I detected errors in my computations, and some misconceptions in other replies: I used "tropical" instead of siderial rate of stars, so the value 0.991(twice) in my .CSV data should be replaced by 0.989 I swapped the declinations of the "fake" observations produced, so the corrected obs should be 2004-12-19 20:50 04:29:03 -7.390 2004-12-19 20:54 04:32:57 -7.650 (and FOV becomes 0.510 x 0.383) New elset produced by FIRST.EXE still needed some RAAN adjustment to bring it closer to Astra: 04-854A 4.0 1 94854U 04854A 04354.37075419 .00001200 00000-0 24000-3 0 00002 2 94854 013.5131 244.6514 0000010 000.0000 000.0000 01.00750200 00000 This mail was (is) sent via webb, and HTML removes duplicate blanks, so you must edit the elset before using it. The fact that it appears to move along an RA great circle in the alt/az reference frame does NOT imply that it is in high-i orbit! Since the southward motion is just 26% of the eastward motion (in the Earth-fixed reference frame) inclination should be near the TLE above. I have not been able to identify the five or so stars in the 20:48:39 frame, or the one traversing 20:49:00-20:50:23 (...?) or the brighter one 20:53:09, so my positions are from the predicted pos of Astra. The fact that FindSat lists Astra 3A for BOTH my positions is a deficiency of ANY program trying to evaluate a single position in each run. To make a match, the time and crosstrack errors should have similar value (including sign/direction) for all points used. I prefer to enter the coordinates into SkyMap's DEEPSKY.TXT file, and match the tracks that run parallell to the points, at the right speed. ----- Original Message ----- > UNID;;RA;Dec > 2004-12-19 20:50;;04:29:02;-7.651;;;1280;;;;;0.512 > 2004-12-19 20:54;;04:32:58;-7.389;;;960;;;;;0.384 > >04-854A 3.0 >1 99854U 04854 A 04354.86927254 .00000000 00000-0 00000-0 0 00 >2 99854 13.9728 245.0669 0000010 0.0000 0.0000 1.01644026 00 > ------------------------------------------------------------------------- Subscribe/Unsubscribe info, Frequently Asked Questions, SeeSat-L archive: http://www.satobs.org/seesat/seesatindex.html
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