Decay watch: May 15 (Final orbits of Iridium 70 Delta 2)
Alan Pickup (alan@wingar.demon.co.uk)
Sat, 15 May 1999 11:49:52 +0100
Apparent connectivity problems between my ISP and OIG's server are
preventing me from updating the SpaceCom prediction for the decay of
the Iridium 70 Delta 2 rocket. However, I have obtained updated elsets
via another route...
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Object: #25347 = 98- 32 F = Iridium 70 Delta 2 r
Decay predictions:
Source Prediction made Predicted decay at Latitude Longitude
UTC UTC deg deg
SpaceCom May 11 17:34 May 15 18:01 +-2d 18.5 S 124.9 E
SpaceCom May 12 19:49 May 15 18:13 +-2d 60.8 S 163.8 E
SpaceCom May 13 13:36 May 15 13:25 +-9h 19.8 S 69.2 E
SpaceCom May 14 15:01 May 15 15:25 +-15h 26.7 S 146.2 W
SatEvo May 9 14:25 May 15 18:00 +-1.5d
SatEvo May 12 18:20 May 15 17:42 +-15h
SatEvo May 13 19:20 May 15 11:41 +-9h 30.0 N 88.7 E
SatEvo May 14 18:50 May 15 11:49 +-5h 0.0 90.1 E
SatEvo May 15 10:30 May 15 14:05 +-2h 16.1 N 122.4 W
Latest elset:
Iridm 70 Delta r 5.9 2.4 0.0 5.6 d 168 x 160 km
1 25347U 98032F 99135.28000050 .09277033 -16217-5 69828-3 0 4721
2 25347 84.0964 320.2747 0006391 26.5718 333.6003 16.40642020 56236
SatEvo prediction:
Iridm 70 Delta r 5.9 2.4 0.0 5.6 d 159 x 152 km
1 25347U 98032F 99135.40185343 .15761747 23824+0 59605-3 0 94727
2 25347 84.0953 320.1602 0005323 26.0449 333.9818 16.43846996 56253
Iridm 70 Delta r 5.9 2.4 0.0 5.6 d 153 x 147 km
1 25347U 98032F 99135.46269100 .22071940 52866+0 53532-3 0 94725
2 25347 84.0946 320.1029 0004595 25.7809 334.2420 16.46097201 56268
Iridm 70 Delta r 5.9 2.4 0.0 5.6 d 143 x 138 km
1 25347U 98032F 99135.52342568 .39741758 18594+1 51918-3 0 94728
2 25347 84.0935 320.0454 0003538 25.5162 334.5012 16.49630146 56278
Note: The current elset has it 31 seconds late on yesterday's
prediction, suggesting that SpaceCom's (and Harro's) later decay times
have been nearer the mark. I now calculate decay following a northbound
equator crossing over the W Pacific on a track that would reach San
Francisco at 14:10 UTC. It could still survive for another orbit.
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Alan
--
Alan Pickup | COSPAR 2707: 55d53m48.7s N 3d11m51.2s W 156m asl
Edinburgh | Home: alan@wingar.demon.co.uk +44 (0)131 477 9144
Scotland | SatEvo page: http://www.wingar.demon.co.uk/satevo/