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    Re: September Equinox computation
    From: Herbert Prinz
    Date: 2002 Sep 24, 22:58 +0000

    Hi guys,
    I was already wondering how Dan Allen could be off by more than 3 minutes
    using Meeus' algorithm, but no way did I believe that the JPL ephemeris plus
    Novas routines could be early by 3.5 minutes, whether its all written in
    Fortran, C or Cobol.
    So I plug the numbers into my carefully re-written Pascal version of the
    Novas routines using DE200 and obtain (by doing what I described in my
    earlier message) for the time of this year's autemnal equinox  4:55:24 UT1.
    This value has the advantage that it agrees with what Meeus publishes in
    "Tables of the Sun, Moon and Planets", as well as with what the USNO thinks
    it should be. (see  Earth's Seasons, etc. 1992-2005  ). This is probably not
    a coincidence.
    Herbert Prinz
    > Jay Borseth wrote:
    >   The results I'm getting put the equinox at:
    >      4:51:54 AM GMT on 23 Sep 2002, crossing at E 105 degrees 9' 56".
    > Dan Allen wrote:
    > PS - My computations for this year put the equinox at 4:52:04 AM GMT on
    > 23 Sep 2002.

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