Re: Decaying Cosmos 1172

Bjoern Gimle (b_gimle@algonet.se)
Fri, 19 Dec 1997 21:46:39 +0100

>At 11:21 18/12/97 +0100, Bjoern Gimle wrote:
>>This should be an interesting object until decay. OIG has just posted
>>new elsets, after a gap of 13 days ! Watch for new ones at OIG and
>>Alan Pickup's http://www.wingar.demon.co.uk/satevo/tle/dklist.tle
>>
Tony Beresford:
>I have a 1800Km range pass in an hour or so Bjoern,

could not see it +/- 5 min.

I apologize for not checking the elsets better - the agreement between
elsets 169 and 170, and the moderate increase in ndot over the 13 days
fooled me. If you look at MM, the increase from 2.6 to 6.6 corresponds
to ndot2 of about 0.15, and modifying the elset I posted to fit elsets
171 and 172 within 15 seconds, I had to set ndot2 to 0.196

This leads to an error of about 25 minutes on Dec.18.6

The new SatEvo evolution leads to a decay on Dec.26, unless the Moon
deforms the orbit, or the Sun erupts. The moon is near the apogee line,
so I believe the pull is uniform, and small at this height. I was not
able to make any integrations.

-----------------------------
        SatEvo v0.30
       by Alan Pickup
   alan@wingar.demon.co.uk
-----------------------------

Element evolution for object 80028A  

Predicted decay after    8.5962 days on date = 97360.3236 (1997 December 26)

 Uses Q-factor of 1.000000

Cosmos 1172        = 1                           11178 x 77 km
1 11758U 80028A   97351.72741419  .19600000  69480-2  61082-3 0 91705
2 11758  61.8240 118.7734 4623129 247.1034  58.4936  6.60038177129717
Cosmos 1172        = 1                           10470 x 77 km
1 11758U 80028A   97352.46900155  .21284277  82663-2  61532-3 0 91706
2 11758  61.7670 118.1350 4459898 247.1823  60.4752  6.90321216129763
Cosmos 1172        = 1                           10194 x 77 km
1 11758U 80028A   97352.75646813  .22022649  88663-2  61784-3 0 91705
2 11758  61.7461 117.8752 4393503 247.2152  61.2785  7.02767967129787
Cosmos 1172        = 1                           8993 x 77 km
1 11758U 80028A   97353.98845458  .25915864  12521-1  63473-3 0 91706
2 11758  61.6504 116.6728 4085056 247.3724  64.9876  7.61553697129870
Cosmos 1172        = 1                           8864 x 77 km
1 11758U 80028A   97354.11933291  .26416902  13033-1  63722-3 0 91701
2 11758  61.6405 116.5357 4049646 247.3909  65.4111  7.68402482129888
Cosmos 1172        = 1                           8734 x 77 km
1 11758U 80028A   97354.24904491  .26934014  13577-1  63984-3 0 91707
2 11758  61.6304 116.3979 4013976 247.4095  65.8372  7.75322281129898
Cosmos 1172        = 1                           8606 x 77 km
1 11758U 80028A   97354.37759934  .27416334  11917-1  64138-3 0 91700
2 11758  61.6203 116.2593 3978056 247.4284  66.2657  7.82311395129900
Cosmos 1172        = 1                           8478 x 77 km
1 11758U 80028A   97354.50500637  .27880181  12366-1  64232-3 0 91708
2 11758  61.6116 116.1199 3941958 247.4474  66.6959  7.89356174129917
Cosmos 1172        = 1                           8351 x 77 km
1 11758U 80028A   97354.63127747  .28358438  12884-1  64339-3 0 91708
2 11758  61.6013 115.9797 3905681 247.4667  67.1276  7.96457085129921
Cosmos 1172        = 1                           8225 x 77 km
1 11758U 80028A   97354.75642382  .28851804  13392-1  64460-3 0 91703
2 11758  61.5925 115.8388 3869215 247.4861  67.5610  8.03616323129933

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