New (Old?) Flasher?
Ed Cannon (ecannon@mail.utexas.edu)
Fri, 29 Aug 1997 06:55:05 -0500
Wednesday night while Mike McCants and I were tracking Iridium 4
(97-20E/27496 -- no flash), another one appeared in the field going
the opposite direction, and we followed it. In a few seconds Mike
said, "Is that thing flashing at us?" It was, and he timed the
period at 1.9 seconds. I've just spent some hours trying to ID the
object with alldat.tle and molczan.tle elements, and the best
candidate I've found is 73-86CD:
30.314 97.866 920. BCRC, Austin, Texas 2000 9.9 20 F F T T T
*** 1997 Aug 27 Wed evening *** Times are PM CDT *** 2044 621
H M S Tim Azi Al C Dir Mag Dys F Hgt Shd Rng EW Phs R A Dec
07085 73 86CD
10 6 55 .0 226 35 65 22.7 0 4 934 612 1389 .7 86 1635 -11.9
10 6 57 .0 226 35 65 22.7 0 4 934 613 1386 .7 86 1634 -11.6
10 6 59 .0 226 35 65 22.7 0 4 934 614 1384 .7 86 1634 -11.4
10 7 0 .0 226 36 66 22.7 0 4 934 616 1382 .7 86 1633 -11.1
24796 Iridium 4 97 20E
10 6 55 .0 225 37 233 21.3 0 9 484 97 736 1.2 84 1641 -10.4
10 6 57 .0 225 37 232 21.3 0 9 484 95 740 1.2 84 1641 -10.9
10 6 59 .0 224 37 232 21.3 0 9 484 94 744 1.2 84 1642 -11.4
Here are the 73-86CD elements for the above predictions:
07085
1 07085U 73086CD 97240.04563599 -.00000031 +00000-0 +10000-3 0 07972
2 07085 102.1722 279.5789 0095866 227.6880 131.6047 12.57993746092210
The July 1997 SSR says the RCS of 73-86CD is 0.11. I'm very skeptical
that such a small object at a range of almost 1400 miles (2240 km) could
have been the flasher we saw -- but I didn't find a better candidate.
I noticed in the online flash database some reports in 1975 for 73-86DC
(07138, RCS=0.62), another fragment from the same bunch of Delta 1 debris
objects.
For what it's worth, the second-best candidate was 65-48N/21945, a Transit
5B-6 debris object with an RCS of 0.003!
Ed Cannon
Austin, Texas, USA
30.3086N, 97.7279W, 165m