Decay watch: May 27

Alan Pickup (alan@wingar.demon.co.uk)
Thu, 27 May 1999 20:37:05 +0100

SpaceCom has issued no further elsets for the decaying Titan...
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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

SatEvo     May 25 12:00     Jun  3       +-3d
SatEvo     May 27 19:00     Jun  1 23:00 +-1.4d

Latest elset (from Pierre Neirinck via Rainer Kracht):
USA 144 Titan 4 r                                268 x 199 km
1 25745U 99028  B 99147.16107100  .01096472  00000-0  63770-3 0    05
2 25745  63.3642  84.7284 0052677 167.4918 192.4329 16.14895721    09

SatEvo prediction:
USA 144 Titan 4 r                                261 x 195 km
1 25745U 99028  B 99148.02749965  .01245538  65973-3  63562-3 0 90002
2 25745  63.3635  81.3117 0049399 167.5107 192.6121 16.16918893   142
USA 144 Titan 4 r                                256 x 193 km
1 25745U 99028  B 99148.52207146  .01353477  80340-3  63381-3 0 90003
2 25745  63.3631  79.3567 0047392 167.5216 192.5961 16.18202560   225
USA 144 Titan 4 r                                251 x 191 km
1 25745U 99028  B 99149.01623376  .01486800  10154-2  63214-3 0 90002
2 25745  63.3626  77.3995 0045267 167.5326 192.5797 16.19603477   302

Note: The SatEvo predictions are based entirely on Pierre's elset. 
A fit including the earlier SpaceCom elsets leads to an elset with 
higher eccentricity and drag, nearly identical mean motion, and decay
at June 1 11:00 UTC +-1.3d.
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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

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

Latest elset:
Lndst7 Delta r   5.9  2.4  0.0  5.0 d            333 x 150 km
1 25683U 99020B   99147.67397540  .02725187  91108-5  32700-3 0  1268
2 25683 107.5636 271.1600 0138122 243.3097 115.4136 16.12040977  6561

SatEvo prediction:
Lndst7 Delta r   5.9  2.4  0.0  5.0 d            323 x 149 km
1 25683U 99020B   99148.04611688  .02753232  17074-2  30562-3 0 91264
2 25683 107.5629 272.1436 0131485 242.4219 116.2364 16.13906196  6626
Lndst7 Delta r   5.9  2.4  0.0  5.0 d            293 x 146 km
1 25683U 99020B   99149.03615881  .03432587  30962-2  27362-3 0 91266
2 25683 107.5608 274.7750 0111537 240.0465 118.8415 16.19963966  6789

Note: The latest elset shows this running 2.6 seconds early against
the SatEvo prediction I gave 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/