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    Re: Aldebaran occultation
    From: Lars Bergman
    Date: 2017 Mar 6, 06:26 -0800

    I tried to obtain GMT from Alex's occultation. I assumed a longitude of 87°W and used GMT=4h as approximate time of the event. Then I followed the procedure shown in Wrangel's textbook on navigation, Stockholm 1910, slightly modified solving for SHA instead of right ascension. My favourite Burton's tables was not sufficient for log sine of very small angles, so I had to calculate those separately. Perhaps it was just good luck but the result is only a few seconds from that Alex noted.

    I am not sure if my solution is correct, have the necessary precision everywhere, or use too many figures somewhere, nor have I done any sensitivity analysis. My attempt attached.

    Lars 



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