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    Re: Stick shadows and sundial curves
    From: Tony Oz
    Date: 2021 May 31, 07:43 -0700

    Dear Adrian,

    If the gnomon (the stick) is at 51.2°N (at the latitude equal to star's declination) the shadow will draw the staight East-West line. Parabolas appear if the gnomon is at a latitude where the star is seen as setting/rising. Hyperbolas appear when the gnomon is closer to the equator than the star is (we are moving away from the pole).

    (I hope I did not confuse a parabola for a hyperbola!)

    Warm regards,
    Tony
    60°N 30°E

       
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