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    Re: Latitude and longitude around noon
    From: Frank Reed
    Date: 2017 Mar 30, 10:09 -0700

    Peter Hakel using the standard multi-sight methodology (which, by the way, for those reading along is the methodology for combining multiple sights found in the Nautical Almanac since the 1980s) got a position of N 41° 27.3’, W 71° 27.2’. Robin Stuart using a parabola fit got 41°27.2′N, 71°26.8′W. The distance between those two positions is 0.3 nautical miles so about as good as you could expect. 

    My actual position on that very windy day was 41°27.0' N, 71°23.9' W which is 2.3 nautical miles east of the average of the above two positions. Using sights like these around noon and proper methodology (which can be quite simple and does not necessarily require a lot of math work), one can expect a latitude accurate to a mile or so, and a longitude accurate to +/- three to seven miles, depending on details. So these results are quite good. On this blustery day, I was hunkered down behind some rocks to get out of the wind, and the biggest problem I had was that I managed to put my leg to "sleep" by sitting on it funny while taking sights.

    More later...

    I was busy earlier in the week building crystal radios (I have built three different designs in the past two months, and I have a class building fourteen of them right now), and for the next few days I'll be busy prepping for my "Celestial Navigation 19th Century Methods" class (this weekend at Mystic Seaport). As you can tell, I'm preparing for a trip back in time to 1901. I will require no 21st century technology ...excluding my time machine.

    Frank Reed

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