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    Re: 1768 Almanac
    From: Frank Reed CT
    Date: 2007 Apr 18, 18:09 -0700

    Dave W wrote:
    "setting the observation site to Greenwich Observatory and itererating
    to find local apparent noon for 14 Jan 1768, one finds UTC  to be 12h
    9m 31.626s."  etc.
    Just a reminder, the lunar distance predictions on my web site ALREADY
    provide the lunar distance tables in Greenwich Apparent Time (or
    Greenwich Mean Time if prefered) for any date. You can set it to
    produce tables with distances in degrees, minutes, and tenths or in
    degrees, minutes, and seconds. The latter allows direct and immediate
    comparison with the published tables. This online tool has been
    available for exactly this purpose for some three years now. Enjoy!
    For example, looking at a page from the Nautical Almanac for 1778, we
    see listed lunar distances from the Sun of 124d 0' 4", 110d 40' 2",
    97d 29' 7" at noon GAT on October 10, 11, 12 respectively. By my
    calculator, the correct distances were actually 123d 59' 58", 110d 39'
    41", 97d 28' 36" so the errors are 0.1, 0.35, 0.5 minutes of arc
    corresponding to longitude errors of approximately 3, 10, and 30
    minutes of arc.
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