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    Re: Compass direction from Moon
    From: Frank Reed
    Date: 2020 Jan 16, 11:05 -0800

    The line through the horns of the Moon points fairly close to the north ecliptic pole. If you draw that line through the horns, and then follow it (northbound) for 90°, you'll be within 5° of the ecliptic pole. If you know something about the positions of the ecliptic and the poles of the ecliptic relative to the celestial poles and equator, then you can can deduce a fairly accurate north from this. For example, if the Moon is near RA=6h/18h (equiv to SHA=270°/90°) then the line through the ecliptic poles also passes through the celestial poles (extend the line through the horns for 90°+/-23° to reach the true north celestial pole).

    The document you've attached adds an unfortunate twist to this method by suggesting that an observer should follow the line through the horns to the horizon. This could lead to substantial, even dangerous, differences from true north.

    The northern points of South Africa are on the Tropic of Capricorn which makes things more interesting. 

    Frank Reed

       
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