Peter Wakelin observed USA 200 during 6.4 hours last night: http://satobs.org/seesat/Apr-2008/0048.html Adding his new observations to those he made on Apr 05 UTC, yields the following elements: 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 ------------------------------------------------------------------------- Subscribe/Unsubscribe info, Frequently Asked Questions, SeeSat-L archive: http://www.satobs.org/seesat/seesatindex.html
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