#22585 Cosmos 2238 decay

Bjvrn Gimle @JAR (@JAR")
Thu, 01 Dec 94 17:02:01 -0800

Dec.09? decay of Cosmos 2238 
Cosmos 2238 #22585 1993-18A has had quite unusual orbit changes.
First, it has  been station-keeping with  #22709 and #22643,  in
the  same  orbital  plane,  and  with  mean  motions essentially
constant around 15.520.  The small orbit  changes appear not  to
have been short rocket pulses  - several times MM has  decreased
over several  elsets, and  the increases  have also  been slower
than expected. On about day  267 it left the circular  orbit, to
one with MM=15.84, and started  decaying, but with an MMdot2  of
only .00048. About  day 313, MMdot2  suddenly jumped 6-fold,  to
the normal value of .00287.  Since then, it has been essentially
normal, indicating  normal uncontrolled  descent, but  it was 40
seconds early  on Dec.1,  from an  elset only  2.0 days old, and
only 5 seconds off in the middle. 

Right now, it has  excellent visibility here near  60N latitude,
but it will become more difficult  closer to the decay - I  hope
you will have better chances of  following it to the decay -  it
is bright, around +2.

For the periods  around the orbit  changes, days 267  and 313, I
lack crucial  elements -  I have  issues 516,527,528,549-552 and
616,623,626,635,649-654.  If  you  have  one  or  more  of those
missing, please upload or post them  as mail.  Also if you  make
any observations, please !
Element set number = 3
1 22585U 93018A   94335.21831221  .00788042  69977-5  73937-3 0  6965
2 22585  65.0063 124.7827 0069696 239.7652 119.6648 16.06466467 95000