RE: Fobos-Grunt: new pieces catalogued by USSTRATCOM

From: Ted Molczan (
Date: Sat Dec 03 2011 - 16:43:35 UTC

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    I have determined that object 11065H / 37947 separated and from Fobos-Grunt on Nov 29, roughly mid-day UTC. I have not
    estimated the velocity of separation, but it appears to have been fairly gradual, more likely something that came loose
    and drifted away, than exploded away. 
    Using STOAG, I estimate that it's A/m was about 0.022 m^2/kg, assuming Cd=2.2, and using actual space weather. It
    decayed from orbit on Dec 01 UTC.
    Here is the plot of evolution of mean altitude:
    Although much less dense than its parent body, the object was fairly dense. Its areal density (m/A) was about 45 kg/m^2.
    USSTRATCOM has published its RCS value (radar-cross section area), which indicates it was fairly small in size. Very
    roughly, it could have been about 10 cm across. Applying the A/m, its mass was roughly 0.5 kg.
    Before anyone invests too much effort into trying to guess the identity of the object, it would be useful to have the
    results of at least a couple other independent estimates of A/m.
    Ted Molczan
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