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    Re: Celestial Navigation In The Gps Age: Typos?
    From: Tony Oz
    Date: 2017 Sep 1, 01:20 -0700


    Thank you everybody for the clarification of the LL vs UL "quick and dirty" correction values - got it.

    Now a question about the terminology used for the formula 7.5e: whether the "LHA" name is really appropriate for the angle returned by the cos-1 function. My take is - the name should be different if the angle is to undergo further modifications according to some rules. It must be - I think so - either the "LonD" (the term already used in the book, the "longitude difference"), or the "t" - the meridian angle. We get the LHA proper only after we apply the required rules to its value (and/or its sign).

    As a nit-picking: the formula 7.5d would look better with the "±" in the cos(A - B) term.

    The book is really great and I hope Mr Karl will have a chance to make it even better.

    Thank you all again!

    Warm regards,



    The "Position without St. Hilaire" article really made me thinking, I'll search in the NavList archive for the relevant discussion - and ask a question in a separate post.

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