Cornell University's Natalie Mahowald, the University of Arizona's Jessica Conroy and Jonathan Overpeck, Christopher Landry of the Center of Snow and Avalanche Studies in Silverton, Colo., the University of Utah's Tom Painter and the U.S. Geological Survey's Richard Reynolds.

The study indicates "dust fall" in the West over the past century was five to seven times heavier than at any time in the previous 5,000 years, said Neff, who is also a faculty member in CU-Boulder's Environmental Studies Program. While some fine-grained dust from Asia periodically falls on Colorado's San Juans, the abundance of larger-sized dust particles in the lake sediments there indicates most of the dust originated regionally in the Southwest, said the authors.

While droughts can trigger erosion and increased dust deposition, western U.S. droughts during the past two centuries have been relatively mild compared to droughts over the past 2,000 years, Neff said. Instead, the increased dustiness in the West coincides with intensive land use, primarily grazing, according to radiocarbon dating and lead isotope analysis of soil cores retrieved from lakebeds, he said.

"There were an estimated 40 million head of livestock on the western rangeland during the turn of the century, causing a massive and systematic degradation of the ecosystems," said Neff. The 1934 Taylor Grazing Act that imposed restrictions on western grazing lands coincided with a decrease in accumulation rates of the San Juan lake sediments in the study -- a decrease that continues to today, he said.

The study also shows more than a five-fold increase in nutrients and minerals in the lakebed sediments during the last 150 years, said Neff. Increases in nitrogen, phosphorus, potassium, calcium and magnesium -- byproducts of ranching, mining and agricultural activity - have been shown to change water alkalinity, aquatic productivity and nutrient cycling.

In the Niwot Ridge alpine region west of Boulder, for example, CU-Boulder researchers have observed increased algal growth in streams and lakes as a result of rising nitrogen deposition, as well as changes in the composition and diversity of wildflowers on the tundra. "Because these types of inputs have the potential to increase plant growth, the ultimate outcome of such depositions could change the fabric of our ecosystems," said Neff.

Excessive dust also can cause significant human health problems, including lung tissue damage, allergic reactions and respiratory problems, Neff said.

The San Juan lakes are located in an area dominated by rocky talus slopes with little soil and vegetation at about 13,000 feet in elevation and are located downwind of several major U.S. deserts like the Colorado Plateau and the Mojave. The site was chosen in part because the San Juans experience frequent wintertime dust deposition events -- usually between four to seven episodes annually, Neff said.

A study published in Geophysical Research Letters in 2007 involving co-authors of the Nature Geoscience paper, including Neff, showed wind-blown dust from disturbed lands in the Southwest shortened the duration of San Juan mountain snow cover by roughly a month. "The dust we see in these lakes is the same dust that causes earlier spring snowmelt here, so we can now definitively say that humans are in large part responsible for this melt," said Neff.

"There seems to be a perception that dusty conditions in the West are just the nature of the region," said Neff. "We have shown here that the increase in dust since the 1800s is a direct result of human activity and not part of the natural system."

Comment: The researchers present a reasonable explanation for a dust increase, but we want to offer additional information for your consideration.

From Tunguska, the Horns of the Moon and Evolution by Laura Knight-Jadczyk.

"It has been suggested that the current "climate change" issues are due to the earth moving through cosmic dust clouds. It could even be that such things as "chemtrails" are a result of such dust loading in the upper atmosphere."

Post excerpt made by Laura Knight-Jadczyk in forum thread Cold, bad harvest, famine and then the Black Death.

Clube suggests that the reason for the climate issues are that the earth moves into a "band" of dust long before it begins to encounter impactors and that climate cooling itself is a precursor to more catastrophic activity.

From Cosmic Turkey Shoot by Laura Knight-Jadczyk.

Okay, now let's take a look at Victor Clube's summary of the problem. He writes:

Asteroid strikes, though important, are not the most serious short-term risk to mankind or civilization

Every 5-10 generations or so, for about a generation, mankind is subject to an increased risk of global insult through another kind of cosmic agency.

This cosmic agency is a "Shoemaker-Levy type" train of cometary debris resulting in sequences of terrestrial encounters with sub-km meteoroids.

While the resulting risk is ~ 10%, the global insults take the form of (a) multiple multi-megaton bombardment, (b) climatic deterioration through stratospheric dust-loading, not excluding ice-age, and (c) consequent uncontrolled disease/plague.

The sequence of events affecting involved generations is potentially debilitating because, whether or not the risk is realised, civilization commonly undergoes violent transitions eg revolution, migration and collapse.

Subsequently perceived as pointless, such transitions are commonly an embarrassment to national elites even to the extent that historical and astronomical evidence of the risk are abominated and suppressed.

Upon revival of the risk, however, such "enlightenment" becomes an inducement to violent transition since historical and astronomical evidence are then in demand.

Such change and change about in addition to the insult is evidently self-defeating and calls for a procedure to eliminate the risk.

Our technological ability to counter (a) multiple multi-megaton bombardment and (b) stratospheric dust-loading should therefore be explored.

The very short lead-time commonly associated with the detection of sum-km meteoroids approaching the Earth implies countering procedures which differ from those associated with catalogued km-plus asteroids and comets.

So, the question is: if there is even a 10 % chance that we are facing a Shoemaker-Levy type event, why isn't anybody doing anything about it?

Students from the Technion-Israel Institute of Technology to save the Earth 

The Engineer
Mon, 25 Feb 2008 15:48 EST

Nine students from the Technion-Israel Institute of Technology have developed a model spacecraft for deflecting objects falling from space.

The model has been created in response to the asteroid Apophis which scientists believe will collide with Earth in 2036, and was presented at a competition of NASA and the American Institute of Aeronautics and Astronautics.

The initial plan would put the craft into space in 2020 where it will approach the asteroid and launch two penetrating devices. These will deliver equipment including a specially adapted camera, transmitter and antenna. Air bags will be used to safely deliver the equipment and also will be attached with solar panels to power the equipment.

The equipment will collect data on the location and composition of the asteroid and relay it back to Earth. If needed the spacecraft can again approach the asteroid in 2025 to divert the asteroid from its path using the gravitational pull of the spacecraft. The asteroid will pass the Earth in 2029 before returning in 2036 and the team aim to change the path of the asteroid during this pass.

According to Dr Alexander Kogan, who guided the students, the craft will use its ion thrusters to hover 200-300m from the asteroid for four months. Using the mass of the spacecraft, combined with the effect of Earths' gravity, the craft will pull the asteroid out of its previous path.

'The spacecraft is what will make the difference,' said student Lior Avital. 'It will divert the asteroid one kilometre and with the help of the Earth, in seven years - 7,000km.'

Alternatives such as blasting the asteroid with a nuclear bomb were also considered, but the group believed the danger posed by two large asteroids or many small ones would be much greater. Diverting the asteroid by connecting powerful motors to it was also ruled out as the solution was deemed too expensive and complicated.

Flashback: Asteroid dust may influence weather- may play 'more important climate role than previously recognized' 

Sandia National Laboratories
Thu, 25 Aug 2005 18:24 EDT

Albuquerque, N.M. - Dust from asteroids entering the atmosphere may influence Earth's weather more than previously believed, researchers have found.

In a study to be published this week in the journal Nature, scientists from the Australian Antarctic Division, the University of Western Ontario, the Aerospace Corporation, and Sandia and Los Alamos national laboratories found evidence that dust from an asteroid burning up as it descended through Earth's atmosphere formed a cloud of micron-sized particles significant enough to influence local weather in Antarctica.

©Sandia

The asteroid's dust trail as seen by lidar at Davis, Antarctica. The plot shows the strength of the vertical laser light scattered back from the atmosphere as a function of time and altitude above mean sea level. The dust trail, blown by the stratospheric winds, moved through the beam.

Micron-sized particles are big enough to reflect sunlight, cause local cooling, and play a major role in cloud formation, the Nature brief observes. Longer research papers being prepared from the same data for other journals are expected to discuss possible negative effects on the planet's ozone layer.

"Our observations suggest that [meteors exploding] in Earth's atmosphere could play a more important role in climate than previously recognized," the researchers write.

Scientists had formerly paid little attention to asteroid dust, assuming that the burnt matter disintegrated into nanometer-sized particles that did not affect Earth's environment. Some researchers (and science fiction writers) were more interested in the damage that could be caused by the intact portion of a large asteroid striking Earth.

But the size of an asteroid entering Earth's atmosphere is significantly reduced by the fireball caused by the friction of its passage. The mass turned to dust may be as much as 90 to 99 percent of the original asteroid. Where does this dust go?

The uniquely well-observed descent of a particular asteroid and its resultant dust cloud gave an unexpected answer.

On Sept. 3, 2004, the space-based infrared sensors of the U.S. Department of Defense detected an asteroid a little less than 10 meters across, at an altitude of 75 kilometers, descending off the coast of Antarctica. U.S. Department of Energy visible-light sensors built by Sandia National Laboratories, a National Nuclear Security Administration lab, also detected the intruder when it became a fireball at approximately 56 kilometers above Earth. Five infrasound stations, built to detect nuclear explosions anywhere in the world, registered acoustic waves from the speeding asteroid that were analyzed by LANL researcher Doug ReVelle. NASA's multispectral polar orbiting sensor then picked up the debris cloud formed by the disintegrating space rock.

Some 7.5 hours after the initial observation, a cloud of anomalous material was detected in the upper stratosphere over Davis Station in Antarctica by ground-based lidar.

"We noticed something unusual in the data," says Andrew Klekociuk, a research scientist at the Australian Antarctic division. "We'd never seen anything like this before - [a cloud that] sits vertically and things blow through it. It had a wispy nature, with thin layers separated by a few kilometers. Clouds are more consistent and last longer. This one blew through in about an hour."

The cloud was too high for ordinary water-bearing clouds (32 kilometers instead of 20 km) and too warm to consist of known manmade pollutants (55 degrees warmer than the highest expected frost point of human-released solid cloud constituents). It could have been dust from a solid rocket launch, but the asteroid's descent and the progress of its resultant cloud had been too well observed and charted; the pedigree, so to speak, of the cloud was clear.

Computer simulations agreed with sensor data that the particles' mass, shape, and behavior identified them as meteorite constituents roughly 10 to 20 microns in size.

Says Dee Pack of Aerospace Corporation, "This asteroid deposited 1,000 metric tons in the stratosphere in a few seconds, a sizable perturbation." Every year, he says, 50 to 60 meter-sized asteroids hit Earth.

Peter Brown at the University of Western Ontario, who was initially contacted by Klekociuk, helped analyze data and did theoretical modeling. He points out that climate modelers might have to extrapolate from this one event to its larger implications. "[Asteroid dust could be modeled as] the equivalent of volcanic eruptions of dust, with atmospheric deposition from above rather than below." The new information on micron-sized particles "have much greater implications for [extraterrestrial visitors] like Tunguska," a reference to an asteroid or comet that exploded 8 km above the Stony Tunguska river in Siberia in 1908. About 2150 square kilometers were devastated, but little formal analysis was done on the atmospheric effect of the dust that must have been deposited in the atmosphere.

The Sandia sensors' primary function is to observe nuclear explosions anywhere on Earth. Their evolution to include meteor fireball observations came when Sandia researcher Dick Spalding recognized that ground-based processing of data might be modified to record the relatively slower flashes due to asteroids and meteoroids. Sandia computer programmer Joe Chavez wrote the program that filtered out signal noise caused by variations in sunlight, satellite rotation, and changes in cloud cover to realize the additional capability. The Sandia data constituted a basis for the energy and mass estimate of the asteroid, says Spalding.

The capabilities of defense-related sensors to distinguish between the explosion of a nuclear bomb and the entry into the atmosphere of an asteroid that releases similar amounts of energy - in this case, about 13 kilotons - could provide an additional margin of world safety. Without that information, a country that experienced a high-energy asteroid burst that penetrated the atmosphere might provoke a military response by leaders who are under the false impression that a nuclear attack is underway, or lead other countries to assume a nuclear test has occurred.

More detailed papers are slated for the Journal of Geophysical Research and the Journal of Meteoritics and Planetary Science, Pack says.

Flashback: Planetary Defense: Preventing a World of Trouble 

Salvatore A. Vittorio
CSA
Fri, 25 Nov 2005 19:21 EST

Our mission, should we choose to accept it: (1) Make up to six billion people understand the danger that faces this world. (2) Make them care enough. (3) Keep them caring long enough for it to matter. (4) Give them what they need to stop what's coming.

- Larry Niven, February 20, 2004 (from a presentation at the 2004 Planetary Defense Conference, sponsored by the American Institute of Aeronautics and Astronautics)

I. Introduction - The Threat

Planetary defense encompasses protecting the Earth from potential destruction due to impact by a large piece of space debris. Astronomical telescopes and deep space radar systems have verified the existence of a large number of near Earth objects (NEOs), such as asteroids, meteoroids, and comets that potentially could destroy most life on Earth. Where NEOs intersect Earth's orbit, there exists a risk of a collision. [1] An asteroid with a diameter of 1-10 km would strike the Earth with a power rivaling the strength of a multiple warhead attack with the most powerful thermonuclear explosives known to man. Computational fluid dynamics studies have indicated that an ocean strike by such an asteroid may create a gigantic tsunami that would flood and obliterate coastal regions. Perhaps even more significantly, a land strike may eject a massive dust cloud, rivaling that from the most powerful volcanic explosion, which could seriously affect climate on the scale of two to three years. It could alter our biosphere to the point that life as we know it would cease to exist. As recently as 1998, the astronomical and astrophysics community thought that most of the known NEOs do not pose a near-term threat, and therefore do not present any danger to the Earth and its biosphere. However, the relatively recent collision of the comet Shoemaker-Levy 9 with the planet Jupiter on July 16, 1994, and continuing discoveries of non-cataloged asteroids passing near Earth without any advanced warning, have increased concerns. It is worthwhile to note that one striking feature of practically every celestial body in our solar system is the abundance of impact craters. [2]

Geological evidence and observations of planetary bodies confirm the existence of a threat, albeit small, that Earth could one day be struck by a comet, meteor, or asteroid on a collision course from space that would be large enough to cause widespread destruction of modern society. In the last 100 years, a massive impact took place in Siberia (Tunguska, 1908) that devastated 2000 square kilometers and carried the destructive force of 12.5 megatons of TNT. This impactor was only 60 meters in diameter. The Earth's surface still shows scars of previous larger-scale impacts. A 100-meter diameter meteor over 20,000 years ago is believed to have caused the Meteor Crater in Arizona. In the more massive Cretaceous-Tertiary impact (K-T impact), a 10-km diameter object struck off the Yucatan Peninsula some 65.5 million years ago. Scientists found the crater around 1995 using seismic monitoring equipment designed to hunt for oil. Probably the size of a small city, the Chicxulub impact is widely believed to have triggered a mass dinosaur die-off, either through a global firestorm caused by earthquakes releasing pockets of methane set afire by lightning, or through massive long-term environmental changes. The impact likely also triggered giant tsunamis across the ocean and earthquakes that reverberated around the world. While such enormous impacts are certainly infrequent, objects with diameters of approximately 1 km can be expected to intercept the Earth every 100,000 years. [3]

Some thought and planning, therefore, is needed to provide a reasonable level of protection against such disastrous events. Identification and cataloging of NEOs and celestial bodies is an important first step. Observation and tracking of small (1 km or less) objects is a difficult task given the low albedos of the target bodies and their small size. However, accurate long-term orbital prediction models must be developed to allow for adequate response time. NASA and the California Institute of Technology's Jet Propulsion Laboratory (JPL) in Pasadena, California, maintain an active list of NEOs sorted by a weighted scale indicating their approach distance and destructive potential (the Palermo Technical Impact Hazard Scale). In 2003, over 10 objects were identified that passed within 1.5 times the distance from the Earth to the Moon (1 lunar distance = 384,000 km). The smallest objects in the JPL database are 20 meters in diameter with typical NEOs in the 500-meter to 1-km diameter range. [14, 3] Currently, the highest active object on the Palermo Technical Impact Hazard Scale (Palermo scale) is asteroid 2004 VD17, with a cumulative Palermo scale value of -1.06. [4]
[Note 1]

NASA has proposed new observatories that will be able to detect even smaller objects. For example, NASA's Revolutionary Aerospace Systems Concepts (RASC) program conducted a study called CAPS (Comet Asteroid Protection System) that promoted a lunar telescope installation for conducting NEO detection research. The question remains what should be done if a planetary impactor on a collision course with Earth is actually confirmed. [3]

II. Categorizing the Threat

The large number of circumstances in which a NEO might threaten the Earth can be characterized by several parameters, such as warning time; NEO size, mass, and orbital parameters; impact location; certainty of impact; NEO orbital class (e.g., those of the Atens, Apollo, and Amor families of asteroids, the trans-Neptunian objects, and the comets); NEO composition; and NEO spin.

The concept of a response decision chart (see Figure 1), constructed by researchers Peter Nicolas, Andrew Barton, Douglas Robinson, and Jean Marc Salotti, could be applied to break down the problem into manageable sub-categories, where each branch of the tree corresponds to a particular class of NEO threat scenarios for which response options would be similar. [7] Thus, for any threat scenario, it can be determined what responses are appropriate. The aim of such a classification tree is to provide a global tool providing more useful information to the policy maker by laying down in a simple but comprehensive way all possible NEO impact scenarios, consequences, and responses. In addition to the above parameters, other parameters might require expert scientific advice, such as detectability and destructibility. [6]

Figure 1: Response decision chart (simplified version) [7]

Click here for complete chart

The specific classification breakdown of the parameters of warning time, damage potential, hit location, and responses are discussed below. In addition, another parameter, certainty of impact, is also addressed.

A. Warning time

The classification of 'Short' is intended for threats with less than one year of warning time. Such scenarios exclude the development of new space missions, allowing only ground-based responses. If the warning time is in the scale of decades, there are many opportunities for both space-based and Earth-based mitigation efforts. The category named 'Medium' encompasses the warning time frame from 2 to 30 years, presenting the possibility of new space missions with existing technology. The 'Long' warning time category encompasses all NEO impact scenarios with the impact occurring more than 30 years in the future, so one can only speculate about far future mitigation technologies and approaches. [6]

B. Damage potential

This refers to the effects that an NEO would have if it impacts the Earth. The effects are largely dependent on the size and mass of the NEO. The 'Large' category includes all NEOs larger than 2 km since these objects would cause very large disasters and therefore require global response efforts. The 'Small' category is intended to include any NEO threats that would be of local or regional significance. It is generally thought that such NEOs can be successfully deflected or destroyed with modern technology if there is sufficient warning time. Excluded are the very small NEOs that would burn up in the Earth's atmosphere (less than 30 m), since these require little or no response. [6]

C. Response limitations

The branches at this point of the tree in Figure 1 distinguish between the different types of space-based responses. The category named 'Deflectable' is for NEOs that are small enough or with long enough warning time to enable deflection of the body with sufficient delta-v to prevent its impact with Earth. The object's accessibility should also be taken into account. When possible, this category is the most desirable response since it doesn't affect the Earth. 'Destructible' is a possibility for objects that are not deflectable. In some cases the NEO is held together too weakly to be able to absorb the energy transfer required for deflection. There are also cases where 'Partially Destructible' is a possibility. Reducing the NEO into many smaller fragments by nuclear blasts may reduce the scale of disaster on Earth, although it also risks spreading the effects (including nuclear fallout) over a wider area. Finally, 'Neither' is included for the cases where the NEO is neither destructible nor deflectable. [6]

D. Hit location

The two most important distinctions for a NEO striking the Earth's surface are between 'Ocean' impacts and 'Land' impacts. The most devastating possible effect of an ocean impact would be a tsunami, which would damage coasts in the region or around the world. On the other hand, a similar size land impact would lead to more debris and dust being ejected into the atmosphere, likely causing more severe climatic changes. Accurate prediction of the impact location is not always possible since it depends on accurate orbital parameters for the NEO. In some cases, data will be insufficient to determine whether the NEO will hit the land or the ocean (due to long warning times, incomplete orbital observations, etc.). A dispersed impact zone including both ocean and land regions is also possible. Furthermore, the presence of the Earth's atmosphere may also lead to dispersion of the body over a wide area. [6]

E. Certainty of impact

Another important tool for categorizing the Earth impact hazard associated with newly discovered NEOs is the Torino Scale, which is equivalent to the "Richter Scale" but for NEOs. This scale was created by Professor Richard P. Binzel at the Massachusetts Institute of Technology and revised at an international conference on NEOs held in Torino, Italy, in June 1999. The Torino scale utilizes numbers that range from 0 to 10, where 0 indicates an object that has a zero or negligibly small chance of collision with the Earth, or that is too small to penetrate the Earth's atmosphere intact in the event that a collision does occur. A 10 indicates that a collision is certain, and the impacting object is so large that it is capable of precipitating a global disaster. An object is assigned a value based on its collision probability and its kinetic energy (proportional to its mass times the square of its encounter velocity). [6]

III. Some Possible Response Options

For all we know, a large asteroid may be heading this way right now, and you'll never get this [conversation] on the air. The danger of asteroid or comet impact is one of the best reasons for getting into space. I'm very fond of quoting my friend Larry Niven: 'The dinosaurs became extinct because they didn't have a space program.'And if we become extinct because we don't have a space program, it'll serve us right!

-Arthur C. Clarke

Deflecting or destroying a NEO in space is still in the realm of science fiction. However, if an impact does occur, many steps can be taken on Earth to mitigate its effects. It would be best, of course, to avoid the initial catastrophe. The idea of the deflection strategy is to change the orbit of the NEO in order to prevent an impact with Earth. According to C. Gritzner deflection is the only solution in case of a NEO larger than about 100m, because the destruction strategy might worsen the situation. [15] However, the deflection of a NEO years ahead of its impact requires that detection be achieved soon enough and its orbital elements precisely computed.

Destruction - the second best strategy - refers to breaking the object into many pieces. The destruction of the NEO body is generally proposed when there is very little time left before impact, weeks or months, so that any deflection would be insufficient. The timing of the interception is crucial in the response decision process and depends on the threat's detection time. If there is time for an interception, then a space-based response is possible; if not, then the only solution is to evacuate the impact location. [6]

A. Space-based responses Space-based response strategies to threatening NEOs can be summarized as follows:

1. Non-nuclear or Kinetic deflection: A non-nuclear novel concept is employed to deflect an NEO. Alternatively, for kinetic deflection, a large spacecraft or several spacecraft, or a missile, is/are sent to impact and deflect the NEO using only kinetic energy.

2. Nuclear deflection: Nuclear explosions are triggered at a distance, on the surface or after penetration, provoking the ejection of rocks from the NEO, which in turn reacts by a small deflection.

3. Nuclear destruction: In some cases, the explosion might cause the partial fragmentation or even the pulverization of the NEO.

4. Mass driver: If the action time is significant, it is possible to land a device that would regularly eject some matter from the asteroid and therefore slowly deflect it from its original trajectory.

5. Billiards shot: This option consists of deflecting a small asteroid, putting it on a collision course with the Earth-threatening NEO.

The selection of the best option depends on the time available for action and the diameter (size) of the NEO. The effects of a large blast near a NEO depend not only on the NEO's mass but also on its composition and structure. For rubble-pile asteroids - loose aggregations of rock, presumably the result of a collision - deflection is impractical. In cases where deflection is desired, nuclear blasts should not be triggered too close to the NEO to avoid its fragmentation. When NEOs are too large for nuclear destruction or deflection, the billiards shot option is theoretically possible but remains uncertain in terms of accuracy and technical feasibility. In this option, a small NEO's orbit is changed in order to achieve a collision with the (larger) NEO on a collision course with Earth. This method could deflect even 10-km-class NEOs. [6]

Particular scenarios or specifics concerning the above space-based response strategies are discussed and/or considered below. Focus is placed mainly on threatening near-Earth asteroids (NEAs). Near-Earth asteroids, a subset of the NEOs, are asteroids whose orbit intersects Earth's orbit and which may therefore pose a collision danger, as well as being most easily accessible for spacecraft from Earth. [NEA Information]

1. Non-nuclear and kinetic deflection concepts

A. Mirror Ablation approach One method of deflecting Earth-threatening asteroids uses a solar collector that focuses sunlight on the surface of the asteroid. This strongly heats a small spot, and vaporizes enough material so that the thrust from the expanding jet of gas and dust can, over a period of years, divert the asteroid. The primary difficulty with this scheme is the danger of fouling of the last optical element in the system by evaporated material. Overall, this scheme does not involve a large extension of present technology. It is effective on comets, the orbits of which are perturbed by forces generated in reaction to the jets of gas and dust that emanate from their surfaces during passage through the inner solar system [16, 17, 18].

Asteroids, by definition, do not emit such jets, and their orbits are therefore much more predictable than those of comets.However, if some means were found to create such comet-like jets even on asteroids, the thrust of these jets could be used to steer a threatening asteroid out of a collision course with the Earth. This is the basic idea behind the Mirror Ablation approach, shown in Figure 2. Sunlight, freely available in space, could be concentrated on the surface of the asteroid, just as a burning glass can raise the temperature of wood and leaves on the Earth's surface to the ignition point. If the sunlight is sufficiently concentrated, even the surfaces of rocky asteroids may become hot enough to evaporate and develop a steady thrust that will, over time, impart a velocity increment sufficient to avert a collision with the Earth. [Note 2] [8]

Figure 2. Schematic illustration of the basic components of the Mirror Ablation Mission to deflect an Earth-threatening asteroid [8]

B. Kinetic energy (KE) projectile

This asteroid deflection technique is based on a fictitious threat scenario. The mission objective is to prevent the collision of the virtual 200-meter binary asteroid Athos with Earth on February 29, 2016. The detection date of the asteroid is assumed to be February 22, 2005, which gives a short span from the time of detection to the launch date of the deflection spacecraft. The technique is based on the momentum transfer from an impacting spacecraft on the hazardous object. The impacting process coincides with the ejection of crater material, where the total momentum change of the target object is the momentum of the escaping ejecta plus the momentum carried with the projectile. For nonporous targets the ratio between ejecta momentum and projectile momentum can be as large as 13, whereas for porous targets this could be decreased to 0.2, yielding a momentum enhancement factor of 14 and 1.2, respectively. [23] In this particular scenario a momentum enhancement factor of 3 is assumed, which was deduced from the physical properties of Athos and experimental factors for analogous materials. [Note 3] A state-of-the-art launch system arsenal is thus envisioned that comprises two rockets, which could both be used for KE interaction. These are the American Delta IV Heavy and the European Ariane 5 capable of launching 12.4 and 12 tons (planned for 2006) into geostationary transfer orbit (GTO), respectively. A KE mission opportunity is identified, which maximizes the product of spacecraft mass and relative velocity (in Athos' direction of flight) when impacting on Athos in April 2012. The launch from GTO is scheduled for December 27, 2011.

A velocity change of 787 m/s, applied during perigee passage, is required to get onto an interplanetary orbit. After a low-demanding deep space maneuver (4 m/s) the spacecraft swings by Earth on February 15, 2012. This gravity assist from Earth enables the high energy impact with Athos on April 5, 2012. [Note 4] Since launch systems cannot be started within short intervals, the spacecraft are to be launched into geostationary transfer parking orbits, beginning one year in advance of interplanetary transfer to Athos. Last, but not least, it has to be ensured that the projectile shelling will not cause fragmentation of Athos into large boulders that possibly remain on collision course with Earth. The technology readiness level of KE projectiles has been evaluated as high, and no technological problems are expected. Possible development efforts could deal with the shape and composition of a KE spacecraft. [9]

2. Nuclear Deflection Concept - An asteroid interceptor

In one particular study a conceptual design was developed for an asteroid interceptor vehicle using a nuclear explosive. [10] The proposed target for this mission is the 200-m asteroid threat object Athos (see above). The proposed interceptor's basic functions include locating the NEO, delivering a nuclear device to it, exploding the nuclear device at the appropriate time/location, and verifying the system's performance. In order to reduce interceptor propellant requirements, a direct intercept approach, rather than a rendezvous approach, was chosen in this scenario. Direct intercept permits the use of a relatively large nuclear device, but places severe constraints on the intercept conditions and affects the potential accuracy of weapon delivery. This study limited the interceptor launch to existing vehicles in order to enable a near-term deployment. An overall mission objective is to provide opportunities for multiple shots, if necessary, which implies that it would be useful to verify the performance of each shot to determine if another shot is required. For this reason, it was decided to provide a separate cruise stage on the interceptor for the purpose of sensing the NEO and the kill vehicle that carries the nuclear weapon, and relaying observations back to Earth. Other reasons for including the cruise stage are a desire to lighten the kill vehicle and the possible use of cooperative target tracking between the cruise stage and kill vehicle.

The proposed interceptor consists of a cruise stage and a kill-vehicle stage. The function of the cruise stage is to perform spacecraft housekeeping for the interceptor during transit, relay data to and from the kill vehicle during endgame, and verify system performance during and shortly after intercept. The function of the kill-vehicle stage is to deliver the weapon to the desired target point and detonate. A mass goal for the entire interceptor stack of 6000 kg is based on the launch vehicle capacity for a Delta IV Heavy and the intercept trajectory requirements. Conceptual mass estimates for both interceptor stages were developed using the spreadsheet-based Aerospace Concurrent Engineering Model (CEM). [19] This model utilizes historical spacecraft design relations and basic physical principles to parametrically estimate space vehicle mass.

Payload capacity for the nuclear device was estimated by systematically increasing the weapon mass until a launch mass limit of 6000 kg was reached for the entire launch stack. Based on the analysis, the estimated weapon capacity for the proposed conceptual design is 1500 kg or an approximately 1.9 megaton yield with a warhead optimized for neutron emission. [20] High neutron emission enables maximum momentum transfer to the NEO target. [10]

3. Nuclear Destruction Concept - Nuclear fragmentation

The equations used to model the catastrophic fragmentation of a near-Earth solid body asteroid derive from the work of Thomas J. Ahrens, California Institute of Technology, and Alan W. Harris, Jet Propulsion Laboratory, [21] based on the assumption that an explosive device is placed deep enough below the asteroid's surface to produce near-optimum fragmentation. The location for optimum fragmentation is generally considered to be the target object's geometric center.

This assumes ideal destruction conditions, namely, (1) the asteroid is a perfectly spherical homogeneous structure, (2) the explosive charge is placed at the exact geometric center, and (3) the explosion fractures the target body into pieces no larger than 10 meters in diameter. Although open to debate, it is generally assumed that fragments of this size would be much less likely than the original body to survive entry through Earth's atmosphere. Even if any fragments did reach the ground, the impact of these relatively small objects, spread over a large area, would be less damaging from a global point of view than a single massive asteroid strike.

Asteroids greater than 2 km in diameter would be considered catastrophic to the Earth. Unfortunately, there are currently no existing nuclear devices that could catastrophically fragment an asteroid greater than 2 km in diameter.

One idea considered to place an explosive device at the geometric center of an asteroid that can be destroyed (those about less than 2 km in diameter) of the target body is to use the same technology that is found in the " long-rod bunker buster" ordinance that the U.S. military employs against underground facilities. This idea has the advantage of not requiring a delta-v breaking maneuver to rendezvous with and "soft" land on the target. Instead the outbound kinetic energy is used to bury the device to the optimum depth. It is assumed that the explosive device can be successfully delivered kinetically to the "center" of a 200 m diameter asteroid; anything larger may require the use of some sort of drilling or auger device.

4. Mass Driver Concept - The Modular/Swarm Architecture

A modular architecture of smaller devices can provide the means to build up defensive capability immediately while allowing for system improvements and modifications over time. An approach conceptualized by SpaceWorks Engineering, Inc. (SEI, Atlanta, Georgia) is to subtly change the orbit of a potential impactor far from the point of impact. Mass drivers landed on the impactor will be used to eject small pieces of the asteroid's own mass to gradually affect its velocity. SEI advocates the use of multiple, "small" lander spacecraft to provide a modular, scalable, and rapid response to planetary defense.

Their solution consists of hundreds or thousands of identical spacecraft that will intercept the target body and conduct mass driver/ejector operations to perturb the target body's trajectory to the point where an impact with Earth can be avoided. In the nominal configuration, each spacecraft will be independently controlled and powered, but will work in loose coordination with other members of the network. The spacecraft will be nuclear powered, possibly pre-deployed outside of low Earth orbit (LEO) (likely an Earth-Moon or Earth-Sun libration point), and be capable of using chemical propulsive boost to rapidly intercept an incoming target. Upon arrival, each spacecraft will begin to eject small amounts of mass from the asteroid that will, over time, slightly change target's heliocentric (Sun-centered) orbit so that impact is avoided. SEI's modular approach offers the unique advantages of overall mission reliability through massive redundancy, economies-of-scale during spacecraft production, flexible and practical launch and transfer to an on-orbit pre-deployment location, a tailorable response depending on the size and nature of the incoming threat, and the production of only small bits of ejecta that will not independently survive Earth atmospheric entry. Trade studies conducted by SEI have assumed that the launch rail that will eject the mined mass from the impactor (asteroid) should be as long as reasonable, but launch packaging and stiffness considerations will limit it to no more than 10 meters. As the launch velocity increases for a given shot mass, the mass driver power increases in a cubic fashion, thus driving up the size and mass of the mass driver capacitor units. The energy (or work) used to accelerate the ejecta increases proportional to the square of the launch velocity, thus requiring a larger spacecraft power supply (or alternately a longer cycle time between shots) to recharge the capacitor units. The compressive force on the lander and rail increases relative to the square of the launch velocity. The downward force will benefit the mining process to some degree, but an excessive compressive load would require a massive lander structure and thus exacerbate the launch and deployment problem for the spacecraft.

Based on these results, SEI has established a working baseline of a 10-meter launch rail, 0.5-kg ejecta mass per shot, and a launch velocity of 1000 m/s (well within the capability of today's rail launchers). For this configuration, the ejecta will undergo an acceleration of almost 5100 Earth g's (gravitational acceleration) for a period of 0.02 seconds, which means a mass driver power of 12.5 megawatts per shot. [11]

5. Billiards Shot Concept - Artemis target

The billiards shot strategy consists in deflecting a smaller asteroid (the striker) so that it impacts and destroys the threatening asteroid before the predicted collision with Earth. The Artemis asteroid is considered here, which is 119.1 km in diameter, and has the potential of striking Earth in 2033. The kinetic energy of a small striker is more powerful than nuclear weapons for the destruction of big NEOs. Ten tons of nuclear energy is roughly equivalent to 10,000 kilotons of TNT. A 100 meters large asteroid weighs approximately 1 megaton. If the relative velocity at impact is 20 km/s, the kinetic energy is about 100,000 kilotons of TNT, which is 10 times more than the energy of a strong nuclear blast. Asteroids as small as 100 meters in diameter, therefore, could be used for a billiards shot. In the case of Artemis, a 100-meter diameter asteroid is sufficient. Considering a plane change maneuver to match Artemis's orbital plane, followed by a modification of the semi-major axis, it has been shown that the 1999 VK12 is the best striker of the billiards shot against Artemis. The closest encounter occurs in April 2027. [Note 5] Theoretically, the billiards shot option is cheap in terms of energy; however the feasibility of the maneuver has yet to be checked. In terms of energy, it could sometimes be easier to deflect a small striker and to put it on a collision course with a big target asteroid than to deflect the latter in order to avoid the collision with our planet. In the case of Artemis, however, the data are not ideal.

In general, in order to deflect the striker, numerous nuclear blasts have to be triggered close to it. The striker asteroid should be able to resist the numerous blasts. It should not be a rubble pile or a friable asteroid. Since the composition of a potential striker is usually unknown, a specific mission should be designed to assess its ability to play the striker role. Complementary studies remain to be performed to assess astronautic capabilities and to examine the billiards shot without exact matching of the planes. However, in the case of a real threat, the billiards shot could be the only option that allows deflection or destruction of a large NEO (greater than 10 km) at relatively short notice. [12]

Figure 3: Orbital paths of the Earth (small circular orbit), Artemis (top), and 1999VK12 (bottom) and positions around the sun in April 2027 [12]

The selection of the best of the above five options depends on the time available for action and the diameter of the NEO. For space-based responses, the key parameter is the action time, which is as a function of the warning time and orbital parameters. Figure 4 is a graph showing space-based responses. [6]

Figure 4: Selection of the best option according to the action time (in years) and the diameter of the NEO (in km) [6]

B. Earth-Based Responses

Of course, if a successful interception, destruction, or mass reduction to a safe level of the threatening near Earth object is impossible due to lack of time or incapability, then Earth based responses are the only recourse. Earth-based responses can be divided into two groups depending on the NEO disaster: (1) relocation of the endangered populations, and (2) sanctuary in appropriate shelters.
If the likelihood of a NEO impact with a particular region of the Earth is established, the most obvious step is to plan the evacuation of the population from that zone. Currently there are very few procedures for coping with this problem, and none at an international level. The International Strategy for Disaster Reduction (ISDR) is yet to recognize the NEO threat, although it has procedures to deal with large-scale disasters on an international level. [22] Furthermore there is no internationally agreed link in the NEO detection community between who would give the warning of an impact and these disaster response authorities. Thus, the time delay between confirmation of a detection and the official decision makers in government learning of the threat is probably on the order of days or weeks. The construction of shelters to protect the population is a last resort that would have to be attempted in desperate cases. Even in the other cases, in which a space mission is the main response option, a shelter plan would still need to be developed as a contingency. [6]

1. Evacuation and relocation

The term evacuation encompasses all emergency efforts to move people from the area prior to an impact. Depending on the impact's size, the time scale for evacuations would be hours to weeks. The concept of relocation refers to a broader effort to save not only humans but wildlife, cultural heritage, etc., and to establish a temporary or permanent habitat for them. The time scale for relocation is assumed to be enough for planning (weeks to decades). [6]

2. Shelters

The 'Shelter' response category refers to any attempts to provide protection from the effects of a NEO impact on Earth. Depending on the size of the NEO, there may be 'Long-Term' or 'Short-Term' sheltering. Long-term shelters are envisioned to sustain human life on Earth after a large impact has substantially changed the atmosphere and climate. This is in some ways analogous to attempts at supporting human life on other planets. Short-term shelters encompass all attempts to mitigate against the direct effects of the NEO's impact, such as a blast wave, earthquakes, etc. [6]

IV. Conclusion

It is extremely unlikely that Earth will be hit by a very large asteroid (size above 1 km) that would cause global destruction, but chances are much larger for impact with lesser asteroids (100 m or so in size) that would cause a local catastrophe. A sudden unpredicted impact may be the most probable scenario due to a currently incomplete NEOs survey. In terms of risk analysis, the main uncertainty comes from the incomplete knowledge of the number, size distribution and orbital parameters of the NEO population. The natural hazard of NEO impact could be mitigated by adequate advance action. Responding to the varying magnitudes of NEO threats involves a very broad range of disciplines and makes the planning for NEO responses a complex task. However, Earth-based responses to NEO threats can take advantage of existing natural disaster mitigation strategies applied to earthquakes, floods, hurricanes, etc. The magnitude of a NEO catastrophe could be much higher, ranging from a regional to a continental to a global scale, whereas traditional natural disaster consequences range from local to regional scales. A major step in assessing any NEO hazard is to identify the threatening object and to characterize it, either by Earth or space-based observing facilities, long enough before the possible impact to design and operate mitigation missions. Most attention to the NEO threat is currently focused on the detection issue, and the NEO response work has been almost exclusively on technology studies of possible space-based strategies. However, the problem of mitigating the effects of a large Earth-impact having large regional or even global consequences, and adapting international laws related to the choice and management of NEO response missions, needs to be tackled. [6] Given the fact that Earth encounters with near-Earth asteroids as early as 2027 or 2033 (see above) are possible, the window of opportunity for planning and organizing for such a possibility grows narrower with each passing year. In reality, we really don't know with absolute certainty when the next large asteroid (on the order of that of the K-T impact) will strike Earth. Therefore, the time to start preparing is always now.

In a paper deliv