Soyuz rocket (97- 3B) - when was decay?

Alan Pickup (alan@wingar.demon.co.uk)
Sat, 15 Feb 1997 13:13:43 +0000

The deathly silence on this subject since the fateful night of February
12/13 suggests that no SeeSaters observed the decay of this object. The
final OIG elsets for it were:
Soyuz-U                                          162 x 151 km
1 24718U 97003B   97043.91053648  .07955898  12488-4  29296-3 0   260
2 24718  51.6102 350.0344 0008494  94.2477 265.0550 16.43604969   388
Soyuz-U                                          154 x 145 km
1 24718U 97003B   97043.97145284  .16844357  12578-4  37810-3 0   228
2 24718  51.6103 349.6881 0006902  85.1998 275.0846 16.46100704   399
Soyuz-U                                          150 x 138 km
1 24718U 97003B   97044.03211670  .07210963  12521-4  10000-3 0   230
2 24718  51.6190 349.3748 0009367 138.4661 221.7945 16.48392481   408
Soyuz-U                                          141 x 131 km
1 24718U 97003B   97044.09270681  .22144272  12761-4  19081-3 0   244
2 24718  51.6110 348.9966 0007906  69.9357 290.4334 16.51368987   418

The these elsets showed it running 0.7s, 2.1s, 5.0s and 15.7s late on my
SatEvo predicted evolution posted here that (UK) evening. A simple 15%
decrease in the initial drag term of the evolution gives me residuals of
0.3s, 0.3s, 0.0s and 1.6s for the same four elsets and leads to a decay
at 03.19 UT on the 13th. In fact, I suspect decay occurred between 03.00
and 03.19 as the rocket followed a track over the SE Atlantic from
Ascension I. over Cape Town and then onwards to Kerguelen in The S
Indian Ocean.

Thanks to all those who kept watch, and better luck next time.

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    | Royal Observatory: A.Pickup@roe.ac.uk +44 (0)131 668 8224