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    Re: Out of Date Almanac
    From: Gary LaPook
    Date: 2009 Dec 08, 22:11 -0800

    For using just the stars you can just  memorize the GHA of Aries for 
    0000Z December 31, 2009 which is 99� 33.4', and remember that Aries 
    advances 59.139' per day. Then looking at a calender, or daytimer 
    (preferably one that shows the number of the day of the year ) or 
    figuring out the day's number ("thirty days have November ...) in your 
    head, you can multiply 59.139' times the number of the day of the year 
    and add this to 99� 33.4' to find GHA Aries for 0000 Z. The reason to 
    use December 31, 2009 instead of January 1, 2010 as the starting point 
    is that January 1 is day 1 of the year. If you start from January one 
    then you must subtract one from the day of the year number to show the 
    number of days that have elapsed from the starting point, starting on 
    December 31 avoids this extra step. Then compute the increment for GHA 
    Aries for the time of day at the rate of 15.041� per hour.
    If you have memorized the SHAs and declinations for a few stars you will 
    have all the information you need to compute the Hcs for a stellar fix.
    Or, if you don't trust your memory.
    Just rip out the left hand December 31st page from your N.A for 2009 (or 
    zerox it), which contains the GHA Aries for 0000Z and the list of star 
    positions, and write along the bottom of the page "59.139' per 
    day----15.041� per hour" and then you can compute the Hcs for your star 
    fixes for a year to an accuracy of better than one minute of arc.
    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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