NEO News (06/18/09) Summer Stories

From Dave Morrison.

NEO News (06/18/09) Summer Stories

This edition of NEO news is devoted to several current stories that are creating some press and public interest. Some are serious, others are just summer madness. In any case, it is perhaps useful that we be aware of these issues.

David Morrison

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SURVEILLANCE SATELLITE DATA ON BRIGHT FIREBALLS
As first discussed a week ago in an article by Leonard David on Space.com, there is a move to stop releasing the routine observations of large fireballs that have been made by U.S. surveillance satellites. Peter Brown at University of Western Ontario and others have made good use of these data to define the impact frequency for objects in the meter size range and to help locate meteorite falls such as Tagish Lake. This is a serious issue, although some news sources are greatly exaggerating by claiming that the absence of global fireball data somehow increases public risk from impacts. Unfortunately, this topic feeds those who are already paranoid about government secrecy. Following is a sober summary of the issues from Nature on-line:

ASTRONOMERS LOSE ACCESS TO MILITARY DATA
Satellite information on incoming meteors is blocked.
Geoff Brumfiel, Nature, 12 June 2009

The US military has abruptly ended an informal arrangement that allowed scientists access to data on incoming meteors from classified surveillance satellites. The change is a blow to the astronomers and planetary scientists who used the information to track space rocks, especially those that burn up over the oceans or in other remote locations. "These systems are extremely useful," says Peter Brown, an astronomer at the University of Western Ontario in London, Canada. "I think the scientific community benefited enormously."

When the policy changed is unclear. The website Space.com reported the end of the relationship on 10 June, but Brown says that he was told at the beginning of this year that there would be no further data releases. Mark Boslough, a physicist at Sandia National Laboratories in Albuquerque, New Mexico, says he was told this spring that he could no longer publicly discuss the classified data to which he had some access. Neither scientist could give a reason for the end of the arrangement, and the United States Air Force, which operates the satellites, did not respond in time for Nature's deadline. The Air Force did issue a 16 March memo on the military classification of fireball data, but Nature could not confirm its contents.

The Defense Support Program satellite network is part of the Pentagon's early-warning system. Since 1970, 23 infrared satellites in the series have been launched into geosynchronous orbit to monitor the globe for missile launches or atmospheric nuclear blasts.

But the same infrared sensors were perfect for spotting fireballs as they streaked across the atmosphere, according to Brian Weeden, a former Air Force captain who now works at the Secure World Foundation, a non-profit organization based in Superior, Colorado. The satellites could precisely detect the time, position, altitude and brightness of meteors as they entered Earth's atmosphere. Weeden, who left the Air Force in 2007, says that the military didn't consider that information particularly useful, or classified. "It was being dropped on the floor," he says.

Under an informal arrangement, at least some of the data seem to have been provided on an ad-hoc basis to scientists studying meteorites. Often it came in the form of an anonymous, tersely worded e-mail describing the coordinates, altitude and size of a fireball. Brown, who has collected the data since 1994, declined to specify who sent the reports.

Even the short descriptions of events were enormously helpful. In 2002, Brown and his colleagues used a larger data set from the satellites to quantify the number of objects striking Earth each year (P. Brown et al. Nature 420, 294-296; 2002). Last year, they were used to narrow the search for remnants of the asteroid 2008 TC3 in the Sahara Desert in North Africa, and they were also crucial in recovering a meteorite fragment in 2000 from Tagish Lake in northern Canada. "In both of those cases it's hard to say whether this would have been picked up without the satellite data," Boslough says.

The data also provide a useful check against ground-based instruments monitoring low-frequency sound waves and dust from the fireball explosions, says Brown.

Brown says that whatever the reason, the end of the relationship has left the tight-knit meteorite community smarting. The global reach of the satellites and the data they supplied were unparalleled, he says. "There's nothing else that even comes close," he says.

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GERMAN BOY (NOT) HIT BY METEORITE

There has been considerable Internet chatter about a claim that a 14-year-old boy in Essen, Germany, was knocked off his bicycle by a small meteorite. There were no other witnesses, but his story was apparently believed at least locally in Germany, and it has spread widely. The "facts" as reported are almost entirely wrong. However, we do not know what actually happened, or whether the implausible accounts come from the boy or local reporters. Much of the following information is from the Discover-Badastronomy website of Phil Plait (blogs.discovermagazine.com/badastronomy/2009/06/12/a-boy-claims-he-was-hit-by-a-meteorite/).

The original English-language story is from the Telegraph in UK (www.telegraph.co.uk/scienceandtechnology/science/space/5511619/14-year-old-hit-by-30000-mph-space-meteorite.html). They wrote:

Gerrit Blank, 14, was on his way to school when he saw "ball of light" heading straight towards him from the sky. A red hot, pea-sized piece of rock then hit his hand before bouncing off and causing a foot wide crater in the ground. The teenager survived the strike, the chances of which are just 1 in a million - but with a nasty three-inch long scar on his hand.

He said: "At first I just saw a large ball of light, and then I suddenly felt a pain in my hand. Then a split second after that there was an enormous bang like a crash of thunder. The noise that came after the flash of light was so loud that my ears were ringing for hours afterwards. When it hit me it knocked me flying and then was still going fast enough to bury itself into the road," he explained.

Scientists are now studying the pea-sized meteorite which crashed to Earth in Essen, Germany. Chemical tests on the rock have proved it had fallen from space. Ansgar Kortem, director of Germany's Walter Hohmann Observatory, said: "It's a real meteorite, therefore it is very valuable to collectors and scientists."
What are we to make of this? Most of the "facts" don't bear close examination. The "meteorite" is pea sized and looks like a small piece of gravel. If it is a meteorite, it must have been the product of the explosion/disintegration of a larger meteor many kilometers high (since small meteorites can't make it through the atmosphere). It would have reached the ground at terminal velocity (which is low for a pea-size rock) several minutes after the high-altitude explosion. Such a small stone could not make a crater or do any damage to a paved street. It would also have been cool (it would quickly equilibrate with the air it was falling through). Compare this with the story reported in the newspapers:

Speed 30,000 mph - impossible (unless they mean the entry speed)
Red-hot - impossible
Brilliant fireball coming straight toward the boy - impossible
Loud sound at time it hit - impossible
Burned hand - not from the meteorite
Crater in road - not supported by photos

The question of whether this was a real meteorite apparently is also open. A writer to the badastronomy blog wrote: "I just checked the German sites reporting this. Ansgar Korte is quoted as saying “Ist es tatsächlich ein echter Meteorit, dann hat das Exemplar sogar einen gewissen Wert für Sammler und Mineralogen." That would correctly be translated to "IF it is a real meteorite, it would have a certain value for collectors and mineralogists." In any case, a pea-sized meteorite is easily purchased (and inexpensive) if someone wanted to fabricate a hoax.
I have no clue where the fault is, but I recommend skepticism in accepting this story as evidence of a person being hit directly by a meteorite.

David Morrison

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ARECIBO SUPPORT

Rusty Schweickart reports the following note from the AAAS public policy blog, quoting from the recent U.S. House Appropriations bill providing FY10 funding for NASA:

Near Earth object observations -- The recommendation includes $5,800,000 for near Earth object observations, an increase of $2,000,000 to support ongoing scientific research at the Arecibo Observatory in the fields of climate change and space weather...

The fact that this item is listed under NEOs suggests that the members of Congress may intend this as operating support for the Arecibo planetary radar, which has been so valuable in studying both the orbits and the physical characteristics of NEOs. However, the underlying issue of the continued operations of the entire Arecibo Observatory, which is managed and funded by the National Science Foundation, does not seem to be addressed in this section of the Appropriations bill.

Stay tuned Š.

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SUMMER DISASTER MOVIE "IMPACT"

An ABC-TV mini-series called "Impact" will be broadcast in the U.S. on June 21. You will find the trailer and some comments on the Badastronomy website at (blogs.discovermagazine.com/badastronomy/2009/06/15/if-i-watch-this-i-hope-the-moon-will-hit-the-earth/).

The movie plot seems to be that a giant meteor storm hits the Moon, excavating huge rocks (bigger than mountains) that rain down on Earth. Then comes the bad part. The meteors contained a "piece of a brown dwarf" which is embedded in the Moon and has increased its mass to twice the mass of the Earth (perhaps they were thinking of a white dwarf, which is extremely dense, not a brown dwarf). Apparently this produced an increase in gravitational mass but not inertial mass (another miracle of nature) because the Moon is now headed for a collision with the Earth. If you care about the outcome, you will need to watch the film.

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FALL DISASTER MOVIE "2012"
Stories about the fictional planet Nibiru and its collision with Earth in December 2012 have blossomed on the Internet. Claims about a 2012 doomsday are the theme of a new from Columbia Pictures titled "2012", to be released in November 2009. Apparently cosmic impacts are a part of the plot.

The film's trailer, appearing in theaters and on their website, shows a tidal wave breaking over the Himalayas, with only the following words: "How would the governments of our planet prepare 6 billion people for the end of the world? [long pause] They wouldn't. [long pause] Find out the Truth. Google search 2012".

The film publicity includes creation of a faux scientific website (www.instituteforhumancontinuity.org/) for "The Institute for Human Continuity", which is entirely fictitious. According to this website, the IHC is dedicated to scientific research and public preparedness. Its mission is the survival of mankind. The website explains that the Institute was founded 1978, and in 2004 IHC scientists confirmed with 94% certainty that the world would be destroyed in 2012. This website encourages people to register for a lottery to select those who will be saved. I learned from Wikipedia that this sort of fake website is a new advertising technique called "Viral Marketing", by analogy with computer viruses.
For lots more information on the Nibiru and 2012 hoaxes see (astrobiology.nasa.gov/ask-an-astrobiologist/intro/nibiru-and-doomsday-2012-questions-and-answers). For the film, we will have to wait until late November.

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NEO News (now in its fourteenth year of distribution) is an informal compilation of news and opinion dealing with Near Earth Objects (NEOs) and their impacts. These opinions are the responsibility of the individual authors and do not represent the positions of NASA, Ames Research Center, the International Astronomical Union, or any other organization. To subscribe (or unsubscribe) contact dmorrison@arc.nasa.gov. For additional information, please see the website http://impact.arc.nasa.gov. If anyone wishes to copy or redistribute original material from these notes, fully or in part, please include this disclaimer.