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    Re: Old style lunar
    From: Fred Hebard
    Date: 2004 Dec 9, 22:47 -0500

    On Dec 9, 2004, at 8:35 PM, Frank Reed wrote:
    
    > Alex wrote:
    > "Perhaps Frank can also tell us what accuracy can be expected
    > from his lunar "predictions" for 200 years ago."
    >
    > +/- 1 arcsecond or better.
    >
    > Here's a specific sample from the 1778 Nautical Almanac (N.A.)
    > compared with my online lunars predictions (modern ephemeris). Angles
    > in degrees, minutes, and seconds, dd.mm.ss:
    > Noon, March 20, 1778
    > Sun-Moon distance from N.A.: 65.19.52
    > Modern ephemeris: 65.19.58
    > Noon, June 18, 1778
    > Sun-Moon distance from N.A.: 84.02.18
    > Modern ephemeris: 84.02.04
    > Noon, August 25, 1778
    > Sun-Moon distance from N.A.: 39.49.12
    > Modern ephemeris: 39.49.17
    > Noon, November 14, 1778
    > Sun-Moon distance from N.A.: 52.37.19
    > Modern ephemeris: 52.37.44
    
    Frank,
    
    The only one that's somewhat serious is Nov 14, 1778, and that's out by
    25" of arc.  This can't explain discrepancies of 1 degree of arc!
    
    Fred
    
    
    

       
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