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Re: Converting a Lunar Distance to GMT
From: Dan Allen
Date: 2003 May 5, 19:59 -0700
From: Dan Allen
Date: 2003 May 5, 19:59 -0700
On Monday, May 5, 2003, at 07:39 PM, Bruce Stark wrote:
> Here is the equation. Since I don't know how else to indicate it in
> this
> e-mail program, the phrase "sq. root of" will have to stand in for the
> radical sign.
>
> hav D = sq. root of {hav [d - (m ~ s)] * hav [d + (m ~ s)]} * [(cos M
> * cos S
> )/(cos m * cos s)] + hav (M ~ S)
Often sqrt( ) is used, just as it is written in many programming
languages.
Two questions arise:
1) in today's posting of May 5th, what are the quantities D, d, m, s,
M, and S supposed to refer to?
2) in your posting of Apr 28th, what are the actual equations for the
oblique spherical triangles that you refer to? Are you referring to
the law of cosines for spherical triangles or to something else?
I am still looking for a concise, fully self-contained algorithm for
doing a lunar. We're getting closer!
Thanks again Bruce,
Dan
