Rainer posted: >I have found a solution for the Apr 04/05 >observations with a negative ndot. >This elset suggests that 88-99A has manoeuvred. I agree this elset is a "solution" to these observations and this enormous negative ndot term indicates a maneuver. Of course such a maneuver would likely change the eccentricity, inclination, and argument of perigee to a small extent. Last year when the mean motion changed from 14.85 to 14.75, the eccentricity changed from 0.049 to 0.0533, the inclination decreased by 0.04 degrees and the argument of perigee changed by 5 degrees or so. I have determined that the following two elsets come fairly close to satisfying the observations while keeping the RA of ascending node with a consistent value: 1 19625U 88 99 A 96 95.82605758 0.00010000 00000-0 10779-3 0 08 2 19625 97.8000 158.8000 0490000 2.2245 357.7753 14.85000000 04 1 19625U 88 99 A 96 96.84017058 0.00010000 00000-0 11674-3 0 06 2 19625 97.8600 159.8045 0530000 356.6120 3.3879 14.75000000 05 Of course the mean motions given here are simply a guess and could be in error by more than 0.01 revolutions/day. But I hope the second elset may provide guidance for the search. Mike McCants mike@comshare.com