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    Re: Longterm Sun's GHA and Dec: what's under the hood?
    From: Robert VanderPol II
    Date: 2018 Dec 6, 18:44 -0800


    There are a number of ways to construct a long term almanac.  Most of them depend on the fact that the sun's position repeats on almost exactly a 4yr cycle with slow drift from cycle to cycle which can be predicted. The 4yr cycle is predicated on the fact that solar years is almost exactly 365.25 days.

    The manner with which every long term almanac is arranged depends on the arranger and only a few long term almanacs have been created so I don't thnk there is going to be much info on how to create them.

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