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    Re: Lunars -Venus!
    From: Frank Reed CT
    Date: 2004 Apr 23, 22:05 EDT
    Jim T wrote:
    WT 22h 00m 21s
    WE 08s fast
    ZD +4-1 for DST = +3
    IE 2.7' on the arc
    hs 5d 57.1'
    GPS Fix:
    46d 16' 37.4" N
    063d 10' 48.8" W"

    I worked up your lunar based on the information you provided, and it turns out that your longitude by lunar is 063d 10' 48.81" W. Not bad!!


    Sorry, I couldn't help being entertained by the contrast in accuracy between your GPS numbers (0.1" in latitude is about ten feet) and the potential accuracy of a lunar distance longitude. Anyway, I did work your lunar just now (using my calculator at www.clockwk.com/cell/lunars.html , which is based structurally on Arthur Pearson's spreadsheet, and using almanac data from Omar Reis's online almanac) and the result indicates that your observation was short by about 3 minutes of arc. Did you use a shade to make Venus less dazzling? That 3 minute error corresponds to about 1.5 degrees error in longitude which puts you at sea off Inverness, Nova Scotia. Of course my clearing procedure may be in error. I just worked it up quick.

    Frank E. Reed
    [ ] Mystic, Connecticut
    [X] Chicago, Illinois
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