A week of observations from a single site is not enough to determine the rotation axis, unless the mass distribution of the satellite, and orientation of the panels, is known. Observations from widely differing latitudes, and/or months of observations, and/or finding the "other part of its orbit" would help. Assuming that the panel normals point 90 degrees from the spin axis (very common) I find an approximate axis near RA 23:25 Dec.-13. This is an (unusual) situation like Superbird-A so the flashes run almost perpendicular to the track, and the RA of observed flashes is nearly independent of observer location. Unfortunately, "the other part of its orbit" in this case is just where the Sun is. It also resembles Superbird-A in that it has a phase shift in the (short) visibility period. Noting the time (better:position) where the flashes are of equal brightness (or the mid-position of visibility of 27 s interval flashes) would make computation of axis more accurate. For 60N on Jan.21 I find flashes at RA 2:18 to 2:26 Dec. -1.5 (22:25-22:33 UTC at 18E). For 34S RA 1:58 to 2:06 Dec.+10 (22:16-22:24 UTC at 18E) PS: Rob, and SkyMap users, I noticed in my 'StarName.txt' that I have two 'zet Ari' 'zet Ari','', 3.248333, 21.04444, 4.89 'zet Ari','', 3.263861, -8.81972, 4.80 The 2nd one should be in Eri ! /Björn >Från: mike.waterman@web-hq.com ... >Flashes are actually 2 sets; each set has period (050118) 54.04s. >The two sets overlap for about 4 minutes, during this 4 minutes >the flashes come at intervals of 54.04/2 = 27.02 s. >The RA of the last flash has not changed much in 6 days, probably the >RA of the first flash has not changed. There must be another part of >its orbit where flashes can be seen, but noone knows where. ------------------------------------------------------------------------- Subscribe/Unsubscribe info, Frequently Asked Questions, SeeSat-L archive: http://www.satobs.org/seesat/seesatindex.html
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