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Re: shortest twilight problem...
From: Marcel Tschudin
Date: 2010 Jun 29, 14:00 +0300
From: Marcel Tschudin
Date: 2010 Jun 29, 14:00 +0300
George, you wrote: > Yes, the length of twilight certainly does depend on latitude, but the > question was not about the length of twilight, but the DATE of the shortest > twilight. And that, as I see it does not depend on latitude. Does Marcel > agree? OK, George, yes I misunderstood your the statement. The coarse way how we look at it the (approximate) date is not expected to change with latitude, or at least not much. Since the problem has an Arab origin: Could it be that it was originally related to the prayer times? The duration of this twilight corresponds to the duration between evening and night prayer. One being done right after sunset and the other, depending on the understanding, when the sun is 17 to 19 deg below the horizon. Marcel
