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    Re: First Moon-Star Lunar
    From: Antoine Couëtte
    Date: 2017 Dec 26, 07:45 -0800

    Dear Ed,

    Thank you for publihing your first Moon-Star Lunar.

    Although I am not familiar with the method you are using - definitely a simple one - nor with your subscripts (see also a pending post named "Publishing heights" ), I might have found a typo in your published data, which gave me a good headache to solve.

    Now, I am convinced that "Ho's" refers to geocentric heights.

    Regarding such typo, please have a look immediately below :

    Dec 24th, 2017  GMT 00:05:54  Moon's age was 5.7 days, a waxing crescent.

    Using Reed's algorithm in my HP calculator ...

    Moon

     Ho 37deg 50.1'

     Corr    -42.8'

     SD+Aug   15.1'

    Aldebaran

     Ho 36deg 10.7'

     Corr    +01.3'

    LDa     95deg  3.8' far should it not rather be “95deg 53.8’far ?”

    LDpc    95deg 38.7'     …  especially since LDpc + SD+Aug =95deg 53.8’ ???

    From my own software, with the [corrected typo] data you have published, I am finding that your clock error is below 2 seconds of time, which is also fully confirmed by Frank's Computer.

    Here are my "backward engineered" height values, which are to be construed as "Sextant values with Height of Eye = 0 and instrument error = 0 " . Hence Refraction, ( 50°F, and 29.92"),  [augmented] SD and parallax corrections remain to be computed. Here are my "raw data" which you can directly feed into Frank's Computer :

    24 Dec 2017, UT = 00h05m54.0s (TT-UT = +69.5 s, not necessary here actually since Frank's has his own value which should be close enough from this one) . I am just hoping now that temperature has not gone above 50° F .

    Observed Sextant Distance : 95°53'8 (far Limb), Aldebaran height : 36°12'0 , and Moon LL height = 36°52.3' or Moon UL height = 37°22'6

    If you feed Frank's computer with these "backwards engineered" raw data, you will get an exceptional result : Error in Lunar 0.0' with Approximate Error in Longitude 1.0' 

    Additionally, and from your published data, once your typo is corrected, I am locating you at : N28°41'1 W082°17'9 , central Florida, yes ... not far from its West Coast.

    What was your actual position then ?

    Best Friendly Regards,

    Antoine Couëtte

       
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