Youtube Wed, 04 Jul 2007 08:07 EDT
Investigations of a buried layer at sites from California to Belgium reveal materials that include metallic microspherules, carbon spherules, nanodiamonds, fullerenes, charcoal, and soot. The layer's composition may indicate that a massive body, possibly a comet, exploded in the atmosphere over the Laurentide Ice Sheet 12,900 years ago. The timing coincides with a great die-off of mammoths and other North American megafauna and the onset of a period of cooling in Northern Europe and elswhere known as the Younger Dryas Event. The American Clovis culture appears to have been dramatically affected, even terminated, at this same time. Speakers discuss numerous lines of evidence contributing to the impact hypothesis. The nature and frequency of this new kind of impact event could have major implications for our understanding of extinctions and climate change.
Part 1
This news conference is a watershed event for climate research. It's been a long journey from the derision heaped upon Immanuel Velikovsky in the 1950's through the 1980's when Carl Sagan famously ridiculed his cometary thesis in the PBS series Cosmos.
New research since even when the abstracts were published prior to the AGU meeting include the discovery of nanodiamonds in the layer just below the Black Mat in the deposits analyzed around North America and Belgium which can only come from a extraterrestrial impact. Here, scientists question "Just what roll impacts play with climate." And discuss the ice core evidence from Greenland and Antarctica: "There's strong evidence of massive biosphere burning." They conclude that the Younger Dryas "cooling would not have occurred without the impact."
For more information read the SOTT Focus article, The Younger Dryas Impact Event and the Cycles of Cosmic Catastrophes - Climate Scientists Awakening.
Parts 2
Part 3
Part 4
Part 5
Part 6
Part 7
Science Daily Fri, 06 Jul 2007 17:38 EDT
Researchers at the University of Southampton have developed a software package for modelling asteroid impacts that enables them to assess the potential human and economic consequences across the globe.
The software, called NEOimpactor, has been specifically developed for measuring the impact of 'small' asteroids under one kilometre in diameter, and early results indicate that the ten countries most at risk are China, Indonesia, India, Japan, the United States, the Philippines, Italy, the United Kingdom, Brazil and Nigeria.
'The threat of the Earth being hit by an asteroid is increasingly being accepted as the single greatest natural disaster hazard faced by humanity,' comments Nick Bailey of the University of Southampton's School of Engineering Sciences, who developed the software with University colleague Dr Graham Swinerd, and Dr Richard Crowther of the Rutherford Appleton Laboratory .
'Since 1998 the international Spaceguard survey has been cataloguing all near earth asteroids (NEA) larger than one kilometre in diameter. However, small asteroids, under one kilometre in diameter, remain predominantly undetected. While the direct consequences might not be quite as extreme, these small objects exist in far greater numbers and therefore will impact more frequently. It is on these sub-kilometre asteroid impacts that we have been focusing to assess the consequences for both humans and for infrastructure across the globe.'
Initial investigations have examined how the consequences of an impact change with increasing impact energy. Taking a spherical stony asteroid travelling at 12,000 miles per second and varying the diameter to increase kinetic energy, the results indicate that a 100 metre diameter asteroid will predominantly cause localised casualties and damage across a few countries when impacting on either land or ocean. However, the consequences of a 200 metre diameter asteroid hitting the ocean increase significantly, with the generated tsunamis reaching a global scale. At 500 metres in diameter, almost any ocean impact will generate significant casualties and economic cost across the world.
The team used the raw data from the multiple impact simulations to rank each country based on the number of times and how severely they would be affected by each impact. Early results show that in terms of population lost, China, Indonesia, India, Japan and the United States face the greatest overall threat; while the United States, China, Sweden, Canada and Japan face the most severe economic effects due to the infrastructure destroyed.
In both rankings, the United Kingdom appears eighth in the list of countries most affected. Of the top twenty for each ranking, over half the countries appear in both lists.
'The consequences for human populations and infrastructure as a result of an impact are enormous,' continues Nick Bailey. 'Nearly one hundred years ago a remote region near the Tunguska River witnessed the largest asteroid impact event in living memory when a relatively small object (approximately 50 metres in diameter) exploded in mid-air. While it only flattened unpopulated forest, had it exploded over London it could have devastated everything within the M25.
'Our results highlight those countries that face the greatest risk from this most global of natural hazards and thus indicate which nations need to be involved in mitigating the threat.'
Note: This story has been adapted from a news release issued by University of Southampton.
Univ. of South Carolina Thu, 05 Jul 2007 22:43 EDT
A comet theory put forth by a group of 25 geo-scientists suggests that a massive comet exploded over Canada, possibly wiping out both beast and man around 12,900 years ago, and pushing the earth into another ice age.
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| ©USC |
| Site where most pre-Clovis work is being done. |
University of South Carolina archaeologist Dr. Albert Goodyear said the theory may not be such "out-of-this-world" thinking based on his study of ancient stone-tool artifacts he and his team have excavated from the Topper dig site in Allendale, as well as ones found in Georgia, North Carolina and Virginia.
The tools, or fluted spear points, made by flaking and chipping flint, were used for hunting and made by the Clovis people, who lived 13,100 to 12,900 years ago, and from the Redstone people who emerged afterwards. The two points are distinctly different in appearance, with Redstone points more impressively long and steeple-shaped.
"I saw a tremendous drop off of Redstone points after Clovis," said Goodyear. "When you see such a widespread decline or pattern like that, you really have to wonder whether there is a population decline to go with it."
For every Redstone point, Goodyear says, there are four or five Clovis points. His findings are leading archaeologists from across North America to reexamine their fluted points, and their inventories are yielding similar results: a widespread decline of post-Clovis points that suggests a possible widespread decline of humans.
"What is interesting is that Redstone people came after Clovis people and may have lasted as many centuries as Clovis did, probably even longer, but there are fewer of these Redstone points than Clovis ones," Goodyear said. "That is really odd, because if the Redstone culture simply came right after the Clovis culture you'd expect at least as many Redstone points as Clovis ones. We just don't see that, and the question is why, and what happened to the people who made these tools?"
Archaeologists have long known that the great beasts of the age - the wooly mammoth and mastodon - suddenly disappeared around the same time period (12,900 - 12, 800 years ), but little was known about their demise. It was thought to be the result of over-hunting by Clovis man or climate change associated with a new ice age.
The notion that a comet collided with Earth and caused these events was farfetched until recently, when the group of scientists began looking for evidence of a comet impact, which they call the Younger - Dryas Event. They turned to Goodyear and the pristine Clovis site of Topper.
In 2005, Arizona geophysicist Dr. Allen West and his team traveled to Topper in hopes of finding concentrations of iridium, an extra-terrestrial element found in comets, in the layer of Clovis-era sediment.
"They found iridium and plenty of it," said Goodyear. "The high concentrations were much higher than you would normally see in the background of the earth's crust. That tends to be an indicator of a terrestrial impact from outer space."
The researchers also found high iridium concentrations at six other Clovis sites throughout North America, as well as in and along the rims of the Carolina Bays, the elliptically shaped depressions that are home to an array of flora and fauna along South Carolina's coast.
The Younger- Dryas Event suggests that a large comet exploded above Canada, creating a storm of fiery fragments that rained over North America. The fragments could have easily killed the giant mammals of the day, as well as Clovis man.
"No one has ever had a really good explanation for the disappearance of mammoth and mastodon," Goodyear said. "The archaeological community is waking up to the Younger-Dryas Event. It doesn't prove that these Clovis people were affected by this comet, but it is consistent with the idea that something catastrophic happened to the Clovis people at the same time period."
The comet theory dominated the recent annual meetings of the American Geophysical Union held in Mexico. Goodyear's Clovis-Redstone point study and West's research on the comet were featured at the AGU meetings and by the journal, Nature. The comet will be the subject of documentaries featured on the National Geographic Channel and NOVA television late this fall and in early 2008.
The Topper story
Dr. Al Goodyear, who conducts research through the University of South Carolina's S.C. Institute of Anthropology and Archaeology, began excavating Clovis artifacts along the Savannah River in Allendale County in 1984. In 1998, with the hope of finding evidence of a pre-Clovis culture earlier than the accepted 13,100 years, Goodyear began a concerted digging effort on a site called Topper, located on the property of the Clariant Co.
His efforts paid off. Goodyear unearthed blades made of flint and chert that he believed to be the tools of an ice age culture back some 16,000 years or more. His findings, as well as similar ones yielded at other pre-Clovis sites in North America, sparked great change and debate in the scientific community.
Believing that if Clovis and Redstone people thrived near the banks of the Savannah River, Goodyear thought the area could haven been an ideal location for a more ancient culture. Acting on a hunch in 2004, Goodyear dug even deeper down into the Pleistocene Terrace and found more artifacts of a pre-Clovis type buried in a layer of sediment stained with charcoal deposits. Radio carbon dates of the burnt plant remains yielded dates of 50,000 years, which suggested man was in South Carolina long before the last ice age. Goodyear's finding not only captured international media attention, but it has put the archaeology field in flux, opening scientific minds to the possibility of an even earlier pre-Clovis occupation of the Americas.
Since 2004, Goodyear has continued his Clovis and pre-Clovis excavations at Topper. With support of Clariant Corp. and SCANA, plus numerous individual donors, a massive shelter and viewing deck now sit above the dig site to allow Goodyear and his team of graduate students and community volunteers to dig free from the heat and rain and to protect what may be the most significant early-man dig in America.
WHDH-TV Sat, 07 Jul 2007 22:33 EDT
WOBURN, Mass. -- Experts say the rock-like object that fell from the sky in Woburn is not a meteorite.
However, they say the item probably is something from space and is radioactive.
The object came crashing through the roof of a warehouse in Woburn last week.
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| ©WHDH-TV |
Experts said they should definitely know what it is by the end of the month.
Comment: Not a meteorite - probably is something from space? What explanation are they going to come up with this time?
Herts and Essex News Sun, 08 Jul 2007 07:33 EDT
AN orange ball and lights in the sky has left a Cheshunt man wondering if aliens really do exist.
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| ©Paul Adams |
| UFO Over Cheshunt |
His friends have suggested extraterrestrials could be behind the drama although Paul, of Pengelly Close, is slightly more sceptical.
Paul had been watching films at about 3am on Wednesday last week when he decided to go outside for a cigarette.
"I saw this orange ball that got bigger," he recounted.
"Within five seconds, it's right over the top of the house. Three lines went straight up but there was no noise. It lit the sky up.
"I've gone to take another photo on my phone and it's gone."
Paul added: "I did think this is gorgeous. It was beautiful, really nice.
"But it was very strange. I've never seen anything like that. It wasn't lightning and it wasn't fireworks."
So do these photos show an alien spacecraft looking to land in the Lee Valley?
"My mates had a good laugh and said it could be a UFO," said Paul.
"However I believe in my daughter and I believe in my wife and that's about it."
UFO seen above Hungerford...againMiles Amoore Newbury Weekly News Wed, 11 Jul 2007 11:29 EDT
Taxi driver spots orange shapes in sky over Hungerford and man sees UFO the size of four football pitches above Thatcham
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| ©Newbury News |
MORE reports of UFO sightings in the summer skies above West Berkshire have left people baffled.
A Swindon taxi driver recently added to the growing list of supernatural occurrences spotted by locals in the district.
Having just dropped off a fare in Hungerford, Neil Whitby spotted four bright orange shapes in the sky.
Drifting silently across the sky at what he believed was a fairly low altitude, the lights began to flicker before suddenly disappearing.
A few weeks earlier, a man from Newbury rang the Newbury Weekly News claiming to have spotted circles in the sky the size of four football pitches hovering above Henwick Fields in Thatcham for five minutes. He said his son had also seen the lights.
The inexplicable phenomena are the latest in a whole string of local UFO sightings dating as far back as 1909, when an organist from St Michael's Church in Lambourn spotted a shape coming from the East that he said intermittently let off loud explosions.
UFO expert Steve Harris of the Newbury Amateur Astronomical Society said: "I have actually seen spacecraft returning to earth before. When you see things that are glowing as they go through the atmosphere it is generally spacecraft or space junk."
LITTLE green men, cigar-shaped metal objects travelling at supersonic speeds, or balls of fire rising from the earth. West Berkshire has had its fair share of UFO sightings.
Three years ago locals in Hungerford were left baffled by a giant fireball attached to a solid cigar-shaped structure (pictured above), which some saw plummet to earth before rising into the night sky again.
People said pets were behaving strangely twenty minutes before the fireball appeared and police even dispatched helicopters to look for debris while firefighters scoured the area in search of a point of impact.
UFO experts from America, who were holidaying in Marlborough at the time, became so excited by the sighting that they set up camp near Hungerford to await the fireball's return.
The mystery was never explained and a man even saw a similar ball of flame above Thatcham a year later.
In September 2006, a triangular-shaped formation of glowing lights was seen drifting across the sky above Greenham Common (see additional pictures).
Some witnesses said the lights formed a V shaped formation, hovering over the common for three minutes before disappearing into the night sky at lightning speed.
The MOD and Met office were left scratching their heads, unable to explain the Greenham sightings or the power cuts and bright flashes that accompanied them.
At the time, UFO expert Steve Harris dismissed satellites, meteors and space junk as possible explanations, It seemed to come straight through the window and into my head...it was very painful as these would only light up the sky for a couple of seconds. He said: "We would have to put it down as an unidentified flying object."
WEST Berkshire's catalogue of UFO sightings coincides with an age when rumours of alien autopsies abounded.
In the summer of 1968, a Newbury man was drawing his curtains when a huge circular object flashed across the horizon at break-neck speed. On the same evening, two policemen in Kent spotted an object of a similar description also travelling abnormally fast.
Fifteen years earlier the same man spotted a large cigar-shaped object moving through the sky while he was walking his dog in Love Lane.
In 1971, after two sightings, the man was so impressed that he founded the Newbury-based South-West Aerial Phenomena Society (SWAPS), members of which made it their mission to record and investigate UFO sightings in West Berkshire.
One of the club's first investigations into the bizarre night time phenomena was to set up a "skywatch" to chart the movement of orange lights seen by people in May 1972.
SWAPS sent investigators to the home of Wickham actress Coral Atkins, who had told the Newbury Weekly News: "I saw a ball of orangey white light coming towards me. It seemed to come straight through the window and into my head.
"It was very painful but for a few seconds it seemed as if I was standing back from the world and I could see everything as it should be."
The next recorded sightings occurred in February 1972 when two UFOs were spotted above Kintbury and Brightwalton on the same night.
Witnesses who chased the mysterious oval-shaped objects on scooters until they vanished into the night sky said the UFOs had beams of light radiating from them and red diodes flashing sporadically.
ONE of the few sightings that has actually been explained occurred on Christmas Day in 1980 when a UFO scare had dozens of people all over the district claiming they had seen alien activity.
In fact, it later became clear that the bright lights in the sky were simply a Russian rocket breaking up as it re-entered the atmosphere.
Mr Harris said that, while unidentified flying objects are common, he did not believe they were part of an extra-terrestrial mission to take over the earth.
He said: ""Interstella travel - just travelling from one star system to another - is a million times more difficult than travelling to the moon.
"When you consider that the nearest star is four and a half light years away, it seems a long way to come just to hover over Greenham Common and not make contact with us.
"Most if not all sightings are explainable, whether they are military helicopters or telecommunications satellites."
Matthew C. Durkee Victorville Daily Press Wed, 11 Jul 2007 08:46 EDT
EDWARDS AFB - If your house shakes and you hear a mysterious boom during the next nine days, look up.
NASA's Dryden Flight Research Center will be experimenting with sonic booms today through July 20 to assess the impact on modern housing construction.
Called the Housing Structural Response to Sonic Booms Test, the experiment consists of an F-18 research aircraft flying at supersonic speeds to subject an Edwards base house to sonic booms.
Engineers from NASA's Langley Research Center in Hampton, Va., will operate more than 100 sensors inside and outside the house to measure both pressure and vibration.
Dryden officials say the sonic booms will be focused away from surrounding communities, but they are notifying the public that there will be up to six sonic booms on each mission, six minutes apart. No more than two missions will be flown on one day, officials said.
The purpose of the experiment is to find ways to make overland supersonic travel possible.
Since the 1950s engineers have tried but failed to achieve supersonic flight with low-impact sonic booms. As a result, the usefulness of supersonic flight outside of military purposes has been severely restricted.
The Concorde was one of only two supersonic passenger jet designs ever operated, and it flew only transoceanic flights so that the sonic booms would not disturb anyone. Concorde flights ended in 2003.
NASA officials have been studying ways to mitigate sonic booms throughout the past decade.
Noise-related questions should be forwarded to Air Force Flight Test Center public affairs at (661) 277 -3517.
Matthew C. Durkee may be reached at 951-6226 or mdurkee@vvdailypress.com.
Blake Jones The Garden Island Mon, 09 Jul 2007 22:04 EDT
Kauai - An explosion that has yet to be explained was heard and felt in Lihu'e Sunday night between 8:30 and 9:30, according to witnesses.
County Public Information Officer Mary Daubert said a police officer did check out the area in response to calls but was not able to determine the cause.
Police Commissioner Tom Iannucci, who was waiting with his kids at the Lihu'e Taco Bell drive-through, said there was no mistaking the noise and "slight concussion" to the car, which he likened to a dynamite explosion.
"Being a former Marine who served in a war zone, Beirut, I know exactly what it was," Iannucci said.
Iannucci called 911 to report the blast and was told by the dispatch operator that there had been other calls about an explosion in the area.
"It was too large to be something simple," he noted, adding that he did not see anything, smoke or otherwise. "To ... hear it as loud as I heard it and feel the slight jolt in the vehicle, something happened."
Don Uohara was relaying cables with a Wasa Electrical Services crew at the stop light at Kaumuali'i Highway and Nawiliwili Road when he, too, heard a "pretty loud" boom.
"We turned around and said, 'What was that?'" Uohara said of his and coworkers' reactions.
Kauai Film Commissioner Art Umezu said he did not know of any pyrotechnics that took place in the area for the film "Tropic Thunder," which is being produced on-island. The movie follows actors shooting a war flick who become their characters after a strange series of events.
"They don't believe they've done anything, especially on a Sunday," Umezu said after talking to the film's production office.
According to Capt. David Bukoski of the Fire Prevention Bureau, there have been explosions and testing in the past for the film, but nothing was scheduled or permitted for Sunday.
Bukowski said the Fire Department has a good relationship with the certified and licensed pyrotechnicians.
"They are very cognizant of the public," Bukoski said of the crew.
Space.com / AP Mon, 16 Jul 2007 13:03 EDT
A forest fire has led to a chance discovery of debris from the impact of a meteorite 1.85 billion years ago, more than 450 miles away at Sudbury, Ontario.
Geologists had scheduled a field trip in May along the Gunflint Trail in northeastern Minnesota, but most areas they wanted to explore were closed because of a wildfire that charred more than 118 square miles.
Geologist Mark Jirsa of the Minnesota Geological Survey went up the trail to scout new locations and, in a spot he had never visited before, stumbled across debris now linked to the Sudbury impact.
That impact created a crater more than 150 miles across, scattering rock and dust over nearly a million square miles.
"It's fairly dark rock,'' Jirsa said. "They look like concrete, but in this concrete you would throw pieces of rock of all sizes and shapes and in all possible orientations.''
Previously, material thrown out by the impact had been found as far from Sudbury as Hibbing, about 125 miles farther to the southwest from Grand Marais. However, the tiny fragments at Hibbing were found in core samples from 800 to 1,000 feet below the surface, while the rock layer containing larger chunks at the Gunflint site lies exposed.
"I think the excitement for the people of Minnesota is that we are one place in the world where you can see evidence of an ancient meteorite impact,'' said University of Minnesota geology professor emeritus Paul Weiblen, who is studying the debris. "This is the second-oldest and second-largest impact crater in the world.''
Denis St. Pierre The Sudbury Star Tue, 17 Jul 2007 12:36 EDT
A Laurentian University geologist says he is intrigued, but skeptical of a report that rock from the meteorite that created the Sudbury basin has been found 700 kilometres away in the United States.
Andrew McDonald, a geologist and professor in Laurentian's department of earth sciences, said he was surprised by Monday's report of the findings of a Minnesota geologist.
Geologist Mark Jirsa of the Minnesota Geological Survey reported he discovered the Sudbury-related rock along the Gunflint Trail in northeastern Minnesota.
Jirsa said he found an exposed rock layer containing large chunks of what he determined is debris from the meteorite impact that created the Sudbury basin 1.85 billion years ago.
"It's fairly dark rock," Jirsa told the Associated Press. "They look like concrete, but in this concrete you would (see) pieces of rock of all sizes and shapes and in all possible orientations."
The finding was made in May and was followed by weeks of analysis.
"I think the excitement for the people of Minnesota is that we are one place in the world where you can see evidence of an ancient meteorite impact," said University of Minnesota geology professor emeritus Paul Weiblen, who is studying the debris.
"This is the second-oldest and second-largest impact crater in the world," Weiblen told the AP.
McDonald said he was anxious to investigate the report, adding he would be shocked if rock from the Sudbury meteorite landed 700 kilometres away.
"With the distance to that particular site, a surface exposure of something like this might be a little dicey," McDonald said. "That's a good distance."
The so-called Sudbury breccia, the mineralized rock deposited by the meteorite, "has been found up to 60 kilometres outside Sudbury, but I'm not familiar with it being found that far away," he said.
Still McDonald said he could not absolutely discount the report from Minnesota.
"Not knowing what they've got, or how they're making the link to Sudbury, it's very difficult to say if what they have is truly related to Sudbury," he said.
"There are a lot of things that basically rely on interpretation and what one person sees is not necessarily what another person sees. So I'm not saying these fellows are wrong or they've done something incorrectly, I'm just saying the interpretation they make might not be the one other people would make, in which case it may be more debatable as to what they've actually got."
The rock found in Minnesota could be "something like a Sudbury breccia," he added.
If the Minnesota report is authenticated, "it would be a reflection of how explosive or energetic the impact was" from the Sudbury meteorite, McDonald said.
"But 700 kilometres is pretty darn far. If you think about it, you have material that is being thrown that kind of a distance. That would be quite remarkable in terms of the energy that would have been released from the impact of the meteorite.
"But I suppose if this is in fact something related to the Sudbury impact, it would clearly illustrate the enormity of the energy that was released by this impact."
The Sudbury basin is about 60 kilometres long and 30 kilometres wide. The basin is believed to be a small portion of a crater 240 kilometres in diameter created by the meteorite. As such, the crater would be second in size only to the Vredefort crater in South Africa, which has a diameter of about 300 kilometres.
The Sudbury area also features a second impact site from a meteor, McDonald noted.
"There are two impact sites side-by-side here in Sudbury," he said. "Lake Wanapitei is an impact structure. That was definitely formed by a meteorite impact, about 38 million years ago, whereas the Sudbury event was about 1.85 billion years ago.
"So they were considerably different in time, but the proximity of one to the other is quite remarkable."
NASA Sat, 21 Jul 2007 03:10 EDT
Scientists have recently discovered that the planet Saturn is turning 60 - not years, but moons.
"We detected the 60th moon orbiting Saturn using the Cassini spacecraft's powerful wide-angle camera," said Carl Murray, a Cassini imaging team scientist from Queen Mary, University of London. "I was looking at images of the region near the Saturnian moons Methone and Pallene and something caught my eye."
The newly discovered moon first appeared as a very faint dot in a series of images Cassini took of the Saturnian ring system on May 30 of this year. After the initial detection, Murray and fellow Cassini imaging scientists played interplanetary detective, searching for clues of the new moon in the voluminous library of Cassini images to date.
The Cassini imaging team's legwork paid off. They were able to locate numerous additional detections, spanning from June 2004 to June 2007. "With these new data sets we were able to establish a good orbit for the new moon," said Murray. "Knowing where the moons are at all times is important to the Cassini mission for several reasons."
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| ©NASA/JPL/Space Science Institute |
| Sixtieth moon to be discovered at Saturn, indicated in red. |
One of the most important reasons for Cassini to chronicle these previously unknown space rocks is so the spacecraft itself does not run into them. Another reason is each discovery helps provide a better understanding about how Saturn's ring system and all its billions upon billions of parts work and interact together. Finally, a discovery of a moon is important because with this new knowledge, the Cassini mission planners and science team can plan to perform science experiments during future observations if and when the opportunity presents itself.
What of this new, 60th discovered moon of Saturn? Cassini scientists believe "Frank" (the working name for the moon until another, perhaps, more appropriate one is found) is about 1.2 miles (2 kilometers) wide and, like so many of its neighbors, is made mostly of ice and rock. The moon's location in the Saturnian sky is between the orbits of Methone and Pallene. It is the fifth moon discovered by the Cassini imaging team.
"When the Cassini mission launched back in 1997, we knew of only 18 moons orbiting Saturn," said Murray. "Now, between Earth-based telescopes and Cassini we have more than tripled that number - and each and every new discovery adds another piece to the puzzle and becomes another new world to explore."
Murray and his colleagues may get the chance to explore Saturn's 60th moon. The Cassini spacecraft's trajectory will put it within 7,300 miles (11,700 kilometers) in December of 2009.
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, Calif., manages the Cassini-Huygens mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging team is based at the Space Science Institute, Boulder, Colo.
Comment: Congratulations, Saturn. You've just got your new comet...eh, moon.
From: Forget About Global Warming: We're One Step From Extinction!
Now let's time travel back to the future, and see what the latest information tells us about Jupiter's moons:
Jupiter is now given 63 satellites. Forty-seven of those satellites have been discovered since 1999. What if they weren't there before?
What about Saturn. Our 1975 text tells us that Saturn has 10 satellites. In 2007? Well, there are so many that one source declines to give a precise number!
However, counting the named satellites on the Timeline of discovery of solar system planets and their natural satellites gives us a count of 62, with 41 being discovered since 2000 and another ten in the 80's and 90's.
Moving outward, we come to Uranus, given five satellites in 1975, it now has 28, with ten being discovered in the 1980's, six in the 90's, and 7 since 2000.
Neptune had two satellites in 1975, now it has 13.
| Planet | 1975 | 2005 |
|---|---|---|
Jupiter | 9 | 63 |
Saturn | 10 | 62 |
Uranus | 5 | 28 |
Neptune | 2 |
13 |
The explanation given most often to explain this surge in the numbers of satellites for these planets is that telescopes have gotten better. That is, we can see further, with greater detail, and can therefore find things that we couldn't see before. It is an explanation that makes sense. One small problem with this theory is that the "new" moons of Neptune and Uranus showed up before the new moons of Jupiter and Saturn. One would think that powerful telescopes capable of finding moons as far away as the seventh and eighth planets would have found the hard to see moons of the fifth and sixth first.
Another possible explanation, and one which fits with new moons appearing around Neptune and Uranus prior to appearing around Jupiter and Saturn, is that these new moons, or some of them, are objects that have been trapped into orbits around these planets only recently, that they were captured by the gravity of these planets and removed from the incoming comet cloud. Passing the orbits of the outer planets first, they would arrive at the inner planets afterward.
We also note that the much derided Immanuel Velikovsky, in his book Worlds in Collision, gives a time frame of nine years as the time it would take for a comet to cover the distance between Jupiter and Earth. The new Jovian moons were discovered beginning in the late nineties.
Do the math.
Saskatchewan News Network Sat, 21 Jul 2007 05:35 EDT
Geology detectives in Saskatchewan might have made two important discoveries this summer.
And, as it usually happens for members of the multi-university partnership Prairie Meteorite Search, the finds have come from unexpected places.
When farmer Ken Wiggins heard that field researcher Nathan Seon was coming to talk about meteorites with locals near Wiggins' home base of Manor, he figured there wasn't any harm in having Seon examine an odd-shaped depression that had been on the farm as long as anyone could remember.
"I wondered about it when I first took a look at it, whether it could possibly be an impact site," Wiggins said. "But there was really no big hype about meteorites at that time so, basically, it was there, it was a curiosity, but it was also a handy place to put some rocks."
Wiggins bought the land 35 years ago, and had used the strange hole -- about six metres across and 1.8 metres to 2.1 metres deep -- for dumping rocks he picked off the field. When Seon saw it, he knew it might be something special.
Both Seon and Martin Beech of the University of Regina, who helps co-ordinate the Prairie Meteorite Search, note the chances of the site actually being that of a meteor impact are low.
"It's one of those things," Beech said. "As to whether it is really a true small-impact crater, it's not that it can't be, but it's certainly a low probability until you really sort of look into it in much more detail than has presently been done."
But if the hole does turn out to be the final resting place of rock from space -- and there is a possibility -- the find would be significant.
"What would be intriguing would be to actually have such a structure and then if one can also find meteorites associated with it," Beech said. "That would be pretty much unique within Canada, I think it's fair to say."
The investigation is now at a standstill. Wiggins backhoed out the rocks dumped in the hole. Now, the researchers must find time to go through the rocks and see if any of them actually are meteorites. So far, Wiggins has found three rocks with some properties associated with meteorites, but Beech, who has seen photos, says it's safe to say those aren't meteorites.
But another stone turned into the Prairie Meteorite Search is actually very likely a meteorite. Four or five fist-shaped meteorites land in Saskatchewan every year. One hasn't been identified in three years, and only 14 have been identified in total over the last century, Beech said.
This potential meteorite -- brought in by someone who found it almost a decade ago west of Davidson -- is currently awaiting chemical analysis. A presence of nickel alloy needs to be identified before it can be confirmed.
The Prairie Meteorite Search, led by Beech along with professors at the University of Calgary and the University of Western Ontario, has been scoping the Prairies for meteorites for the last seven years, during which time more than 10 new meteorites have been found.
The hope is that by providing information to rural communities, those who regularly spend time in fields will be able to identify and report potential meteorites they come across.
Tony Long Wired Sat, 21 Jul 2007 05:46 EDT
1862: American astronomer Lewis Swift discovers the presence of a large comet that will soon bear his name. Three days later, another American astronomer, Horace Tuttle, makes the same sighting. So this heavenly body comes down to us as the Comet Swift-Tuttle.
Based on their observations, and those of other astronomers who began tracking the comet's highly elongated orbit, it was calculated that Swift-Tuttle would make its next appearance during the 1980s. They were close. Japanese astronomer Tsuruhiko Kiuchi rediscovered the comet in 1992.
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| ©H. Mikuz |
| Comet 109P/Swift- Tuttle |
Aside from its unusual orbit, Swift-Tuttle is also significant as the host body of the Perseids meteor shower, one of the most prominent in the northern sky.
Oh, and there's one more thing.
Comets come and go, literally, but Swift-Tuttle's orbit is of particular interest to us earthlings since astronomers calculate that it is very likely to strike either the Earth or the moon on its next pass. They've even zeroed in on a date: Aug. 14, 2126.
We'll just have to wait and see.
Manit Sanubboon Bangkok Post Sat, 21 Jul 2007 09:02 EDT
Thailand will have a close encounter with an asteroid expected to move closer to the Earth than the moon in the next 29 years, according to a prominent astronomer Worawit Tanwutthibundit. The asteroid, named 99942 Apophis, will come into close orbit with the Earth 22 years from now and it will come by again, even closer, seven years after that.
This has sparked fears over the possibility that it could collide with the Earth.
Mr Worawit, an executive member of the Thai Astronomical Society, said the asteroid will come within about 34,400 kilometres of the Earth on April 13, 2029.
He cited a report released by the US National Aeronautics and Space Administration (Nasa).
On that day, the asteroid will make its closest approach to the Earth, about eleven times closer than the moon will pass by _ for the first time in 1,000 years, according to Mr Worawit.
The astronomer said the asteroid's visit on that day will provide a basis for calculations about whether it could hit the Earth in the future.
The same asteroid is predicted to pass by the Earth again on April 13, 2036 and it will be even closer then, Mr Worawit said, citing the Nasa report.
He said the calculations will determine whether the asteroid would be on a collision course with the Earth in 2036 or not. ''If it struck the Earth on that day (April 13, 2036), the possible target would be the northern part of Mexico.
''The impact of the collision would be like the power of 870 megatonnes of TNT going off,'' Mr Worawit said.
Mr Worawit said 99942 Apophis is 320 metres in diameter, and orbits the sun every 323 days.
On April 13, 2029, the asteroid will come into view at dusk at a 42-degree angle in the western sky in the constellation Cancer, Mr Worawit said.
It will be able to be observed in the Middle East, Europe, Africa and Thailand.
The 99942 Apophis asteroid was discovered in June 2004. It was then called 2004 MN4.
TV3 Sat, 21 Jul 2007 08:48 EDT
Early risers in Auckland were treated to a natural fireworks display this morning - spotting a meteorite flashing across the West Coast sky.
Experts explain the phenomenon as a piece of either a comet or an asteroid, which vaporises in a great cloud of light when it hits our atmosphere.
The Hawke's Bay Astronomy Society says it is a common occurrence with at least one hitting every day, but only about ten a year are reported to them. Vice President Graham Palmer says people often mistake the shower of light as plane explosions or UFOs, but he says there is no cause for concern.
Comment: With the amount of reported fireballs and meteorites falling on earth in recent years, and the amount of UFO sightings multiplying as time goes by, there is of course "no cause for concern".
Back to sleep folks!
SanLuisObispo.com Wed, 18 Jul 2007 22:23 EDT
Sheriff's Department officials reported receiving dozens of calls from residents around the county who reported feeling shaking and loud booms at three different times before about 1:30 p.m. Residents from California Valley to Arroyo Grande reported feeling the shaking and hearing the booms.
Military aircraft appear to be responsible for sonic booms and shaking that residents around the county are feeling this afternoon, officials said.
Edwards Air Force Base officials said they sent an F-22 airplane out to a testing area about 50 miles off the coast this morning that could have explained the rattling residents reported, base public affairs spokesman John Haire said. But the area is also used by other branches of the U.S. military that could have had aircraft in the area, Haire said.
In addition, NASA was conducting sonic boom testing this morning at the base that may have been heard by residents along the coast. The base is located in the Mojave Desert, near the Kern and Los Angeles county line.
Comment: From the comments section of the article:
I've lived in California all of my 48 years, and I've heard sonic booms many times before, including the big double boom of the shuttle coming in. This was much different. It was 3 or 4 seconds of what sounded like a jackhammer on my walls, followed by a window rattling boom.If the Air Force is playing with a new secret toy, fine, say "no comment", but this story isn't working for me at all.
Tiny asteroid 'groupie' found trailing after Mars
David Shiga NewScientist.com Mon, 23 Jul 2007 23:04 EDT
A new space rock has been found that devotedly travels around with Mars as it orbits the Sun, bringing the total number of such 'groupies' to four. But astronomers say it was Mars - not its tiny companions - that originally insinuated itself into the rock group billions of years ago.
The asteroid, called 2007 NS2, was discovered by astronomers at the La Sagra Observatory in southern Spain on 16 July. Based on its brightness, it is estimated to be about 1 kilometre across.
It follows Mars in its orbit, occupying a spot called L5, which lags the Red Planet by 60° as it moves around the Sun. It shares L5 with two other objects, while a fourth object orbits 60° ahead of Mars at a point called L4.
Objects that wander into the L4 and L5 points of a planet tend to be confined there by the combined gravity of the planet and the Sun.
Mars is one of just three planets known to have such "Trojan" objects in its orbit. About 2200 are known to accompany Jupiter in its orbit, and a handful have been discovered in Neptune's orbit as well.
Jupiter and Neptune may have collected their Trojans about 3.8 billion years ago, at a time when the orbits of these planets were shifting and their gravity was flinging vast numbers of comet-like objects around the solar system.
How Mars got its Trojans is uncertain, but the Red Planet may have collected them at a much earlier period, just after the dawn of the solar system a little more than 4.5 billion years ago, says Trojan researcher Alessandro Morbidelli of the Observatoire de la C?te d'Azur in Nice, France.
Temporary companions
At that time, an embryonic Mars may have been kicked around the solar system through gravitational interactions with other planetary embryos. Any asteroids that happened to be at the L4 and L5 points of its new orbit would have been trapped there by the Red Planet's gravity.
"They did not move, but the planet did," Morbidelli told New Scientist.
After the discovery of 2007 NS2, astronomers found the asteroid in old images from the Arizona-based LONEOS and LINEAR near-Earth object surveys dating back to 1998. This has allowed researchers to calculate a more precise orbit for the object.
Calculations by Aldo Vitagliano of the Universita di Napoli Federico II in Naples, Italy, show the asteroid is stable at Mars's L5 point. The newly found space rock has now been added to the list of Mars Trojans on the website of the Minor Planet Center in Cambridge, Massachusetts, US.
Earth has no known Trojans, perhaps because our home planet is too heavy to have been knocked around the same way that Mars was, Morbidelli says. "Mars jumped around because of its small mass, but not the Earth," he says. Mars is just 11% as massive as the Earth.
Although no asteroids are known to occupy Earth's L4 and L5 points, there are a handful of so-called Earth co-orbital asteroids. These objects have corkscrew orbits, slowly looping around Earth, while following its orbital motion around the Sun. This configuration is unstable, so these objects are only temporary companions to Earth.
One such object, a 200-metre-wide asteroid called 2005 GU9, has been looping around Earth this way for 500 years, but is expected to eventually drift away.
If some wayward objects from the asteroid belt did become trapped as Trojans around Earth, the objects would not be easy to spot, Vitagliano says.
Their position relative to Earth means they would not reflect much light towards us, making them relatively dim. And because of their position, they would appear fairly close to the Sun, which means they would only be visible above the horizon for a short period of time at night.
Economist.com Tue, 24 Jul 2007 05:36 EDT
ONE of the main weaknesses of the environmental movement has been its unfortunate predilection for using doom-laden language and catastrophic superlatives to describe problems that are serious but not immediately disastrous. But one calamity that truly deserves such a description is almost never talked about. There are tens of millions of asteroids in the solar system, and several thousand move in orbits that take them close to Earth. Sooner or later, one of them is going to hit it.
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| ©NASA |
Several have done so in the past. Earth's active surface and enthusiastic weather conspire to scrub the tell-tale impact craters from the planet's surface relatively quickly, but the pockmarked surface of the moon - where such scars endure for much longer - testifies to the amount of rubble floating in the solar system. Earth's thick atmosphere makes it better protected than the moon: asteroids smaller than about 35 metres (115 feet) across will burn up before hitting its surface. Nevertheless, plenty of craters exist. The Earth Impact Database in Canada lists more than 170.
Fortunately, such impacts are relatively rare, at least on human timescales. Statisticians calculate that the risk to lives and property posed by meteorite strikes are roughly comparable with those posed by earthquakes.
Although the chance of an impact may be small in any given year, the consequences could be enormous. The effect of an impact depends on an object's size and speed. A meteorite a few metres wide could level a city. The largest (a kilometre or more in diameter) could wreak ecological havoc across the entire globe. David Morrison, a NASA scientist, argued at a recent conference that a large meteorite strike is the only known disaster (except perhaps global nuclear war) that could put civilisation at risk.
Examples give a more visceral illustration than statistics. The Chicxulub crater, buried beneath modern Mexico, is 65m years old and 180km (112 miles) across. Some think that the ten-kilometre meteorite that created it threw so much dust into the atmosphere that it blotted out the sun and led to the extinction of the dinosaurs. In 1908 a comparatively tiny piece of space-borne rock, 30-50 metres across, exploded above Tunguska, a remote part of Siberia. The blast - hundreds of times more powerful than the atom bomb dropped on Hiroshima 37 years later - felled 80m trees over 2,150 square kilometres. Only blind luck ensured that it took place in a relatively unpopulated part of the world. Astronomers are currently trying to work out whether a 270-metre asteroid named 99942 Apophis will hit Earth in 2036 (probably not, but it would be nice to be sure).
Happily for humanity, technology has advanced to the point where it is possible, in principle, to avoid such a collision. In 1998 NASA agreed to try to find and catalogue, by 2008, 90% of those asteroids bigger than 1km in diameter that might pose a threat to Earth. Any deemed dangerous would have to be pushed into a safer orbit. One obvious way to do this is with nuclear weapons, a method that has the pleasing symmetry of using one potential catastrophe to avert another. But scientists counsel caution. A nuclear blast could simply split one large asteroid into several smaller ones, some of which could still be on a collision course.
Other plans have been suggested. One is to use a high-speed spaceship simply to ram the asteroid out of the way; another is to land a craft on the rock's surface and use its engines to manoeuvre the asteroid to safety. A subtler method is to park a spaceship nearby and use its tiny gravity to pull the asteroid gradually off course. For now, all such suggestions are theoretical, although the European Space Agency is planning a mission, named Don Quijote, to test the ramming tactic in 2011.
These schemes offer consolation, but any effort to deflect an asteroid requires plenty of advance warning, and that may not always be available. NASA has so far catalogued only the very largest, "civilisation-killing" asteroids. Plenty of smaller ones remain undiscovered, and they could inflict considerable damage. In 2002 a mid-sized asteroid (50-120 metres across) missed Earth by 121,000km - one-third of the distance to the moon. Astronomers discovered it three days after the event. Comets, which originate from the outer reaches of the solar system, are faster moving and harder to track than asteroids, but carry just as much potential for catastrophe.
But perhaps the biggest problem is humanity's indifference. Currently only America is spending any money on detection, and even there, politicians have other priorities. Much of the work is done by Cornell University's Arecibo radar in Puerto Rico, which is facing federal funding cuts. The telescope costs roughly $1m a year to operate. As an insurance policy for civilisation, the price looks cheap.
Comment: Well, SOTT has been saying it all along, and supported it with research and data: Forget About Global Warming: We're One Step From Extinction!
Joyce L. Miller Lake Sun Leader Tue, 24 Jul 2007 23:40 EDT
The United States Air Force has launched an investigation and hope to provide residents who heard a series of loud booms Monday with an answer to clear up any confusion.
Military officials at Whiteman Air Force Base at Knob Noster, Mo., assured the Camden County Sheriff's Department that their staff would do everything they could to determine what caused all the commotion Monday afternoon. Air Force personnel were not aware of any missions or training exercises in the area at that time that would have caused the booms that were accompanied by shaking in some areas. The staff at Whiteman informed the sheriff's department Wednesday that they will go through the necessary channels to determine if the mysterious sounds were caused by aircraft.
Residents from one end of the county to the other reported hearing loud, sonic-type boom sounds beginning around 2:15 p.m. The sounds and shaking that accompanied the booms shook windows, rattled dishes and may have caused some damage to walls where the sheet rock cracked.
The sheriff's department had contacted Whiteman, the St. Louis Earthquake Center and other agencies to find out what caused the noise.
AP Fri, 27 Jul 2007 10:25 EDT
DUBUQUE, Iowa - Large chunks of ice, one of them reportedly about 50 pounds, fell from the sky in this northeast Iowa city, smashing through a woman's roof and tearing through nearby trees.
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| ©Telegraph Herald/AP |
| Jan Kenkel holds a piece of ice that fell through the roof of her Dubuque, Iowa, home on Thursday. |
Authorities were unsure of the ice's origin but have theorized the chunks either fell from an airplane or naturally accumulated high in the atmosphere - both rare occurrences.
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| ©Herald Tribune/AP |
| The mysterious falling ice left a hole in the roof of Kenkel's home. |
"It sounded like a bomb!" 78-year-old Jan Kenkel said. She said she was standing in her kitchen when an ice chunk crashed through her roof at about 5:30 a.m. Thursday. "I jumped about a foot!"
She traced the damage to her television room, where she found a messy pile of insulation, bits of ceiling, splintered wood and about 50 pounds of solid ice.
Karle and Mary Beth Wigginton, who live a block away, heard a loud "whoosh" coming through the trees. They discovered several large chunks of ice in front of their home and some smaller ones in the yard and in the street.
"I could see where branches were shredded, which told me it was definitely coming out of the sky," Karle Wigginton said.
He estimated the original chunk of ice was the size of a basketball. "It was pure white," he said. "The main parts I picked up were very smooth."
Elizabeth Cory, a spokeswoman for the Federal Aviation Administration, said investigators would contact Kenkel to try to determine the source of the ice.
"It is very uncommon for something like this to come from an aircraft," Cory said. "That is really unusual if it is pure white ice, especially at this time of year."
Occasionally, aircraft latrines discharge contents at altitude, resulting in chunks of descending ice. Airplanes also sometimes accumulate ice on their edges in certain atmospheric conditions, including high altitude and extreme moisture, said Robert Grierson, the Dubuque Regional Airport manager and a pilot.
The moisture involved in such a scenario could have come from the tops of strong thunderstorms. However, Dubuque had clear skies at the time the ice fell, said Andy Ervin, a meteorologist with the National Weather Service in Davenport. "There was nothing unusual going on," he said.
David Travis, a professor of geography and geology and an associate dean at the University of Wisconsin-Whitewater, has studied the phenomenon of large chunks of ice falling from a clear sky. He said it's possible the ice could have been a megacryometeor - "similar to a hailstone, but without the thunderstorm."
Travis is part of a research team that has documented more than 50 possible megacryometeor cases during the past five years. Some involve ice chunks the size of microwave ovens.
"It is hard to keep something like that suspended in air without a thunderstorm," Travis said.
Most megacryometeor sightings have occurred in coastal areas, where atmospheric turbulence helps keep ice suspended long enough to grow into large chunks.
Travis' research team speculates the phenomenon could be linked to global warming, suggesting that climate change might make the tropopause portion of the atmosphere colder, moister and more turbulent.
"But those don't typically happen in the summer time," Travis said. "It seems like they are mostly associated with the passage of passing cold fronts."
Joyce L. Miller lakesunleader.com Tue, 24 Jul 2007 10:47 EDT
CAMDEN COUNTY ' The United States Air Force has launched an investigation and hope to provide residents who heard a series of loud booms Monday with an answer to clear up any confusion.
Military officials at Whiteman Air Force Base at Knob Noster, Mo., assured the Camden County Sheriff's Department that their staff would do everything they could to determine what caused all the commotion Monday afternoon. Air Force personnel were not aware of any missions or training exercises in the area at that time that would have caused the booms that were accompanied by shaking in some areas. The staff at Whiteman informed the sheriff's department Wednesday that they will go through the necessary channels to determine if the mysterious sounds were caused by aircraft.
Residents from one end of the county to the other reported hearing loud, sonic-type boom sounds beginning around 2:15 p.m. The sounds and shaking that accompanied the booms shook windows, rattled dishes and may have caused some damage to walls where the sheet rock cracked.
The sheriff's department had contacted Whiteman, the St. Louis Earthquake Center and other agencies to find out what caused the noise.
Max Hirsch Taipei Times Sat, 28 Jul 2007 10:40 EDT
It was so faint amid the star-freckled blackness that professional star-gazer Lin Chi-sheng missed it as he photographed the heavens from Lulin Observatory, Nantou County, earlier this month.
Luckily, Lin's camera, recording time-lapse images of space through the observatory's telescope, didn't miss it -- a mighty chunk of ice and rock "a few kilometers" in diameter and hurtling toward Earth: "Asteroid C/2007-N3."
Since named "Lulin Comet," the galactic "dirty snowball" -- as an observatory press release calls it -- won't mean much to the average terrestrial, except perhaps on Feb. 27, 2009, when the comet will likely become visible to the naked eye as it cruises within 60 million kilometers of Earth -- a "close shave" in astronomical terms.
For Taiwan, however, Lulin Comet and a smaller "near-earth asteroid" (NEA) captured in the same photograph are the first discoveries of their kind by local astronomers -- a rare find that puts the nation on the map in the global astronomical community.
"It seemed like just another night," Lin told a press conference yesterday, referring to his July 11 late shift at the remote, mountaintop observatory.
But Lin's camera was trained on a lucky slice of sky that evening, snapping shots of a starry patch between Jupiter and Saturn. Beating fantastic odds, a comet and a 1km-wide NEA made it into the frame, said Lee Lou-chuang, president of National Central University, which runs the Observatory.
"This is Taiwan's first discovery of a comet and its first discovery of an NEA," Lee said.
The comet was also the first such object to be named after a place or person in Taiwan, the press release said, adding that, statistically, only one in 100 discovered asteroids qualifies as an NEA, and only one celestial body among 1,000 discovered qualifies as a comet.
Asked what the trick is behind snapping such revealing pictures of space, Lulin Observatory director Lin Hung-chin said: "It's just luck really."
But, in an interesting political twist to the celestial find, astronomers yesterday admitted that China's cooperation was key in identifying the objects.
While cross-strait relations on many fronts continue to fizzle, cross-strait astronomical cooperation has flourished, they said. The two finds announced yesterday, for example, were facilitated by the "Lulin Sky Survey," a Lulin Observatory-based program that pools the efforts of Taiwanese and Chinese star-gazers to catalogue the sky, Lin Chi-sheng said.
Lacking a high-powered telescope of their own, Chinese astronomers contribute to the program by selecting areas of the sky for the Lulin Observatory to watch and photograph, and by analyzing the photos, he said. Chinese participants, he said, were the ones who had first detected the comet and NEA in the photographs.
US astronomer James Young at the Table Mountain Observatory in California later confirmed the finds, the press release said.
As the only country in Asia scheduled to participate in "Pan-STARRS," a US-based program focused on finding asteroids on a collision course with Earth, Taiwan is also working closely with astronomers in the West, Lee said.
Scheduled to begin next month, the Hawaii-based program will call on US Air Force and University of Hawaii resources, as well as observatories in the UK and Germany, according to the Pan-STARRS' Web site.
Taiwan, observatory officials said, will contribute by searching the heavens with its high-powered telescope for dangerous asteroids.
"If we could find an asteroid with the potential to hit the Earth, that would be very interesting," Lee said, his scientific curiosity apparently trumping any fear of annihilation. "That'd be worse than global warming."
Science Alert Sun, 29 Jul 2007 08:23 EDT
Most nights, as the southern hemisphere sleeps, Rob McNaught is awake and on guard. He's part of an international team of astronomers scanning the skies for Near Earth Objects (NEOs), such as asteroids and comets, that could pose a threat to our planet. Scientists believe that large objects colliding with the Earth in the past may have had cataclysmic effects, wreaking destruction at the point of impact, altering global climate patterns and causing mass extinctions. Working with colleagues at the University of Arizona, McNaught has discovered or co-discovered more than 30 comets and thousands of asteroids from his base at Siding Spring in outback New South Wales. So far none of the NEOs appear to be an immediate threat. But very rarely, one of these space travellers does pass close to our planet with spectacular results.
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| ©Rob McNaught |
| The peacock-like tail of the comet became clearly visible once it entered darker skies. This shot was captured by Rob McNaught on 25 January at Siding Spring. |
If anything, McNaught's expectations were lower than usual when he began routine scans at the Uppsala Schmidt telescope on the night of 7 August 2006. This is just one of the optical telescopes housed by the ANU Research School of Astronomy and Astrophysics at the site. The moon was full, and he was due to observe a section of sky close to the edge of the Milky Way where the stars are denser - two factors that add up to poor NEO spotting. But one of the scans showed up a faint point of light emerging out of the brightness of the Milky Way. Further analysis showed this to be a comet headed towards the Sun, which McNaught reported to the Central Bureau of Astronomical Telegrams, the international clearing house for comet discoveries. Tracking the comet over the next few days, he saw that this object was going to pass reasonably close by the Sun, well within the orbit of Earth and even perhaps within that of Mercury. This could translate into quite a show for space spotters, but it could also mean that the comet would become lost in the glare of the Sun.
On hearing of the discovery, the response from the astronomical community was muted. This caution was a lesson learned from the disappointment of Comet Kohoutek in 1973, which was initially hailed as the 'comet of the century' before it fizzled out. McNaught says it's common for a comet's rate of brightening to diminish as it nears the Sun, so astronomers have learned not to get their hopes up.
"At the time, I wasn't sure what it would be like," McNaught says. "My peers thought there was no reason to believe it would be unusual. But after observing it over time, I noticed fairly early on that it had a rapid rate of brightening, which was quite unusual."
As it journeyed closer to the Sun, the comet continued to grow in luminescence. McNaught became more confident that this was something out of the ordinary. By mid-January, his predictions were confirmed. This ball of ice and dust brightened so dramatically as it approached that it became visible to the naked eye in daylight. Astronomers and amateur stargazers thrilled at the sight of what was soon dubbed 'the Great Comet of 2007'. This object that shone in the sky brighter than the Venus was designated C/2006 P1, but most people came to know it as 'Comet McNaught', after the convention that a comet is named for its finder. And for him, it was the fulfilment of a long-held dream.
"I wanted to see and discover comets ever since I was a kid," McNaught says. "So to see this one turn out so big and bright was hugely exciting. Just witnessing it with my own two eyes was much more important than being credited with the discovery."
To ensure he would have a good chance of viewing the comet when it was at its brightest, McNaught booked a flight to Hong Kong. He knew from previous experience that comets near the Sun are more easily seen from altitude, where there is less pollution, fewer clouds and the horizon is much lower. A trip to the Northern Hemisphere would also allow him to view the comet a day before it became visible in Australia.
On 12 January 2007, from the window of a passenger jet, McNaught witnessed his very own comet punch a pin hole in the late-afternoon sky.
"I was really excited," he says. "It was the first time I'd seen a comet with the naked eye in daylight. It was a special moment."
His excitement remained high after he returned to Siding Spring, as Comet McNaught remained visible in the southern hemisphere for several weeks. Emails and media requests flooded in from around the world as more people spotted the light in the sky. After reaching perihelion (the point in its orbit that's closest to the Sun) on 12 January, the comet appeared higher relative to the horizon, placing it in darker skies. Here, as if delivering a parting gift as it began its long journey back to the outer edges of the solar system, C/2006 P1 revealed an incandescent tail. This peacock-like effect is caused by ejected dust being pushed outward from the Sun by the pressure of sunlight, but also lagging behind the comet as it undertakes its tight turn on passing the Sun.
Comet McNaught's showy pass by Earth allowed scientists to study it in detail. Although the comet's composition is still largely unknown, it's believed that this was its first passage through the inner solar system where our planet resides. It's thought that the comet originated in the Oort Cloud, a dense ring of icy objects orbiting the Sun at the distance of about one light year, or slightly less than ten million kilometres. Even though it made the trip at a fair clip, it won't be back by Earth for many thousands of years. But there are more comets and asteroids where it came from, and probability says that one of them could intersect Earth's orbit. When it comes to the prospect of an NEO impact, McNaught says we need to be alert but not alarmed.
"There are many dangers that we treat as simple consequences of living, but are too busy getting on with our lives to worry about," McNaught says. "I don't think it would be healthy to worry about the prospect of a comet impact. But it does make sense for us to be aware of the threat, quantify it and prepare to deal with any potential threat."
Comment: For more information, read the SOTT focus article: Forget About Global Warming: We're One Step From Extinction! to understand what is really coming our way. Preparations could be underway to prepare for the future, yet, the Pathocrats ruling the planet continue to funnel resources into widespread genocide. Rest assured that their own contingency plans are in place, however.
SPX Tue, 31 Jul 2007 15:47 EDT
Since 1986, four different comets -- Halley, Borrelly, Wild 2 and Tempel 1 -- have been examined in impressive detail by a wide variety of American, European and Russian spacecraft, including one that has actually returned a small dust sample to Earth and another that crashed a large piggyback spacecraft into a comet's nucleus to try and reveal some of its subsurface structure. And in 2014, the still more ambitious European "Rosetta" mission will rendezvous with the nucleus of a fifth comet (Churyumov-Gerasimenko), examine it from just 25 kilometers away (or less) for over a year and a half, and even drop a small survivable lander onto the nucleus' surface.
All this attention is entirely justified, given the fact that comets are the only preserved pieces of the "planetesimals" that were made by accretion out of the initial dust, ices and gas of the primordial pre-Solar System nebula itself, and which in turn merged together to form the planets.
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| ©NASA |
So they can give us invaluable data on the composition and structure of that initial nebula, and thus on the earliest evolution of the Solar System. But even after Rosetta there will still be one very important piece missing from our first-stage exploration of the comets -- a piece that would have been provided by the only comet mission to fail thus far.
The reason is that we have known for a long time -- from Earth-based spectra of the gas comas surrounding comets (and our lesser observations of their accompanying dust) that comets vary to a really surprising degree in their composition. They are all composed largely of water ice, but it is mixed with a very wide variety of other frozen gases -- most of them being simple organic compounds -- that also thaw out and sublimate into vapor as the comet approaches the Sun and is warmed by it: carbon monoxide and dioxide, hydrogen and methyl cyanides, methanol (methyl alcohol), methane, acetylene and ethane, ammonia, formaldehyde, sulfur dioxide and others -- many of which have boiling points far lower than that of water and so naturally volatilize into gas much more easily as a previously distant chunk of cometary material approaches the Sun. Moreover, their quantities of these other ices vary greatly from comet to comet.
Our more limited analyses of the "carbonaceous" mineral dust that forms the other part of a comet's substance indicate that it can also vary suprisingly. Earth-bound telescopes and astronomy satellites have taken detailed spectra of the dust cloud thrown up from Tempel 1 by the Deep Impact crash -- and also of the natural dust vented into space by the huge 1997 comet Hale-Bopp -- that strongly suggested the presence of phyllosilicates (clay minerals) and carbonates, such as would be formed if the carbonaceous silicate minerals originally in the grit had been exposed to traces of liquid water.
These have also apparently been seen in our spectra of the protoplanetary disks circling other young stars. But the actual sample of dust returned from Wild 2's nucleus by "Stardust" shows no trace of these water-related minerals. There also seem to be significant differences in the amounts of more complex, less easily vaporizable organic compounds that have been measured in various comets.
What accounts for these major differences? Originally, astronomers expected to see a recognizable pattern. Comets can be divided into two general types: "Oort Cloud" and "Kuiper Belt" comets. Oort comets now orbit -- by the hundreds of billions -- in the vast reaches of interestellar space trillions of kilometers from the Sun (thousands of times farther away than Pluto), but they actually originated among the hundreds of trillions of ice and dust planetesimals in the early outer Solar System.
Most of these crashed together to create the four giant planets, but a smaller fraction made close flybys of the giant planets and were flung outward by their gravity, either escaping from the Sun completely or ending up in their hugely distant Oort orbits -- from which one is occasionally twisted, by the gravity of passing stars and even of the entire Galaxy, onto a path back toward the Sun, and occasionally even back into the central reaches of the planetary Solar System. When they do so, they approach the Sun from every conceivable angle and tilt; half of them even now swing around the Sun backwards as compared to the planets.
However, most visible comets with an orbital period of less than 20 years follow orbits tilted no more than 30 degrees to the ecliptic, and virtually none of them circle the Sun backwards. It's been suspected for a long time that they had a different source -- a more orderly belt of a few billion comets beyond the orbit of Neptune, just a few billion kilometers from the Sun -- and this was confirmed in the 1990s when the growing sensitivity of our telescopes finally allowed direct detection of the Kuiper Belt objects (of which Pluto and its moon Charon were the only previously known members).
Occasionally the gravitational tuggings of the giant planets will cause one of these to veer far enough back toward the Sun to fly by Neptune, which in turn can divert it further inwards to carom around among the four giant planets -- with a certain number of these "Centaur" comets finally flying past Jupiter and being diverted by its powerful gravity all the way into the warm inner Solar System.
Paradoxically, it was at first thought that such short-period Kuiper comets would actually contain colder frozen gases than the Oort comets, because they had actually been originally formed near or beyond Neptune, rather than closer in to the Sun in the midst of the four giant planets like the Oort comets. However, no such pattern has shown up -- short-period comets and long-period Oort comets seem about equally rich in very low-temperature frozen gases like carbon monoxide, methane and ethane.
And new computer simulations of the long-time orbital evolution of Solar System objects suggest that most (and maybe even all) Kuiper comets first formed, like the Oort comets, closer in toward the Sun in the midst of the four giant planets, but were flung less dramatically outwards from the Sun by the gravitational tuggings of those planets. (Some Kuiper Belt objects follow relatively neat, circular orbits around the Sun, and may still have formed out there to begin with, unlike the Kuiper objects with more elongated or tilted orbits -- but simulations show that those orderly Kuiper objects are also much less likely ever to wander back in towards the Sun so that we can detect the cometary gases boiled off them.) So, the current orbits of comets tell us almost nothing about how close to the Sun they first formed.
But even more puzzling, however, is the fact that our data up to now also shows little correlation between the amounts of the different low-temperature ices in comets -- comets that are rich in carbon monoxide ice are often poor in methane and ethane ice, or vice versa. So far, there seems to be little evidence that the distances from the early Sun (and its warmth) at which comets originally formed had any consistent effect on the relative amounts of the various different ices out of which they are made. So what in the world did cause them to vary in composition as dramatically as they do?
Moreover, most comets (and most Kuiper and Oort objects in general) are thought to each consist of multiple separate planetesimals that at some point banged into each other and stuck, like the weapons in a giant snowball fight. In that case, one would expect the ices making up any individual comet to vary greatly in mixture from one place on the comet to another, just as entire separate comets thus vary greatly. But the evidence on this point, too, is contradictory.
When Deep Impact flew by Tempel 1, it found that one of the two major natural jets on its surface was emitting mostly water vapor, while the other was emitting large amounts of carbon dioxide -- which would indeed fit with the "conglomerate makeup" theory of comets. But two comets -- the Oort comet "C/1999 S4 (LINEAR)", and the short-period comet Schwassmann-Wachmann 3 -- have been examined in detail by Earth-based spectrometers both before and after suddenly breaking up into multiple pieces (as comets frequently do), and the ratios of the different gases vaporizing out of their suddenly exposed interior parts seem identical with the ratios of different gases that had been vaporizing off their original outside surfaces, indicating that their mixture of different ices was actually very uniform from place to place.
Finally, there's still another puzzle -- what looks like a contradictory indication that Oort comets and short-period comets might have different compositions after all. Most of the Oort comets that we've seen have incredibly elongated orbits with periods of up to several million years, indicating that they are still following the initial orbital path by which they first fell out of the distant Oort Cloud back into the main Solar System.
A smaller number of them, however, have obviously at some time in the past made a close flyby of one of the giant planets that shortened their orbit, such as Hale-Bopp (whose orbital period is now only about 2500 years) and Halley (whose period has been trimmed down to a mere 76 years). But our orbital simulations indicate that there should be a much bigger number of these orbit-trimmed Oort comets than we're actually seeing -- which suggests that Oort nuclei are made out of some very fragile substance and usually burst apart after at most a few dozen flights through the warm inner Solar System.
Short-period comets, however, have much more staying power -- our mathematical backtracking of their orbits indicates that they usually survive for hundreds or even thousands of passes through the warm inner Solar System before bursting apart or drying out completely. They seem to be made of tougher stuff. But how can this be, if (as all other indications show) they were originally formed in just the same zone of the early Solar System as the Oort comets?
One possible explanation may be that Kuiper comets, during their initial "Centaur" days, tend to originally wander very gradually inwards from the Kuiper Belt through the realm of the four giant planets and into the inner System over a period of thousands of years -- whereas Oort comets plunge directly from the supercold regions of the outer Solar System (or near-interstellar space) into the warm inner System.
It may be that this much slower gradual initial warming of Kuiper comets does something to "toughen" them by allowing them to vent a large part of their new inner gases more gradually, so that they avoid an internal pressure buildup of the type that Oort comets undergo. But, once again, we don't know. It may be instead that there's just something currently wrong with our computer calculations of the number of orbit-trimmed Oort comets that should exist.
As an additional puzzle, the clear closeup photos that we've now gotten of three comet nuclei -- Borrelly, Wild 2 and Tempel 1 (the "Giotto" probe's much fuzzier photos of Halley's nucleus aren't nearly as useful) show some similarly baffling physical differences between them.
Wild 2's surface, as seen by Stardust, was utterly bizarre. The nucleus was pockmarked with strange-looking craters that -- unlike the bowl-shaped meteor impact craters on other worlds -- had flat floors but very steep wall slopes as deep as 200 meters, making the craters look as though they had been punched out by a cookie cutter.
There is still debate over whether these might be impact craters, but their shape suggests instead that they may be "sublimation pits" -- in which a small initial depression (a small normal impact crater or a gas-vent hole) becomes gradually wider as the ice mixed into its walls vaporizes away under the solar warmth on perhelion passes, with the dark rock grit than was mixed in with it then sliding to the bottom of the slope (or being blown some distance beyond the foot of the slope, under the comet's extremely faint surface gravity, by the pressure of the vapor from the sublimating ice).
On flat surfaces, on the other hand, after the surface ice vaporizes away, the remaining "lag deposit" of rock dust would simply continue to sit on the surface, forming a blanket that soon becomes thick enough to choke off further vaporization of the ice underneath it. And so the initial crater or vent hole would continue to grow steadily wider as more and more of its walls crumbled away, but without the hole getting much deeper -- and the initial difference between the steeper slopes of its upper walls and the lesser slopes of its lower walls and floor would also become greater and greater, turning any initial bowl-shaped depression into that flat-bottomed, steep-walled cookie-cutter-type hole.
Such sublimation of ice off slopes, as the process proceeded steadily onwards, would also produce other effects -- such as initial sublimation pits growing wider and wider until they actually ate away most of the comet's initial layer of surface, leaving behind only isolated mesas with steep walls but flat tops, and even leaving behind isolated steep pinnacles. All of these have been seen on Wild 2 -- there is even one place along the edge of the biggest and steepest crater seen on Wild 2 where this methodical eating away of ice by solar warmth seems to have produced an overhanging lip!
While the photos of the surface of Comet Borelly's nucleus taken by Deep Space 1 in 2001 are a good deal fuzzier because the probe was farther from the comet, they also show clear signs of this same sort of thermal erosion. There are indeed steep-walled isolated mesas up to 100 meters tall on the surface of Borrelly, and other areas where the ground seems to have been eaten away in roughly circular depressions -- although we don't see anything as dramatic as the steep-walled craters of Wild 2. Both comets look as though their surfaces are peeling away in patches like the skin of a bad sunburn victim.
But the surface of Tempel 1, when Deep Impact viewed it, was radically different. Whereas Wild 2 has large numbers of slopes of up to 70 degrees (to say nothing of that overhang), virtually all the slopes on Tempel are relatively gentle -- there seem to be none over 26 degrees. There is one big area with a smooth flat top which has a steeper-sloped edge, which could be due to the same kind of methodical nibbling away at slopes that we see on Wild and Borrelly -- but its edge seems to be only about 30 meters high.
We see some other evidence for the kind of layer-by-layer sunburn-like peeling that we see on Wild and Borrelly, but it is always much shallower and its edge slopes are far gentler. And the craters on Tempel are also far less strange-looking than those on Wild -- some of them are gentle depressions with rounded walls, while others have sharp steep edges but have inner walls that are very low, with the craters' flat floors being at almost the same level as the plain beyond the crater. (Deep Impact's Impactor crashed near two such craters.)
Some scientists think that we are actually looking at what were originally standard meteor impact craters on Wild and Tempel, which were then extensively modified in form by the thermal slope-ice erosion that I've mentioned. But it is rather hard to see how impact craters could endure very long on the nuclei of these comets, since their surfaces are eroded so fast by ice sublimation; it makes more sense to assume that we are looking on both nuclei at sublimation pits that grew from what were originally far smaller impact craters or gas vents.
Wild 2 was a Centaur-type object that never came close to the Sun than Jupiter's orbit until only 33 years ago, at which time it made a close flyby of Jupiter that flipped its orbit into an entirely new one taking it into the inner Solar System. Since then it's made only five orbits into the warm inner System -- so it's been proposed that only a few meters of its icy surface will have vaporized away, allowing the big impact craters that had formed on Wild's surface during its ages in the cold outer Solar System to still exist on its surface at this point.
But most such Jupiter-crossing comets have been shown by computer calculations to switch back and forth repeatedly between periods where they do stay in the cold outer System, and other periods where a Jupiter flyby flips them into the inner System for a while before a later Jupiter flyby flips their orbit back into the cold outer System again -- so it's likely that Wild's surface has actually been eroded away by the Sun's warmth for a total period much, much longer than just 33 years. This returns us once again to the idea that its big craters must be sublimation pits, rather than big meteor impact craters that were somehow preserved on its surface despite the major erosive effects of the Sun's heat.
In any case, we're left with the question: why are the slopes on Tempel 1 so much gentler and less tall than those on Wild 2 and Borrelly? Is it just that its top surface material is far more crumbly than that on those other two comets? I've mentiond earlier that the conclusion was initially drawn from the shape, size and timing of the ejecta cloud thrown up by Deep Impact's Impactor that the comet's surface must be incredibly soft, fluffy and non-conhesive, something like dry talcum powder -- but I've also noted that Kevin Housen and Ken Holsapple think that this underestimates the effects of newly vaporized gases erupting from underneath after the impact, so that the surface material may actually be somewhat sticker and firmer than that.
However, this could still leave it far more crumbly than the surface material on Borrelly and Wild, and thus incapable of sustaining their kind of steep, tall slopes and cliff walls -- even given the extremely faint surface gravity on all three comet nuclei.
But in that case, why is Tempel's surface softer -- and why does it look as though Borrelly's slopes are also somewhat less steep than the surrealistically steep cliffs on the surface of Wild 2? Were the three comets made from the start of ice and dust mixtures of different compositions, and thus different firmnesses -- with the three comets varying in their ice-dust ratios, or Tempel's ices perhaps being made out of more volatile gases that boil away into vapor more easily than the surface ices of Wild and Borrelly? Or have their surfaces been affected by different complex sequences and amounts of solar heating over their histories, since their orbits have all likely changed repeatedly in the manner that I've described?
Finally, Arizona comet expert Michael J.S. Belton has suggested that some of the layering seen on all three comets may not be thermal peeling, but may actually be the result of the collisions between smaller blobs of ice/dust that created them in the first place in the outer System or in the Kuiper Belt. He posits the "Talps" theory (that's "Splat" spelled backwards), in which -- when one such snowball hits a bigger one -- it is flattened out into a sheet that spreads around part of the surface of the bigger snowball.
This could explain, in particular, what seems to be one layer of material that actually runs through the middle of Tempel's nucleus, so that we see a cross-section of the layer as a straight-edged 200-meter-wide band running across one part of the nucleus. Once again, though, in that case we would expect to see different patches of any individual comet nucleus being made out of a different mixture of various ices and dust -- and while Deep Impact did see some sign of such compositional patchiness on Tempel 1 (where one of the comet's surface jets expels just water vapor while the other expels a lot of carbon dioxide), we don't seem to see it in the separate fragments of other comets that have ruptured into pieces.
In short, our first space probes have shown that different comet nuclei vary as dramatically in their physical makeup and structure as they do in chemical composition. To get any good understanding of what causes these differences -- and what they may say about different comet's' actual original formation conditions in the early Solar System (as distinguished from the complex effects that comets' different orbital histories, and thus their varying degrees of warming by the Sun, may have had on their surface appearance) -- we are clearly going to have to look at a much larger sampling of different comet nuclei, just as the great variations between the Asteroids means that we must get a closeup look at a large sampling of them to understand them properly. Just looking at a few comet nuclei -- even when you look at one of them in such spectacularly close detail as Europe's "Rosetta" comet rendezvous-and-landing mission will do in 2014 -- won't be adequate.
And the one comet probe intended so far to look at a whole multiplicity of different comets failed disastrously in 2002. In the last part of this series, I'll examine how comet scientists hope to recover from that failure -- and how the new extended missions of the Stardust and Deep Impact probes can help us do that.
The most powerful of those was Deep Impact's "High-Resolution Imager" (HRI), which at the time had by far the most powerful optic system ever carried on a Solar System probe: a reflective telescope with a 30-cm wide mirror, which was intended to take pictures of the comet nucleus' surface with a resolution of only 2 meters per pixel from a range of 700 km. Unfortunately -- in an eerie replay of the Hubble Telescope's initial mirror problem -- it was discovered after launch that the mirror was slightly out of focus.
The mathematical image-processing known as "deconvolution" largely compensated for this for photos of the relatively bright comet nucleus surface itself, but deconvolution is less effective in deblurring images of dim light sources because it amplifies random noise in the photo (which is why it could do little to correct Hubble's problem before astronauts installed a focus-correcting mirror on the telescope).
However, Drake Deming of the Goddard Space Flight Center came up with an ingenious proposal for a Deep Impact extended mission that not only managed to use Deep Impact's HRI for genuine astronomy studies, but actually makes some lemonade out of the lemon of its focusing problem.
Leonard David MSNBC Mon, 30 Jul 2007 06:01 EDT
Advocates believe in scientific payoff; critics say mission is too dangerous
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| ©Digitalspace / DigitalSpace |
| NASA is considering sending astronauts on an asteroid mission, as illustrated here. |
GOLDEN, Colo. - NASA's Constellation Program - including the deployment of the Orion crew vehicle replacing the space shuttle - will first be assigned to international space station flights, then propel humans and cargo to the Moon. Expeditionary missions to Mars and beyond will follow.
But there's ongoing discussion of mounting a piloted mission to an asteroid - a voyage by astronauts to a near-Earth object. These proponents feel certain of the scientific payoff from reaching, first-hand, an asteroid - perhaps even becoming able to exploit these chunks of celestial flotsam to further humankind's plunge into the cosmos.
Space technologists argue that a NEO trip could be a valuable shakeout of people, equipment, and procedures prior to hurling astronauts beyond the Moon to the distant dunes of Mars.
For others, NEOs are viewed as downright dangerous, in terms of a head-on collision between Earth and a space rock. It's best to get to know these incoming beasts ahead of time. NASA's NEOphytes
Internal looks by a small group of NASA "NEOphytes" have projected that a human trek to one of those mini-worlds may involve two or three astronauts on a 90 to 120-day spaceflight, including a week or two week stay at the appointed asteroid.
Dispatching astronauts to a NEO is a sensible idea, said Harrison Schmitt, Apollo 17 astronaut, geologist and current chair of the NASA Advisory Council.
In fact, the Exploration and Space Operations subcommittees of the NAC were briefed July 18 by NEO study team members from the NASA Johnson Space Center, although there has been no Council action on the topic.
Schmitt told Space.com: "I think examination of a NEO mission and the development of the stand-by monitoring systems, plans, protocols and procedures for the diversion of a potentially Earth-impacting asteroid would be very prudent activity for the U.S. to undertake."
Additionally, Schmitt said that a NEO mission would be a potentially important demonstration of the versatility and capability of the Constellation systems and a "gap-filler" before any Mars landing mission.
"So far, the arguments for asteroid science and resources are interesting, but not well-developed or potentially as historically or politically persuasive as a demonstration of long-term Earth defense," Schmitt said. Extended flight
At this point in time, NASA has not issued any formal requirements to augment the Orion spacecraft to handle a piloted NEO mission, explained John Stevens, Director of Business Development for the human spaceflight line of work at Lockheed Martin Space Systems, near Denver, Colorado.
However, the company - builder of the crew-carrying Orion spacecraft - internally funded two years worth of studies to flesh out technologies to support a diversity of destinations, Stevens said. For sojourns to a near-Earth asteroid, he said, future block upgrades to Orion are necessary.
"It's not that difficult from an architecture point of view to fly by an asteroid and then come back," Stevens said. But pulling off a rendezvous and docking with such an object, then rocketing back to Earth, requires more propulsion oomph, he noted, along with the need for larger living quarters for transiting crews, as well as recycling hardware to handle oxygen and water needs.
Also, any roundtrip - Earth-to-NEO-to Earth - is an extended flight, way beyond that required for Moon travel. So that brings up crew psychological-sociological issues. "It's a concern...but we don't know how much of a concern," Stevens advised.
Stevens said that the near-Earth object human mission can be viewed as an intermediate step between a Moon mission and a Mars mission. "In terms of complexity and the length of time that you have to stay out...it does represent a good stepping stone between the kinds of missions you do at the Moon and the kinds of missions that you next bite off...which is the Mars mission," he said. Visualize this space
DigitalSpace, a privately held company based in Santa Cruz, California, has just released a design simulation of a notional crewed mission to an as-yet identified asteroid.
"This visualization is DigitalSpace's design concept for the mission, produced as an independent effort for the benefit of an internal NASA feasibility study completed in 2007," said Bruce Damer, founder of the company that provides leading edge Internet content and tools for communication, collaboration, and visualization.
The NASA study was performed to show that such a mission is possible with the new Constellation architecture, Damer said. DigitalSpace received input from numerous experts inside and outside NASA to produce the NEO mission visualization.
"It is important to note that this is not a NASA concept, nor has NASA given it any kind of technical blessing...it is a design created by the DigitalSpace team to stimulate discussion in the space community," Damer emphasized.
Indeed, many in the space community see any pilgrimage to an asteroid - by either robots or astronauts - as having multiple benefits. Tooling up for NEOs
Learning about NEOs offers much in both scientific and practical terms. That's the perspective offered by Clark Chapman, a planetary scientist at the Southwest Research Institute's Department of Space Studies in neighboring Boulder, Colorado.
The reasons are many, Chapman said: Because there are many of them, because they are made of materials both common and exotic compared with materials available near the Earth's surface, and because they have negligible gravity...they are an obvious source of raw materials for future human exploration of outer space.
Tooling up for NEOs is already being tackled by specialists at Ball Aerospace & Technologies Corporation, also in Boulder. They have been looking into a small, low-cost landing probe design that could characterize both the surface and interior of small solar system objects, such as an asteroid.
The device is about the size of a basketball and weighs just a few pounds, said Dennis Ebbets, Senior Business Development Manager for Ball Aerospace's Space Science division. He and staff consultant, Richard Reinert, along with Rich Dissly, Ball's Deputy Director for Solar System Advanced Systems, suggest that several of the probes could be hauled to a target object and deployed individually.
Once released, these non-propulsive surface probes would freefall onto an asteroid's surface and begin transmitting results from their respective locales. The probes are outfitted with deployable panels to ensure self-righting to begin their errands.
Each self-energized probe might employ tiny imagers, accelerometers, x-ray spectrometers, sample collection and analysis gear - perhaps even utilize small explosive charges to create seismic waves that help gauge an asteroid's internal structure.
While asteroid surface probes could be deployed from an automated spacecraft, they are also a "perfect candidate" to be toted onboard a human expedition to a near-Earth object, Ebbets told Space.com.
Ebbets said asteroids deserve attention to help figure out what they are, where they come from, why they are different, and why there are families of these objects that are the same.
Additionally, "there's a non-zero chance of being hit by one of these things," Ebbets noted. He said he was a big fan of dropping a transponder onto an asteroid that's been branded as a potential troublemaker.
"Putting a transponder on it would be an excellent thing to do," Ebbets added. "You can get a very, very accurate orbit...predict years into the future whether it's on a collision course with us or not."
Long-delayed expectations
Along with the need to come to grips with scalawag asteroids that could harm Earth, SwRI's Chapman senses other NEO exploration outcomes.
"Though I am a space scientist strongly oriented toward the cost-effective robotic exploration of the solar system, I also grew up on science-fictional accounts of human expansion into the cosmos, and I endorse that more expensive - but ultimately inevitable - direction for human exploration," Chapman said.
Chapman said that it makes sense to him that NEOs could be used as "way-stations" to Mars. "Human visits to NEOs can go part-way toward understanding the challenges of going to Mars, yet not invoke the most serious challenges," he said.
Regarding concerns in some quarters that efforts to send humans to NEOs may be a distraction from the main, early focus of sending humans to the Moon, Chapman said: "In the current environment where the 'Vision' dominates NASA and the budget tends to restrict what we might do under the umbrella of the 'Vision' to the narrowest aspect of the 'Vision'...the focus must be on the Moon." More than the Moon
But Chapman continued by noting that the dreams of people worldwide who want to expand their long-delayed expectations of going into interplanetary space, NASA - assisted by the budgetary processes in the Congress - must find a way to do more than just return to the Moon.
"I happen to believe that scientific exploration of the Moon...could be extremely significant. And the Moon is much more easily explored and developed than Mars, which must remain a longer term challenge. But NEOs offer a special, practical, and inspiring challenge that we should keep on the table," Chapman explained to Space.com.
In the context of the hazard of destructive impacts by NEOs on the Earth, Chapman said that "everything we can learn about the physical nature of NEOs can incrementally enhance our chances of dealing effectively with one, should one be discovered that seriously affects us." He explained that robotic exploration of such a NEO would be essentially as good as human exploration of that threatening object.
"But the generic exploration of NEOs - even if solely in the goal of getting to Mars - can have side benefits not only for understanding the range of issues we might have in dealing with a threatening NEO, but also in learning how we might mine the resources of NEOs for future use in human exploration of the solar system," Chapman concluded.
The Cornishman Fri, 03 Aug 2007 10:40 EDT
Penwith's ufo mystery deepened this week as further sightings of "fiery" objects in the night skies emerged - including one close encounter captured on film.
Unidentified flying objects have now been spotted over three West Cornwall towns in the past fortnight.
First to be seen by an amazed witness in Hayle were "fiery red/orange" objects flying at high altitude.
Now it has emerged that he is not alone - with perhaps dozens of other people in St Ives and Penzance reporting similar incidents.
Laura Husband of St Ives contacted The Cornishman after reading last week's report of the Hayle sighting.
She claims her brother, James, recently had a similar experience in St Ives. Intriguingly, she may have seen the same thing in the same part of town - two years ago.
Laura, a holiday park receptionist, explained: "I saw a single fiery object exactly as described in last week's Cornishman article several years ago in St Ives.
"The memory of what I saw has stayed with me as I was so amazed. The week before this story was printed my brother came home and said I wouldn't believe him but he had just seen these strange fiery balls.
"I did believe him. He described exactly what I had seen and the stranger part was that he had seen them in exactly the same spot I had seen them a few years earlier."
Then, in a further twist, a work colleague of Laura revealed a friend had captured another UFO incident above Penzance's harbour area on their mobile phone's video camera.
"You can clearly see this fiery ball moving around un-like anything else.
"It bounces around just above the street lights, then, all of a sudden it appears to move away into the far distance at great speed.
"I think it's fascinating that there have been so many similar sightings of the same description around the same time of night.
"I'm keeping an open mind about what it might be but it's interesting that so many people are talking about seeing these similar-sounding objects."
Meanwhile, the Cornwall UFO Research Group is hoping to discover the truth about the sightings.
Founder David Gillham told The Cornishman West Cornwall appeared to be experiencing a spate of UFOs, and revealed further sightings had been reported at Sennen Cove and Porthcurno.
"There's a hell of a lot of people seeing these things at the moment," he said.
* The Cornwall UFO Research Group can be contacted on 01872 276381, or found online at www.cornwall- ufo.co.uk .
ELIZA STRICKLAND ABC News Sat, 04 Aug 2007 05:00 EDT
Former astronaut Rusty Schweickart has already earned his place in the history books by flying in space on the Apollo 9 mission. However, should an asteroid crash into the Earth anytime soon, killing millions and causing catastrophic damage, he'll also be remembered as the guy whose warnings we ignored.
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| ©AP |
In 2001 Schweickart, now 71, helped found the B612 Foundation (named for the asteroid home in The Little Prince) to raise the alarm about the potential of death from above. The foundation has been loudly asking the world's space agencies to locate all the near-Earth asteroids, determine if any are likely to crash into us, and make plans to deflect them if necessary. But NASA and the other agencies have taken little action. Wired News spoke to Schweickart about the importance and frustrations of his latest mission.
Wired News: You've devoted the last six years to warning people about the catastrophic possibility of a near-Earth asteroid crashing into the Earth. Does this stuff keep you awake at night?
Rusty Schweickart: (laughs) Does it keep me up at night? Yes, but not in the way you're probably asking. I don't stay up at night worrying about an impact. I do stay up and work over in my mind various technical issues, and think about the work that needs to be done.
WN: When did you first start thinking about the threat posed by near-Earth asteroids?
Schweickart: My interest came from my prior interest in astrobiology, which is the research field looking at the origins and extent of life in the universe. When you look at the origins and evolution of life on Earth, it's been severely affected by asteroid impacts through history. I came to the clear understanding that this is not a historical process, or something that is no longer in effect. It's a continuing process, and we're continually vulnerable to, essentially, a control-alt-delete.
Life has sustained a number of those hard boots, to continue the metaphor, the demise of the dinosaurs 65 million years ago being only the most recent example that people are aware of. But there have been very damaging impacts far smaller than the one that occurred 65 million years ago, and they are far more frequent. Those are of more concern to humanity, but they're also predictable. If we know that something is going to happen and there's something we can do about it, we ought to start getting prepared. WN: You were in the news a few years back talking about the asteroid 9942 Apophis, when it appeared there was a chance that it could hit the Earth in 2029 or 2036. That got some media attention, until further studies reduced the likelihood of impact to nearly zero. Were you relieved, or maybe a little disappointed that there was no urgent cause for action? Schweickart: When the probability of impact in 2029 dropped to zero, I think everyone was very relieved. There is still to this day a possibility of impact in 2036. It is quite low, and it will most likely drop to zero. But Apophis has been a tremendous learning opportunity for the (near-Earth asteroid) community. It exemplifies the kind of challenge we will encounter in the future. There will be tens of thousands of near-Earth asteroids discovered in the next 10 to 20 years.
WN: The Planetary Society is still offering a $50,000 prize for the best plan to put a tracking device on Apophis when it swings by in 2029. Although it appears that will be unnecessary, do you think the design contest still serves a purpose?
Schweickart: In responding to that challenge, there are probably teams of people learning a great deal. The possibility of Apophis continuing to be a real threat is one in 45,000. But in terms of understanding the challenge that we're going to be facing with other near-Earth asteroids that we find -- and we will definitely find some that will be more threatening -- it's very useful.
The more people we have thinking seriously about this, the better. And I'm not talking about the general public wringing their hands, I mean technically qualified people seriously looking at the challenge of taking action. It's important to have people studying the orbital mechanics, the techniques we could use for deflection, and looking at the decision-making process that would be involved in deciding which asteroids to deflect. The legal and political implications will probably be the most difficult challenges. WN: Why is that?
Schweickart: Who is it that makes the decision: Do we or do we not deflect this particular asteroid? Is it small enough that someone will say, "We'll just take this hit, we won't deflect this one"? If it's just going to impact a few counties, are they the only ones who pay for it? There are a million questions of that kind that will have to be answered, and not after we discover one that has our name on it, but before, so we don't end up in a decade-long debate when we're threatened.
Brent Whiting azcentral.com Sat, 04 Aug 2007 05:10 EDT
The unidentified flying object, described as a small rocket about two feet long and four inches in diameter, was reported over a Yavapai County neighborhood then landing near the Verde River.
However, searchers have combed the area southeast of Cottonwood and have found no evidence of any flying object, authorities said Friday.
"At this point, the search for the object has concluded," said Scott Reed, a spokesman for the Yavapai County Sheriff's Office.
The rocket sighting was reported by two residents who live on Hogan Lane in Bridgeport, a community between Cottonwood and Cornville, Reed said. The color of the rocket was not reported.
"There were no reports of other suspicious activity in the air," Reed said.
He said that people with information about model rockets being fired in the Bridgeport area are urged to phone Yavapai County sheriff's deputies at (928) 771-3260.
Deputies searched the area Thursday evening, then returned early Friday for another ground search along with helicopter support from the U.S. Forest Service, all with "negative" results, Reed said.
Officials at Luke Air Force Base were advised of the rocket sighting, but base officials have no information to shed light on the mystery, said Mary Jo May, a Luke spokeswoman.
Operations from Luke don't include flight patterns over the Cottonwood area, May said.
The Sunday Times Tue, 07 Aug 2007 16:26 EDT
It might have felt like an earthquake to Sydney coastal residents but it wasn't, scientists say.
Dozens of Sydney coastal residents reported their houses shaking this afternoon but Geoscience Australia said it was not an earthquake.
Residents reported windows shaking about 3.45pm (AEST) in the eastern beach suburbs of Maroubra, Clovelly, Bondi and Tamarama, a Geoscience Australia spokesman said.
"We're pretty happy to say that it wasn't an earthquake," the spokesman said.
"At this stage Geoscience Australia has not recorded any seismic activity. It would certainly have to be very, very small for us not to register it."
Radio talkback callers also reported several houses shaking on Sydney's north shore and northern beaches.
Kristen Philipkoski Wired Tue, 07 Aug 2007 16:58 EDT
On Friday Wired News profiled a "lonely" former astronaut, Rusty Schweickart, who is leading a campaign to protect the earth from the possibility of an asteroid crashing into Earth and killing millions of people.
Turns out he wasn't so lonely. While we said in the Q&A that NASA was doing little to protect us from an asteroid crash, it turns out the agency's been working on an anti-asteroid nuclear missile.
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| ©Flight |
NASA's Marshall Space Flight Center has designed a nuclear-warhead-carrying spacecraft, to be launched by the US agency's proposed 's Ares V cargo launch vehicle, to deflect an asteroid that could threaten all life on Earth.The 8.9m (29ft)-long "Cradle" spacecraft would carry six 1,500kg (3,300lb) missile-like interceptor vehicles that would carry one 1.2MT B83 nuclear warhead each, with a total mass of 11,035kg.
NASA says that by the 2020s, the interceptor will be able to detect a dangerous asteroid 5 years in advance, and deflect it two years in advance.
NASA Plans Armageddon Spacecraft to Blast Asteroid
Sydney Morning Herald Wed, 08 Aug 2007 06:37 EDT
For the first time, there is solid data to refute a popular theory that life came to Earth aboard a comet, Rutgers researchers say.
Deteriorated DNA from microbes, frozen for millions of years in the Antarctic ice, shows that organisms could not have survived the bombardment of cosmic radiation during deep space travel from outside the solar system, said Paul Falkowski, a Rutgers biologist and oceanographer.
"It's almost an impossibility for comets to seed other planets with life after they've been in space for millions of years," Falkowski said.
That's because genetic material is severely damaged or destroyed by exposure to so-called "cosmic radiation flux", he said.
Falkowski is co-director of the two-year study of frozen glacial microbes, conducted in conjunction with Boston University, and published in the Proceedings of the National Academy of Sciences.
The researchers were mainly interested in whether genetic material from the microbes, which they identified as different types of bacteria, could have mixed with that of other organisms in the Earth's ancient oceans, and influenced evolution, Falkowski said.
The Rutgers study refutes at least part of the "panspermia hypothesis" - a theory from the Greeks, and popular among many scientists since the 19th century - that micro-organisms and biochemicals were carried to the planet by comets, meteors and asteroids.
Other scientists in New Jersey said that they were intrigued by the Rutgers study, but suggested there might be ways some organic material could survive long-term rides on a comet.
"The only question I'd have is whether the radiation can penetrate into the interior of a comet," said Dale Gary, an astrophysicist at the New Jersey Institute of Technology in Newark.
Comets are called "dirty snowballs", which implies there is a certain amount of rocky material at their centre which could provide a shield for travelling DNA, Gary said.
"Certainly anything on the surface of comets would suffer radiation damage," he said. Gary, chairman of physics at NJIT, had not seen the study.
"Perhaps they (Rutgers) have done some calculation of the penetration of these cosmic rays through ice, and concluded that, for a certain radius, it can destroy DNA deep inside.
"However, we don't know everything there is to know about the interior of comets," he said. A large comet might have enough rock in its core "to keep DNA material rather pristine and safe", Gary said.
Radiation might be a problem for microbes, but not for very basic organic material, said Kevin Conod, an astronomer and manager of the Dreyfuss Planetarium at the Newark Museum.
"I think the theory of panspermia is not about microbes from space, but amino acids, the building blocks of life," Conod said. "Radiation wouldn't necessarily affect those enough to kill pieces of protein."
The Rutgers researchers thawed five microbial samples taken from ice between 100,000 years and eight million years old, and were able to grow several organisms in liquid media, said Kay Bidle, a Rutgers marine microbiologist and oceanographer.
They also wanted to know how long organisms could live over extended geologic periods, Bidle said.
"This is of interest to whether there is life on Mars," he said, as the site in Antarctica resembled icy regions on the Red Planet.
Microbes might survive a trip from Mars if encased in a meteorite, Falkowski of Rutgers said. "So we could all be Martians," he said.
Sanjeev Chopra Indian Express Newspapers Fri, 03 Aug 2007 10:49 EDT
Hotipur (Sangrur): This non-descript village near Khanauri today hit headlines when a meteorite fell in the fields on Wednesday night, leaving many villagers baffled. The police have taken possession of the 8-cm meteorite to hand it over to a three-member team of Geological Survey of India (GSI), led by a director-level officer, which is arriving tomorrow.
Curious villagers queued up in the fields of Pargat Singh to see the "heavenly object". While the farmer, who was the only witness to the fall of the "fireball", said, "I got scared of the big fireball that was coming my way at 8:45 pm on Wednesday night. I ran for cover as I felt that it will fall on me." "I rushed home and decided not to tell anyone about it. Yesterday morning, I gathered some courage and went to see the spot and found a rock-like object lying in the mud. It was then that I informed the villagers about it, who felt that it was a heavenly object."
There was no crater at the spot where the fireball fell. "Since all meteorites are the property of Geological Survey of India, we informed them and are now waiting for them to arrive," said Sangrur SSP Arun Pal Singh. The GSI team is likely to question the lone witness, Pargat Singh.
Meanwhile, a much sought-after Pargat was busy guiding curious onlookers to his field with pride and giving interviews to a host of TV channels.
Sahara Samay Wed, 08 Aug 2007 20:11 EDT
Jaipur, India - A family in Jaipur told the scientists of Geological Survey of India (GSI) here that a meteorite fell in the courtyard of their home on Monday evening, Sahara Samay sources said.
A female member of the family told that a piece of sparkling stone fell in her home on Monday evening. I continued to look at it in awe for sometime before I went near it, she added.
However, the scientists of Geological Survey of India have said that the piece of sparkling stone does not appear to a meteorite. Even a meteorite of small size can cause a big damage, said Dinkar Srivastava, a scientist.
He said that the speed of meteorite is several thousand kilometres per second and even a small meteorite is usually bigger in size than the one found in a home here.
He further added that the GSI could be able to say anything only after testing the piece of stone or meteorite.
It is worth noting here a similar sparkling stone was found in a village in Sangrur district of Punjab a couple of days ago.
Beth Duckett The Arizona Repulic Thu, 09 Aug 2007 22:33 EDT
SCOTTSDALE - Stanley Fosha is looking for what woke him early Wednesday morning with a giant flash of white light and a thunderous boom.
The sky erupted around 2:15 a.m. near his home at 56th Street and Pinnacle Vista Road in Scottsdale, he said.
"I seriously thought someone was in my back yard taking a picture," Fosha said. "It sounded like someone taking a sledgehammer and banging a big metal drum."
Worried he imagined the light, Fosha asked his neighbor Tami Biggs about it the next day.
Biggs said she saw it, too.
"I was outside saying goodbye to some friends. It was a big, bright light and a loud bang," said Biggs, who lives two doors away from Fosha. "It certainly caught our attention."
So what exactly was this unidentified burning object?
A bolide, predicts Prof. Jeff Hester with the Arizona State University School of Earth and Space Exploration.
Bolides, or large meteoritic fireballs descending from the sky, are known to hit ground on occasion, Hester said.
In fact, he has seen a few himself.
"They are just spectacular, remarkable things," Hester said. "They can literally explode."
And this bolide made its entrance just days before the annual Perseid shower is expected to peak.
Hester said it is on Sunday this year.
Though likely not as large as Fosha's sighting, the meteors should be pretty plentiful, he said. And with a new moon on Sunday, it also should be a pretty clear show.
The shower, best viewed after 11 p.m. and before dawn, boasts its greatest activity between August 8 and 14, he said.
The key is getting away from city lights, Hester said.
"Then you just lay back and let your eyes adapt to the dark and relax," he said. "You might see as many, on average, as every minute or so."
The Perseids are dubbed after the constellation Perseus, where most of them appear to originate, he said.
They are remnants of a debris path left by the comet Swift-Tuttle.
"You get a meteor shower when the earth passes through these debris paths," Hester said. "When comets come in close to the sun, the sun causes the surface to sublime and a bunch of dust is blown off into interplanetary space."
Don't expect to see the comet anytime soon. Swift-Tuttle only shows up once every 133 years, Hester said.
All Hungary News Fri, 10 Aug 2007 11:07 EDT
The southern Transdanubia area of Hungary at the border of Tolna County was shaken by the sound of an explosion Sunday afternoon when a melon-sized meteor apparently hit the ground in Bonyh?d. Astronomers are analyzing the impact crater, which is two meters deep and seven meters in diameter, reports fn.hu.
Istv?n Tepliczky, secretary of The Hungarian Astronomical Association (Magyar Csillag?szati Egyes?lt), said by analyzing the impact marks they concluded that the angle of the meteor made it impossible for people to see, since it came from the west in the exact angle of the setting sun.
Until the analysis is finished, it cannot be confirmed a meteor crashed into Hungary. Tepliczky mentioned that the left side of the crater was slightly above the right side, which proves the impact of an object coming from the west.
"Meteor striking is a very rare phenomenon in the Earth, even though we can find clues in the Solar system," said Szaniszl? B?rczi, professor at ELTE University Department of Materials Physics. "Other planets show shapes caused by cosmic impacts and the crater found at the border of Bonyh?d shows a similar one."
The speed of the meteor was an estimated 10km/sec and the power of the impact destroyed it; meteorites typically evaporate and dissolve into the ground after impact. The meteorite itself won't be found, but its substance can be detected in the sample taken from the ground.
Comment: A couple of points about this incident:
1. If you are a regular reader of these pages, you know that a meteor striking the Earth is not as uncommon as it once was...
2. No one saw it because it came from the west during the setting of the sun. Think about that one for a minute....
Stephen Battersby NewScientist.com Wed, 08 Aug 2007 19:55 EDT
A rare meteor shower predicted to hit Earth on 1 September should give astronomers only their second chance to study an ancient comet's crust. It could also help them develop a warning system against an otherwise insidious threat - a comet aimed at Earth from the dark fringes of the solar system.
September's shower, called the alpha Aurigids, has only been seen three times before, in 1935, 1986 and 1994. The reason for this elusiveness is the shower's unusual origin.
Most meteor showers are caused by short-period comets, dirty iceballs that loop around the inner solar system on orbits lasting less than 200 years, shedding debris each time they approach the Sun's heat. This debris builds up into a broad band along the comet's orbit. Every year, when we pass through, it burns up in the atmosphere and appears as shooting stars.
The Aurigids come from a comet that takes 2000 years to orbit the Sun. With such infrequent visits, Comet Kiess can't build up a broad dust band; it only generates a narrow trail of debris each time.
The showers happen when Earth passes through one of these dust trails in particular, which was thrown off by the comet in 83 BC. "It is only a very narrow trail, and it is only once in a while that it crosses Earth's path," says Peter Jenniskens of NASA's Ames Research Center in Moffett Field, California, US.
He thinks the gravity of Jupiter and Saturn controls the path of the dust trail, waving it around like a garden hose, occasionally aiming it at Earth. Along with his colleague J?r?mie Vaubaillon at Caltech, US, Jenniskens has calculated that the hose should be pointed at us again this year.
Hard crust
Several teams of astronomers will be watching the shower, both from the ground and from two aircraft following the Earth's shadow.
They are hoping to see fragments of the ancient crust of Comet Kiess. For 4.5 billion years before some gravitational accident nudged it towards the inner solar system, Kiess was drifting among a vast swarm of icy bodies called the Oort cloud lying far beyond the planets.
All that time, high-energy particles called cosmic rays bombarded the comet, and astronomers suspect that created a hard crust by blasting out some of its more volatile substances.
Only once before have astronomers knowingly seen a shower from a long-period comet, when Jenniskens predicted an appearance of the alpha Monocerotids in 1995. They penetrated unusually far into the atmosphere, suggesting that they were made of relatively tough material, perhaps from such a cosmic-ray-produced crust.
This time, astronomers will be looking at the spectral signature of evaporating meteors to test this theory. "Now we are better prepared, we can do more in-depth studies to understand the properties of the material," Jenniskens told New Scientist.
Contribute observations
He also wants to know whether meteor showers such as this could warn of planetary peril. At present, astronomers can only spot a long-period comet a few years before it arrives in the inner solar system, leaving little time to deflect it if it were pointed right at Earth.
But if it had visited the inner solar system before, the resulting meteor shower might be used to trace the comet's orbit and get a much earlier warning. The size and number of Aurigid meteors will tell the researchers how debris has spread along the orbit and how these showers evolve.
They are keen for amateurs to contribute their observations. "We're interested to know what is the brightest, biggest Aurigid," says Jenniskens. "Somebody is going to capture that, and it's probably not going to be us."
The best view of the meteors will be from the west coast of North America, before dawn on 1 September. Based on past showers, there should be up to 200 bright meteors visible per hour, and they may have an unusual blue-green colour.
The shower probably won't return for at least 50 years, according to Jenniskens' calculations. "It's a once in a lifetime event."
BJ Hansen MyMotherLode.com Sat, 11 Aug 2007 19:51 EDT
Sonora - Representatives with the Sonora Police Department and both the Tuolumne and Calaveras County Sheriff's Departments say they fielded numerous calls early this morning in regards to a "loud boom," and "structures shaking."
According to a Sonora Police Department report, there were several calls from residents who reported seeing "a blue light," just before the "loud boom." The incident reportedly occurred at 12:09am. The Police Department notes that it also received a call from a resident in Tuolumne, in which a female reported seeing what she thought was fireworks, and then something spiraling over her house.
Early indication from the law enforcement agencies is that the loud boom was somehow the result of a meteor shower.
Comment: "somehow the result of a meteor shower" - this isn't a meteor shower:
A "meteor shower," also known as a "meteor storm," is a celestial event where a large number of meteors are seen within a very short period of time. These meteors are small fragments of cosmic debris entering Earth's atmosphere at extremely high speed, leaving a streak of light that very quickly disappears. Most of the small fragments of cosmic debris are smaller than a grain of sand, so almost all fragments are burnt up and never hit the earth's surface. Fragments which do contact earth's surface are called meteorites
The description from the article is of a possible bolide entering and then exploding either in the atmosphere or on the surface of the earth, which causes structures to shake.
AFP Sun, 12 Aug 2007 13:46 EDT
Russian police were combing the northern Siberian city of Krasnoyarsk on Friday for a three-tonne meteorite that has disappeared from under the nose of its keepers.
The giant rock was stolen from the yard of the Tunguska Space Event foundation, whose director said it was the part of meteor that caused a massive explosion in Siberia in 1908, news agency Interfax reported.
"It winds up that it disappeared back in June, when the foundation was moving out of its old building," a police spokesman told the agency.
"Our colleagues are establishing what got lost, where the rock is and why they only came to us about it now," he said.
Foundation director Yury Lavbin brought the three-tonne rock to Krasnoyarsk after an 2004 expedition to the site of the so-called "Tunguska event" -- a mysterious mid-air explosion in Siberia in 1908 that was 1,000 times more powerful than the nuclear bomb dropped on Hiroshima in 1945.
Lavbin claimed at the time to have discovered the wreckage of an alien spacecraft during the expedition.
Scientists continue to argue over the cause of the explosion, which flattened over 2,000 square kilometres (800 square miles) of Siberian forest.
Kelly Beatty SkyandTelescope.com Mon, 13 Aug 2007 12:16 EDT
Here at Sky & Telescope we get wind of all kinds of reports of meteorite falls. Few are legitimate. But on July 6th the sky really was falling over South America, when an incoming object broke apart in the lower atmosphere with a trio of ferocious explosions that shattered windows and shook the ground violently. Moments later, stones rained from the sky and pelted homes in the poor barrios surrounding the notorious city of Cali, Colombia.
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| ©Michael Farmer |
Nothing gets the adrenaline of meteorite collectors rushing like a fresh fall, and it wasn't long before Michael Farmer and Robert Ward flew south from Tucson, Arizona, in search of cosmic treasure. After reaching Colombia, they teamed up with local amateur astronomers and headed into the barrios to try to recover some of the fragments.
After a few days of searching, they'd rounded up and purchased several small pieces - some of which had smashed through the roofs of homes - totaling about 270 grams (10 ounces).
But not all of their exchanges with the locals were pleasant, as word got out that some gringos with money were in the area. Farmer explains:
"As we tried to drive through a barrio just near where one of the stones was found, a man ran at our taxi with a large gun screaming at us to stop. I saw the people in the front of the taxi duck down and then saw the gunman running at us. The driver hit the gas and we swerved around him, but the gun was about 1 meter from my head. He did not fire, thank God, but what a scare!"
Now safely back in Tucson, Farmer estimates that the Cali event must have dropped fragments far more massive than what he and Ward were able to collect. Unfortunately, it all ended up in dense cane fields and will never be found. And although the recovered "hammer stones" turned out to be a rather common type of chondritic (rocky) meteorite, they're already fetching thousands of dollars per gram among meteoritic aficionados.
Comment: For more information that was collected on this meteorite event go to this link
KLTV7 Mon, 13 Aug 2007 13:32 EDT
"It was big... It was huge in the sky, " Cynthia Costello says.
Cynthia Costello is no stranger to meteor showers in shingle springs this time of year... But nothing prepared her for what she saw overnight.
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| ©KLTV7 |
Cynthia says "It looked like kind of flashes for a little bit for just a couple seconds and then it was just a big burst and it startled me so bad... And said did you see that and he huh... He was asleep."
She's convinced the explosion in the sky was a meteor.
Cynthia says "it looked kind of like lighting but confined in a spherical type... It was very, very, bright, brighter than lighting... Cause it lit up the whole backyard and lit up the inside of the house.... It was like two seconds max."
Costello soon found out she's not the only one who caught the night show.
Cynthia says "I figured i'll call in the morning to see if something happened, and they said we are not sure what it is but we are looking into it."
We sent the e-mails to the discovery museum in sacrmento. Judy Pischalnikoff shares her opinion as a space educator.
Judy says "I would call it a meteor but not part of the meteor shower. Because it was so huge."
While space educators say this video was likely of a meteor, they have no way of knowing if it hit the ground like this meteorite that fell long ago in Arizona. It's believed other pictures sent in are of space debris. If you missed the show last night, not to worry. Meteor showers can be seen in the sky for the next week.
Comment: To see the news report that shows the video of the meteorite from the picture above watch Mysterious Object Seen In Sky
Also, this meteorite may be related to this story "Loud Boom" Believed To Be The Result Of Meteor Shower - California
Cheryl Dybas National Science Foundation Tue, 14 Aug 2007 03:54 EDT
New scientific findings suggest that a large comet may have exploded over North America 12,900 years ago, explaining riddles that scientists have wrestled with for decades, including an abrupt cooling of much of the planet and the extinction of large mammals.
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| ©Allen West, UCSB |
| A "black mat" of algal growth in Arizona marks a line of extinction at 12,900 years ago; Clovis points and mammoth skeletons were found at the line but not above it. |
The discovery was made by scientists from the University of California at Santa Barbara and their colleagues. James Kennett, a paleoceanographer at the university, said that the discovery may explain some of the highly debated geologic controversies of recent decades.
The period in question is called the Younger Dryas, an interval of abrupt cooling that lasted for about 1,000 years and occurred at the beginning of an inter-glacial warm period. Evidence for the temperature change is recorded in marine sediments and ice cores.
According to the scientists, the comet before fragmentation must have been about four kilometers across, and either exploded in the atmosphere or had fragments hit the Laurentide ice sheet in the northeastern North America.
Wildfires across the continent would have resulted from the fiery impact, killing off vegetation that was the food supply of many of larger mammals like the woolly mammoths, causing them to go extinct.
Since the Clovis people of North America hunted the mammoths as a major source of their food, they too would have been affected by the impact. Their culture eventually died out. The scientific team visited more than a dozen archaeological sites in North America, where they found high concentrations of iridium, an element that is rare on Earth, and is almost exclusively associated with extraterrestrial objects such as comets and meteorites.
They also found metallic microspherules in the comet fragments; these microspherules contained nano-diamonds. The comet also carried carbon molecules called fullerenes (buckyballs), with gases trapped inside that indicated an extraterrestrial origin.
The team concluded that the impact of the comet likely destabilized a large portion of the Laurentide ice sheet, causing a high volume of freshwater to flow into the north Atlantic and Arctic Oceans.
"This, in turn, would have caused a major disruption of the ocean's circulation, leading to a cooler atmosphere and the glaciation of the Younger Dryas period," said Kennett. "We found evidence of the impact as far west as the Santa Barbara Channel Islands."
NSF's Paleoclimate Program funded the research.
Kevin Krajick Popular Science Fri, 17 Aug 2007 13:23 EDT
A recent study showed that the U.S. and China are the nations most vulnerable to a devastating meteorite strike. With funding uncertain, astronomers are struggling to contain the threat of a civilization-ending galactic visitor.
What's Out There
There are between one and two million near-Earth objects (NEOs) - chunks of space rock whose orbits may pass within 30 million miles of Earth - that pose a significant impact threat to the planet. Of the 4,535 NEOs detected and tracked (704 of which are real whoppers), none are on a definite collision course, but there could be millions more, many of them potentially lethal, lurking in the cosmos.
Detection
Who's Watching? Most spotting is done by half a dozen optical telescopes in the U.S., Italy, Japan and Australia, coordinated by such programs as the Lincoln Near-Earth Asteroid Research (LINEAR) project, a NASA-funded collaboration between MIT's Lincoln Laboratory and the U.S. Air Force tasked solely with the detection and cataloging of potential NEOs. Amateur astronomers worldwide also aid the effort. Collectively, the programs discover a new NEO every few days.
What's the Plan? Since 1998, NASA has funded Spaceguard, a consortium of observatories working to find 90 percent of the half-mile-plus NEOs by 2008; the group has found three quarters of the predicted 1,100 NEOs in this size class. Spaceguard's next step is to find 90 percent of NEOs measuring 460 feet or larger - potentially up to 12,000 objects - by 2020, but funding has not been secured. Larger wide-field scopes should come online in Hawaii, Arizona and Chile in the next decade, greatly speeding detection.
The Hot List NASA's NEO office maintains a watch list of about 140 especially high-risk asteroids. The baddest asteroid so far is 820-foot-wide 99942 Apophis. Discovered in 2004, it briefly presented a 1-in-38 chance of collision on April 13, 2029. As more data helped scientists to pinpoint its orbit, Apophis has since been downgraded to 1 in 45,000 in 2036 - still the biggest collision threat in the known universe.
Deflection
A handful of scientists, both at NASA and the privately funded B612 Foundation, have proposed various protocols for diverting or destroying a collision-course NEO. None currently have funding, although the asteroid fly-by mission Dawn will launch this month. And NASA has looked into using existing rocket and spacecraft technology to land an astronaut on an asteroid, a move that, if successful, could help hone future deflection strategies. Here, a few plans on how to save the planet.
Nuke It We already have the bombs, but the risk is that an explosion could turn one killer asteroid into many smaller killer asteroids, thrown into unpredictable trajectories - and radioactive.
Smack It A spacecraft would ram the object, altering its orbit or shattering it. Elegant, but could multiply the threats as with the bomb scenario above.
Lean On It A craft would push or pull the object. Not sideways - too energy-intensive - but backward or forward to slow it down or speed it up. A few pounds of force applied over several months would alter a medium-size body's rate of travel such that it would miss hitting Earth by four or five minutes and thousands of miles. An asteroid tugboat would attach to a NEO and deliver a speed-altering nudge. A gravity tractor would hover close to a NEO and use mutual gravitational attraction to divert it ever so slightly. A solar sail would move a NEO with the subtle pressure of light from the sun.
forgetomori Fri, 17 Aug 2007 13:34 EDT
Following the terrible natural disaster on Peru, which caused hundreds of casualties, some local news agencies are also speaking about reports from locals of flashes of light in the sky both before and after the event.
According to El Comercio from Peru,
"During the night ... before and after the stron earthquake, neighbours from the districts of Miraflores, La Molina and Cercado de Lima assured having seen the sky light up because of an unexpected lightning in the middle of the night. Nevertheless, the National Hydrology and Meteorology told El Comercio that it didn't detect any anomaly in Lima's skies, and assured that this phenomenon could have been caused by the light of a beacon or some spinning panels that exist in the city".
Over at MarcianitosVerdes, Luis Ruiz Noguez is receiving and collecting more reports from multiple witnesses who also claim to have seen the lights. Noguez prudently warns that before speculating if the incidents were indeed earthquake lights, the prosaic explanations must be ruled out first.
The video above, posted on Marcianitos, is allegedly of one of the incidents. It was suggested to Noguez, and has been also featured over at this blog, that suggests it's triboluminescence.
I think the point of light that can be seen in the video along with the flash is from a conventional source (an emergency light), maybe it's the same point of light that can be seen before the blackout. But the flash of light itself must have been indeed intense, and as there's no sound along with it, and apparently the local institutions did not report any weather anomaly, it may possibly be the record of an earth light.
For those who don't know about it, there's a quick summary about earthlights. In Spanish, MarcianitosVerdes have in-depth dossiers on the subjects - one of the reasons people looking for more info on Google ended up finding his excellent blog: Las luces de los terremotos.
Update: Marcianitos just posted another video:
Several flashes, including a big one around 40 seconds after the video starts, can be seen over the horizon. Noguez remarks once again that it must be verified if they weren't explosions from the power transmission lines and transformers.
According to the reports the flashes were not accompanied by any sounds, and some say they originated in the sea. As we all know, light travels a lot faster and farther than sound, so explosions on one place could have been noticed as just lights from far away.
But at first glance, the flashes are so bright that one suspects that if they had conventional causes, then even if the sound was not heard, the causes would be quickly pointed to their origins, as the explosions themselves may have been quite significant, probably injuring or killing people.
There still seems to be much confusion, and the Peruvians need more urgent help and solidarity for their death and injured. Which also doesn't mean we should ignore the possibility of so many records and reports of what may have been a poorly understood phenomenon associated with earthquakes.
We follow all the news with great interest and hope for the best. Check Marcianitos in Spanish for the latest updates.
UPDATE: Check the latest post on the subject, Earthquake lights or Electrical transformers? The answer seems to be electrical transformers, though there may still have been erthquake lights involved.
Tim Moran Modesto Bee Wed, 22 Aug 2007 17:24 EDT
Corrina Vargas, 26, was cooking breakfast in her mother's neighborhood home Monday morning when she heard an explosion.
Her son, Carlos Mendez, 10, was sitting on a bed in the living room watching cartoons when something came through the roof. A small piece of the debris hit him in the back of the head.
They ran outside, and Vargas' mother, Mary Montano, gathered the rest of the adults and children in the house and got them out.
No one was hurt by what turned out to be a bowling ball-sized chunk of ice that crashed through the roof. The hole in the roof appeared to be two to three feet wide.
Police spokesman Sgt. Craig Gundlach said investigators were not sure where the ice came from, but it may have dropped from a commercial airliner.
"We are in contact with the (Federal Aviation Administration), and they are not aware of where it could have come from," Gundlach said. "There is no indication it was anything but an accident."
FAA spokesman Ian Gregor said investigators were en route to Modesto to examine the ice and try to determine where it came from.
It may be "blue ice" that leaked from an aircraft, Gregor said. Airplane bathrooms can sometimes leak, and the effluent, containing human waste, forms a chunk of ice outside the plane, Gregor said.
It is frequently blue because of the blue liquid used to flush toilets in planes. The air at the altitude airliners fly can be 50 degrees below zero, Gregor said.
When the airplane descends, the ice thaws and sometimes falls off the plane, he said.
Falling blue ice from airplanes is reported around the country from time to time. An incident was reported a few months ago in Ontario, Calif. east of Los Angeles, Gregor said.
How often blue ice falls from airplanes is difficult to track, because if the ice doesn't hit a home or damage anything, no one would know, Gregor said.
"It's not common, but it's not unheard of," he said.
Some commercial planes are prone to bathroom leakage, according to a 2004 FAA directive. Several models of the Boeing 737 are required to undergo repetitive leak checks and bathroom maintenance.
Modesto is under the flight path of airliners coming into San Francisco International Airport, Gregor said. The planes are at a little more than 20,000 feet when they pass over, he said.
Gundlach said the ice didn't appear to have come from a low-flying plane arriving or leaving Modesto Airport, which is across the street from the house.
If it were from an airplane flying at 20,000 feet, a chunk of ice that size could reach a speed of 120 to 200 mph, according to Joseph Alward, a physics professor at University of the Pacific. Alward estimated that the ice chunk may have been traveling at 160 mph.
The ice chunk hit the house with explosive force, according to Vargas.
"It was just a big old boom, and all that debris," she said. "I was just stunned. I thought it was a fire from the water heater."
There were four adults and five children inside when the ice hit it, Gundlach said.
The ice punched a sizable hole in the roof, broke through a roof truss and continued through the living room ceiling, he said. Had it not shattered as it penetrated the home, it would have landed about a foot from where Carlos Mendez was sitting, Gundlach said.
"With the velocity that chunk of ice had, we are very lucky no one was severely injured or killed," he said.
Firefighters said the fragments were brown and white, and looked like dirty ice. They found two brick-shaped chunks and lots of smaller shards.
Gundlach said evidence would be turned over to the FAA.
There is a possibility that the ice chunk wasn't from a plane.
Several incidents have been reported around the world of large chunks of ice falling to the ground that are apparently unrelated to airliners.
Jeszs Martmnez-Frias, a Spanish geologist, thinks the ice may form in the atmosphere, similar to the way hailstones are created.
He coined the term "megacryometeors" for the ice chunks. His hypothesis is controversial, however. Other scientists question whether ice chunks that large could be formed in that way.
FAA investigators may know more in the next few days, Gregor said.
Science Daily Thu, 23 Aug 2007 04:26 EDT
The space-borne infrared observatory AKARI, observed asteroid Itokawa last month with its Infrared Camera. The data will be used to refine estimates of sizes of potentially hazardous asteroids in the future.
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| ©JAXA |
| The asteroid Itokawa was observed by the Infrared Camera (IRC) onboard AKARI at 7 micrometres on 26 July 2007. The above image is a composite of three images from the data showing the motion of Itokawa over 12 minutes. The image covers an area of roughly 7.4 arcminutes x 7.4 arcminutes around the target. The Hayabusa spacecraft itself was too faint to be detected. |
The data collected by AKARI, a JAXA mission with ESA participation, complements that from JAXA's asteroid explorer Hayabusa in late April this year.
As AKARI observed Itokawa on 26 July it was in the constellation of Scorpius, and was about 19 magnitudes bright in visible light. The asteroid and Earth were closest to each other, at a distance of about 42 million km (for comparison, Earth is 150 million km from the Sun). Given how close it was, Itokawa moved a significant distance on the sky over the short observing time.
Using observational data of asteroids such as Itokawa in combination with data from the explorer, models that estimate asteroid sizes can be made more accurate. This is especially useful for estimating the size of potentially hazardous asteroids which may be discovered in the future.
Before Hayabusa arrived at Itokawa, many observations to determine the asteroid's approximate size had already been attempted. Among the many different methods of measurement, the most accurate estimate was achieved by mid-infrared observations.
With AKARI, it was possible to observe Itokawa at several different wavelengths in the mid-infrared range, obtaining a much more comprehensive set of data. This data is very important, not only for the study of the asteroid's infrared properties, but also for use as a template and source of comparison with other asteroids, to improve the estimates of their sizes.
Most sunlight falling on Itokawa is absorbed, heating the asteroid up. It then re-emits this energy as bright infrared light, which was in turn observed by AKARI. Only a small fraction of the incident sunlight is reflected from Itokawa, making it a very faint object when observed in visible light. It is very hard to observe using telescopes of sizes similar to that of AKARI from ground.
Asteroid size is one of the most sought-after pieces of information. For asteroids that are not explored directly, their sizes can be estimated based on various observations from Earth. The temperature of asteroids is determined by the balance between the energy input from incident sunlight, and the output, emitted as infrared radiation.
Existing computer models estimate the temperature distribution in asteroids by considering their shape, rotational motion, and surface conditions.
Observational data in the mid-infrared gives information on the infrared light emitted by the asteroid. Asteroid size can be derived by comparing observational data in the mid-infrared, with that expected from the calculations of the model. The models can further be improved by using the infrared observational data of well-studied asteroids, such as Itokawa.
AKARI has also made observations of possible candidates for future asteroid exploration. It is expected that this detailed information will help greatly further our knowledge of these interesting relics of our Solar System.
Note: This story has been adapted from a news release issued by European Space Agency.
Richard Edmondson stuff.com.nz Wed, 29 Aug 2007 13:04 EDT
A mysterious object seen in skies over the Tasman Sea near Kaitaia is baffling UFO experts.
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| ©W FERGUSSON |
| Disc-like: The object's shape suggests a circular 'something' with a dome-like top says world UFO expert Dr Bruce Maccabee. |
Last month, The Northern News reported that UFO Focus New Zealand (UFOCUS NZ) and world UFO expert Dr Bruce Maccabee were studying a series of unusual photographs taken at Ahipara on April 28.
The digital photos, taken of the sky and sea at 5.42pm, showed a bright object which did not look like a cloud and had the appearance of a craft.
The story attracted intense interest and remained one of the most viewed stories on the Northland page of the Stuff news website three weeks after publication.
Last week, UFOCUS released its report on the sighting and we can now bring you photos.
The report says the photographer watched the object for nearly five minutes while it moved silently across the sky in a northerly direction reducing in size and disappearing.
Dr Maccabee, an optical physicist in the United States Navy, says in the report that the object does not display flight characteristics that distinguish it as a 'craft' of unknown origin.
However, its shape suggests a circular 'something' with a dome-like top.
The object could also be a jet aircraft's vapour trail viewed end on, he says.
Air Traffic Control says there were no scheduled flights in the area at the time.
It would expect to see consistency of shape from both trails and a 'flow-off' similar to a cirrus cloud blown by winds if the object was a jet contrail.
Instead, the shapes in the photos are compact.
UFOCUS has consulted the Carter Observatory and ruled out the object being space junk or a meteorite, says the group's coordinator Suzy Hansen.
"Neither space junk nor a meteorite would present the images we have. They would be a ball of fire burning up rather than a bright object."
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| ©W FERGUSSON |
| Unexplained: UFO experts are classifying an object captured in photos taken at Ahipara in April as an 'unusual aerial phenomenon' or UAP. |
Dr Maccabee has not commented on whether the photographer may have manipulated the eight photos, says Ms Hansen.
While the UFO group cannot rule out the possibility of manipulation, she thinks it is unlikely the photos are a hoax.
"I have directly asked the witness if he hoaxed the photos, and he was most adamant that he had not.
"When you see the full series, you will see that it would take hours and hours to hoax such a thing."
UFOCUS and Dr Maccabee have agreed that no firm conclusion can be drawn about what the object is, says Ms Hansen.
They are classifying it as an unusual aerial phenomenon - UAP - but are keen to know what the public thinks it may be.
Peter Jenniskens, Ph.D., Meteor Astronomer, Carl Sagan Center, SETI Institute Space.com Thu, 23 Aug 2007 04:13 EDT
The meteors that are about to rain down in the early morning of September 1 date from around 4 A.D., the latest calculations show.
It is not often that we can tell when a shooting star was first released from a comet into space, to travel as a meteoroid in an orbit around the Sun, and finally collide with Earth's atmosphere to shine as a meteor for our enjoyment. Most meteors that sporadically flash across the sky on a dark moonless night date from anonymous times. Only in recent years have we learned to trace young meteor showers, just a few revolutions old, to their date of origin.
The oldest such shower, but only one revolution old, is due in the early morning of September 1, 2007. Our calculations indicate Earth is about to cross the dust trail of comet Kiess, a comet that takes some 2000 years to complete one orbit around the Sun. The trail is very narrow, so Earth will be hosed by meteoroids for only about an hour and a half. The meteoroids will approach from the direction of the constellation Auriga, the charioteer, in the north-eastern part of the sky, causing a meteor shower called the "Aurigids."
If you spot one of those meteors, you may be only the fourth person alive who is known to have seen this meteor shower. In recent times, the shower was spotted in 1994 by two observers and in 1986 by one observer.
If you are lucky enough to catch a picture of an Aurigid meteor using your digital camera, you will be the very first to do so.
Tips on how to observe meteors and where to report the results can be found at: http://aurigid.seti.org
The shower is visible from only part of the world. If you live in the western parts of the USA, Canada and Mexico, including Hawaii and Alaska, you might spot an Aurigid meteor. Plan to step out around 4 A.M. PDT in the early morning, warmly dressed with a blanket wrapped around your shoulders, away from city smog, with the Moon behind an obstruction, and with a wide view on the sky. Gaze up at the sky, waiting, and you may spot one of these elusive bits of matter that Comet Kiess lost 2000 years ago.
This is your only chance to see this shower; the dust trail is not going to hit again in our lifetime. It is also our best chance yet to test meteor shower prediction models and look for evidence of the crust that a comet is suspected to build up during the time it spends in the Oort cloud. Comets in shorter orbits have long lost this pristine crust.
Jon Giorgini of JPL/Caltech has identified observations of Comet Kiess when it returned in 1911. The orbit is now better determined than before and calculating backwards in time puts the comet near Earth's orbit in 4 A.D., give or take 40 years. It was at that time that the dust was released that we now see as meteors. The dust was ejected in wider orbits than the comet and took somewhat longer to return.
Jeremie Vaubaillon of Caltech calculated where the dust would end up at Earth's orbit on September 1, 2007, if it was ejected in 4 A.D. and he found that, indeed, the dust trail will be in Earth's path. The peak is expected at 11:33 UT, or 4:33 a.m. PDT, give or take 20 minutes.
From past Aurigid showers, we anticipate a shower of mostly -2 to +3 magnitude meteors with a peak Zenith Hourly Rate about 200 per hour during a 10-minute interval, with rates above 100 per hour for only 25 minutes. With a bright Moon in the sky, only 4 days past full, that translates to several tens of chances to make a wish on a meteor from around 4 A.D.
To increase our chances of catching these rare meteors, we will be observing the shower from two Gulfstream GV aircraft (flying at 45,000 ft) on a parallel flight path from Wisconsin, over the Bay Area in California, and on to the Pacific in the early morning of September 1. An international team of 24 researchers will have 21 windows to aim their cameras through. The cameras are of different types, some similar to your own digital camera and camcorder, others using technologies more familiar to cameras used on astronomical telescopes or those in night vision goggles. Near the horizon, we hope to see many more meteors than will be visible from the ground, but each of us will be glad if the shower actually shows.
You can participate in this research by making an effort to photograph or film the Aurigid meteors. Chances are that one of you, not us, will catch the brightest Aurigid out there. Even simple cameras can provide information about how the meteoroids break apart, as each image is composed of three different images: one in blue light, another in green, and one in red. Each color traces different aspects of the meteor's light.
More information at our Aurigid Multi-Instrument Aircraft Campaign mission website: http://aurigid.seti.org
international.news.bg Tue, 28 Aug 2007 18:37 EDT
The Center for small objects in the Solar system in Harvard, USA, acknowledged the three new asteroids found last week by Bulgarian astronomers in the Capricorn constellation.
This announced the University center on space research and technologies at the Physics faculty of Sofia University "St. Kliment Ohridski", cited by Darik radio.
The objects are temporarily labeled as 2007 PN28, 2007 PQ2 ? 2007 QD2 and are situated in the main asteroid zone. They circle between the orbits of Mars and Jupiter with periods respectively 4.7, 3.6 and 5.4 years.
In 2005 the Bulgarian astronomers found the asteroid 2005UT12, which was the first since 18 years, noticed by Bulgarians.
Since then despite the lack of state funding the young scientists have found seven space objects.
At the moment the astronomers from the observatory "Star society - MPC A76" and their colleagues from the national observatory "Rojen" conduct additional observations for specifying the characteristics of the new objects.
The team, which made the discoveries includes E. Mihaylova, Ch. Kaldiev and their supervisors F. Fratev and Ya. Shopov.
Philip Bradfield Belfast Today Tue, 28 Aug 2007 21:14 EDT
The mystery of what caused a sonic boom-like noise over Co Down has deepened after the RAF denied reports a supersonic fighter jet was in Ulster skies at the time.
Residents in north Down were alarmed when they heard what they thought was an earthquake on Tuesday afternoon.
News Letter journalist Lesley Walsh was at her Bangor home just after 3pm.
"It lasted for about three seconds and I felt it right through me," she said. "It shook the decking outside, reverberating right through it.
I was on the phone to a friend a mile away and she heard it too.
"At one point I thought it was a bomb, then maybe an earth tremor.
"It was not like ordinary thunder, it was a palpable noise. It was an absolutely perfect blue sky and I could see nothing overhead."
Police said it was "believed to be the sonic boom of a low-flying aircraft", adding their information came from the Coastguard.
However, the George Best Belfast City Airport could offer no explanation for the incident.
Yesterday, a Coastguard spokesman who also lives in Bangor, said he too heard the sound. "I was in my garden and my dog bolted when we heard the noise," he said. "It was like thunder but there was not a cloud in the sky. It was a strange sound."
He said the PSNI also had reports of the noise from Portavogie and that the RAF in Scotland had said it was a supersonic Typhoon fighter jet.
"RAF Kinloss confirmed a Typhoon had been transiting the area and had now departed on its way," said the Coastguard spokesman.
However, an RAF spokesman at the Ministry of Defence in London said none of their aircraft were in the area at the time and he was at a complete loss to explain how the Coastguard had come by a report to the contrary.
The RAF spokesman said a Nimrod had been flying off the coast but agreed it was not a likely explanation.
Four months ago, callers to BBC Northern Ireland reported strange orange lights in the night sky over Bangor. Air traffic control at Belfast International Airport said it had also received reports, including one from the Coastguard, but there were no records of aircraft in the area.
The Mull of Kintyre is only 25 miles away from the Northern Irish coast and in 2002 the tourist organisation Visit Scotland said Scotland had the highest concentration of UFO sightings of any nation in the world.
In January 1996 the Scotsman newspaper reported concerns that the top-secret USAF aircraft Aurora, which flies at three times the speed of sound, was flying from RAF Machrihanish on the Mull of Kintyre.
In articles spanning several years, the newspaper claimed the stealth spyplane may have been responsible for numerous UFO reports and that its unusual sonic boom was thought to be responsible for earthquakes and avalanches in the Netherlands.
Terry Moseley of the Irish Astronomical Association said that there was an alternative explanation if it was not a plane. It could have been "a fireball exploding up in the atmosphere - perhaps a meteorite or a piece of a comet".
"If that happens above the clouds, you would not see it from the ground," he said.
"That is the most likely explanation if it wasn't a jet."
WJLA-TV Mon, 27 Aug 2007 22:08 EDT
A series of explosions in Northeast have some residents looking for answers, and some law enforcement sources have an idea of what could be to blame.
Debris from used fireworks litters the neighborhood's streets, but residents do not think that is the source of the ear-splitting noise on Friday and Saturday nights along Isherwood street.
"Boom! It was loud; it just sound like something was coming down," said Northeast resident Brittany Slaughter.
Residents say it sounded like a plane crash or an earthquake.
"It could have been a plane, but no plane," said Jewel Thorne. "Wasn't no smoke; it was just the loudest boom I ever could hear."
According to ATF sources, the sounds could be caused by flashbang grenades.
The devices produce a bright flash of light and a loud bang. They are used by law enforcement to distract people during raids.
Some flashbangs recently have been stolen from D.C. police emergency response cruisers in Southeast.
There is no established connection between the missing flashbangs and the noises.
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