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Re: Azimuth Formula Questions

From: Bill Noyce (no email)
Date: Tue Nov 01 2005 - 14:20:59 EST

  • Next message: Bill: "Re: Remember your first time?"

    Doug Royer wrote:
    > I learned and then started to use HO-211 on a regular basis. 28 pages of
    > data covers just about everything to reduce sights. But that is all it is
    > capable of doing. It can't compute GC sailings etc

    I'm confused. HO-211 should be able to compute GC sailings, sight
    predictions, and
    star identification just as well as HO-229 (though just like sight
    reduction, it takes more
    steps). For GC sailings, you of course use longitude difference as the LHA, and
    60*(90d-Hc) is the resulting distance. For star identification, the
    trick is to use observed
    azimuth as the LHA, and observed altitude as the declination; the
    resulting Hc and Z
    are then the star's declination and LHA, respectively. (I've probably
    fumbled this a bit,
    but doing this with HO211 is fundamentally the same as doing it with
    the tabular methods.)
        -- Bill


  • Next message: Bill: "Re: Remember your first time?"



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