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    No Clock Longitude with Lunars
    From: Francis Upchurch
    Date: 2017 Apr 24, 12:09 -0700

    My favourite CelNav party trick is to find longitude without any timepiece and calculate the results without any electronics. 

    I have in the past averaged results from 10-40 miles out.(always at sea on my small boat).

    21st April, perfect weather, flat carm sea, managed multiple sun and moon alts and LDs sitting comfortably on a beach and got , I  supsect, very lucky results within 3-4 miles longitude v GPS.No clock but my son counted the seconds (1 thousand ,2 thousand) for relative time of each observation. I  graphed the results,  chose a "simutaneous" reading for LD, SunAlt, moon Alt. Used the cleared LD to find GMT, used that to reduce the Alts for lat and long by several methods, all giving similar results. 

    Anyone interested, I can send details.

    I'll probably never get these sort of  results again, but I live in hope!


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