Updated elements of USA 200 and 08591A

From: Ted Molczan (ssl3molcz@rogers.com)
Date: Tue Apr 08 2008 - 15:39:31 UTC

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    Peter Wakelin observed USA 200 during 6.4 hours last night:
    Adding his new observations to those he made on Apr 05 UTC, yields the following
    USA 200          0.0  0.0  0.0  3.7 v                 1184 X 39159 km
    1 32706U 08010A   08098.66566390  .00000000  00000-0  00000-0 0    06
    2 32706  63.8288  41.1541 7151785 270.6660  15.5171  2.00672998    05
    Arc 2008 Apr 05.83 - 08.11, WRMS residuals = 0.007 deg
    The mean motion is now close to the ~2.006 rev/d operational value of a standard
    Molniya orbit, so the major post-launch manoeuvres have been completed. This is
    confirmed by Peter's observation that its brightness is now steady. Experience
    tracking sister spacecraft USA 184, revealed the presence of a ~5 rpm rotation
    during the major post-launch manoeuvres, which ceased soon after reaching the
    planned orbit.
    Peter also made new observations of the UNID he initially observed on Mar 31,
    yielding the following orbit:
                                                           459 X 13810 km
    1 90080U 08591A   08098.95368218  .00000000  00000-0  00000-0 0    00
    2 90080  63.3628 178.4152 4940458 292.2329  23.5439  5.52648554    08
    Arc 2008 Mar 31.02 - Apr 08.00, WRMS residuals = 0.005 deg
    In accordance with our convention for unidentified orbiting objects, I have
    assigned our next available UNID catalogue number, 90080, and the pseudo
    international designation 08591A. The first two digits of the latter denote the
    year of the initial observation. The next three digits minus 500, denote the day
    of the year of the initial observation. The letter distinguishes among multiple
    unidentified objects that may be initially observed on the same day. 
    Peter reports that the object is bright, so it may be visible in binoculars when
    near perigee. Analysis of its brightness will assist in identifying this object,
    which most likely is related to a past U.S. launch to Molniya orbit.
    Numerical integration using int2 and int3 indicates that the object will remain
    in orbit for at least several decades. Its eccentricity will decrease during the
    next ~7 years, raising the apogee to more than 700 km, after which eccentricity
    will again increase, with perigee likely to drop below 300 km within a few years
    of 2030.
    Ted Molczan
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