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    Re: Time Sight and Ex-Meridian by Bygrave
    From: Brian Walton
    Date: 2021 Apr 7, 00:56 -0700


      I could have titled my post "Time Sight and Ex-Meridian by Greg Rudzinski's All Haversine Doniol."  The method of obtaining azimuth and intercept is irrelevent, be it internet wizardry or leafing through tables.

      The diagram in my post encapsulates the major methods used between Cook and scientific calculators, by magnifying a small corner of the PZX triangle. The hard work has been done, and time longitude, and lat correction jump out graphically. I used Bygrave as an example, because all the old methods can be seen, with blissfull ignorance of logs and trig ratios.

       Unless higher authority requires a Noon fix for the official logbook, once one can find an intercept, meridian sights lose their importance. If intercepts are short, azimuth also might be precision overkill, where a compass bearing or star finder might do.

       Thank you for your comments,

    Brian Walton

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