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    Sun Polynomials again
    From: Gordon Talge
    Date: 2002 Oct 29, 22:42 -0800

    This is another version of a polynomial approximation of the
    Sun for the month of November.
    
    -- Gordon
    
    --
                                  ,,,
                                 (. .)
    +-------------------------ooO-(_)-Ooo------------------------+
    | Gordon Talge WB6YKK               e-mail: gtalge{at}pe.net    |
    | Department of Mathematics       http://www.lbusd.k12.ca.us |
    | Wilson High School                  Long Beach, CA         |
    | (o-    Debian / GNU / Linux                                |
    | //\    The Choice of the GNU Generation                    |
    | v_/_                  .oooO                                |
    |    - E Aho Laula -     (  )   Oooo. - Wider is Better -    |
    +-------------------------\ (---(  )-------------------------+
                               \_)  ) /
                                   (_/
    This is a polynomial series like the British "Compact data for
    navigation Al astronomy". I have not seen the "Official" polynomials
    for 2002, so I don't know how compare, but they are probably not
    exactly the same.
    
    The time argument is a little different from the USNAO "Almanac
    for Computers". For these polynomials it is:
    
    x = ( d + GMT/24 ) / 32
    
    Example: GHA, dec and SD required for the Sun on Nov 11, 2002
    at 11h 11m 11s.
    
    So, d = 11, GMT = 11.18639h  and x = 0.35832
    
    Evaluating the 4th degree polynomial we get GHA-GMT = 12.26632h
    Now add the GMT used so GHA in hrs = 12.26632+11.18639 = 23.45270h
    Remove multiples of 24h. In this case we don't have to.
    
    GHA = 23.45270 x 15 = 351.79056 or 351 degs 47.4'
    
    For Dec evaluating the polynomial we get -17.43920 or S 17 degs 26.4'
    
    For SD we get 0.2696 x 60 = 16.2'
    
    The Nautical Almanac gives: GHA 351 degs 47.4' Dec S 17 degs 26.3'
    and SD 16.2'.
    
    
    The British polynomials are 5 decimals for GHA-GMT and 4 for Dec,
    and 4 for S.D., but only 2 terms for S.D.
    
    There is also a statement that "Corrections have been incorporated
    in the data for Venus and Mars to allow for their phase, so that the
    position obtained from the polynomial coefficients...is for the
    observed centre-of-light." Not sure what this correction is and
    how to apply it yet for the planets.
    
    
                             Dates:  Nov.  1 - Nov. 32
    
                     Aries        Sun          Sun           Sun
                     GHA          GHA-GMT      Dec.          S.D.
    Term              h            h            °            °
      0             2.60818     12.27251     -13.9768       0.2688
      1             2.10270      0.02402     -10.4206       0.0022
      2             0.00003     -0.11192       1.8732       0.0003
      3             0.00002     -0.01273       0.6966      -0.0008
      4            -0.00003      0.00866      -0.0658       0.0003
    
    
    

       
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