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Re: Beginner moonrise and set question
From: Bill B
Date: 2004 Sep 23, 02:42 -0500
From: Bill B
Date: 2004 Sep 23, 02:42 -0500
> Actually, 24h rotation of earth is also slightly MORE than 360 deg arising > from the earths orbit around the sun Relative to what? Agreed the Earth has to over-rotate relative to the stars for the Sun to be close to the meridian passage at noon (or any other reference point). If it rotated 360 d relative to the stars approx. 182.5 days through the cycle noon would be dark--AKA midnight. > Don't have the numbers handy .. but 23h 56m and odd seconds sounds about right Being a non-hard scientist, I've tried to derive that figure from a multitude of sources. It is a lot more consistent than a woman, but seems to float a bit if I do the math. Closer to the point: A sidereal day goes by in 23:56:something. A solar day in approx. 24:00:00 plus/minus eq, time. So I don't think I can apply almanac arc-to-time to stars. Too the point, given the odd (compared to solar/sidereal time) motion of the moon, can I apply the 15d = 1 hr (solar) arc-to-time to determine moonset at my longitude? Thanks Bill
