> My watch alarm went off and I started to count > up. 1, 2, 3, 4, 5, 6, 7, 8, ..............10, 11 and on up to 30. The > station was supposed to cross at 8 seconds past the minute! We saw nothing. > :~( I suppose the sun's intensity overwhelmed the tiny silhouette and the > clouds ruined enough of the clarity that we didn't have a chance. It was > only going to be visible for about a second. Depending upon the angle above the horizon (i.e., the distance to the space station) it can take as little as .4 seconds to cross the face of the sun or moon. Also, being as little as 1 mile off the transit track can be the difference between seeing a dead-center transit, or nothing at all. The space station's silhouette wouldn't necessarily be so small- if the ISS is ever completed, it should be about the same angular size as Jupiter, when passing directly overhead (i.e., about 2% the angular size of the sun & moon). Finally, it's possible that the program's prediction was wrong, as extreme accuracy is obviously required. Accurately predicting a transit for the setting/rising sun/moon might be especially difficult, since at that low angle, the observation location may even have a significant dependency upon the local air temperature, which affects the amount of atmospheric refraction. > Has anybody successfully seen the ISS cross the sun's disk? Has anybody ever > taken a video of it? It was 2:05 PM my time. I've seen the ISS pass across the face of the moon, and have a pretty piss-poor picture to prove it: http://iss-transit.sourceforge.net ----------------------------------------------------------------- To unsubscribe from SeeSat-L, send a message with 'unsubscribe' in the SUBJECT to SeeSat-L-request@satobs.org List archived at http://www.satobs.org/seesat/seesatindex.html
This archive was generated by hypermail 2b29 : Wed Feb 26 2003 - 18:36:51 EST