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    Re: Old style lunar
    From: Frank Reed CT
    Date: 2004 Dec 10, 16:07 EST
    Me earlier:
    >This web tool is doing relatively little calculation. The positions of
    >the Sun, Moon, and planets are stored in a ten megabyte database to the
    >nearest arcsecond. These positions are originally from the JPL numerical
    >integrations, so they are intrinsically very good.
    Alex E asked:
    "But where did you get this database from?
    And where can I get this database from?"
     
    There are lots of sources. I don't have a specific recommendation. Try "google" with search terms "JPL DE406"
     
    And:
    "Except by programming Meeus's many pages formula."
     
    Unless you intend to program a device with certain very specific limitations, algorithmic calculation of planetary positions is an obsolescent approach to the problem. If you decide you want to do that anyway --just for amusement-- I believe Willman-Bell (publisher of most of the astro-calc books by Meeus) has put the code on disk and makes it available for sale at a reasonable price.
     
    Frank R
    [ ] Mystic, Connecticut
    [X] Chicago, Illinois
       
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