I was asked to post an update for the possible visibility of the ISS during the total eclipse of the sun on 29-MAR-06 for southern Turkey as some folks out there want to spare a few of their precious eclipse seconds looking out for the ISS. The following is for the place where the center line hits the coast (Side) which is where many eclipse watcher will congregate. The weather outlook seems to be good so it might actually work (has anybody ever observed an artificial satellite while watching a total eclipse at the same time?). Given is the time in UT, (Azimuth, Elevation) and an estimate of magnitude. 10:54:30 (310,34) mag -0.4 10:55:00 (309,52) mag 0 10:55:15 (307,66) mag 0.5 10:55:30 (296,83) mag 1.2 10:55:45 (141,79) mag 1.8 10:56:00 (135,62) mag 1.4 10:56:30 (133,40) mag 0.6 10:57:00 (133,27) mag 0.3 10:57:30 (132,19) mag 0.2 I tried to factor in the degree of eclipse as viewed from the ISS and also the illumination of the ISS by the non-umbral parts of the Earth so the given magnitudes are certainly up for debate - I don't claim them to be perfect! Hopefully we get some reports about it. My guess is that the actual contrast doesn't vary too much because when the ISS is brighter it will also be in a brighter part of the sky and when it is darkest (the greatest eclipse as seen by the ISS is around 10:55:40 UT) it happens to be in the relatively darkest part of the sky. The situation is somewhat similar for the whole coastal stretch between Antalya and Alanya although Antalya seems to have a slight egde as totality there starts about 30 sec earlier. Further to the North or South the ISS arrives too early or too late with regard to the umbra on the ground. I don't think you would have any realistic chance to see it there. Between 10:48 UT and 10:55 UT a transit of the ISS in front of the partially eclipsed sun can be seen along a line from Liverpool via Cologne to Istanbul but most people who would normally care about something like that seem to have travelled down into the path of totality (I'm one of the few left behind so it seems!) Even though the ISS does not make it into totality (too bad they skipped the maneuver two weeks ago!) the crew (or maybe a remotely controlled external camera) might still be able to briefly glimpse the corona if the part of the sun still illuminated happens to be blocked by some external structure (like the solar panels). As there is no light scattering atmosphere up there to interfere this would be an impromptu coronograph. Gerhard HOLTKAMP Darmstadt, Germany ------------------------------------------------------------------------- Subscribe/Unsubscribe info, Frequently Asked Questions, SeeSat-L archive: http://www.satobs.org/seesat/seesatindex.html
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