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Re: Converting a Lunar Distance to GMT


Subject: Re: Converting a Lunar Distance to GMT
From: Bruce Stark (Stark4677@XXX.XXX)
Date: Mon May 05 2003 - 23:45:44 EDT


Dan,

Your question #1: Lower case m, s, and d refer to the apparent altitudes and
apparent distance. That is, corrected for everything but refraction and
parallax. Upper case M, S, and D refer to the true altitudes and distance.

Question # 2: If you are calculating electronically, stick with the law of
cosines for spherical triangles. But if you are using logs that's no good
either in terms of reliable accuracy or convenience. Get your equations out
of a pre-1950 Bowditch or an old spherical trig text book.

I'm somewhat behind the times, and am just coming to understand what the term
"algorithm" means. So don't expect me to be much help in developing a
self-contained one. I'd rather leave the electronic approach to others. But
I'll try to be at least some help when I can. Thanks for the advice on
sqrt(). I'll use it next time.

Bruce





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