Decay watch: May 29

Alan Pickup (alan@wingar.demon.co.uk)
Sat, 29 May 1999 17:53:33 +0100

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Object: #25745 = 99- 28 B = USA 144 Titan 4 r

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

SpaceCom   May 24 21:58     Jun  2 11:36 +-5d        63.4 S    94.0 W
SpaceCom   May 26 06:28     Jun  1 14:00 +-4d        47.1 N     3.3 W
SpaceCom   May 28 11:26     Jun  1 11:29 +-2d        19.2 N   172.6 E
SpaceCom   May 29 13:30     Jun  1 13:04 +-2d         6.9 S   161.8 E

SatEvo     May 25 12:00     Jun  3       +-3d
SatEvo     May 27 19:00     Jun  1 23:00 +-1.4d
SatEvo     May 28 21:25     Jun  1 02:43 +-20h
SatEvo     May 29 16:20     Jun  1 06:25 +-18h

Latest elset by Pierre Neirinck:
USA 144 Titan 4 r                                250 x 188 km
1 25745U 99028  B 99148.89216350  .01710000  00000-0  68365-3 0    09
2 25745  63.3750  77.9827 0046500 177.0536 182.1664 16.20177744    00
Latest elset by Rainer Kracht:
USA 144 Titan 4 r                                249 x 182 km
1 25745U 99028  B 99149.20064118  .01833000  00000-0  61814-3 0    06
2 25745  63.4618  76.4579 0051352 167.4587 192.7322 16.21488715    04

SatEvo prediction from Pierre's elset:
USA 144 Titan 4 r                                233 x 181 km
1 25745U 99028  B 99150.00185275  .02348847  27321-2  67863-3 0 90001
2 25745  63.3736  73.5679 0039800 177.0745 182.9489 16.24598956   186
USA 144 Titan 4 r                                223 x 176 km
1 25745U 99028  B 99150.55535805  .02929912  43891-2  67210-3 0 90003
2 25745  63.3726  71.3540 0035648 177.0851 182.9357 16.27496209   277
USA 144 Titan 4 r                                211 x 170 km
1 25745U 99028  B 99151.04643764  .03789458  77399-2  65643-3 0 90000
2 25745  63.3715  69.3811 0031357 177.0948 182.9234 16.30757387   357

Note: Pierre's latest elset shows this running 15 seconds late (at the
equator crossing) against the SatEvo prediction I posted yesterday. 
However, Rainer's elset has it only 1 second late at the equator
crossing. Comparison is complicated by the fact that the eccentricities
differ markedly and that this is being observed while well north of the
equator.
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Object: #25683 = 99- 20 B = Landsat 7 Delta r

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

SpaceCom   May 26 20:46     May 30 20:26 +-2d        25.7 S   102.5 W
SpaceCom   May 28 19:51     May 30 17:37 +-1d        52.4 S    75.7 W

SatEvo     May 25 19:30     Jun  1 00:00 +-1.2d
SatEvo     May 26 18:00     May 31 10:00 +-1d
SatEvo     May 27 18:00     May 31 09:00 +-0.8d
SatEvo     May 28 21:40     May 31 03:50 +-12h
SatEvo     May 29 16:40     May 31 03:04 +-9h

Latest elset:
Lndst7 Delta r   5.9  2.4  0.0  5.0 d            274 x 139 km
1 25683U 99020B   99149.52905094  .03974273  93384-5  18758-3 0  1362
2 25683 107.5609 276.0922 0102083 241.0998 117.9915 16.24818205  6869

SatEvo prediction:
Lndst7 Delta r   5.9  2.4  0.0  5.0 d            249 x 136 km
1 25683U 99020B   99150.02083180  .05893453  11760-1  20333-3 0 91369
2 25683 107.5591 277.4191 0085696 239.9016 119.2461 16.30108963  6949
Lndst7 Delta r   5.9  2.4  0.0  5.0 d            217 x 130 km
1 25683U 99020B   99150.51085662  .08941104  35588-1  18970-3 0 91368
2 25683 107.5567 278.7523 0065897 238.6973 120.6558 16.37113115  7029
Lndst7 Delta r   5.9  2.4  0.0  5.0 d            141 x 109 km
1 25683U 99020B   99151.05858622  .41129406  12594+1  18207-3 0 91366
2 25683 107.5509 280.2649 0024485 237.3303 122.4331 16.55414959  7112
Lndst7 Delta r   5.9  2.4  0.0  5.0 d            109 x 96 km
1 25683U 99020B   99151.11891855 1.66250943  22708+2  30183-3 0 91363
2 25683 107.5492 280.4350 0010489 237.1765 122.7224 16.64187069  7127

Note: The latest elset shows this to be 7 seconds early against the
prediction I posted yesterday.
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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/