NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
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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