It seems Dan's images are produced relative to Earth-Fixed (rotating) coordinates, so the tracks shift about 25 degrees west during an orbit. I used AllCola, and then SkyMap in Polar (siderial) coordinates. I ran the "initial" elsets of the DMSP 5D-2 F11 91-082 debris through "AllCOLA". I had a large range limit, but sorted them on range, then those under 10 km on date and time. It listed 34 encounters 04/11, 18 on 04/12, 42 on 04/13, 98 on 04/14, 604(!) on 04/15, 110 on 04/16, 64 on 04/17, 72 on 04/18, 10 on 04/19, 14 on 04/20, 30 on 04/21, 12 on 04/22. Obviously, the defragmentation occurred on the 15th April 2004. Some spread is due to age and inaccuracy of elsets, some because the mean motions were spread between 13.84 (82BJ) and 14.49 (82AD), so encounters happened every 37 hours. (Inclinations are 98.23 [S] to 99.01 [AD]) On 04/15, the encounters over 1.5 h intervals were 22 22 16 16 20 24 40 42 48 172(!) 42 50 18 22 22 32 Close encounters with the satellite itself during peak hours were: 12:20 12:40 12:48 12:53 12:59 13:38(2) 13:39 14:00 14:24 14:28(2) 14:36 14:41 14:55 14:56 14:57 14:58 15:04 15:13 16:12 17:08 17:43. Based on the orbit count of the TLE, fragments F-L were tracked late on Apr.15 At 14:54, 32 debris objects where within +-4 degrees of orbital longitude from the satellite. Best clustering of the orbits appears to have been around 64E (on that orbit), 10N. Graphing the orbital height vs. latitude for the ascending and descending halves of the orbit at that time confirms this. Excluding the six most differing orbits, the remainder are 815-841 km at latitude 9S (ascending). On the other half, I get 798-997 km. My charts are about 60k in .gif or .jpg, so I can't put them on DSat. ------------------------------------------------------------------------- Subscribe/Unsubscribe info, Frequently Asked Questions, SeeSat-L archive: http://www.satobs.org/seesat/seesatindex.html
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