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    Question re. A and B factors (corner cosines) lunars
    From: Magnus Sjoquist
    Date: 2012 Jan 23, 09:31 -0800

    Hi –
    Can anyone help me out on flwg question:
    One document on the list, “Lunars are easy”, describes very clearly how to calculate GMT with lunar distances. Document written April 24, 2004 by FER.

    I cannot see how the factors “A” and “B” (“corner” cosines) could vary with the difference in azimuths between moon and comparing body (sun), since the only arguments in the cosine formula are “H_Moon”, “H_Sun” and “dist”.
    Document stating that the factors are 1,0 (100%) in case the bodies are on the same vertical (same azimuth) but are something else (within the cosine range) when they are not. I understand this is the case, but I cannot see it in the formulas.
    I am not a mathematician (obviously, I’m afraid) but quite familiar with the parts of the spherical trigonometry relevant for navigation.

    Best -
    Magnus Sjoquist

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