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    Fall Equinox
    From: Bill B
    Date: 2008 Sep 21, 01:11 -0400

    Is it possible to predict, within a second or two, an equinox using the
    Nautical almanac?
    
    Internet sites state 15:44:18 UTC, 22 September, 2008 as the moment of fall
    equinox.
    
    The almanac has a nominal "d" of 1' per hour, but 0'.9 d as the interval
    bracketing the transition from north to south declination of the sun.
    Interpolation gets me within a couple of minutes of the published time, but
    rounding in declination seems to make an exact calculation difficult at
    best.
    
    Further complicating matters, IF memory serves a scholarly review (complete
    with diagrams) of the the relationship between the First Point of Aries, the
    celestial equator, and the ecliptic pointed out the relationship is not as
    simplistic as I might have expected.  As usual, when memory fails I blame
    George Huxtable for the post. 
    
    If once again I am mistaken about the author, would the above-mentioned list
    guru please give a reference to the date and subject of the post, or re
    post?
    
    Thanks
    
    Bill B.
    
    
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