Decay watch: April 23/24
Alan Pickup (alan@wingar.demon.co.uk)
Thu, 23 Apr 1998 23:24:30 +0100
The most recent elset for the Iridium 51 Long March rocket is:
Ir 51 CZ-2C r 12.0 3.5 0.0 4.3 d 212 x 136 km
1 25264U 98018C 98113.71000865 .08454168 -12303-5 23899-3 0 1070
2 25264 86.3625 358.4912 0057908 57.4334 303.3457 16.36928954 4572
This shows it 3.2 sec early against the "9095" SatEvo evoltion I posted
yesterday.
I now predict decay for about April 24.08 (~02:00 UTC +-2h).
Predicted elsets:
Ir 51 CZ-2C r 12.0 3.5 0.0 4.3 d 187 x 132 km
1 25264U 98018C 98113.89305421 .17612395 20621+0 32950-3 0 91075
2 25264 86.3608 358.3855 0042312 56.6176 303.7864 16.42322584 4600
Ir 51 CZ-2C r 12.0 3.5 0.0 4.3 d 177 x 130 km
1 25264U 98018C 98113.95393578 .22805122 39553+0 34779-3 0 91075
2 25264 86.3600 358.3502 0035643 56.3447 303.9946 16.44747818 4615
Ir 51 CZ-2C r 12.0 3.5 0.0 4.3 d 162 x 127 km
1 25264U 98018C 98114.01471039 .34114854 99284+0 37994-3 0 91079
2 25264 86.3589 358.3147 0027411 56.0713 304.1889 16.48099807 4625
Ir 51 CZ-2C r 12.0 3.5 0.0 4.3 d 138 x 118 km
1 25264U 98018C 98114.07531669 .84684564 76845+1 49508-3 0 91079
2 25264 86.3571 358.2791 0015252 55.7969 304.3475 16.54243731 4637
The final rev takes it northbound across the equator at 119 deg E at
01:48 UTC at southbound across the equator at 72 deg W at 02:32 UTC.
That southbound ground-track passes between Quebec and Montreal at
02:21 UTC and between New York and Boston a minute or so later.
The latest elset for the other decaying Iridium rocket ...
Iridm 43 Delta r 5.9 2.4 0.0 5.6 d 238 x 183 km
1 25044U 97069F 98113.71896087 .02337494 -13891-5 78195-3 0 2574
2 25044 83.5247 342.4817 0041786 82.7688 277.8396 16.23277329 25898
... shows it 14 seconds late on yesterday's prediction.
My new evolution indicates decay at April 25.7 +-0.4d.
Prediction:
Iridm 43 Delta r 5.9 2.4 0.0 5.6 d 231 x 180 km
1 25044U 97069F 98114.02698221 .03079270 48726-2 89896-3 0 92575
2 25044 83.5241 342.1725 0038427 81.4853 278.9501 16.25171359 25949
Iridm 43 Delta r 5.9 2.4 0.0 5.6 d 218 x 175 km
1 25044U 97069F 98114.51907705 .04072999 93640-2 91228-3 0 92578
2 25044 83.5228 341.6767 0032346 79.4272 280.9370 16.28638800 26029
Iridm 43 Delta r 5.9 2.4 0.0 5.6 d 199 x 167 km
1 25044U 97069F 98115.00993506 .06307365 25190-1 92529-3 0 92576
2 25044 83.5211 341.1791 0024838 77.3624 282.9152 16.33555248 26107
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/