>I just tried to look up information about what iridium flares would be >visible for the next 7 days as seen from the south pole. I get none. Can >someone else try H-A and see if they get anything? I may have done something >wrong. Fascinated by the subject I did some South Pole Iridium Flare calculations with my own program. The special geometry between an observer at the South Pole, the direction of the Sun and the Iridium orbital planes which changes only gradually during one day leads to certain days experiencing flares all the time with no-flare days in between. On APR 15/16, APR 29/30, MAY 10 and MAY 14/15 (2005) you can experience mag -8 monster flares every 9 minutes all day long. A particular satellite which has flared will apear once again after one orbit 1h40min later in almost the same relative position and cause another flare. The flare position in the sky (with regard to the background stars) stays the same (which means it will rotate in azimuth around the sky during the day). After about a day the geometry has shifted a little and the flares get weaker, then disappear before a few days later another orbital plane and antenna-Sun geometry will cause another series of flares. The whole thing really works because on the South Pole the elevation of the Sun stays essentially constant all day long. Gerhard HOLTKAMP, Darmstadt, Germany ------------------------------------------------------------------------- Subscribe/Unsubscribe info, Frequently Asked Questions, SeeSat-L archive: http://www.satobs.org/seesat/seesatindex.html
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