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    Re: Out of Date Almanac
    From: Gary LaPook
    Date: 2009 Dec 07, 18:42 -0800

    Works fine for the sun and stars, not planets or the moon. For the stars
    just add the constant of 2.1' to GHA Aries, which is exact. The data for
    the sun will be correct within about two tenths of a minute for GHA and
    within three quarters of a minute in declination. Unfortunately these
    differences vary during the year so a simple constant, such as used for
    GHA Aries, wont work for the sun data. For practical navigation you can
    ignore the changes of positions of the stars or just zerox the star list
    from December 31, 2009 and carry it in the 2006 almanac.
    You can avoid this whole problem by getting a copy of  Geoffrey Kolbe's
    Long Term Almanac which provides accurate data until 2050.
    Greg Rudzinski wrote:
    > Any opinions on using a Nautical Almanac that is four years out of
    > date? I bring this up because there are old almanacs available on
    > Amazon.com from $2 to $10.  New Nautical Almanacs have gotten
    > expensive so my plan is to use a 2006 for the upcoming year 2010.
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