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    Re: When did "time sights" fade away?
    From: John Huth
    Date: 2011 Jul 13, 17:14 -0400

    I teach a course where celestial nav. is only one small part of things, so I can't get in details like the intercept method.   

    I have the students use a protractor with a straw on the end of it, and a weight hanging down with a string.   They get the sun's altitude at different times of the day by centering the shadow of the straw projected on a piece of paper.   

    The latitude is taken knowing declination and the highest altitude, and longitude from the equal-altitude method.   Pretty straightforward and easy to understand.   

    Just to be a bit more compulsive, we then fit the curve to a parabola and see how much closer the fit gets than eyeballing the curve. 

    Basically no trig involved at all.

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