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    Re: Position from altitude and azimuth.
    From: Geoffrey Kolbe
    Date: 2020 May 12, 02:55 -0700

    What's with all this iteration...?

    I presented equations for finding LAT and LONG from the measured altitude Ho and measured azimuth Zo of a celestial body back in 2008 at the Mystic navigation conference when I gave a talk about navigating with a theodolite... I am shocked nobody remembers!

    In this case, we have Ho = 54° 56', Zo = 120° 28' . The DEC for the sun was 16° 46.9' and the GHA was 45° 51'

    Let MA = Sin-1(Sin Zo · Cos Ho / Cos DEC) = 31° 09'

    Since Zo is < 180, LHA = 360 - MA = 328° 51', from which we get a longitude of 77° West in the usual way

    We can find the latitude from:

    LAT = Sin-1[(Sin Ho·Sin DEC - Cos Ho·Cos DEC·Cos MA·Cos Zo)/(1 - (Cos DEC·Sin MA)2)] = 39° North

    The end

    Geoffrey Kolbe

       
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