----- Original Message ----- From: "Matson, Robert" <ROBERT.D.MATSON@saic.com> To: <b_gimle@algonet.se>; <rdcrisp@earthlink.net> Cc: <bjorn.gimle@tietoenator.com>; "'Seesat-L'" <SeeSat-L@satobs.org> Sent: Wednesday, March 16, 2005 2:49 PM Subject: Richard's mystery GEO satellite near Cone Nebula >> Though Rob is an expert I tend to disagree. > > Bjorn is being kind here -- I'm definitely out of practice! ;-) > >> My image shows the track of 76-4A inclined 3.9 degrees to the >> declination grid (+10 runs just below the glint) The scale >> of UNID_314.gif overlaid on iridium_flare_xga_ov.gif is 1.96 >> degrees (118') over the 805 pixel vertical. > > I didn't bother to rotate images and do a slope comparison since > I thought the match looked reasonably close in time, location and > slope. However, now that I've done so I see that Bjorn is right -- > the inclination is off by a couple degrees. While this doesn't > seem like a lot, it is enough to rule out 76-4A as a match. > > Symphonie 2 was on a parallel track, so it's not a good > match for the same reasons. > > Ekran 8 and OPS 9442 were closer to the correct location in > cross track (and on more nearly east-west trajectories), but > their intrack positions are poor and the slopes are actually > too far the other way (too horizontal). > > Nearby Kiku 2 (ETS 2) looks to be close to the correct slope, but > shifted well to the east. Bottom line is that none of these > is a solid match. > > Two possibilities to consider: > > Are the observer coordinates correct and/or can they be provided > to greater accuracy? I live in Castro Valley, California. I imaged from my backyard. > > Are the reported UTC date and time absolutely certain? Certain on the day. The time is a function of the timestamp from my laptop. The clock is reasonably close to correct. I am not sure if the timestamp on the FITs file is at the beginning or end of the exposure but I can do an experiment to nail that down. > > Finally, answering Richard's questions: > > "So Bjorn, you say it is 76-4A? And Rob, you say it is #8585 right?" > > No, #8585 is the same as 76-4A. Bjorn didn't identify an alternate > candidate (nor can I). It remains an unknown unless the location, date > or time were in error. > >> We are all pretty sure it is a LEO because of the EW travel, right? > > No -- I'm very confident that it is a *GEO* because of the EW travel. > Could be a glint from a small piece of debris near GEO that isn't in > the catalog. By measuring the RA/Dec of two positions in the track > and assuming a GEO orbit, I bet Ted Molczan could generate you a > search orbit. But you'd need to reacquire it soon in order not to > lose it. If successful, it might very well be the dimmest object > ever discovered by an amateur! --Rob Well that is pretty cool. I wasn't looking to have any records etc. I just thought I had observed an Iridium flash. I can certainly pin down my Lat Long more accurately. I can also pin down the limits to my time of day capture etc. I want to thank you guys for all the help. Really do want to thank you. I'll chase down this information and let you know. rdc > > ------------------------------------------------------------------------- > Subscribe/Unsubscribe info, Frequently Asked Questions, SeeSat-L archive: > http://www.satobs.org/seesat/seesatindex.html > > ------------------------------------------------------------------------- Subscribe/Unsubscribe info, Frequently Asked Questions, SeeSat-L archive: http://www.satobs.org/seesat/seesatindex.html
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