NASA to Look into NEO Threat Response Proposals

[Snowy Owl]

[FONT=Verdana, Helvetica, sans-serif]NASA to Look into NEO Threat Response Proposals
[FONT=Verdana, Helvetica, sans-serif]By Leonard David
Senior Space Writer
[/FONT][/FONT][FONT=arial,helvetica]posted: 16 May 2006
06:26 am ET

[/FONT] NASA is on the lookout for ways to fend off Earth-threatening Near-Earth Objects. The space agency has issued a call for papers May 15 that, among a range of topics, would help sort out possible alternatives to divert an object if found to be on a likely collision course with Earth.


A U.S. Congress go-ahead on the matter is tied to the NASA Authorization Act of 2005 passed by Congress late last year, and subsequently signed by the President.


"The U.S. Congress has declared that the general welfare and security of the United States require that the unique competence of NASA be directed to detecting, tracking, cataloguing, and characterizing near-Earth asteroids and comets in order to provide warning and mitigation of the potential hazard of such near-Earth objects to the Earth," the Act states.


The Act directs the NASA Administrator to plan, develop, and implement a Near-Earth Object Survey program to detect, track, catalogue, and characterize the physical characteristics of near-Earth objects (NEOs) equal to or greater than 460 feet (140 meters) in diameter in order to assess the threat of such near-Earth objects to the Earth.


Engaging the experts
NASA?s call for papers and selection of best ideas will lead to a NEO Detection, Characterization and Threat Mitigation workshop, to be held in a few months time. This workshop is being organized in support of NASA?s Office of Program Analysis & Evaluation study in response to the congressional direction.
The four-day workshop is to engage experts from the NEO scientific and technical communities to identify the fullest possible set of alternatives for meeting congressional direction. Three focus areas of the workshop are:

• Detection, Tracking and Cataloging NEOs
• Characterization of NEOs, and
• Deflection or other forms of NEO Threat Mitigation

An objective of the workshop is to wrestle with a number of issues, such as what are current U.S. and international capabilities to discover and track NEOs? How does warning time vary with object size for an object on a likely collision course?


Additionally, the workshop would delve into possible need for space-based systems?do they provide advantages over ground-based detection and tracking systems?


Furthermore, can amateur or other astronomers assist with discovery and tracking? How can they be encouraged to do so?perhaps using cash awards for spotting new objects?


Deflection options
In the area of deflection and threat Mitigation of NEOs, the workshop would scope out key options.
For one, what is the ability of a proposed concept to characterize, either remotely or on-the-spot, a NEO for factors related to mitigation, including the size, composition and structure? Also, how best to mitigate the impact effects of a Near-Earth Object found to be on a likely collision course with Earth during a determined time period in the future?
NASA?s call for ideas in abstract submission form is open until May 26. Those selected will be required to submit a full white paper by June 25. The workshop location and dates are yet to be determined, but penciled in for the late June-July time frame.

• Earth-Hitting Asteroids: Katrina From Space
• Deep Impact: Comet Chaser Special Report

<!--%nextpage%--> <!--%offer%--> http://www.space.com/news/060516_nasa_neo.html

 

[DB]

Re: NASA to Look into NEO Threat Response Proposals

http://www.abc.net.au/news/newsitems/200605/s1640173.htm
Comet's tail 'caused Qld light show'
Astronomers are predicting Queenslanders could see more meteorites over the next few days, if last night's spectacular light show was the result of a comet that passed by the Earth over the weekend.
A bright green ball of light was seen in many parts of Queensland about 6:30pm AEST.
Andre Claydon, from the Springbrook Observatory, says the comet is the most likely explanation for the rare phenomenon.
"There is a comet that has just gone past and we're passing through the debris tail of this comet," he said.
"This could be a fragment from the comet itself.
"Over the next two or three days we should see more of this happening, because the Earth is stilling passing through the debris tail of this comet."
But a South Burnett astronomer says the spectacle was probably the result of space junk entering the earth's atmosphere.
Jim Barclay, from the Maidenwell Observatory, says the light could not have been caused by a meteorite.
"Most meteors do not, and I repeat, do not appear of the green-blue fluorescent colours that these people described," he said.
"Metallic substances tend to burn up and give you that greeny-blue fluorescent colours where meteors are generally white in nature."
Green light

Paul, from Coolum on the Sunshine Coast, says he was driving away from Brisbane when he saw the giant ball of green light.
"One bloke just said, 'Wow, look at that' and it was just right across the sky," he said.
"It was massive and it was green.
"At the main body of it, there were actually parts of it falling down to the ground."
Steve, from the bayside suburb of Birkdale, was travelling in a plane over Casino at 11,000 when he saw it break up in front of him.
"It was just amazing," he said.
"It just looked like it was just in front of us.
"It was very white from up there - just sort of went out in front of us and we saw ... red bits falling and then it just went out."

 

[Bruce]

Re: NASA to Look into NEO Threat Response Proposals

I thought all comets were acounted for.

 

[DB]

Re: NASA to Look into NEO Threat Response Proposals

Bruce,

Nope.

http://www.baltimoresun.com/news/health/bal-hs.comet05may05,0,7176805.story?coll=bal-health-headlines

"It's driving us nuts; fragments of fragments of fragments," said Don Yeomans, manager of NASA's Near Earth Objects Program office at the Jet Propulsion Laboratory in Pasadena, Calif. It is his job to keep track of them all and tell astronomers where to find them.

"It's doing its best to make our lives miserable," he said, laughing.


There are literally thousands of fragments.

 

[Laidback Al]

Re: NASA to Look into NEO Threat Response Proposals

Bruce, Near earth objects (NEO) include asteroids as wells as comets. Comets, because of their composition as "dirty snowballs" emit gases that are readily visible from earth through telescopes, binoculars, etc. Asteroids on the other hand are usually made up of dark stoney, non-reflective materials. They are hard to see through telescopes, especially if they are very small. Small is a relative term in regards to these near earth objects. General scientific consensus is that a meteor exploded in the atmosphere in 1908 in Russia producing an explosion equal to 10-15 megatons of TNT, the Tunguska Event. (http://en.wikipedia.org/wiki/Tunguska_event)

That meteor was estimate to be only 10 m in diameter. I am not sure what the size resolution is for NASA to be tracking small near earth objects, it obviously depends on the size and trajectory in relation to both the earth and the sun (for reflection). I seem to remember reading somewhere that NASA estimates that it is currently tracking less than half of all NEO that could have significant effect on earth if an impact occurred.

And as if we don't have enough to worry about already with the H5N1 situation in Indonesia.


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[DB]

Re: NASA to Look into NEO Threat Response Proposals

http://www.jpl.nasa.gov/news/news.cfm?release=2006-075

"...The comet dust also adds up to more evidence for the "icy dirtball" theory of comets. In recent years, more and more astronomers are coming to think of comets not as snowballs coated in dust, but as dirtballs crusted with ice..."

It seems the "dirty snowball" idea is going the way of the dinosaur.

 

[DB]

Re: NASA to Look into NEO Threat Response Proposals

http://www.northernstar.com.au/localnews/storydisplay.cfm?storyid=3684873&thesection=localnews&thesubsection=&thesecondsubsection=
Comet debris turns on a spectacular display in night sky

18.05.2006
By WILL JACKSON
EVER wanted to know what a fridge hurtling through the atmosphere at 57,000km/h looks like?

Well, even if you haven?t, watch the skies tonight and you might be able to see.

The huge fireball that swooped across the sky about 6.20pm on Tuesday was actually a refrigerator sized hunk of comet, astronomer Andre Claydon said yesterday.

The Earth is passing through debris left by Comet 73P/Schwassmann-Wachmann which has broken up into about 64 pieces, said the director of observation at the Springbrook Observatory near the Gold Coast.

Some of these pieces were hitting the atmosphere and would continue to create a spectacular light show for another five days.

However, they were unlikely to be quite as incredible as Tuesday night?s meteor, which caused quite a stir across the region.
A police spokeswoman said it was seen travelling west as far inland as Warwick in Queensland.

She said a Warwick farmer alerted police about 6.30pm of what he thought was a fireball from a plane crashing on his property.

However a search of the area found nothing.

Police were then inundated by sightings of a ?green ball of light?.

Andre said the meteor shower would have appeared much closer than it actually was.

"As it comes in through our atmosphere we get a magnification effect, so it always looks a lot closer, but it is probably 60 to 70km inside our atmosphere," he said.

"I had a number of phone calls specifically from the eastern part of Australia regarding a meteor shower that has come through and broken up into a few pieces."

 

[Bruce]

Re: NASA to Look into NEO Threat Response Proposals

Thanks both, and WOW.