By coincidence, I observed 96 72A Norad 24680 at 2:15 UT 1997 05 22 in 8/10th cloud. :-) It was very bright (about 1st magnitude) and very fast. It was also 3 min 25 sec late according to the latest Molczan file. I had run a prediction for it but it was so late, I almost missed it and, as usual these days, observing conditions were terrible. BKH Brian K. Hunter, Department of Chemistry Professor Queen's University bkh@chem.queensu.ca Kingston, Ontario (613)-545-2620 Canada K7L 4R6 44.236N 75.511W 70m ---------- From: Bill Krosney <bkrosney@MBnet.MB.CA> To: SeeSat-L@cds.plasma.mpe-garching.mpg.de Subject: USA 129 (spectacular glint) & QuickSat: questions Date: Thursday, May 22, 1997 3:18 AM Was out observing Friday evening (May 17/97 UT) with a group of students. Thought Id impress them with a few satellite predictions. I ran QuickSat against a Molczan tle file (cs970515) filtering for satellites only brighter than 3rd magnitude. I came up with a handful of sats that with the bright twilight we were observing under were less than impressive. I was upstaged, and caught off-guard by a brilliant sat rising out of the south around 03:35 UT. Easily surpassed Mars in magnitude (Mars is at 0.0) as it glinted for several seconds. I took some good natured ribbing for not being able to id the brightest satellite we saw. Afterwards I ran the cs970515 Molczan file looking for a match. Based on the time (to the nearest minute or two), and direction, the only match I could find was for USA 129 (Norad 24680). These were the elements (twenty-nine days old) from the Molczan file: USA 129 15.0 3.0 0.0 5.1 v 1 24680U 96072 A 97110.88696056 0.00017500 00000-0 18385-3 0 04 2 24680 97.8600 173.9660 0541000 132.5636 227.4363 14.74552770 09 Hoping to confirm this I had a similar pass (same time, and approx altitude and azimuth) for USA 129 last night (May 21/97 03:35 UT). Unfortunately I had better than 9/10 cloud cover. I was just about to give up, turned off my time signal, thinking either I was wrong or had missed it with the cloud cover when I glimpsed it through a hole. Again it flared brighter than Mars for just under two seconds. Approximate altitude and azimuth when it flared was 40deg alt. and 190 deg. azi.. The sun at that time was at azi. 320 deg and alt. -10 deg. Based on the above element set it was running about 3 to 3 and a half minutes late. Some questions: I felt pretty sure this was USA 129. Has anyone observed it recently such that the above elements are indeed running about 3 minutes or more slow? Has anyone observed a bright glint from this sat before? Is USA 129 in a sun-synchronous orbit, based on its inclination (>90 deg) and the fact that it repeated the same ground track almost exactly 4 days later? QuickSat actually selected USA 129 on my short list of sats brighter than 3rd magnitude. Although I ignored it because it predicted a magnitude 18! I can understand the errorneous magnitude prediction because there is no base magnitude for 24680 in the quicksat.mag file. But Im confused why it showed up in the short list. Does QuickSat ignore the magnitude filter if the satellite is not found in the magnitude file? Ive got another good pass coming in a couple of days...if the clouds will just clear! As always...clear skies Bill (long. 97.27, lat. 49.85) ----------