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Old October 10th 04, 07:52 PM
Mr. 4X
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(Eugene Shubert) wrote in
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"Mr. 4X" wrote in message
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(Eugene Shubert) wrote in
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What is the darkest hour of the night?


That depends on a lot of things. There is almost no direct sunlight
2-3 hours after sunset,


Isn't there a measurable amount of sunlight that's scattered by the
atmosphere, reaching further into the night than a mere 2-3 hours of
earth rotation?


I think that scattering probably decreases as you get closer to the
Equator (same angular distance = more linear distance).

When a sizable part of the earth's surface and atmosphere is heated up
during the day, doesn't a measurable fraction of that heated material
reradiate energy in the visible spectrum?


NO.

Thermal radiation has no (or at least no significant) visible component
under 300 C or something like that.

To keep the calculations simple, let's ignore artificial lighting but
factor in the reflected light of the Moon if you know how to do that.

Eugene Shubert
http://www.everythingimportant.org