Re: [find_orb] Re: Chelyabinsk Meteorite

Bill Gray May 24, 2013

Hi Andy,

> and I know the story was still developing during that time.
> Did you actually see the change in apparent motion soon
> enough that it clued you in to what was happening in real time?

No. At the time, all we had were the (854) and (G96)
data, a 2.4 hour arc, which didn't look particularly
unusual. But the NEOCP ephemerides default to showing the
next 24 hours. At the time I looked, those ephems showed
gradually increasing motion for seventeen hours, and then
a sudden "zing". I didn't save the NEOCP ephems, but I can
recreate what I saw at the time :

http://www.projectpluto.com/temp/mpec.htm

Take a look at the '/hr column, and you'll see what I mean.
That, and the object getting seven magnitudes brighter,
caused me to spit coffee onto my keyboard.

-- Bill