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    Re: Old style almanacs from new machines
    From: Frank Reed CT
    Date: 2006 Nov 16, 02:25 EST
    Ken M you wrote:
    "Basically, the program creates a text file for a given month with all the
    ephemera of the old almanacs. You can get the same thing from Frank Reed's
    web-based almanac; this just gives you a monthly printout. When I first
    wrote it I tested a bunch of random dates against Frank's almanac and they
    agreed, but really, you would have to be completely insane to use
    something like this for actual navigation, so the testing hasn't been very
    rigorous. I wrote it just for the fun of calculating lunars by hand, much
    as it was done ca. 1800, but using my own sights rather than historical
    data. "
    I see that your values agree with the ones in my online almanac exactly about 75% of the time and differ by one second of arc about 25% of the time. Both are accurate well beyond the necessities of the various navigational methods, including lunar distances. Round-off error alone would have us disagree at the one arc second level about one-sixth of the time. I guess the additional 9% comes from small differences in the way we've coded the almanac data. :-)
    Looks nice, too. I got a kick out of your "traditional" star names for the navigational stars.
    You say that someone "would have to be completely insane to use something like this for actual navigation". Isn't that one of our goals on the list?!
    42.0N 87.7W, or 41.4N 72.1W.

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