David Anderman said: >Perhaps I am missing something, but this object is basically in a sun >synchronous orbit, so it is going to appear at the same local time on >every pass. Yes, but if you look at several nights' worth of predictions, you'll see that as time progresses, the sat passes over you (Art - winter viewing location in Lewisburg WV) slightly earlier each night, "shortening" the vertical extent of the shadow. So the satellite passes into sunlight higher above you, earlier than the last night. Eventually, this reaches a peak best case, which at your latitude seems to be about 80 deg altitude. Then (wouldn't you know it) the passes are too early. So then the sat emerges from shadow even more south than before, twilight is too strong to see it. This is very typical of sun-synchronous orbits in (northern) summer. Then there may be a very short optimum window in fall or spring when the earth's shadow is "tipped" enough to see the satellite well, until winter when it will probably be very difficult or impossible to see because the shadow. Brad Young TULSA 1 COSPAR 8336 36.1397N, 95.9838W, 205m ASL ------------------------------------------------------------------------- Subscribe/Unsubscribe info, Frequently Asked Questions, SeeSat-L archive: http://www.satobs.org/seesat/seesatindex.html
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