The mean rate of decay of the semi-major axis of the twenty-two (22) USSTRATCOM TLEs from epoch 11349.37540175 to 11354.57578212 (2011 Dec 15 09:01 - Dec 20 13:49 UTC) was 1.3148 km/d. Using the STOAG propagator and actual space weather during that period, I found that the mean rate of decay could be accounted for using A/m = 0.0012813 mē/kg and Cd = 2.2. Using those values with predicted space weather, STOAG propagates the orbit to decay on 2012 Jan 13. Estimated uncertainty is +/- 5 days, based on the rule of thumb of 20 percent of the time remaining to decay. I extracted the actual and predicted space weather data required by STOAG from data provided by Celestrak.com, which compiles data issued by official sources (mainly NOAA) and presents it in a convenient format: http://celestrak.com/SpaceData http://celestrak.com/SpaceData/SpaceWx-format.asp Ted Molczan _______________________________________________ Seesat-l mailing list http://mailman.satobs.org/mailman/listinfo/seesat-l
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