Ed Cannon posted: >Last night looking for Gorizont 29, I saw an unid flashing >geosynch. The brightest maxima were +4.5. The flash >period was about 42 or a multiple of that. Based on positional observations from Sept. 20 04:43 to 05:52 UT I have derived the following circular orbit: Unknown 040920 1 90022U 04764A 04264.19896990 0.00000000 00000-0 00000-0 0 04 2 90022 9.7600 77.0000 0001000 223.0000 0.0000 1.06382000 09 This is quite low for a circular graveyard orbit. Alternatives are that the object was near perigee with a non-zero eccentricity: 1 90022U 04764A 04264.19898147 0.00000000 00000-0 00000-0 0 00 2 90022 9.7900 77.0000 0100000 223.0000 0.0000 1.04182000 08 1 90022U 04764A 04264.19894675 0.00000000 00000-0 00000-0 0 02 2 90022 9.8100 77.0000 0150000 223.0000 0.0000 1.02982000 02 1 90022U 04764A 04264.19899305 0.00000000 00000-0 00000-0 0 07 2 90022 9.8300 77.0000 0200000 223.0000 0.0000 1.01982000 09 There are many other solutions with appropriate values of eccentricity, argument of perigee, and mean motion. I can even generate a synchronous orbit with a high enough eccentricity: 1 90022U 04764A 04264.19903934 0.00000000 00000-0 00000-0 0 01 2 90022 9.8400 77.0000 0290000 223.0000 0.0000 1.00270000 08 But I am puzzled by an inclination of 10 degrees with a node at 77 degrees. I cannot generate an elset like this using any reasonable starting elset by applying lunar and solar perturbations. A typical orbit with a 10 degree inclination has its node about 43 degrees. A typical orbit with a node near 77 degrees has an inclination of only 5 degrees. Because of the place in the orbit where the observations were made, the inclination and node are reasonably accurate. The brightest flashes last night were about RA 19Hr 15Mn, Dec -12 degrees. The observed pattern was 3 bright flashes over 85 seconds followed by a gap when 4 flashes were not seen, followed by another 3 bright flashes about 210 seconds after the preceding set. Later, only flashes to magnitude 9 or 10 were seen in the 8 inch. Mike McCants Austin, TX ------------------------------------------------------------------------- Subscribe/Unsubscribe info, Frequently Asked Questions, SeeSat-L archive: http://www.satobs.org/seesat/seesatindex.html
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