Hi, I was observing in the region of the geostationary belt on July 5, 2000 at 5:36 UT when I picked up Brasilsat B3 (98006A, 25152). It was unusually bright, between 7.5 and 8th magnitude. As a quick check, I was able to see it my 10 x 40 binoculars. M11 made a handy reference for the position. I had observed Brasilsat B1 and B2 earlier the same night and bother were the more normal 12th magnitude or so. I believe all three are HS376W spin stabilized spacecraft. I suspect I understand the brightness of B3 but maybe one of the geometry gurus (Rob?) can do the calculations more carefully than I can. The position of the satellite was RA 18hr 51min DEC -6 deg 47' and the sun was at RA 6hr 59 min DEC 22deg 45'. This puts them almost exactly 180 degrees apart in RA. Putting it another way, the satellite was at AZ 188 EL 39 degrees and the time was about half an hour after solar midnight so the sun was at about AZ 8 -18 EL degrees. All of this puts me close to the Sun-Satellite line and about 20 degrees below it and I suspect all I saw was a favourable set of reflections off the solar cells on the cylindrical satellite. I have occasionally seen other geosats appear brighter that others but this was much more obvious. Any other ideas on the cause? Is there something unusual about this object? I tried to find it last night to see if the brightness is strongly time dependant but the clouds did not cooperate and I could not see it at all. BKH Brian K. Hunter, Department of Chemistry Professor Queen's University bkh@chem.queensu.ca Kingston, Ontario (613)-533-2620 Canada K7L 3N6 44 14' N 76 30' W ----------------------------------------------------------------- Unsubscribe from SeeSat-L by sending a message with 'unsubscribe' in the SUBJECT to SeeSat-L-request@lists.satellite.eu.org http://www2.satellite.eu.org/seesat/seesatindex.html
This archive was generated by hypermail 2b29 : Thu Jul 06 2000 - 12:11:36 PDT