planetarydefense.blogspot.com: January 2006

30 January 2006

Asteroid Impact Mapping System from the Planetary Society

"The specific B612 project that we're hoping to support is aimed at filling part of the gap by creating a system of computerized "automated" maps that will visually depict the specific narrow corridor across the face of the planet within which any given asteroid would strike."

Link

26 January 2006

Christian Science Monitor: Online Poll Results from 2005 on Apophis Mission

Poll results from the last year on a mission to asteroid Apophis.

- Question: "Should NASA launch a mission soon to tag the Apophis asteroid?"

- Result: Yes 78.27%, No 21.73% (out of 925 votes)

Link: Poll results

Link: Original Christian Science Monitor Article

12 January 2006

Rusty Schweickart Responds To Newspaper on NEO Article

“More data on asteroid”
Rutland Herald, Rutland, Vermont
January 11, 2006

With reference to Kendall Wild's Jan. 4 story "Doom from the Sky," I thought it important to correct a couple of understandable but significant errors.

Kendall stated correctly that the NEO "community" of astronomers and others saw a possibility of an asteroid (then 2004MN4, recently named Apophis) hitting Earth in 2029, but then goes on to say that after "some more fine-tuning of their computer data," they decided it wouldn't hit in 2029. This is a common misconception that needs to be corrected and better understood by the public. What changed the astronomers' minds was not fine-tuning existing data (implying that they didn't do a good job the first time) but rather additional (i.e., new) telescopic data. As you get more data the uncertainty in the orbit determination gets smaller and smaller. They didn't make errors. They continued (and still continue) to get more data.

He subsequently states that "in 2029 the asteroid will be closer to the earth than the moon is." True, but far more accurate and impressive is the fact that it will pass less than one-tenth the distance to the Moon — in fact closer to Earth than our communication satellites in geostationary orbit.

Overall, however, it is an excellent article on a subject of far greater importance than most people realize. Unreported (since it was not part of the conference on which Kendall reported) we can prevent impacts by near-Earth asteroids (see the Gravity Tractor, Nature, Nov. 7, 2005), and this capability should be demonstrated before we need to use it. The real question is, will we?

Rusty Schweickart
(Chairman, B612 Foundation)
Tiburon, Calif.

Link

05 January 2006

Radio Show: "Asteroid Apophis due to pass close in 2029"

"Asteroid Apophis due to pass close in 2029"
Program #4,758 of the Earth & Sky Radio Series
Hosts Deborah Byrd and Joel Block
January 13, 2006

"If that object passes through a 600-meter-sized keyhole in 2029, that is, a location in space that is only 600 meters wide, it will indeed hit the Earth in 2036. But the chances of its actually passing through this 600-meter-sized keyhole in space in 2029 are extremely low."

Link (including mp3 link)

Interview with Don Yeomans on NEOs, Mitigation, and Apophis

"...that object [Apophis] is of concern. Not in 2029, when it makes its close approach, but -- once you do have a close approach like that, it makes computing the subsequent orbital position of that object more difficult. So, if that object passes through a 600 meter sized keyhole, in 2029, that is, a location in space that is only 600 meters wide, if it passes through that, it will indeed hit the Earth in 2036. Now the chances of it actually passing through this 600 meter sized keyhole in 2029 is extremely low, and we'll know whether it will or won't probably next year when we get additional radar data in May of 2006. And if we can't rule it our then, there's an additional radar opportunity in 2013 that will almost certainly rule out this possibility. In the unlikely possibility that we don't rule it out in 2013, there's still time to mount a mission to deal with it. This object illustrates the point rather well. It was discovered early, so we have lots of options. The first is to wait until 2013, when this whole thing will almost certainly go away."

Link

Radio Show: "How likely is a killer asteroid?"

Program #4,750 of the Earth & Sky Radio Series
Hosts Deborah Byrd and Joel Block
January 5, 2006

"Although it is classified as potentially hazardous and about 300 meters in size, Apophis doesn't appear to be any threat on its passage in 2029. It's just a great photo opportunity for astronomers."

Link (including mp3 link)

Table of Potentially Hazardous Asteroids (PHAs)

"The following table lists the predicted encounters by Potentially Hazardous Asteroids (PHAs) to within 0.05 AU of the earth from the start of this year through 2178."

Link

Reference to Laser Ablation Mitigation of NEOs

The Journal of the Astronautical Sciences by the American Astronautical Society (AAS).

Park, S.-Y.; and Mazanek, D.D.; "Deflection of Earth-Crossing Asteroids/Comets Using Rendezvous Spacecraft and Laser Ablation," Journal of the Astronautical Sciences, pp. 21-37, Vol. 53, No. 1, Jan-Mar 2005.

The Psychological Reaction to NEOs

"Reacting to Disaster"
By Doug Vakoch
Director of Interstellar Message Composition, SETI Institute

"But if natural human reactions to threats interfere, the ending could be far from uplifting. If fear and denial postpone an adequate response, dust and debris could make the daytime sky look like night, the Earth’s surface could be razed by a global firestorm, and tsunamis could obliterate coastal cities."

"...we need to be aware of our tendency to latch quickly onto one answer, even when subsequent information calls it into question. To guard against such uncritical acceptance of one position, some key decision makers may be selected to play the role of devil’s advocate. By sanctioning the role of dissident, unpopular but potentially vital alternatives can be explored, providing one safeguard against monolithic 'groupthink.'"

Link