As discussed below, I propose that we consider re-assigning 90079 / 07859A as
06027B / 29250, and expect to find USA 200's Centaur in a similar orbit.
Peter Wakelin discovered 90079 / 07859A on 2007 Dec 25; here are the most recent
available elements:
1024 X 36529 km
1 90079U 07859A 08046.72845030 .00000000 00000-0 00000-0 0 04
2 90079 62.3975 315.1772 7057374 274.2760 85.7241 2.17595297 00
Since its mean motion was not close to the operational value for a Molniya
payload, ~2.006 rev/d, it was obvious that it was either a decommissioned
payload, or a rocket body. It is sufficiently bright to be either, but I now
suspect that it is the latter, specifically, the 2nd stage of the Delta IV
rocket that launched USA 184 (06027A / 29249).
Below is USA 184's approximate orbit at its first apogee, on 2006 June 28 UTC:
USA 184
1 71001U 06179.41131020 .00000000 00000-0 00000-0 0 07
2 71001 62.4000 47.0000 7090000 266.5070 180.0000 2.10000000 08
Propagating 90079 back to the same epoch (using SDP4) yields RAAN of 48.6 deg,
and argument of perigee of 267.2 deg, in close agreement with USA 184's orbit.
The orbit of 90079 also is similar to that reported to the U.N. for 06027B:
http://www.unoosa.org/pdf/reports/regdocs/ser495E.pdf
90079 06027B
mean motion (rev/d) 2.17595 2.17588 (1440 min/d divided by 661.8 min/rev)
inclination (deg) 62.4 62.3
perigee height (km) 1079 1024
apogee height (km) 36487 36529
mean height (km) 18783 18777
If 90079 is 06027B / 29250, then we can expect to find USA 200's Centaur stage
(08010B / 32707) in a roughly similar orbit, for which I suggest the following
search elements:
USA 200 Centaur
1 70000U 08073.46717570 .00000000 00000-0 00000-0 0 05
2 70000 62.3000 39.5921 7035500 266.5042 17.9978 2.17588000 06
Note the similarity with the payload's search elements:
USA 200
1 71001U 08073.68144909 .00000000 00000-0 00000-0 0 01
2 71001 62.4000 39.5602 7090000 266.5070 180.0000 2.10000000 02
I have assumed they are in roughly the same plane; in fact, either one or both
planes could be out by at least a couple of degrees. I hope that at least the
along-track spacing will be reasonably accurate.
Ted Molczan
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