RE: Unidentified satellite - need help with identification

From: Ted Molczan (
Date: Mon Mar 23 2009 - 19:55:21 UTC

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    T.J. responded:
    > > ... how long did it take to traverse from 2 degrees east of
    > > Alnitak to the point of fadeout in the N.E.? We can attempt to
    > > reconcile that with the expected motion of an object orbiting
    > > sufficiently high to have been clear of the shadow.
    > I would estimate that it took maybe 45 seconds to a minute to 
    > traverse that portion of the orbit.
    For an object in a circular orbit to have traversed from ~2 degrees east of
    Alnitak to 45 deg above the NNE horizon, in one minute, it must have been at an
    altitude of about 185 km, which would have placed it within Earth's shadow, and
    invisible. A re-entering object would have been lower than 100 km, and would
    have glowed, but Space Track does not list any decays on Mar 19 UTC. That pretty
    much rules out an orbiting object.
    Ted Molczan
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