Phillip Clark wrote: > Ted posted some comments on my behalf about my belief that the CCDs > (and probably other equipment) in the FSW equipment modules (EM) > continue to operate after the descent module returns to Earth. > On the FSW-0 and FSW-1 flight the EM would be in orbit for at least > a week after the descent craft returned: for the FSW-2 and FSW-3 > missions the EM is in orbit for longer periods. I would be > interested if there are visual observations as to whether the Ems > remained stable and didn't become "flashers" after the descent craft > returned. > > OK, we know that the FSW-3 #2 EM is flashing, after losing attitude > control, but what about the one from FSW-3 #1, the FSW-2 series or > even FSW-1 series... I used three primary sources in my search for observations: 1. The Belgian Working Group for Satellites' Photometric Periods of Artificial Satellites "PPAS" database, specifically, PPAS11-09, located on Mike McCants' website: http://users2.ev1.net/~mmccants/ppas/index.html 2. My archive of Russell Eberst's observations since 1989 Aug. 3. The SeeSat-L archive: http://satobs.org/seesat/seesatindex.html#Arch I found only one PPAS observation of an FSW piece from 1975 through 2003. It was by Jean-Pierre Rohart, of Wormhout, France, of FSW-2 3 (96059A / 24634), which was launched 1996 Oct 20. Jonathan's Space Report states that 96059A, "landed in China Nov 4", apparently referring to its descent module: http://planet4589.org/space/log/log.1996 USSTRATCOM's satcat states that 96059A decayed 1996 Dec 03, apparently referring to its equipment module, which remained in orbit after the return of the descent module. The final elset is in agreement with that date: 1 24634U 96059A 96338.21358451 .10976792 90154-5 59975-4 0 1587 2 24634 63.0183 271.8643 0009298 112.7233 247.6690 16.54634359 7096 Besides the payload and its 2nd stage rocket, USSTRATCOM catalogued a piece of debris (96059C), with a RCS (radar cross-section) of 0.42 m^2, which is interesting because the epoch of the one and (apparently) only elset in on the date the decent module landed: 153 X 473 1 24644U 96059C 96309.34412794 +.30092023 +75539-5 +40968-2 0 00016 2 24644 062.8803 027.5661 0238849 094.8971 267.9365 15.88259486000035 Could this have been the decent module? The orbital elements seem implausible, when compared with that of the spacecraft: 177 X 338 1 24634U 96059A 96309.27741811 .00214054 81308-5 80507-4 0 644 2 24634 63.0382 27.5587 0121719 143.1119 217.8483 16.08345428 2419 The closest conjunction between the orbits occurred on 1996 Nov 04 near 02:39 UTC, over 55.6 N, 77.3 E. However, 96059A was 190 km high, and 96059C was 167 km high. Perhaps the 96059C elset was inaccurate, or totally spurious; I don't know. In any case, the main subject of interest is the equipment module, and getting back to Jean-Pierre Rohart's PPAS report, we see that he observed it on 1996 Nov 21, 17 days after the decent module separated, and that its brightness was steady: 96- 59 A 98-11-21 17:15:20 RO mag 5 almost S Russell Eberst observed it twice. First on 1996 Nov 30, as it passed through the penumbra into eclipse, as denoted by the optical behaviour code, E. Perhaps Russell's field notes indicate whether or not it had been steady throughout the pass. Russell's second obs was on 1996 Dec 01 UTC, 2 days before decay, and the object was steady in brightness: 9605901 2420 19961130 172402.65 001817+324804 6.8 6.8 0 E 9605901 2420 19961201 165236.29 220253-004532 1.9 1.9 0 S 9605901 2420 19961201 165254.83 234053+100053 1.4 1.4 0 S (The above is not a new obs format; it is merely the way I store Russell's obs in my archive.) So it appears that FSW-2 3's equipment module remained stable in solo flight. The only other FSW-related observation I found was by Russell Eberst, of FSW-3 1 (2003-051A / 28078), launched 2003 Nov 03. Its equipment module re-entered 2003 Dec 18. Jonathan McDowell reported that the reentry vehicle, "separated from the main satellite at around 0142 UTC on Nov 21 and landed in Sichuan province at 0204 UTC.": http://www.planet4589.org/space/jsr/back/news.514 About 26 h later, Russell observed FSW-3 1's equipment module, steady in brightness: 0305101 2420 20031122 060434.30 160721+450206 5.2 5.2 0 S Regarding FSW-1 #5 (99063A / 22859), Phillip wrote: > ... to me it is not clear whether the object which > Russell observed as being steady on October 22, 1993 was the > EM that decayed on October 28 or whether it was the descent > module in the eccentric orbit that was steady on > October 22 and then flashing (tumbling) on November 25. > Clarifications would be greatly appreciated ! A check of the obs against the elements confirms that the steady object of 1993 Oct 22 was the EM, in the following orbit: 1 22859U 93063A 93293.78016238 .00743978 49900-4 35208-3 0 2402 2 22859 56.9432 33.4460 0041782 156.7179 203.5542 16.18646867 2001 Ted Molczan ------------------------------------------------------------------------- Subscribe/Unsubscribe info, Frequently Asked Questions, SeeSat-L archive: http://www.satobs.org/seesat/seesatindex.html
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