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    Re: Tycho Brahe Mars oppositions
    From: Frank Reed CT
    Date: 2004 Dec 1, 00:37 EST
    Omar R wrote:
    "I'm trying to validate the results of
    a planet position algorithm for early
    dates. So I searched for the oldest
    Mars observations I could find."
     
    There's really no reason these days to use a "planet position algorithm". The JPL planetary position integrations (e.g. DE406) are accurate to about a second of arc for any time in the past thousand years (and the Moon position is accurate to about 0.1*T^2 arcseconds where T is the number of centuries back in time). These integrations have been validated and checked against the best available historical data and they are likely to be far more trustworthy than Tycho's observations. I use the reuslts of these integrations as the basis for my online almanac and lunar distance predictions:
     
    Frank R
    [ ] Mystic, Connecticut
    [X] Chicago, Illinois
       
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