I'm pretty sure the ISS was just a bit below the horizon as seen from Seattle. About 1 degree below the horizon. And in the same general direction as the sun. So I don't think it was the ISS. >across the horizon from NNW to SSW That part matches >with about a peak of 40deg inclination (at most) You mean altitude, right? We usually measure positions of satellites using alt/azi where azimuth is compass heading and azimuth is degree from horizon from 0 to 90 (but in this case ISS should have been -1 degree). If you mean it was 1 degree from the horizon then maybe you did see it. Whereas 40 degrees altitude would be very high - about half way between horizon and straight up. FYI, Inclination is an orbital term that refers to the tilt of the orbit and by definition is also the farthest latitude that the orbit passes over. So a satellite with an inclination of 40 degrees would never get straight overhead if you lived in seattle (latitude 47) but would still be visible to the south. So if it isn't the ISS then it's going to be hard to find. If I put even a 10 degree patch of sky into any satellite searching software with a 5 minute window I'm going to get a dozen satellites passing through that tiny piece of sky. But if you give me a broad swath of sky as you did there will be many thousands of matching satellites. Too many to look through. So no one is likely to reply to this email. Sorry! - George Roberts http://gr5.org -----Original Message----- From: Kevin Grey Sent: Tuesday, November 06, 2012 1:24 PM To: SeeSat-L@satobs.org Subject: Can someone ID this object for me? Hello, I was outside walking with a coworker last night. We saw what appeared to be an aircraft travelling across the horizon from NNW to SSW with about a peak of 40deg inclination (at most). It was just after sunset and there were some high altitude clouds (thin with big shadows, I believe) that did not appear to affect the magnitude of the object. Coworker thinks I am crazy for stating its likely ISS, as opposed to an airplane. I loaded up an ISS tracking app on my phone and sure enough, it showed ISS passing with a trajectory consistent with what we had observed but when I login to Heavens-Above, it does not list an ISS pass for my location at that time. I suspect that the only reason it was visible was because of its trajectory perpendicular to the setting Sun and my geographic location and that Heavens-Above may exclude passes below a certain inclination. Can someone identify this object for me? Date/Time of End of Pass: 11/05/2012 17:32 Pacific Time == 11/06/2012 01:32 UTC Location: 47.644704, -122.139079 Object trajectory: Travelled from NNW to SSW with peak inclination of 40 degrees (probably lower) ~~K -------------- next part -------------- An HTML attachment was scrubbed... URL: http://mailman.satobs.org/mailman/private/seesat-l/attachments/20121106/803d8715/attachment.html _______________________________________________ Seesat-l mailing list http://mailman.satobs.org/mailman/listinfo/seesat-l _______________________________________________ Seesat-l mailing list http://mailman.satobs.org/mailman/listinfo/seesat-l
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