Re: Decay Watch: #21892

Alan Pickup (alan@wingar.demon.co.uk)
Sun, 22 Mar 1998 09:08:43 +0000

Regarding his binocular obs of this GPS PAM-D, Ron Lee
<ronlee@pcisys.net> writes
>...
>21892
>1 21892U 92009C   98080.88376902  .02011925 -67434-6  80885-3 0  5618
>2 21892  34.4286   7.5870 0932503 256.3201  93.2584 14.2112852414899
>...
>Just looking at the elset with a mean motion of 14.2, sure seems odd
>that it is due to decay around 21 April.

But its perigee is around 150-155 km and it is certainly feeling the
drag. It passed through mm=12.0 on December 21, mm=13.0 on February 14
and mm=14.0 on March 16. An evolution to decay on April 21 has it
reaching mm=15.0 on April 9 and mm=16 about 28 hours before re-entry. In
fact, my prediction of April 21 (as for many of the dates in my latest
decay list) assumes that the mean atmosphere density will decrease a
little from its recent high value - if current conditions continue, its
decay could occur a few days earlier still. I include current elsets for
this in both dklist.tle and select.tle, available via my WWW page.

Alan
-- 
 Alan Pickup | COSPAR site 2707:   55d53m48.7s N   3d11m51.2s W    156m asl
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