Re: Decay watch: Molniya 3-11 & Mir VDU
Alan Pickup (alan@wingar.demon.co.uk)
Wed, 2 Dec 1998 17:47:45 +0000
Thanks for all the observations of Molniya 3-11. In fact, it is decaying
more rapidly than I expected and the decay should help to improve
SatEvo's performance for such extremely high-drag objects. The current
elset:
Molniya 3-11 728 x 98 km
1 11240U 79004A 98336.62432160 .99999999 99048-5 24553-2 0 855
2 11240 61.9440 334.5503 0463804 285.5206 69.9709 15.51169661149689
shows it almost 12 minutes early against yesterday's prediction. It also
indicates a higher perigee than elset over the last five days.
I now show decay at December 2.80 (19:15 UTC) with a greater chance of
coming one perigee earlier (at ~17:45) than on the following orbit.
Prediction, with perigee lowered to a more likely level:
Molniya 3-11 615 x 89 km
1 11240U 79004A 98336.68856110 2.31857110 44767+1 17605-2 0 90854
2 11240 61.9363 334.3048 0391002 285.5484 70.1697 15.72451994149690
Molniya 3-11 405 x 89 km
1 11240U 79004A 98336.75175850 4.05852798 18653+2 23426-2 0 90851
2 11240 61.9260 334.0525 0239116 285.5771 71.7965 16.09948985149708
--------------------------------------------
OIG has been silent on the Mir VDU since issuing the elset yesterday...
Mir VDU 4.0 0.0 0.0 6.5 d 188 x 182 km
1 25294U 86017MQ 98335.85419327 .04257364 12175-4 68134-3 0 2710
2 25294 51.6248 255.4897 0005166 130.0687 230.0985 16.32877601 36976
... which has it 9 seconds late on the forecast I posted yesterday. My
latest analysis suggests that decay may be delayed until a southbound
equator crossing December 2.80 (19:15 UTC), the same time as the Molniya
decay above, but this is still uncertain by more than four hours.
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/