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    Re: Question on Navigation: For Students or Mariners...
    From: Mike Burkes
    Date: 2012 Jan 5, 18:24 -0800

    Hi David essentially it is the old "Time Sight" formula for finding Longitude when the body is on or near the Prime Vertical. From a 1938 Bowditch pg 170 formula is sine squared one half t =secant L x cosecant P x cosine s x sine(s-h)
    Terms;t=body hour angle
    L=latitude
    P=polar distance=90 degrees-body declination if North, 90d+dec if South dec
    s=one half(h+L+p)
    h=body corrected altitude or Ho
    I found a math mistake s-h should be 39d 08m 23s NOT 39d 00m 23s. I am sure other nav members can provide a more detailed explanation. Hope this helps.
    Mike Burkes
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