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    Re: Star positions.
    From: Örjan Sandström
    Date: 2013 Jan 6, 01:59 -0800

    this was meant to be a basic "emergency" almanac.
    it is Not intended to be a 100% accurate almanac and if it works i am just happy with that.
    I found the rates of change in both dec and SHA by taking coordinates from NA over a 10 year span for each of the stars and feeding to a spreadsheet.
    this was my "X-mas 2010 project".
    The project also included sun, something I never got working quite right.
    I later found out from Geoffrey Kolbe that I had to give separate number for each day over the four years of the leap year cycle to get it near right, my error was that I had tried to use the "Bowditch LTA" with same number for whole quadrennial.
    the sun part is something I have yet to find time to do right, not even close to priority As I use the Kolbe LTA quite frequently anyway I somehow did not bother...
    One interesting error I made on first version was using the SHA-Aries for Jan 1st, when trying to verify I always got SHA wrong, later someone on this list pointed out that I got correct value for next day...
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