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    Re: Question re. A and B factors (corner cosines) lunars
    From: Magnus Sjoquist
    Date: 2012 Jan 24, 12:25 +0100

    As I understand the matter:


    Both bodies on the same vertical:


    ?A-factor? (cosine Moon-corner):

    Moon above Sun:

    ZMS = 180 deg.

     Moon below Sun:

    ZMS = 000 deg.



    ?B-factor? (cosine Sun-corner):

    Sun above Moon:

    ZSM  = 180 deg.


    Sun below Moon:

    ZSM = 000 deg


    (With both bodies on the same vertical the resulting correction is the difference in corrections for the two).

    ----Ursprungligt meddelande----
    Från: lars.h.bergman@gmail.com
    Datum: 2012-01-24 11:40
    Till: <NavList@fer3.com>
    Ärende: [NavList] Re: Question re. A and B factors (corner cosines) lunars

    In 17914 Frank wrote:
    "If the Moon is directly above the Sun (its altitude would then be 75 degrees), the angle ZMS is zero and its cosine is +1. If the Moon is directly below the Sun (necessarily at an altitude of 15 degrees), the angle ZMS is 180 degrees and its cosine is -1."

    Isn't it the other way around?

    Lars, 59N 18E
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