Decay watch: Foton 12 rocket

Alan Pickup (alan@wingar.demon.co.uk)
Fri, 24 Sep 1999 23:59:32 +0100

Because of the interest in the possibility that this decayer might
oblige with a re-entry over the USA, I am posting below the whole of my
latest decay watch notice, as being uploaded to my Decay Watch page at
      http://www.wingar.demon.co.uk/satevo/dkwatch/

Object: #25903 = 99- 48 B = Foton 12 Soyuz-U rocket

Notice prepared: 1999 September 24 22:40 UTC

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

SpaceCom   Sep 21 08:15     Sep 25 08:15 +-2d         4.0 S    37.6 E
SpaceCom   Sep 22 11:07     Sep 25 04:47 +-2d         0.2 N   107.2 W
SpaceCom   Sep 23 05:27     Sep 25 05:46 +-1d        54.3 N   103.3 E
SpaceCom   Sep 24 03:57     Sep 25 04:26 +-15h       61.6 N   173.7 W
SpaceCom   Sep 24 15:56     Sep 25 03:54 +-8h        30.1 S    69.0 E
SpaceCom   Sep 24 21:32     Sep 25 03:12 +-4h        23.0 N    95.7 W

SatEvo     Sep 19 21:00     Sep 25 03:15 +-1.7d
SatEvo     Sep 21 18:00     Sep 25 06:12 +-1d
SatEvo     Sep 22 18:00     Sep 25 05:28 +-15h
SatEvo     Sep 23 21:40     Sep 25 01:30 +-8h
SatEvo     Sep 24 18:40     Sep 25 03:58 +-3h         0.0      84.3 E
SatEvo     Sep 24 22:40     Sep 25 03:58 +-100m       0.0      84.2 E

Latest elset:
Foton12 Soyuz r  7.4  2.4  0.0  5.5 d   10       176 x 149 km
1 25903U 99048B   99267.80136088  .10806535  88070-5  45206-3 0   487
2 25903  62.7712 148.8182 0020868 109.4121 251.2412 16.41166149  2424

SatEvo prediction:
Foton12 Soyuz r  7.4  2.4  0.0  5.5 d   10       172 x 146 km
1 25903U 99048B   99267.86219475  .13208769  12276+0  43698-3 0 90484
2 25903  62.7707 148.5641 0019482 109.4251 250.7855 16.42503645  2432
Foton12 Soyuz r  7.4  2.4  0.0  5.5 d   10       166 x 143 km
1 25903U 99048B   99267.92304070  .15917134  18915+0  39068-3 0 90484
2 25903  62.7702 148.3094 0017888 109.4381 250.7553 16.44264065  2447
Foton12 Soyuz r  7.4  2.4  0.0  5.5 d   10       159 x 138 km
1 25903U 99048B   99267.98381385  .20385328  33568+0  35274-3 0 90480
2 25903  62.7695 148.0543 0015980 109.4512 250.7215 16.46444374  2452
Foton12 Soyuz r  7.4  2.4  0.0  5.5 d   10       150 x 132 km
1 25903U 99048B   99268.04449303  .29617137  80419+0  32909-3 0 90487
2 25903  62.7686 147.7987 0013512 109.4643 250.6818 16.49398090  2469
Foton12 Soyuz r  7.4  2.4  0.0  5.5 d   10       134 x 122 km
1 25903U 99048B   99268.10503160  .59557984  35727+1  33606-3 0 90480
2 25903  62.7672 147.5423 0009707 109.4774 250.6275 16.54351759  2478

Note: The latest elset (above) shows the rocket running only 0.02 sec
late against the prediction I made four hours ago. My prediction for 
the decay time is unchanged, but the uncertainty is reduced to little
more than one orbit. I believe re-entry is most likely near a 
northbound equator crossing at the end of the orbit predicted from the 
final predicted elset above. This would put it over the Indian Ocean, 
SE of Sri Lanka. However, earlier in that orbit it passes over SE 
China (02:38 UTC), S Korea (02:42), Vladivostok (02:43) and the Bering 
Sea. It then sweeps SE-wards over Anchorage, Alaska, at 02:55, NE 
of Vancouver (03:00), then across the W USA from Spokane, Washington, 
at 03:01 to San Antonio, Texas, at 03:07. Perigee occurs in the 
vicinity of Vancouver, improving the chance of decay over this stretch 
of the orbit. Indeed, SpaceCom's latest prediction is for decay only
a few hundred km S of Townsville, Texas. The track continues to the 
equator W of Ecuador (03:15), across Argentina (~03:25) and the S 
Atlantic and far to the S of S Africa before swinging N again over 
the Indian Ocean. There is a reducing possibility of a decay on the 
on the previous orbit, in which it crosses the E USA from northern 
Minnesota at 01:33, over Chicago at 01:35, to S Carolina at 01:38.

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/