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    Re: GMT from Moon and Body Observed Altitudes...??
    From: Ron Jones
    Date: 2019 Feb 20, 09:57 -0800

    Tony Oz on Date: 2019 Feb 20, 00:38 -0800 wrote:

    You must realise that the mentioned ±0.5° uncertainty would get into the time thus calculated - most probably - with some VERY significant multiplicand. The GMT thus obtained will be very unreliable.

    Yes the calculated UT Based on the equation, shown below, Is a lot more sensitive to COS(delta_Zn) than I first realized.  :

    GLD = COS-1[SIN(HoBody)•SIN(HoMoon) + COS(HoBody)•COS(HoMoon)•COS(ZnBody-ZnMoon)]

    In the example I used the exact values for Ho & Zn produced a calculated UT of 11:19:15 which was only one second slow of the exact UT of 11:19:16.  When the delta_Zn was increased by 1° the calculated UT was 10:07:27 & when the delta_Zn was decreased by 1° the calculated UT was 12:29:15.

       
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