Decay watch: Dec 16

Alan Pickup (alan@wingar.demon.co.uk)
Thu, 16 Dec 1999 23:05:44 +0000

#19377 = 88- 69 A = Molniya 1-73
  According to SpaceCom, this decayed at Dec 16 00:59 UTC +-1m at 42.0
S, 21.3 W. In fact, The final elset published by SpaceCom...
Molniya 1-73                                     649 x 80 km
1 19377U 88069A   99349.87789194  .99999999  65198-5  57407-3 0  8671
2 19377  62.6240  95.2893 0421790 261.1818 203.3222 15.68196795 93738
is the last of a series which appeared for most of the orbits during the
last day of this object. However, it has an unusually large residual of
30 seconds when compared with an orbital evolution that gives a
reasonable fit to the preceding elsets. Attempts to include it in the
fit give very unsatisfactory results and I am forced to exclude it from
my analysis. I put the re-entry at Dec 16 05:20 +-3h near 61.8 S, 144.0
W, just beyond perigee and close to southern apex over the far-S Pacific
on the final SatEvo-predicted orbit... 
Molniya 1-73                                     303 x 80 km
1 19377U 88069A   99350.17496650 2.48090194  11726+2  73001-3 0 98663
2 19377  62.6130  94.1646 0170152 261.0030  97.0675 16.30488823 93789
A re-entry at about 03:52 UTC near a similar position on the previous 
rev is quite possible. Unless SpaceCom has data that it has not yet
made public, the uncertainty of one minute in the SpaceCom decay time
is surely unjustified.

#25790 = 99- 34 B = QuikScat Titan 2 r
  SpaceCom has issued the first decay notice for this, predicting its
decay for Dec 20 05:33 +-2d. I get Dec 20 13:09 +-1.1d. For the past
week, only one elset per day has been issued for this, all with an
epochs exactly 16 orbits apart. This enters eclipse near 68 deg N
latitude at ~07h local time while northbound. Eclipse exit occurs while
southbound near 26 deg S latitude at ~20h local time.

#25889 = 99- 44 A = Cosmos 2365
  According to SpaceCom, this decayed yesterday. The final elset, one of
four for the same rev, reads...
Cosmos 2365      6.0  0.0  0.0  4.5 d   10       198 x 156 km
1 25889U 99044A   99349.52425032  .39580572  62670-5  35993-2 0  3872
2 25889  67.0895 182.7838 0031778  82.1814 279.2287 16.35861210 19062
This manoeuvred a couple of times over the preceding day or so, its
orbit being raised from 260 x 166 km to 282 x 190 km early on December
14 before being lowered again.

I have updated Decay Watch page at
      http://www.wingar.demon.co.uk/satevo/dkwatch/
with more details for #19377 and #25790.

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/

-----------------------------------------------------------------
Unsubscribe from SeeSat-L by sending a message with 'unsubscribe'
in the SUBJECT to SeeSat-L-request@lists.satellite.eu.org
http://www2.satellite.eu.org/seesat/seesatindex.html