Is this topic appropriate for this group? Maybe so if you read my last
paragraph.
An Australian friend of mine asked me:
"I was amazed that there was no heads-up on the
meteorite that struck in Russia recently.
Is NORAD not able to track these?"
I found these articles using Google. My friend could have found them too.
http://ogleearth.com/2013/02/reconstructing-the-chelyabinsk-meteors-path-wit
h-google-earth-youtube-and-high-school-math/
http://www.technologyreview.com/view/511691/astronomers-calculate-orbit-of-c
helyabinsk-meteorite/
And this paper.
http://arxiv.org/abs/1302.5377
As I understand it, the authors of that paper used NOVAS to calculate the
orbit.
Couldn't they just as well have used Find_Orb?
How did this meteorite sneak up on us without having been observed while
inbound?
With a direct orbit, I think it should have been observable after sunset
while
it was inbound. Has anybody calculated its proper motion relative to its
radiant
position in the sky? Was it too small for the motion to be noticed?
Would I be wasting my time if I used Find_Orb to study this question? I
would
attempt to compute the proper motion of this body as a function of time over
many days while it was inbound to start with. Then I would use Guide to plot
the incoming radiant in the field of stars to see if there is any bright
star nearby
that would hide this object in its glare. If so, that might be considered
to be an
observation over several days at the same position. Then I might look at how
sensitive the displacement from that radiant was to variations in each of
the
heliocentric orbital elements. Does any of that sound feasible to you?
-Glen