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![]() Current plans are for Soyuz TMA-9 to be launched on Sep 13 at 20:44 gmt, and land ten days later. These dates, and the recently-added Iranian-American space tourist Anousheh Ansari, raise an interesting question about the Islamic calendar. Currently, the first day of Ramadan this year is expected to be September 24, following a sighting the previous evening of the crescent new moon by observant Moslems. But it's possible that Ansari's unique position in space may allow her to spot the crescent a day earlier, and if she reports it credibly, the entire Moslem world may have to start Ramadan a day earlier than expected. According to http://aa.usno.navy.mil/faq/docs/islamic.html, "The sighting of the lunar crescent within one day of New Moon is usually difficult. The crescent at this time is quite thin, has a low surface brightness, and can easily be lost in the twilight." Actual new moon date is September 22 at 11:45 GMT, which is in the middle of the last-but-one crew workday. But it would be many hours before anyone could expect to visually observe the growing crescent. Could Ansari see it before having to return to Earth the next day? USNO: "The record for an early sighting of a lunar crescent, with a telescope, is 12.1 hours after New Moon; for naked-eye sightings, the record is 15.5 hours from New Moon. These are exceptional observations... " BUT they have to vie with terrestrial twilight, which space-based observations don't. It thus seems physically possible for an orbiting observer to detect the new moon 12 hours after the precise moment, and quite possibly a few hours sooner. Twelve hours after new moon, the crescent is about 6 degrees from the sun, and from a satellite, would set about a minute and a half after the sun -- when the western atmospheric limb is sufficiently dark for the crescent to be seen against a black sky. That would be the middle of Ansari's last sleep period in space -- and possibly an event worth skipping sleep over. See also http://webpages.charter.net/darksky2...s/May2000.html |
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