("Astrometry.net" JPG link : http://nova.astrometry.net/image/5749384) And the HeavenSat prediction of the tracks at the approximate time may end up in the files folder ? On the morning Jan.12 I had a favourable pass of the last 10 Iridiums, 14.5 h after launch. Because they were still far below nominal height, the evening passes were in shadow at my latitude. I copied all of the morning's images around 83 degrees in the E onto my hard disk ( 2s at f/2.0, ISO 800, due to the morning twilight, roughly every 10s ), and opened the image closest in time to the predicted time for the new Iridiums. To my surprise, THIS one contained (all 10 ?) satellites. It may look like one track of one flashing satellite, but I have the next image, showing most part of the same trail, shifted by less than half the length in that 8s interval. All 10 !? That is what my prediction showed - it seems most pairs are too close to be recognized separately as 2s long tracks - the total span is about 11 s wide. I should have used 1s (and maybe ISO 1600) exposure to separate several objects. The B object (and D) has an elset epoch 5+ h after my obs, and shows B 5 s late relative to an elset at 4+ h - being raised ?? (This earlier elset, and the remaining objects, do not have an epoch close to the ascending node time) And the duration of the trail would be 16 s with these TLEs. -------------------------------------------------------- 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 Jan 13 2019 - 11:02:32 UTC
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