On the night of Jan. 20/21, 2006, a little after 0 hours UT, Peter Birtwhistle (Great Shefford Observatiory, UK) observed an unknown object for about 90 minutes. He then ran Bill Gray's FindOrb program with these observations to determine the orbit and found that the object was in an eccentric orbit with an inclination of 26 degrees and an orbital period of about 10.5 hours (mean motion 2.28 revs/day). He subsequently observed this object the following evening (Jan. 21 about 19 hours UT). (The above information was forwarded to me by Tony Beresford.) His observations determine the orbit to be: Unknown 060121 1 99001U 06521A 06021.66230520 .00000000 00000-0 00000-0 0 09 2 99001 25.7544 309.7110 7206807 334.1402 25.4852 2.28275302 03 The perigee is over 400 Km, so I do not believe that the drag term will be significant. Highfly predictions for the times of his observations: *** 2006 Jan 21 Sat morning *** Times are UT *** MAG HRS MIN ALT AZI HGT RANGE R A DEC 12.0 0 20 39 195 21495 22785 7 27.8 1.1 (miles) 12.0 0 40 37 198 20995 22376 7 37.2 -.4 12.0 1 0 35 201 20338 21821 7 46.9 -2.0 12.0 1 20 32 203 19518 21114 7 57.3 -3.8 11.9 1 40 30 205 18525 20245 8 8.4 -5.8 11.9 1 50 29 206 17960 19747 8 14.4 -6.9 *** 2006 Jan 21 Sat evening *** Times are UT *** MAG HRS MIN ALT AZI HGT RANGE R A DEC 12.2 19 10 28 114 21072 22905 6 44.5 8.3 12.2 19 15 29 115 21206 23032 6 47.0 8.1 He reported a (CCD) magnitude of 12. The above magnitudes used Highfly intrinsic magnitude 4. Normally a Centaur would have a visual intrinsic magnitude of about 2 or 3. So it is possible that the object could be brighter than these predictions when seen visually. Mike McCants ------------------------------------------------------------------------- Subscribe/Unsubscribe info, Frequently Asked Questions, SeeSat-L archive: http://www.satobs.org/seesat/seesatindex.html
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