82041C has entered morning visibility in the N. Hemisphere. The latest elements are 158 d old, so a search will required in order to resume regular tracking. I intend to try to recover it in the coming days, but in case anyone else would like to try, I offer the following suggestions. I have produced the following search elements by reducing the rate of decay of Mike McCants' latest elset, to reflect the decreased solar activity of the past 158 d: KH 9-17 ELINT 0.3 0.9 0.0 6.5 v 1 70000U 02066.79004738 .00003875 00000-0 54519-3 0 02 2 70000 95.9590 83.3641 0003000 343.3469 16.6530 14.77431534 06 I estimated the decrease by analogy with 84065C, a similar payload, in a slightly lower orbit. I found that over about the same period, I had to reduce 84065C's rate of decay by 35.4 percent in order to accurately predict its recent passes, so I reduced 82041C's rate of decay by the same percentage. I have used this method successfully in the past, but I caution that a generous allowance still is required for prediction time uncertainty. I suggest starting the first search 10 min early, and being prepared to wait at least as long late. This object flashes about once per second, and its minima may be invisible at high phase angle. Less allowance is required for Earth's rotation during the search period, by observing at moderately low elevations, as long as the object is likely to be sufficiently illuminated. Ideally, select a portion of the sky with a nice fence of stars perpendicular to the predicted path, to provide maximum opportunity to obtain an accurate position. For the recovery, even a rough position, i.e. "passed 1 deg below Altair" timed to within a few seconds, would be very helpful. That would enable the search orbit to be improved sufficiently to easily re-acquire the object, to obtain precise positions. Ted Molczan ----------------------------------------------------------------- Unsubscribe from SeeSat-L by sending a message with 'unsubscribe' in the SUBJECT to SeeSat-L-request@lists.satellite.eu.org http://www.satellite.eu.org/seesat/seesatindex.html
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