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    Re: Old style lunar
    From: Ken Muldrew
    Date: 2004 Dec 9, 16:36 -0700

    On 9 Dec 2004 at 17:41, Alexandre Eremenko wrote:
    
    > But the standard deviation of longitude is 0.3 deg,
    > that is 20' which probably better describes his accuracy
    
    Don't forget that his lunar position depends on a time-sight measurement
    as well as the lunar distance. His watch was often out by more than 10
    minutes each day, and the direction of error was unpredictable, so he was
    entirely dependent on the time sight. Any error there would propagate into
    the lunar error.
    
    > But this is probably easy to check. If anyone has a 1800
    > (or around) almanach. Just compare it with Frank's online
    > lunar dist predictor. As I understand it gives accurate results
    > for the XIX century.
    
    Bruce Stark was kind enough to send me some pages from the 1800 almanac
    this past summer. Perhaps I can check a few entries to see what Thompson
    was up against.
    
    Ken Muldrew.
    
    
    

       
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