ETS-7 (97 74A,B,C,D) Mixup
Mike McCants (mikem@fc.net)
Tue, 16 Dec 1997 12:48:04 -0600 (CST)
> COSPAR/WWAS USSPACECOM NUMBER
>SPACECRAFT INTERNATIONAL ID (CATALOG NUMBER) LAUNCH DATE,UT
>
>ETS-7 (CHASER+TARGET) 1997-074B 25064 27 NOVEMBER 1997
>UNKNOWN (DEBRIS ?) 1997-074C 25065 27 NOVEMBER 1997
The object 97 74C was observed last night to be tumbling between
magnitude 0 and 3 with a period of about 13 seconds. It seemed
to be a "smooth" tumble, like a rocket body.
The object 97 74A was observed the last 2 nights as magnitude 2.5
and steady.
The object 97 74D was observed the last 2 night as magnitude 4 or
5 and steady most of the time, but on each night one "slow flash"
to magnitude 0 or -1 was seen. The time at maximum was about
1 second compared to an observation time of 40 to 60 seconds.
I failed to see 97 74B last night.
Note that object 97 74C has an inclination of 34.5, while the other
three have an inclination of 35.0.
Also the D object has rather larger drag term than the A or C
objects. This indicates to me that it has a larger area to
mass ratio.
My opinion is that the H2 upper stage left TRMM and the D debris
piece in the lower orbit, boosted ETS-7 to a higher orbit, and
then did a plane change maneuver as a test and/or avoidance
maneuver. That would mean that C is the upper stage and D is debris.
Mike McCants
1 25063U 97074A 97349.43386087 .00032108 00000-0 21314-3 0 241
2 25063 34.9953 291.2374 0002685 264.4855 95.5577 15.74386063 2759
1 25064U 97074B 97349.49680074 .00006734 00000-0 16827-3 0 228
2 25064 34.9708 296.6417 0105304 350.8998 8.9817 15.33795340 2667
1 25065U 97074C 97349.24669485 .00023703 00000-0 43807-3 0 161
2 25065 34.5450 298.2989 0116074 350.2188 9.6269 15.40859158 2622
1 25066U 97074D 97349.22341906 .00115602 00000-0 10096-2 0 203
2 25066 35.0038 293.3622 0009870 114.3464 245.8289 15.67543686 2702