Re: epochs in the future?

Philip Chien (kc4yer@amsat.org)
Thu, 13 Mar 1997 23:08:07 -0500

Mike McCants <mikem@fc.net> said:

>Yes, of the really high objects, most are lost, but the following
>5 remain:
>
>1 13901U 83020A   97073.26759740 -.00002521  00000-0  00000+0 0  7610
>2 13901  44.6340  16.4330 8621978 323.9560  26.0900  0.24286200  2084
>
>1 14069U 83041C   97059.79946914 -.00000175  00000-0  10000-3 0  7733
>2 14069  14.6030  44.2924 1682813 232.6849 110.8604  0.84341462  8846
>
>1 20413U 83020D   97071.56690600 -.00002293  00000-0  00000+0 0  9614
>2 20413  40.4400  22.3730 8757140 318.3160 335.3250  0.24727000  2099
>
>1 23414U 94079B   97069.32196990 -.00000386  00000-0  00000+0 0  1879
>2 23414  29.5800 346.9640 8907593 271.3370  11.7880  0.50008300  5833
>
>1 23632U 95039A   97072.95002340 -.00000242  00000-0  00000+0 0  1204
>2 23632  70.8580 248.0170 7561561 327.9680  42.3720  0.26415200  1564

The background behind these particular objects is interesting.  83 20A and
95 39A are Russian scientific satellites in very high orbits, and 83 20D
would be the upper stage (Proton?) of the 83 20A launch.

94 79B is the Centaur upper stage from the Orion 1 launch which was put in
to a very high altitude ellipitcal orbit.  (I think there are one or two
additional Centaurs with very high apogees).

83 41C is the one which puzzles me.  This is a GOES geosynchronous weather
satellite launch on a Delta 3914 launch vehicle.  The A object is the
satellite which is still in geosynchronous orbit, but with a fairly high
inclination.  The B object is the second stage which has almost certainly
reentered by now.

The C object is the third stage.  On a 3914 model it's a TE-334 (or
something like that) solid motor which is spin stabilized.

The satellite itself is one of the early Hughes spin stabilized weather
satellite busses.

So why should 83 41C be in such an extraordinarily high orbit?  Quick and
dirty calculations -

32978.210 km perigee
48904.061 km apogee

Both well above geosynchronous altitude.  Was this an unusual launch
profile which was used to test out ways of saving propellant?  (doubt it
because no techniques like this were used for quite some time)

Did the stage 'drift' upward due to lunar-solar pertubations?  And if so -
why only this stage and no other Delta 3914 upper stages?

I'm curious ...



Philip Chien [M1959.05.31/31.145//KC4YER@amsat.org]