Sciencescienceapophisasteroid20292036

Fri Oct 16, 2015, 10:53 AM

Something for your "to do" list in 2029. And if very unlucky, 2036...

To those who follow space news, 2004 MN4 is hard to forget. Around last Christmas, astronomers ranked this asteroid's (Apophis) chances of striking Earth April 13, 2029, at 1 in 37, giving it an unprecedented threat level of 4 on the Torino impact-risk scale. By the end of January, additional observations reduced the risk to 1 in 10,000, ruling out a 2029 impact — but not a future strike.

The new orbit held a surprise. It moved the location of MN4's close 2029 pass outside the error box, the volume of space containing the probable positions computed by previous determinations. This isn't supposed to happen. Clark Chapman, a prominent Near-Earth object (NEO) researcher at the Southwest Research Institute in Boulder, Colorado, found this occurrence so disturbing he suggested that alternate mathematical approaches might be better suited to characterize NEO impact risks than what astronomers are currently doing. Such techniques are used to evaluate risks of airline accidents or nuclear power plant disasters. 

If 2004 MN4 passes through the keyhole, Earth's gravity could deflect it just enough for an impact in April 2036. The keyhole's existence is why the impact risk hasn't dropped to zero. Optical and even radar observations aren't sufficient to nail down the asteroid's location to within 600 yards — only about 1.7 times the asteroid's diameter. Achieving "adequate accuracy" is why Rusty Schweickart is urging we intercept MN4 and place a transponder and some scientific instruments on its surface, before 2014. Why so early? Astronomers need time to collect the precision data that will determine whether MN4 will pass through the keyhole. 

http://www.astronomy.com/news/2005/05/the-asteroid-and-the-keyhole

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Reply Something for your "to do" list in 2029. And if very unlucky, 2036... (Original post)
Gamle-ged Oct 2015 OP
Currentsitguy Oct 2015 #1
Noumenon Oct 2015 #2
misanthroptimist Oct 2015 #3

Response to Gamle-ged (Original post)

Fri Oct 16, 2015, 11:00 AM

1. Familiar with it

I plan on throwing one hell of an End of the World party that day. You know, booze and loose women and debauchery, etc...

Just kidding. NEO work needs far more attention than it currently receives. I know the French are planning an impactor for Apophis to study it's composition. I'm not so sure it's such a good idea to potentially alter the trajectory of a object passing so close to us.

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Response to Gamle-ged (Original post)

Fri Oct 16, 2015, 10:33 PM

3. Stick a solar sail on it and let Mars worry about it.

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Sciencescienceapophisasteroid20292036