I noticed that the inttles "+MA" elset predicts tonight's pass for me (19:51 UT) 4.7 minutes earlier than my suggested "7 AOP". Also that "+MA" has 50% higher drag than the original old TLE, which I began to suspect. This probably means that it has completed seven more orbits than that elset predicted, ie almost a full day in error after 163 days. But the "+MA" still predicts a pass (at 42 deg alt in the SE for me) 2 degrees higher than "7 AOP", like yesterday. So I recommend "+MA" until new obs arrive. I may still have clear skies ! /Björn ----------------------------------------- 2016-09-11 18:58 GMT+02:00 Björn Gimle <bjorn.gimle_at_gmail.com>: > Last night I found USA 179 r after a partial track scan. It was only 16 > min early on the classfd 163 days old, yet after adjusting B* to fix the > time offset, it still predicted it 4 degrees above the obs at 42 deg alt in > the SSE. > With inttles the figures were 13 min and 3 degrees. > Actually, the drag effect could make for several orbits in error- > increasing from 0.1 orbit to 1.1 orbit requires only a 7% drag increase. > I also changed AOP+MA to get the track closer to my obs, it might be more > helpful for a few days. > But this TLE shows a discrepancy in the track angle. > > I'm at a loss as to which elements to adjust - more obs are needed. > > USA 179 r +7 AOP > 1 28385U 04034B 16091.25392007 0.00052500 00000-0 10019-2 0 00 > 2 28385 57.3390 119.7392 3808439 262.3433 232.2776 7.88880991 03 > USA 179 Rk +MA > 1 28385U 04034B 16254.46759977 0.00083586 00000-0 15065-2 0 00 > 2 28385 57.3489 276.6181 3697518 341.0707 33.7470 8.10254303 1633 > > IOD: > 28385 04 034B 5919 G 20160910201034500 18 25 2210700+140900 55 R > 28385 04 034B 5919 G 20160910201054500 18 25 2219900+160600 55 R > > -------------------------------------------------------- > Björn Gimle, COSPAR 5919 > 59.2617 N, 18.6169 E, 51 m > Satellite observation formats described: > http://www.satobs.org/position/IODformat.html > --------------------------------------------------------- > _______________________________________________ Seesat-l mailing list http://mailman.satobs.org/mailman/listinfo/seesat-lReceived on Sun Sep 11 2016 - 13:44:04 UTC
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