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    Re: Bowditch long term almanac
    From: Örjan Sandström
    Date: 2012 May 20, 03:23 -0700

    >Simply use sin d(i) = sin d(m) . sin L , where d(i) is the declination of the
    >day , d(m) is the maximum (sun´s) declination 23 deg 27´ , and L is the
    >longitude of the sun as measured from the closest solstice.

    interesting formula it would work if we use Latitude instead of longitude

    also I think you made a typo in quote below
    >May 20 is abt 60 days short of June 21 , or 60/90 x 90 deg = 60 deg
    in my almanac it is 32 days.

    If I was to use this my formula would be
    d(i) = sin^-1 (0.3979486 . sin (days_from_solstice))
    in the case of may 20th
    sin^-1 (0.3979486 . sin (91.25-32))=19°59.9'
    as correct number for Declination is 20°01.0'N at 00:00:00 may 20th it seems to OK.
    oddly it falls appart the closer i get to equinox
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