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    Re: M.O.O. Alternative table 1
    From: Russell Sher
    Date: 2001 Nov 28, 2:47 AM

    Hi Eric - welcome to the list...
    As far as the Alternative table 1 goes, I don't know of any gain in using
    this for small boat navigation where (relative) ground speeds are minimal.
    The tables were of course designed with aviators in mind. I have never heard
    of (or read of) any emphasis on using them for marine navigation.
    As far as your second question goes; Remember that the tables are simply
    precomputed formulae.(where Hc and Zn are computed using Dr Lat, LHA and DEC
    as arguments)
    Volume 1 simply exploits the fact that the declinations of stars change very
    little and so technically, there may be a slight loss of accuracy here
    between extremes of a year. However there is the correctional table supplied
    for this purpose.
    Also, by dividing Volume 1 into north and south hemispheres the table will
    of course give azimuth Zn, directly (as opposed to azimuth angle Z which
    must be converted.)
    But in any case Ho249 is not as accurate as Ho229 - note that in Ho249 the
    azimuth angles and calculated altitudes do not give decimal point precision.
    For small-boat navigation this is quite acceptable. This should further
    suggest that there is not much gain in using Alt table 1. (perhaps other
    opinions will prevail...!)
    Volume 1 also forms a star identifier/locator by precomputing the Hc and Zn
    of the body.
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