Meteors

Does it bother anyone else, as it bothers me, that there are so many unanswered questions about the meteor that caused havoc in Russia recently?  As I write this, another meteor, 2012DA14, is making its closest path to the earth, some 17,000 miles, and is not expected to have noticeable physical impact nor will it be visible to the naked eye.

Scientists have tracked 2012DA14 for months, but the as yet-unnamed meteor in Russia seems to have come as a surprise.  Why?  An explanation given on NBC this morning is that the one in Russia was much smaller.  Wait!  The one in Russia was said to be 15 meters in diameter; 2012DA14 was reported to be one-third the size of a football field (30 meters in diameter).  If those estimates are correct, is that enough difference enough to account for the difference of effects?  I don’t think so; we must ask how close the one in Russia came to the earth to have exploded and burned up in the atmosphere.

Knowing how close the Russian meteor came to the earth, scientists can determine where it should have been detected on radar or by other means.   Radar return signals attenuate with the 4^th power of the distance (conversely increase with the 4^th root of the distance for an approaching object).   So somewhere as it approached closer to the earth, the Russian meteor should have produced a stronger radar return than 2012DA14. 

I suspect that there are scientists frantically scratching their heads or punching their computers looking for an explanation.  Perhaps the answer is already known and it has not gotten to the media.  I hope that it hasn’t been blocked for political reasons.  But whatever, the media needs to probe more deeply into this question.