Decay watch: Jun 5

Alan Pickup (alan@wingar.demon.co.uk)
Sat, 5 Jun 1999 15:32:32 +0100

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Object: #25728 = 99- 24 B = Orion 3 Delta 3 r

Decay predictions:
Source   Prediction made    Predicted decay at      Latitude Longitude
               UTC                UTC                  deg      deg

SpaceCom   Jun  1 22:01     Jun  5 22:06 +-3d         7.2 S   173.4 E
SpaceCom   Jun  2 17:20     Jun  5 16:10 +-2d        17.2 S    75.2 E
SpaceCom   Jun  3 17:42     Jun  5 17:43 +-10h       21.2 S    89.0 W
SpaceCom   Jun  4 18:37     Jun  5 19:05 +-17h        7.1 S   140.4 W
SpaceCom   Jun  5 09:41     Jun  5 20:48 +-7h        20.0 S   109.7 W

SatEvo     Jun  1 19:30     Jun  6 05:00 +-1.5d
SatEvo     Jun  2 19:15     Jun  5 23:00 +-1d
SatEvo     Jun  3 19:30     Jun  5 23:13 +-12h
SatEvo     Jun  4 21:45     Jun  6 23:13 +-8h
SatEvo     Jun  5 14:00     Jun  6 23:10 +-4h        22.1 N    97.4 E

Latest elset (34 sec early on yesterday's prediction):
Ori 3 Delta 3 r                                  347 x 134 km
1 25728U 99024B   99156.26857625  .14080445 -62401-5  62166-3 0  1013
2 25728  29.4658 209.6854 0161073 123.0525 238.5684 16.12273955  4641

SatEvo prediction:
Ori 3 Delta 3 r                                  278 x 129 km
1 25728U 99024B   99156.63837863  .23327555  14189+0  62148-3 0 91014
2 25728  29.4632 206.8388 0112786 127.6139 233.4154 16.25894187  4705
Ori 3 Delta 3 r                                  246 x 127 km
1 25728U 99024B   99156.76085446  .30582611  28950+0  61008-3 0 91019
2 25728  29.4621 205.8820 0090537 129.1471 231.6610 16.32391155  4722
Ori 3 Delta 3 r                                  201 x 122 km
1 25728U 99024B   99156.88274381  .49999441  95766+0  59445-3 0 91014
2 25728  29.4605 204.9194 0060382 130.6897 229.8365 16.41710985  4746
Ori 3 Delta 3 r                                  168 x 115 km
1 25728U 99024B   99156.94336808  .79264044  36579+1  52628-3 0 91015
2 25728  29.4592 204.4348 0041038 131.4662 228.8866 16.49122181  4752
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Object: #23186 = 94- 43 B = APStar 1 Long March (CZ-3) r 

Decay predictions:
Source   Prediction made    Predicted decay at      Latitude Longitude
               UTC                UTC                  deg      deg

SpaceCom   Jun  3 20:14     Jun  7 20:47 +-3d        21.1 N    19.9 E
SpaceCom   Jun  4 23:41     Jun  7 20:25 +-2d        11.7 N    79.3 W

SatEvo     Jun  4 21:45     Jun  8 07:00 +-1d
SatEvo     Jun  5 12:25     Jun  9 02:14 +-1.3d

Latest elset (25 seconds early on yesterday's prediction):
APStar 1 CZ-3 r                                  896 x 123 km
1 23186U 94043B   99156.21747601  .10138007 -90081-5  45541-3 0  6878
2 23186  26.5494 116.3479 0561174 271.2911  82.3295 15.18758254 67996

SatEvo prediction:
APStar 1 CZ-3 r                                  802 x 122 km
1 23186U 94043B   99157.00205565  .10929868  60451-2  42529-3 0 96873
2 23186  26.5463 110.9068 0496795 280.4184  74.0223 15.34770376 68117
APStar 1 CZ-3 r                                  733 x 121 km
1 23186U 94043B   99157.52034271  .11974504  74496-2  41132-3 0 96875
2 23186  26.5441 107.2388 0449760 286.5717  68.5371 15.46622603 68198

Note: In theory, this rocket should be affected very strongly by the 
transition in atmospheric flow regime as the perigee falls. The effect 
should be for the drag to increase more slowly than would otherwise be 
the case and for the lifetime to be extended. The prediction attempts 
to model this effect (assuming a length of 7.5 m for the rocket). 
Neglecting this effect, I get a decay at Jun 8 12:41 UTC, closer to, 
but still much later than SpaceCom's prediction.
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Alan
-- 
 Alan Pickup | COSPAR 2707:  55d53m48.7s N  3d11m51.2s W   156m asl
 Edinburgh   | Tel: +44 (0)131 477 9144     Fax: +44 (0)870 0520750
 Scotland    | SatEvo page:   http://www.wingar.demon.co.uk/satevo/