Fri 2 January, 2004 15:48
TEHRAN (Reuters) - A meteorite has hit northern Iran causing minor damage to property but there were no immediate reports of casualties, state radio has said.
It said the impact sent locals in panic onto the streets in the northern town of Babol in Mazandaran province.
"A meteorite which hit Babol on Friday morning caused only some minor damage to residential units," radio said, without giving further details or citing any source.
It said the impact was felt up to one kilometre away. [...]
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Impact sites of the meteorites that crashed into Spain January 4 2003 |
January 5, 2004 - 11:54AM
Hundreds of Spaniards reported seeing balls of fire or incandescent objects fall from the sky today, emergency centres said.
Some of the objects were believed to have sparked fires. The phenomenon was reported on a stretch reaching from Galicia in the north-west to the Balearic Islands in the east.
The National Meteorological Institute said it had not observed anything unusual. Aviation authorities said they had no knowledge of any plane crash.
Astronomers at the University of Santiago de Compostela said they suspected a meteorite. No injuries were reported.
In northern Leon province, residents reported seeing a ball of fire light up the sky and explode in a mountainous area, igniting a fire and shaking house windows.
A similar explosion was heard near Palencia in the north.
Firefighters extinguished a blaze behind a roadside discotheque in the Castellon area.
Rescuers searched for wreckage of airplanes or unusual rocks in several places, but found no clues.
The National Meterological Institute said that its radars and satellite images showed nothing abnormal.
Astronomer Jose Angel Docobo said he suspected a meteorite weighing from 50 to 100 tonnes, which would have disintegrated on entering the atmosphere. [...]
Comment: El Mundo reports that it is estimated that the meteorite was the "size of a house" and up to 100 tons. It was reported across the full width of Spain with hundreds of witnesses seeing fireballs with "silver trails" streaking across the sky. Many also heard loud explosions that rattled windows and doors and felt the ground shaking.
Police hunt meteorite fragments
From correspondents in Madrid
The Australian
January 06, 2004
SPANISH police were combing parts of the country today after thousands of people reported seeing a "ball of fire" in the sky, prompting astronomers to speculate fragments had broken off a large meteorite.
Residents from areas as far apart as the northwestern coast and the south east Mediterranean coast had telephoned police to report seeing "a big ball of fire" roaring across the skies yesterday evening.
Experts believe the meteorite discharged some fragments into the atmosphere as it hurtled through space.
Police were concentrating their search for the fragments around Leon and Palencia in central Spain, the area above which the meteorite is believed to have disintegrated falling over as many as seven regions in an arc running from the northwest to the south east of central Spain.
Jose Angel Docobo, director of Spain's astronomy observatory in the western city of Santiago de Compostela, said the debris could have come from a meteorite weighing from 50 to 100 tonnes before disintegration. His observatory carried out a study eight years ago on a similar incident when a meteorite weighing an estimated 10 tonnes dropped debris over Spain.
Docobo believes the largest of the fragments, thought to be strewn over a radius of 100km, fell near the town of Molina de Aragon, near Guadalajara, 54km north of Madrid.
Comment: Also on this day it was reported:
A solar coronal mass ejection (CME) is en route to Earth today. It was hurled into space by an M7-class explosion near sunspot 536 on January 5th at 0345 UT. Sky watchers should be alert for possible auroras on January 6th or 7th when the CME sweeps past our planet.
Kendrapara (PTI): Three months after a meteor shot across the sky in Orissa’s coastal belt, fragments of its debris are still being recovered in Kendrapara district.
Four pieces, picked up by locals who had preserved them out of curiosity, have been recovered by panchayat representatives in Mahakalapada block, official sources said. The fragments when put together weigh 3 kg and are with panchayat officials now. Sarpanch Gagan Bihari Pradhan has been instructed to keep the fragments in safe custody and hand them over to the district administration.
The district administration had warned residents not to keep the meteorite pieces in their possession as they fell in the national treasure category. Private possession of such material would amount to penal offence, the administration warned.
So far, 10 fragments have been found from villages and paddy fields, the sources said.
Comment: While pieces were still being picked up in India, Iran was hit with a meteorite on Jan. 2nd, in the northern town of Babol in the Mazandaran province, as we reported here. We have been looking, but so far, it appears that all follow up information has been "hushed."
See the fifth page of this Signs Supplement for the amazing reports on Orissa. Laura's article Independence Day discusses the science behind what may be ahead... and if the C's are right about the comet swarm, then they are probably right about the wave... and what one needs to do to prepare, all of which is covered in the newly revised book, The Secret History of the Worl.
Great balls of fire, its a meteorite!
22 January 2004
AMSTERDAM — A large number of star gazers claim to have seen a large fireball shoot through cloud cover on Wednesday night in what experts believe was a meteorite falling to earth.
The Dutch Meteor Society (DMS) said the fireball probably took place somewhere above the Belgian-German border in Wallonia. It was seen in Limburg, eastern Belgium and Germany, Dutch news agency ANP reported.
The Leiden-based DMS also said the fireball was most probably due to a meteorite and ruled out the possibility that it was a broken fragment of a satellite or a rocket. A society spokesman based the claim on information supplied by US aerospace agency Nasa. [...]
A researcher with the European Space Agency (ESA) in Darmstadt, Germany, said the meteorite would have been about 10cm to 50cm in size. [...]
Comment: It was reported on January 21st, that we missed being hit by an asteroid by about 1.2 million miles. We have been assured that even if it hit the earth's atmosphere we would have only witnessed a bright flash of light. The lucky individual who spotted it is quoted saying, "It's hard to explain the excitement when you find a fast-moving asteroid." Indeed.
A crater from a meteorite that collided with earth about 1.5 billion years ago has been discovered in Finland by two amateur geologists. They estimate that original size of the crater may have been 20 and 25 kilometres wide after the impact.
Is it a bird, a spaceship or meteorite?
Presenter: Leon Compton
Wednesday, 18 February 2004
Just what exactly was it that people saw in our skies Tuesday morning? Albury based astronomer David Thurley believes it was most likely a meteorite
ABC Goulburn Murray was inundated with calls from people who saw a strange occurrence in the sky early Tuesday morning, we got calls from witnesses in Albury, Corowa, Benalla, Berrigan and the Buckland Valley..
Some called it a space ship, while others thought it had to be a meteorite - So what was it exactly? ABC's Leon Compton thought he would chat to Albury based astronomer David Thurley to see if he could put any light on the mystery..
"It does sound like a meteorite then, and they can be all sorts of colours. Like you can get reddish and orange sometime even green"
David explained the colour of the meteorite depends on how fast they are going.. "The faster they are going, the brighter the colour they will be, the more they will burn up very fiercely. So if they are a slow moving one - they might just glow red or yellow. And really going fast they go blue, green white sort of colours.." [...]
Fireball Reported over Germany
[N]umerous residents reported seeing a bright flash in the sky and hearing a loud sound like a thunderclap.
Callers to radio station SWR1 reported seeing green and blue lights at around 6.30am local time (11pm AEDT) in the states of Rhineland Palatinate and Baden-Wuerttemberg.
Scientists from the German air and space administration were hoping that cameras it has aimed at the skies might be able to provide them with evidence of what happened, though footage was not expected to be available until tonight at the earliest.
Walter Flury, from the European Space Agency, said the noise and lights indicate the possibility of a meteor fragment between 10 and 30 centimeters long hurtling through Earth's atmosphere. Whether it made impact would depend on a range of factors like if the piece was made of iron or stone, he said.
Comment: All kinds of assumptions are contrived when celestial objects become terrestrial objects. For example the meteorite that crashed through a man's home in Tulane, LA, September 27, 2003, sparked the following reaction:
"I'm in shock," Fausset said after learning the rock had been identified as a meteorite. "Oh, that's scary. I will certainly go to church this Sunday, because the Lord was certainly sending me a message."
These assumptions have real world effects, particularly when they are accompanied with coincidences with incredibly remote probabilities:
A Bolt From the Blue
There is no stranger true story on record than that of the sudden and dramatic manner in which a civil war was brought to an end in Nicaragua. The year was 1907 and [...] a military group was seeking to shoot its way into office.
The Rebels were making considerable headway under the astute leadership of General Pablo Castilliano. He had ample weapons, plenty of money, and an excellent background of military training.
General Castilliano and his forces were within easy striking distance of complete victory. The government forces had been defeated twice in quick succession, many of the troops had deserted and others were ready to throw down their arms if it looked like the rebels were going to win again. Castilliano and his officers had their troops strategically placed along a ridge overlooking the enemy positions. The blow which should bring them victory was timed for daylight the next morning. General Castilliano bade his staff good night and retired to his tent to set down a record of the day's events in his diary. At about ten o'clock he blew out his candle and went to bed.
A few minutes later the camp was lighted up as if by a gigantic flare. A flaming mass was streaking down from the clear night sky - coming straight for the camp. The terrified guard outside the General's tent yelled and threw himself to the earth.
The fireball struck squarely into General Castilliano's tent with a roar like that of dynamite. It blasted out a pit ten feet deep and about fifteen feet in diameter. The General died instantly. His guard lived for two days, long enough to confirm that it had indeed been a fireball from the sky, just as the other sentries claimed. Their story was later found to be true when pieces of the shattered meteorite were found in the pit.
The General's dramatic and almost unprecedented death demoralized his troops. They took it as a sign that their cause was in disfavor in Heaven and the rebellion collapsed overnight. It remains to this day the only known case where a war was brought to an end by direct intervention of a celestial object. [Strange World, Frank Edwards, p. 222, NY 1964]
Residents witness meteor shower
Friday, 20 February 2004
The spectacular sight of what was most likely a meteor breaking up in the sky captured the attention of several early risers on Tuesday, with three residents reporting the heavenly visit at 6am.
However, local viewers will be disappointed to learn that despite appearances, it did not pass or land nearby.
A spokesperson from Siding Spring Observatory at Coonabarabran said that reports of the sighting had come from across the state, and that given none had included a sonic boom, the object would have been high in the atmosphere and hundreds of kilometres away.
That didn't stop Lyndhurst resident Bronwyn Rhodes describing the sight as "absolutely beautiful".
She was driving down up Binni Creek Rd at the time and was spellbound by the flying object to the north.
"I've never seen anything like it," Ms Rhodes said. "I wish I had my camera with me. It was coming down in an arc and going to hit somewhere."
Even after it left her vision, she kept an eye out for any fires lit by pieces breaking off as it came down.
Cowra resident Richard Wells also saw the object, saying that it streaked slowly across the sky to the north at 6.03am.
"It was travelling in a straight line from west to east, approximately 10 degrees above the horizon and appeared to pass over Canowindra.
"It had a bright silvery tale trailing a larger circular leading edge, and appeared to break-up into an orange fireball about the direction of Mandurama."
Country-link coach driver Mick McCarthy at first thought the flaming object was a large aircraft on fire and about to crash.
He was driving his bus east towards Cowra from Grenfell when he sighted the object to the north of Broula Hill.
So far, there have been no reports of where the object landed.
Witnesses Report Seeing Fireball In Sky
Meteor Streaks Over Metro Area Around 6:30 PM
UPDATED: 8:29 AM MST February 26, 2004
DENVER -- If you saw something unusual in the night sky above Colorado Wednesay night, you weren't alone.
Many people called 7NEWS to report a fireball around 6:30 p.m. and the Museum of Nature and Science said it was likely a meteor.
"I did see the meteor as clear as day," said viewer Annmarie Maynard, who was in Westminster at the time. "I would say it came down in the mountains. It was not streaking across the sky but in a rather quick descent."
"I live on the Western slope in Crawford, and was traveling to Paonia at 6:30 last night, when in the northeast I saw a huge meteor fall and explode above the earth. It seemed like it was right there, and I felt very privileged to have witnessed such an event," said Kim Johnson, another viewer.
"We live in Loveland and saw a ball (white with a bright green tail) go over the house and it seemed very big and low and I even thought it landed in our 60 acres. Before getting that low, it seemed to go out," said viewer Rosemary Barry. "I have seen falling stars but nothing ever like this one. Pretty strange sighting."
Scientists at the Museum of Nature and Science are looking for people who may have seen it. They're interested in where the meteor was seen, where it possibly landed and if any video or pictures were taken. If you saw the fireball Wednesday night, report your sighting on Cloudbait.com.
Comment: Are these few raindrops the precursors of a more violent storm?
UPDATE: February 25, 2004 Fireball
This bright meteor was widely seen at 6:31 PM MST by residents of Colorado, Wyoming, and Kansas. Over 550 witness reports were received in the first 24 hours. The fireball was captured on six cameras of the DMNS allsky network, allowing excellent identification of its path. [...]
Scientists at Cardiff University, UK, believe they have discovered the cause of crop failures and summer frosts some 1,500 years ago – a comet colliding with Earth.
The team has been studying evidence from tree rings, which suggests that the Earth underwent a series of very cold summers around 536-540 AD, indicating an effect rather like a nuclear winter.
The scientists in the School of Physics and Astronomy believe this was caused by a comet hitting the earth and exploding in the upper atmosphere. The debris from this giant explosion was such that it enveloped the earth in soot and ash, blocking out the sunlight and causing the very cold weather.
This effect is known as a plume and is similar to that which was seen when comet Shoemaker-Levy-9 hit Jupiter in 1995.
Historical references from this period - known as the Dark Ages – are sparse, but what records there are, tell of crop failures and summer frosts.
The work was carried out by two Cardiff undergraduate students, Emma Rigby and Mel Symonds, as part of their student project work under the supervision of Dr Derek Ward-Thompson.
Their findings are reported in the February issue of Astronomy and Geophysics, the in-house magazine of the Royal Astronomical Society.
The surprising result of the new work is just how small a comet is needed to cause such dramatic effects. The scientists calculate that a comet not much more than half a kilometre across could cause a global nuclear winter effect. This is significantly smaller than was previously thought.
Dr. Ward-Thompson said: "One of the exciting aspects of this work is that we have re-classified the size of comet that represents a global threat. This work shows that even a comet of only half a kilometre in size could have global consequences. Previously nothing less than a kilometre across was counted as a global threat. If such an event happened again today, then once again a large fraction of the earth's population could face starvation."
The comet impact caused crop failures and wide-spread starvation among the sixth century population. The timing coincides with the Justinian Plague, widely believed to be the first appearance of the Black Death in Europe. It is possible that the plague was so rampant and took hold so quickly because the population was already weakened by starvation.
Comet disaster throws new light on dark age
By Roger Highfield, Science Editor
The Telegraph
04/02/2004
A monk's apocalyptic book and Arthurian legend are united by a study that shows how a comet plunged Britain into a dark age in the sixth century.
Studies of tree rings showed the Earth underwent a series of very cold summers around 536-540 AD, a Cardiff University team reports in the journal Astronomy and Geophysics. They believe the chill was caused by a comet exploding in the Earth's upper atmosphere.
Historical references from the Dark Ages are sparse, but what records there are tell of crop failures and summer frosts. Gildas Bandonicus, a Celtic monk, in his book Concerning the Ruin of Britain (De Excidio Britanniae) recorded that "the Sun gave forth its light without brightness".
Folklore also suggests that the death of King Arthur - in either 539 or 542 depending on your source - plunged Britain into a dark age. Merlin, Arthur's magician, is depicted in mythology as a "red fiery whooshing dragon flying in the sky" - an account consistent with a comet impact.
Meteorite sparks fears of boat fire
A meteorite may have been the cause of bright light spotted out to sea off the coast of North Otago, which sparked fears a boat was on fire late last night.
At 10.45pm, marine radio advised boat owners a bright orange light had been spotted off the coast of Kakanui, after a witness reported seeing what looked like a boat on fire several kilometres out to sea.
Inspector Warren Kemp, of the Southern Communications Centre, said the light, which was not a flare, was likely to have been caused by a meteorite entering the atmosphere.
"We get reports of this kind of thing from all over New Zealand," he said.
'Paul Revere' scientist suggests unusual asteroid warning system
Just last month, a meteorite slammed into a village in eastern India.
Eleven people were injured and two homes were destroyed by fire.
Perhaps more unsettling, in 1908, a space rock screamed into Earth's atmosphere, exploding in the sky over a remote Siberian forest with a force greater than a 10-megaton nuclear blast.
Fires started, wildlife perished and trees fell for miles in every direction.
These days, efforts underway to detect comets and asteroids on a potential collision course with Earth include an unassuming scientist from Ridgewood, N.J., with an idea for a better method.
William A. Hoffman III doesn't have a company, or investors for his detection system, called "Looking out for you." But he received a patent (U.S. No. 6,452,538), and some distinguished astronomers say his idea is intriguing.
Hoffman wants to place telescopes on the outer-space side of telecommunications satellites where they can continuously scan the heavens, free from cloud cover that often hampers earthbound telescopes, to look for what astronomers call NEOs, or Near Earth Objects.
The data would beam down to a ground station and be sent - for a fee - to schools or institutions or individuals who could use it to pinpoint the rocks' orbit.[...]
Hermes makes its return to Earth
Nov. 10, 2003
BY CAROLE RUTLAND
Special to the Ledger-Enquirer
It is Oct. 28, 1937, and unbeknownst to anyone, a small rocky body is sailing toward Earth in an orbit that comes within 500,000 miles of us. It zooms quickly around the sun and heads back to a place in the great beyond. [...]
We now know that every 777 days, Hermes approaches Earth. Fortunately for us, our planet has always been in another, more distant part of its orbit when Hermes crosses. [...]
Meteors prompt calls to Coast Guard
By Chuck Carroll
Mercury News
Concerned residents from Bodega Bay to San Francisco Bay called the U.S. Coast Guard Sunday night, wondering what the bright lights in the sky might have been.
"They were very determined that it was flares, and so we treated it like it was," said Joe Ford, civilian search and rescue coordinator for the Coast Guard station in San Francisco.
Ford dispatched units to investigate after the calls came in a bunch at about 9:45 p.m.
As it turned out, however, no ships at sea were in trouble. The streaks were nothing more than meteors burning up as they entered the earth's atmosphere from the area of the sky where the constellation Gemini appears.
"It's making its annual pass through the earth's path," Ford said of the shower, known as the Geminids.
Typically, the Geminids provide for a pretty spectacular show, with a good number of relatively large, medium-speed meteors streaking across the sky in a graceful, descending arc.
"If you have not seen a mighty Geminid fireball arcing gracefully across an expanse of sky, then you have not seen a meteor," meteor experts David Levy and Stephen Edberg have written.
Some astronomers believe the Geminids to have been spawned not by a comet, as many are, but by an asteroid that crosses the orbit of Earth, according to Space.com. The Geminids typically peak on Dec. 13 and Dec. 14.
But others believe the shooting stars may be comet debris after all because the asteroid, known as 3200 Phaeton, might be the dead nucleus of a burned-out comet that somehow got trapped into an unusually tight orbit, Space.com reported.
While the peak has passed, sky-watchers say it pays off to keep looking for the next week or so, as some of the brightest fireballs of Geminids tend to be stragglers.
Space probe sweeps up comet dust02/01/2004
An American space probe has entered the shimmering tail of a comet and is collecting hundreds of dust particles which will be returned to Earth for analysis.
The National Aeronautics and Space Administration says its Stardust spacecraft will pass within 186 miles of the comet Wild 2 as it flies through the gossamer cloud that envelops the dirty ball of ice and rock. [...]
Comets spread Earth-life around galaxy, say scientists
If comets hitting the Earth could cause ecological disasters, including extinctions of species and climate change, they could also disperse Earth-life to the most distant parts of the Galaxy. [...]
Earth At Risk: New Calls For Planetary Defense
By Leonard David
Senior Space Writer
GARDEN GROVE, California – It is past time to get serious about planetary defense, experts say. The threat of Earth being on the receiving end of a cosmic calling card in the form of an asteroid or comet is real.
Despite increasing scientific agreement regarding the danger posed by near-Earth objects smashing into our planet, governmental steps to deal with the issue are missing-in-action. At present, only patchwork and under-funded research efforts are underway to robustly detect, track, catalog and plot out strategies to thwart menacing asteroids and comets that place Earth at risk.
First Strike or Asteroid Impact? The Urgent Need to Know the Difference An international confab of experts is taking part in The Planetary Defense Conference: Protecting Earth from Asteroids here this week and sponsored by The Aerospace Corporation and the American Institute of Aeronautics and Astronautics (AIAA).
The four-days of discussion were kicked off by Congressman Dana Rohrabacher, Chairman of the House Science Committee's Space and Aeronautics Subcommittee
Rohrabacher noted that it took the attacks of Sept. 11 for the country to focus on global terrorism. "I hope that it won’t take that type of catastrophe for us to start paying attention to the threats of near-Earth objects," he said.
The lawmaker said the political reaction to the worries over space rocks has garnered "a very tepid response" to date, noting that money spent so far on the issue has been "a pittance."
President George W. Bush’s new visionary blueprint for NASA – including a human return to the Moon and sending astronauts to Mars – was saluted by Rohrabacher. That plan, he added, can also support planetary defense objectives.
"The Moon could well be a base of operations that we could use as a means to defend this planet in a timely way, and a more effective way, against near Earth objects," Rohrabacher explained.
Taking a "let’s get going," roll-up-your sleeves attitude, Rohrabacher said there is need to start now in readying the technologies necessary to deflect an Earth-threatening object. "What we need to do is build from right here…this moment. The people in this room can save the planet."
Warning time
There is no question that an asteroid has Earth’s name on it, astronomers agree. But where the rock is and when that impact is going to occur is unknown, said David Morrison of the NASA Astrobiology Institute at the space agency’s Ames Research Center at Moffett Field, California.
NASA now supports -- in collaboration with the United States Air Force -- the Spaceguard Survey and its goal of discovering and tracking 90 percent of the Near Earth Asteroids (NEAs) with a diameter greater than about one-half mile (1 kilometer) by 2008. If one of these big bruisers were to strike our planet, it would spark catastrophic global effects that would include severe regional devastation and global climate change.
By charting the whereabouts of these celestial objects, it is anticipated that decades of warning time is likely if one of the large-sized space boulders was found to be on a heading that intersects Earth.
But a uniform message from the experts attending this week’s planetary defense gathering is extending the survey to spot smaller objects, down to some 500 feet (150 meters) in diameter. These asteroids can wreak havoc too, but on a more localized scale.
For instance, if one of these smaller asteroids were to strike along the California coast, millions of people might be killed, Morrison said. A little further to the east, he added, "a nice crater out in the desert" would become a tourist attraction.
In identifying ways to deal with hazardous asteroids, a first order of business is gaining a better understanding of the enemy. That is, are they fluffy stuff, constituting a rubble pile, or are they tough-as-nails slabs of iron? Along with these physical properties, astronomers want to know more about their overall shape, rotation rate, and whether an object might play host to a smaller companion body.
Developing a robust deflection scheme so an asteroid doesn’t hit Earth means taking into account these factors and a host of other issues, said Don Yeomans, a leading asteroid and comet scientist at the Jet Propulsion Laboratory (JPL) in Pasadena, California.
Developing a viable mitigation campaign, Yeomans explained, demands three prerequisites: "You need to find them early. You need to find them early. And we need to find them early."
Friendly-fire
Now being discussed is a way to flex, test, and calibrate present day computer and hardware tools to first detect and then keep a trained eye on a potential Earth impactor.
There are currently three Earth-impactors en route. But don’t worry. It’s all friendly fire.
NASA’s Genesis spacecraft is headed this way in September of this year. So too is the Stardust spacecraft in January 2006, as will be a Japanese asteroid sample mission in June 2007. All three are designed to reenter the Earth’s atmosphere and touch down on terra firma, each carrying a precious cargo of scooped-up specimens.
"So we do have current impactors coming back," Yeomans said. While still in the preliminary discussion stage, the idea is to use these incoming spacecraft to shake out coordinated observations, sharpen orbit calculation skills, and help fine-tune procedures now in place for detecting and tracking asteroids and comets, he told SPACE.com .
Yeomans said about 40 objects at least 3 feet (1 meter) in size enter the Earth’s atmosphere every year. Some of these incoming objects have been observed by space-based infrared and visible sensors and other ground-based detection devices operated by the U.S. military and other government agencies, he said.
"They have indeed made many of these observations available to scientific investigators," Yeomans said. "It would be nicer to get these things [the data] a little more quickly than 3-4 months down the road,’ he added, with near-simultaneous flow of information about such events seen as ideal.
Largest meteorite fall
Space and ground sensors proved useful last year in studying a major meteor explosion in Earth’s atmosphere. The event also brought home the point of how a natural event can take on the guise of a human-made terrorist act.
Dee Pack, Director of The Aerospace Corporation’s Remote Sensing Department, detailed a large-scale meteorite fall that occurred over Park Forest, Illinois on March 27, 2003.
"This is the largest meteorite fall over a densely populated area in modern history," Pack and a team of fellow specialists reported at the meeting. The initial mass of the object is now estimated to be nearly 8 tons.
The explosion took place at nearly midnight local time. Fragments of the airbursting meteorite cut through several roofs. The explosive disintegration of the object lit up the night sky to daylight levels. Sonic booms were heard over a wide area. Numbers of meteorites resulting from the event were recovered, later classified as bits of a stony space rock.
Making it all the more jittery for those folks in the fall zone, the object exploded during Operation Iraqi Freedom, with many witnesses worried this natural event was some kind of massive explosion or nuclear event.
Pack and his colleagues contend: "These large meteors, or superbolides, are of concern to the Department of Defense due to their ability to mimic nuclear events." This type of extraordinary Earth-crossing object serves to train global observers to better recognize and characterize these naturally occurring huge explosive events.
Who do you call?
A clear and present danger for those studying planetary defense is the lack of any chain-of-command to take on the duties of dealing with the prospect of disruptive collisions from asteroids and comets.
This "who do you call?" factor deserves immediate attention, said Michael Belton of Belton Space Exploration Initiatives in Tucson, Arizona.
Belton detailed the findings of a NASA-sponsored 2002 workshop. It brought together over 75 top scientists, engineers and military experts from the United States, Europe, and Japan to review the science behind mitigating hazardous comets and asteroids.
A central finding: There is lack of any assigned responsibility to any national or international governmental organization to prepare for a disruptive collision. There is absence of any authority to act in preparation for some future collision-mitigation attempt, Belton said.
The 2002 workshop did recommend that NASA be assigned the duty to advance work in beefing up the science and ability to respond to an imminent collision with an asteroid or comet nucleus. Furthermore, the now-in progress Spaceguard Survey should be extended to scope out possible impactors down to 655 feet (200 meters) in size.
In addition, Belton said that there is need for the Defense Department to more rapidly communicate surveillance data on natural airbursts. And lastly, there’s need for governmental policy makers to formulate a chain of responsibility for action in the event a threat to the Earth becomes known.
"In other words…there isn’t anybody to call. There is nobody there. And there’s nobody with authority…nobody with any resources," Belton said. "And we need to correct that.
A naked-eye comet - one visible to the unaided eye without telescope or binoculars - is an enjoyable sight, particularly for the brighter comets. On average, a naked-eye comet graces our skies about once every two years.
However, most remain fairly faint or appear close to the Sun as seen from Earth, such that even experienced observers may require binoculars to spot them. Only rarely do two relatively bright naked-eye comets appear simultaneously. Such an event will take place in April and May of 2004, when skygazers will feast their eyes upon both Comets.[...]
Scientists are interested in comets for a number of reasons. "Comets are thought to have formed in the outer reaches of the solar system, and may thus contain rock and ices that date back billions of years. Also, comet tails are indicators of the solar wind and have helped us learn about the inner solar system. And not least, comets are known to hit planets from time to time, including Earth, so we need to keep an eye out for potential impactors," said Green. [...]
"Comets do a lot of things that are unpredictable," said Green. [...]
As June opens, both comets will fade as they speed ever farther from both the Sun and the Earth. Yet if current predictions hold, the brief but enjoyable appearances of Comet NEAT and Comet LINEAR will be remembered for years to come!
Atlanta firm envisions defending Earth with army of nuclear-powered robots
By MIKE TONER
The Atlanta Journal-Constitution
Published on: 02/20/04
A killer asteroid, the kind of space rock that did in the dinosaurs, is on a collision course with Earth. A fleet of nuclear-powered robots races to the rescue. Humanity's survival hangs in the balance.
By the second bag of popcorn, swarms of robotic MADMEN — short for Modular Asteroid Deflection Mission Ejector Nodes — are descending on the doomsday rock. They attack like hungry dragonflies, gouging out chunks and hurling them into space with such force that the asteroid is slowly nudged into a new trajectory. The shift averts the ultimate catastrophe. The human race survives.
Hollywood has been spinning out variations of the theme for years in films like "Armageddon," "Deep Impact," "Fire From the Sky," "Meteor" and "Asteroid." Now, in a gleaming glass office building near Atlanta's Perimeter Mall, a small technology company is taking some of the fiction out of science fiction and proving that, sometimes, science is even stranger than fiction.
Inconspicuous in a building occupied by corporate tenants like H&R Block, Starwood Hotels and Target Stores, a handful of real-life engineers is pondering the defense of Planet Earth. Under a $75,000 NASA contract — less than a movie studio would pay for a good sci-fi script — SpaceWorks Engineering Inc. is studying one way the world might someday avert astrophysical Armageddon.
No one at the firm, founded by Georgia Tech aerospace engineering professor John Olds and staffed entirely by Georgia Tech graduates, has illusions that hordes of their MADMEN robots are going to be racing to humanity's rescue anytime soon.
Their study is purely a conceptual exercise. Like an architect's preliminary renderings of a new building, it will provide a few pretty pictures, a paper report and food for thought. If feasible, a defense of the planet would require decades to develop and cost tens of billions of dollars.
But given the near certainty that an asteroid will strike the Earth at some time in the indefinite future, Olds says, it makes sense to think now about ways such a catastrophe might be prevented.[...]
"When it comes to planetary defense, there are really two basic questions," Olds says. "Is something going to hit us? And what are we going to do about it? It's like insurance. If we wait until we answer the first question, it may be too late to do anything about it."
NASA is making progress on the first question. Over the last decade, ground-based telescopes have identified 2,672 "near-earth objects," whose orbits bring them in the general vicinity of Earth.
One of the latest found, minor planet 2004 CZ1, is a 150-foot-wide space rock that is due Tuesday to pass within 3.8 million miles of Earth — a virtual hair's breadth in the vastness of space.
By 2008, the NASA-led international Space Guard Survey hopes to have identified the orbits of 90 percent of the largest objects — a kilometer (0.6 mile) or more in diameter — that could pose a threat. Any object that large that struck the Earth would cause a planetary catastrophe.
The chances of that happening are one in a half-million years, according to one NASA report. But astronomers say there may be a million smaller rocks careening around the solar system, sufficient to wipe out a large city. The chances of such an impact are estimated at one in 1,000 years.
"It can happen," says Olds. "Just look at Tunguska."
In 1908, what is believed to have been a meteorite or comet exploded three miles above the Tunguska River Valley in Siberia with the force of 1,000 Hiroshima atomic bombs. Because the area was so remote, populated primarily by reindeer herders, casualties are unknown. The blast leveled 800 square miles of forest, felling trees like toothpicks and knocking people to the ground 40 miles away.
The blast wave from the explosion was detected by weather stations as far away as Berlin and the "salmon pink" glow of the fireball was visible in the night sky in London. The Tunguska object is thought to have been less than 200 feet in diameter. Scientists say a similar event on the U.S. East Coast today could easily kill 1 million people.
Over the years, in and out of Hollywood, a number of ideas for deflecting or destroying a doomsday asteroid have been proposed: blasting it into fragments or hitching up a massive engine that would divert it from a collision course with Earth.
The promise and pitfalls of a variety of schemes are on the agenda this month at the American Institute of Aeronautics and Astronautics' Planetary Defense Conference in Orange County, Calif. Scenarios to be considered include the threat of a 360-foot-wide asteroid destined to hit Europe, a comet aimed at the Mississippi Valley and a small asteroid headed for the Pacific Ocean 200 miles off the California coast.
Traditional concepts for intercepting and neutralizing the threat of an incoming asteroid or comet are fraught with problems.
Breaking up an asteroid without changing its trajectory would simply cause Earth to get smacked by smaller fragments. And changing the trajectory would require delivering and assembling an engine powerful enough to move a body the size of a football stadium — impractical with today's technology.
A.C. Charania, SpaceWorks' "senior futurist," says one possible key to an effective planetary defense may lie in numbers, not in sheer might. The concept invokes Newton's Third Law of Motion –- "for every action, there is an equal and opposite reaction."
An astronaut standing on a doomsday asteroid could, in theory, deflect its path by a miniscule amount simply by throwing a chunk of it into space. Unless he threw a lot of pieces very fast, however, he wouldn't alter the asteroid's course by much.
But Charania says thousands of nuclear-powered robots, working like an army of futuristic tennis ball machines, could launch into space enough of the offending rock, piecemeal, to shift its course by thousands of miles.
Olds says the robotic mass ejectors would be manufactured and stored in space until a threatening asteroid appeared. Then, they would intercept it, land, drill into the surface and use a conveyor-type system to hurl chunks of the asteroid into space. [...]
"Our hope is that projects such as ours can concretely lead to better detection systems and mitigation plans to show the extent of the threat and that something can be done against it," he says.
The strange summer of 1783 saw an almost unprecedented number of fireballs and lightning strikes throughout England. In London alone, more than 16 people were killed and many houses destroyed. In the same period,a curious low-flying meteor exploded over south-eastern England. Nick Rawlinson ponders this exceedingly fortean coincidence.
Comment: A very entertaining article with some of the stranger fireball incidents recorded such as:
In 1256 a ‘comet’ coincided with exceptional high tides and storms, and “a great sound was heard in sundry parts of England, as if a mighty mountain had fallen into the sea.” Noisy meteors, note Knight and WG, also followed tremendous thunderstorms in Italy in 570 and in Constantinople in 611, with fatal incidences of ball lightning. On both occasions, the inhabitants were visited by two ‘humanoid creatures" and were afflicted with a spate of “deformed births” for months afterwards. In France, in the reign of King Gunthran, a fireball fell onto the city of Bordeaux, consuming it with fire and leaving a strange pestilence (a “cough and bloody flux”) in its wake.
How Asteroids Trigger Volcanos
space.com
[...] Now a comprehensive review of evidence provides more support for one aspect of the idea, that impacts beget serious volcanism.
Dallas Abbott of the Lamont-Doherty Earth Institute and Ann Isley from the State University of New York at Oswego examined existing impact data going back 4 billion years.
They found 10 major peaks in activity -- stretches of time when asteroids and comets hit the planet in relative flurries. During nine of the 10 peaks, volcanic activity also peaked, as measured by evidence of magma from deep inside Earth, in the mantle, flowing to the surface. Further, two prominent lulls in impact activity also matched up with periods of decreased volcanism. [...]
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