From a reasonable source we have an assertion that death by astroid is more likely than death in plane crash. Check this link for a debate involving NASA and JPL
Debate on Astroids for the impatient;
THE ODDS
For U.S. residents, here the odds of dying in certain select ways:
Car Crash: 1-in-100
Electrocution: 1-in-5,000
Asteroid Impact: 1-in-20,000
Plane Crash: 1-in-20,000
Tornado: 1-in-60,000
Bite or Sting: 1-in-100,000
SOURCE:Chapman & Morrison, Nature, 1994
Given these odds why are we preparing for tornados and not asteroids. Is it because the preparation for asteroids is beyond our capacity? If that is the thinking then I propose that we start about community survival rather than individual survival. If we can find a way to bring knowledge, political stability and community values through the mass destruction wrought by asteroid impact then we actually may have survival though we be unable to avoid or mitigate the effects. Just some thoughts.
Hope I haven't strayed too far with this post and I certainly don't mean to be a doom-sayer or wacko! Just looking at the odds and thinking about preparation.