decay watch update: January 5

Alan Pickup (alan@wingar.demon.co.uk)
Tue, 5 Jan 1999 21:34:12 +0000

These SpaceCom decay notices are current or have been issued and 
superseded since my update yesterday:

Object                            Notice issued    Predicted decay
                                       UTC              UTC
     
#25421 = Orbcomm 13 Pegasus r     Jan  4 16:43     Jan  4 22:52 +-4h
#25421 = Orbcomm 13 Pegasus r     Jan  4 20:20     Jan  4 22:49 +-2h
#25421 = Orbcomm 13 Pegasus r     Jan  4 23:20     Jan  4 22:53 +-59m

#25532 = Iridium 2 Delta r        Jan  4 19:09     Jan  7 13:50 +-2d
#25532 = Iridium 2 Delta r        Jan  5 08:53     Jan  7 06:06 +-1d

 #4583 = Meteor 1-6               Jan  4 15:25     Jan  8 13:02 +-2d
 #4583 = Meteor 1-6               Jan  5 14:30     Jan  8 11:59 +-2d

#21148 = Lacrosse 2 r             Jan  4 23:18     Jan  8 23:47 +-2d

#25533 = Sputnik 41               Jan  4 10:29     Jan 11 06:17 +-6d

               -------------------------------

#25421, the Orbcomm 13 Pegasus rocket, kept remarkably close to the 
prediction I posted here yesterday. Three of the four elsets published 
since then show it within 0.5 second of prediction and the final one...

Orbc13 Pegasus r 1.3  1.0  0.0  7.5 d            156 x 135 km
1 25421U 98046J   99004.86106028  .21248528  10889-4  28907-3 0  2583
2 25421  44.8948 190.1496 0016545 324.1314  35.8698 16.47716507 24168

... shows it only 0.75 seconds late. My final analysis indicates decay 
at January 4.947 (22:43 UTC), over Mexico City. This was only ten 
minutes before SpaceCom's decay time and five minutes after it passed 
over Los Angeles.

               -------------------------------

My updated decay predictions and SatEvo-predicted elsets:

   #    Designation    Name               Predicted decay

 25532   98- 66 F   Iridium 2 Delta r      January  7.25+-0.3d
  4583   70- 85 A   Meteor 1-6             January  8.2 +-0.5d
 21148   91- 17 B   Lacrosse 2 r           January  8.4 +-0.6d
 25533   98- 62 C   Sputnik 41             January 10.5 +-1.0d
 25579   98- 74 C   Iridium 11A CZ-2C r    January 21   +-3d
 25065   97- 74 C   ETS-7 H2 r             January 23   +-4d


Iridm 2 Delta r  5.9  2.4  0.0  5.6 d            227 x 173 km
1 25532U 98066F   99006.02343292  .04103345  86330-2  94033-3 0 91417
2 25532  82.4406 246.2333 0041124 115.0719 245.3555 16.27409672  9554
Iridm 2 Delta r  5.9  2.4  0.0  5.6 d            207 x 166 km
1 25532U 98066F   99006.51465075  .06215789  23502-1  96518-3 0 91414
2 25532  82.4388 245.6536 0031844 113.0596 247.2764 16.32312063  9635
Iridm 2 Delta r  5.9  2.4  0.0  5.6 d            174 x 150 km
1 25532U 98066F   99007.00390751  .15341275  15362+0  65621-3 0 91411
2 25532  82.4357 245.0707 0018427 111.0367 249.1604 16.41458189  9714

Meteor 1-6       5.0  1.5  0.0  5.8 v            193 x 187 km
1 04583U 70085A   99006.04868136  .02153608  29324-2  44959-3 0 95491
2 04583  81.0974 354.9262 0004510 175.2633 184.7410 16.31033655550546
Meteor 1-6       5.0  1.5  0.0  5.8 v            177 x 173 km
1 04583U 70085A   99007.02882949  .03683031  93891-2  44562-3 0 95497
2 04583  81.0955 353.5581 0003305 171.3729 188.6328 16.36467596550707

Lacrosse 2 r     9.8  3.0  0.0  5.0              215 x 207 km
1 21148U 91017B   99006.02092887  .02108375  24843-2  83964-3 0 90873
2 21148  67.9486 289.4261 0006208  77.0851 282.9843 16.23320103 64461
Lacrosse 2 r     9.8  3.0  0.0  5.0              200 x 194 km
1 21148U 91017B   99007.00534024  .03304648  66239-2  84745-3 0 90871
2 21148  67.9469 286.1294 0004780  75.7891 284.2640 16.28458692 64622


Alan
-- 
 Alan Pickup | COSPAR 2707:   55d53m48.7s N   3d11m51.2s W   156m asl
 Edinburgh   | Home:   alan@wingar.demon.co.uk    +44 (0)131 477 9144
 Scotland    | SatEvo page:     http://www.wingar.demon.co.uk/satevo/