Decay watch: April 24/25
Alan Pickup (alan@wingar.demon.co.uk)
Fri, 24 Apr 1998 21:14:08 +0100
The final elset for the Long March rocket was:
Ir 51 CZ-2C r 12.0 3.5 0.0 4.3 d 129 x 110 km
1 25264U 98018C 98114.31817484 .37513683 -14931-5 14791-3 0 1160
2 25264 86.3464 358.1243 0014139 124.9644 235.2815 16.57573902 4674
This shows it surviving long after the time I'd predicted for its decay
(April 24 at ~02:00 UTC). I think decay probably came on this orbit,
possibly around the southbound equator crossing near 159 deg W at 08:22
UTC (April 24.35). Fortunately I have a good set of elsets over the
final day to help with the investigation on how SatEvo went astray.
The latest elset for the Iridium 43 Delta 2 rocket is:
Iridm 43 Delta r 5.9 2.4 0.0 5.6 d 215 x 172 km
1 25044U 97069F 98114.64204652 .04163098 00000-0 83913-3 0 2641
2 25044 83.5240 341.5518 0033120 82.6674 277.9100 16.29631344 26045
This shows it 8 seconds late on the "9257" SatEvo evolution I posted
yesterday. Using a modified SatEvo "Q" factor which gives a better fit
for the Long March decay, I now estimate that this will decay at about
April 25.88. Predicted elsets:
Iridm 43 Delta r 5.9 2.4 0.0 5.6 d 202 x 165 km
1 25044U 97069F 98115.01005260 .05751003 16738-1 84019-3 0 92640
2 25044 83.5227 341.1785 0027970 81.1182 279.1984 16.33303302 26102
Iridm 43 Delta r 5.9 2.4 0.0 5.6 d 184 x 156 km
1 25044U 97069F 98115.37712050 .08722099 43471-1 64791-3 0 92646
2 25044 83.5209 340.8039 0021645 79.5635 280.6803 16.38444707 26160
Iridm 43 Delta r 5.9 2.4 0.0 5.6 d 161 x 142 km
1 25044U 97069F 98115.68190306 .15957075 15298+0 34935-3 0 92647
2 25044 83.5186 340.4901 0014421 78.2618 281.9000 16.45501228 26218
Iridm 43 Delta r 5.9 2.4 0.0 5.6 d 145 x 132 km
1 25044U 97069F 98115.80336135 .26339151 55019+0 27817-3 0 92640
2 25044 83.5167 340.3639 0010203 77.7385 282.3757 16.50391331 26237
Iridm 43 Delta r 5.9 2.4 0.0 5.6 d 133 x 123 km
1 25044U 97069F 98115.86392392 .43414462 18732+1 26631-3 0 92646
2 25044 83.5153 340.3005 0007232 77.4759 282.6049 16.54412872 26245
Alan
--
Alan Pickup | COSPAR site 2707: 55d53m48.7s N 3d11m51.2s W 156m asl
Edinburgh | Home: alan@wingar.demon.co.uk +44 (0)131 477 9144
Scotland | SatEvo satellite page: http://www.wingar.demon.co.uk/satevo/