Despite promising forecasts, I have not yet been able to look for the 58-degree NRO satellite yet. There should still be passes above 20 degrees for over a week. I have made several fruitless attempts to see USA 186 using 06267 elset +- 6 min. Only yesterday I realized that the small diff in MM from USA 161 was a false reassurement. The small diff also in NDOT2 means that MM has changed less, when the accumulated time separation (from USA 161) has increased 25 minutes (historical value from previous KH pairs) from the minimum (when periods are equal). I find a long-term NDOT2 average for USA 186 is .000100. For USA 161, it has been .000042 since about day 06080, but .000033 since 06130 and even less late 2005. Using .000100- .00042, it takes 66 days (sqrt(25/98/(.00100-.00042)). The MM diff at the time of maneuvre would be 2*66*(.00100-.00042) = .0077. But the actual date of equal MM is in June (?), when ndot2 were very close - more than 66 days before the latest elset 06267. Extrapolating instead from MM diff of day 06267, I get the time of maneuvre as day 0287, and the new MM=14.75343. I suggest the following search elsets, which I tried in the interval -10/+11 min today (first day in months without fog in the low N), with Envisat Ariane as only find :-( USA 186 -15 1 28888U 05042A 06287.74635683 .00010000 00000-0 99910-4 0 28 2 28888 97.9408 348.1927 0539998 99.3930 266.8723 14.75343000 2961 USA 186 06287 1 28888U 05042A 06287.75635698 .00010000 00000-0 99910-4 0 25 2 28888 97.9408 348.1927 0540000 99.3317 266.9344 14.75343000 2966 USA 186 +15 1 28888U 05042A 06287.76635695 .00010000 00000-0 99910-4 0 23 2 28888 97.9408 348.1927 0540000 99.3480 266.9179 14.75343000 2963 Using numerical integration of (sparsely interpolated) MM differences my maneuvre date becomes 06273, with MM=14.754 (+.00628) and approximate elset: USA 186 06273 1023 x 265 1 28888U 05042A 6273.45950294 .00010000 00000-0 99910-4 0 18 2 28888 97.9408 334.0488 0539536 145.6850 218.0490 14.75400000 840 which gives a prediction only a few minutes ahead of USA 186 06287 /Björn at 5919 ------------------------------------------------------------------------- Subscribe/Unsubscribe info, Frequently Asked Questions, SeeSat-L archive: http://www.satobs.org/seesat/seesatindex.html
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