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    Re: First Moon-Star Lunar
    From: Sean C
    Date: 2017 Dec 28, 03:26 -0800

    Ed,

    FWIW, I tried working your lunar using Frank's fomulae and your data. I got slightly different values for the SD of the Moon & the "dh"s and a very different value for "Q". My figures (differences in bold) are:

    SD Moon = 0.2724 ∙ 0°55.2' = 0°15.0'

    Aug. SD = 0°00.3' ∙ sin(37°50.1') = 0°0.2'

    Total SD = 0°15.2'

    "LDpc" = 95°53.8' - 0°15.2' = 95°38.6'

    dh_Moon = -0.0167°/tan(37°50.1'+7.32°/(37°50.1'+4.32°)) + 0°55.2' ∙ sin(37°50.1') = 0°42.3'

    dh_Star = -0.0167°/tan(36°10.7'+7.32°/(36°10.7'+4.32°)) = -0°1.4'

    A = 0.828

    B = 0.836

    Q = (0.55 ∙ (0°42.3')^2 ∙ cot(95°38.6') ∙ (1 - 0.828^2)) / 3438 = -2.47E-6

    "LDc" = 95°04.8'

    LD at 0000 UT = 95°07.8'

    LD at 0100 UT = 94°37.0'

    Interpolating, I get an "observed time" of 00:05:50.6. This is just -3.4 seconds difference from the actual time of 00:05:54. I did reverse the signs of dh_Moon & dh_Star when doing the final clearing calculation. Also, you can see that I am calculating these terms instead of looking them up in the N.A.

    What confuses me most is the difference in the value of "Q". Your figure of 0.15' is very different than the -0.0089" that I arrived at. Perhaps I am doing something wrong. (Frank, care to chime in?)

    In any case, congratulations on a very well done lunar!

    Regards,

    Sean C.

       
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