As Ed Cannon wrote, I arrived at BCRC about 01:45UT (all times Jan 16, 2002 UT) and I spotted the combined Milstar 5/Centaur Rk object about 02:01UT about 1 minute late on an elset that I generated for the transfer orbit (based on an elset that Ted Molczan sent me for the original target launch time). The 02:00 prediction from BCRC (30.315N, 97.866W, 280m) was altitude 48, azimuth 263, range 3000 miles. My estimated magnitude at this point was 5.5, but my magnitude estimates are always too bright. A magnitude of 6.0 would produce a Quicksat intrinsic magnitude of 1.5 and a Molczan intrinsic magnitude of about 2.5. I tracked the object for 15 minutes as it rose rapidly to altitude 81 and went just to the south of my zenith. At 02:30UT it was alt 69, azi 121, range 7300 miles and estimated magnitude 6.7 (probably about 7.0). Ed saw a flash at 02:33 through the 8-inch and I looked through the 12x80 finder scope. We saw a flash at 02:33:25 that I estimated at about -2 magnitude. Ed saw another minor flash at 2:37:30. At 02:46:34, I saw a flash that I estimated was magnitude 4.5. I estimated the object magnitude as 7.2. This was alt 63, azi 117, range 9500 miles. We tracked the object for the next few hours. We noted flashes at 03:43:40, 03:49:40, 03:55:39, 04:10:03, 04:12:25, 04:36:40, 04:39:42, 04:42:39, 04:45:38, 04:48:57. The object was changing from magnitude 7.5 to 8.5 during this time and the flashes were about 2 magnitudes brighter than the object. Note periods of 3 minutes and 6 minutes in the above data. We were hampered by some clouds off-and-on from 05:05 to 05:45 and again from 06:15 to 06:35. I switched from a 50x eyepiece to a 90x eyepiece for the 8-inch during this time. The "action" started at 06:47. We saw three very similar operations. Each one started with symmetric fan-shaped plumes going north and south from the object. Then the plumes expanded into faint crescent-shaped "shells". These started at 06:47, 06:48:05, and 06:48:55. Then at 06:53:55, the Centaur orbit circularization burn started. This was a fan-shaped plume going back to the west. At 06:54:45, the burn ended and a "gap" became visible between the plume and the object. At 06:56 I estimated that the plume appeared to be about 5th magnitude in the 12x80 finder scope. At 06:56:30, the object brightened to magnitude 5 very briefly and another plume appeared to the west. This was a very short event and a gap between the plume and the object appeared almost immediately. At 06:59 I noted that this second plume was very faint, but Ed said he could still see the first plume in his binoculars. The object was moving away from the plumes. Probably a 1 degree gap between them after only 5 minutes. At 07:22:56, there was a single event very much like the original three events at 06:47. Two plumes were emitted north and south for a few seconds and they moved away from the object and formed two crescents and dissipated over the next 2 minutes. At 07:26, I believed I could see a second object "in front of" (east of) the brighter object. The two objects separated very slowly. At 07:30:25, the "main event" (Centaur fuel dump) started. A fan-shaped plume was emitted to the north. This gradually grew in size and brightness. At 07:37 it was estimated to be 0.2 degrees in diameter and magnitude 2.5. It was easily visible to our unaided eyes. At 07:39, the size was 0.3 degrees and there was a gap between the bright object and the plume, so the fuel dump had ended. The plume continued with the two objects. The fainter object remained at the "base" of the plume. The brighter object gradually moved away from the fainter object (moving to the south and east). I continued to obtain star passage timings for the two objects to allow me to determine orbits for each. By the time I stopped at 08:21, the two objects were about 0.3 degrees apart and the plume was only very faintly visible in the 8-inch about 0.3 degrees noth of the faint object. The bright object was about magnitude 9.0 and the faint object was about magnitude 10.0. I assume that the bright object was the Centaur and the faint object was the Milstar 5. Spacecom has assigned catalog numbers 27168 to the Milstar 5 and 27169 to the Centaur. Mike McCants Austin, TX ----------------------------------------------------------------- Unsubscribe from SeeSat-L by sending a message with 'unsubscribe' in the SUBJECT to SeeSat-L-request@lists.satellite.eu.org http://www.satellite.eu.org/seesat/seesatindex.html
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