Re: FW: 92-83A found again

John Pike (
Sun, 16 Jun 1996 13:37:11 -0400

At 12:38 PM 6/16/96 -0400, Ted M. wrote:
>Rainer Kracht wrote:
>>USA 86 (92-83A, 22251) was found again by Russell Eberst.

Life continues to be interesting.....

>I wonder whether or not 95066A represents a replacement
>or an augmentation. I suspect the former

About the only close precedent we have for trying to reverse engineer this
situation is the Defense Support Program, which in the old days was regarded
as having a 3+2 constellation of three primary and two backup spacecraft. At
that time, we had imagined that the two backup spacecraft were just sorta
sittin there cooling their heels on the off chance that they might be
needed. It is now pretty clear that by around the time of Desert Storm the
DSP constellation was operating in a 5+0 mode, with all five birds doing
more or less front line service.

If we had decent elsets for the DSP stuff at GEO, we could probably continue
to identify "replacement" activity as newly launched spacecraft assumed the
"primary" orbital slots with the older spacecraft moving to the "secondary"
slots, but from a user perspective these distinctions seem to have
substantially diminished over time.

Perhaps we are seeing something like this with KH.

>I cannot
>think of a good reason to maintain two Kh's in nearly the
>same plane, with nearly identical argument of perigee.

I confess that I am still in the process of moving all my stuff over to
Win95, so I don't have my sat.track software up and running at the moment,
so I am having a bit of difficulty envisioning what is going on here, so can
someone review the bidding for me as to just what the orbitological
relationship is between these two birds [ie, what sorta passes are the two
birds generating relative to each other].

My general analytical approach is to assume that whatever we are seeing is
"normal" and to try to make sense of it from that perspective, and to only
resort to "abnormal" assumptions [ie, obviously a major malfunction] when
all else fails. This has led me astray in the past [ie, SDS-II /1 ], but it
seems to be a pretty good starting point.

If the current orbitology is generating two closely successive and
repetitive passes in more or less short order then it would seem to provide
some interesting moving target indicator possibilities in terms of scene
subtraction to see moving vehicles. The scenes would of course not be
entirely identical, but it would seem that some serious pixel.bashing [those
supercomputers at D-CEETA at Ft Belvoir must be doing something for a
living] could produce reasonably similar scenes in which most of the
inter-scene change might be due to moving vehicles, particularly if some
semi-fancy algorithms were applied to exclude broad area effects such as
cloud cover.

Or, if the orbitology is producing some other relationship between the
coveragge of the two birds, perhaps other hypotheses might be adduced.

>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.

These are useful hypotheses, but it might also be useful to attempt to
contemplate just what this might consist of, as on the face of it I am a bit
hazy as to just what might happen to a KH that would render it partially
functional [it sorta seems to me that either the thing is working or it
isn't, but maybe I am missing something here, as in, perhaps there could be
a problem with the data links that would permit it to do direct downlink
even though the SDS bent-pipe link is broken, or something ....]

>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.

These birds also have a lotta gas onboard, so if they wanted to do something
like this, I think we would be seeing a somewhat less leisurely repositioning.

>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.

Yes, precisely.

>Maybe 92083A has "healed itself" or
>"been healed" of its problems, freeing either it or 95066A to 
>be re-located. Seems awfully far-fetched!

Yes, this requires too many assumptions....

>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.

This sounds pretty good, but we still need to address just what we mean by
"an in-orbit backup"

>It will be allowed to drift perhaps
>10 degrees west of 95066A, to provide some ground-track

This is a testable hypothesis.

>continued excellent work of the observers and orbital analysts.

Yes, indeed!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!


John Pike
Director, Space Policy & CyberStrategy Projects
Federation of American Scientists
307 Massachusetts Ave. NE
Washington, DC 20002
V 202-675-1023,   F 202-675-1024,