Amateur astronomer Ali Rasoulzadeh of Ardabil, Iran, spotted the re-entry fireball of 2014-064C / 40279 on Jun 17 near 18:50 UTC. He published a brief cell phone video and his sighting report on You Tube: https://www.youtube.com/watch?v=URjIthj86jI The video is dark, but with brightness boosted the re-entry fireball is clearly evident. The left to right motion is as expected for this object from the reported location (38.4866 N, 47.7348 E, 1157 m). Mr. Rasoulzadeh responded to requests for additional information, via You Tube and the Reentrywatch mailing list. His reported local time of the event, 23:20 (UTC+4.5h), was as recorded by the cell phone camera. He stated that the video was shot near the mid-point of the sighting, which is consistent with the slightly descending angle of the trajectory on the video, indicating that it was shot soon after culmination. I asked him to return to the location of the sighting and attempt to recall the track relative celestial objects. He did so about one week after the sighting, and provided a star chart with his sketch of the trajectory, with the following comments: "I returned to sighting location and checked out the sky to remember the pass... It was above Leo and below Ursa Major (I'm confident) and then continued towards cassiopeia and vanished above it." This proves to be reasonably consistent with the orbital plane, time and location of sighting, and altitude well below 100 km. The final USSTRATCOM TLE appears to be that of epoch 15168.60345914 and mean motion 14.384 rev/d. Another was issued for the identical epoch, with n0=13.9 rev/d, but the other one closely matches the perigee and apogee heights in the satellite catalogue, so appears to be the final estimate. I propagated the final USAF TLE using the numerical integrator in GMAT (General Mission Analysis Tool). By trial and error I found the ballistic coefficient that caused the pass to occur close to the reported time. This analysis yielded descent to 10 km altitude at 18:56:25 UTC, and the following sub-orbital TLE at the time of the sighting (computed from a Cartesian state-vector): -37 X 94 km 1 40279U 14064C 15168.78438819 .00000000 00000-0 00000-0 0 87 2 40279 48.5999 189.4910 0102166 196.9399 219.6045 16.93370870 03 This TLE is in reasonable agreement with Mr. Rasoulzadeh's description and sketch of the track. The only significant disagreement is in the relationship with constellation Leo. Mr. Rasoulzadeh recalled that it passed above Leo, but it must have passed closer to the centre of Leo. It did pass below the outer two stars of the bowl of the Big Dipper, as sketched, and it did pass close to Cassiopeia before passing below the horizon, as recalled by Mr. Rasoulzadeh. He did well to recall the trajectory as accurately as he did. The estimated altitude at the time of the sighting is 80 km, which is within the range where most objects break up, consistent with the video. We have heard of a sighting from Mosul, Iraq, which was within range of the final descent, but are awaiting corroborating details. I have added this re-entry to the table of sightings that I maintain: http://satobs.org/reentry/Visually_Observed_Natural_Re-entries_latest_draft.pdf Ted Molczan _______________________________________________ Seesat-l mailing list http://mailman.satobs.org/mailman/listinfo/seesat-lReceived on Sat Jun 27 2015 - 12:39:45 UTC
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