Cees Bassa, Simone Corbellini, Bram Dorreman, Russell Eberst, Marco Langbroek, Jon Mikel, Pierre Neirinck, Alberto Rango and Mike Waterman, reported observations used to update the elements of USA 245: USA 245 259 X 1007 km 1 39232U 13043A 13246.88583386 .00023602 00000-0 22684-3 0 06 2 39232 97.8718 310.2685 0533236 173.6946 187.1349 14.77795461 08 Arc 20130901.8-0903.9 WRMS resid 0.018 totl 0.011 xtrk As Marco mentioned, the object was early and off-track relative my previous TLE. The early arrival probably was due an increase in rate of decay. The off-track is due to an error in the elements mostly affecting the eccentricity of the orbit. Depending on which points I included, the analysis yielded vales between about 0.0525 and 0.0534. All solutions revealed closest approach to the pre-manoeuvre orbit on Saturday, August 31, near the apogee passage of 18:30:39 UTC. The 0.0525 eccentricity solution seemed more correct, because it closely matched the altitude of the pre-manoeuvre orbit (manoeuvres can only occur at the intersection between the existing and intended orbit). The 0.0534 solution was not a good match in altitude, at apogee or anywhere else around the orbit. Nevertheless, it appears that 0.0533 eccentricity is close to correct. Perhaps two small manoeuvres were made at locations other than perigee or apogee, that happened to yield closest approach to the pre-manoeuvre at the aforementioned apogee. Ted Molczan _______________________________________________ Seesat-l mailing list http://mailman.satobs.org/mailman/listinfo/seesat-l
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