FW: 92-83A found again

Ted Molczan (molczan@fox.nstn.ca)
Sun, 16 Jun 1996 12:38:48 -0400

Rainer Kracht wrote:

>USA 86 (92-83A, 22251) was found again by Russell Eberst.

>USA 86        
>1 22251U 92 83  A 96167.00000000  .00020000  00000-0  19754-3 0    07
>2 22251  97.8745 278.2592 0541368 270.0251 329.2145 14.75564537    06

>USA 116       
>1 23728U 92 83  A 96167.00000000  .00000097  00000-0  64612-5 0    06
>2 23728  97.7612 275.8155 0427166 260.3873  52.5662 14.54459267    07

Now the problem will be to determine, if possible,
"which one is which". The only precedent we have for
a Kh remaining in orbit during and after the launch
of its replacement is 84122A, which was replaced by
88099A in Nov'88.

When both objects were recovered in the spring of 1989, 
we found that one of them was in almost exactly the standard
orbit, and the other had a lower than standard apogee,
by more than 100 km, and was several deg out of plane. 
Initially, everyone assigned 88099A to the non-standard 
orbit. However, eventually I performed  an analysis that 
showed that the reverse was true - 84122A was simply decaying 
gradually from the standard orbit.

The present situation cannot be resolved quite so easily,
because the object in the non-standard orbit, appears to
be in a designed orbit, judging by its 2 day ground-track
repetition rate.

Also, I wonder whether or not 95066A represents a replacement
or an augmentation. I suspect the former, because I cannot
think of a good reason to maintain two Kh's in nearly the
same plane, with nearly identical argument of perigee. Perhaps
92083A has suffered some systems failures that will cause it
to have a shorter than planned life, or which have affected
one or more key sensors. Those would be good reasons for
replacing it with a fresh sat, but retaining it as a back-up.

The present orbits suggest that the two objects were last
coplanar sometime in mid-April. Both are drifting west, but
95066A is drifting far more rapidly than the 92083A. I have
wondered whether or not it is being moved west to occupy the
plane of the apparently de-orbited 88099A, but that would
take about 30 months at the present drift-rate. Kh's can operate
up to 7.5 years (based on 88099A), so there is time to do so.
But the owners must have known that 88099A was nearing the
end of its life when they launched 95066A into the much
younger 92083A's orbit. Maybe 92083A has "healed itself" or
"been healed" of its problems, freeing either it or 95066A to 
be re-located. Seems awfully far-fetched!

My best guess is that we have the identities reversed, so
the 92083A is in the non-standard orbit, in the role of
an in-orbit back-up. It will be allowed to drift perhaps
10 degrees west of 95066A, to provide some ground-track
diversity. I do not suggest that we change the identity
assignments based on my guess. Perhaps the true situation
will become apparent with the passage of time - and with the
continued excellent work of the observers and orbital analysts.

bye for now