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    Re: Universe of the ancient Greeks.
    From: Frank Reed CT
    Date: 2006 Mar 14, 02:47 EST

    Lu Abel, you wrote:
    "True, but then why  didn't the rest of the "learned" crowd jump on the
    idea as a solution for the  motion of the planets?   Or were they more
    interested in a  "logically satisfying" solution than one that provided
    the easiest solution  to a problem?"
    For those who were engaged in the debate, the problems  were observational as
    well as "philosophical". If the Earth travels around the  Sun, why don't the
    stars display parallax. After all, each retrograde loop is  nothing more than
    parallax from the Earth's motion. This lack of parallax of the  stars is real
    *evidence* that the Earth is not moving --unless, of course, it  turns out
    that the stars, which otherwise so closely resemble the planets, are  actually an
    entirely different class of objects thousands of times farther away.
    And don't forget that the motions of the planets, and the Moon, too,  display
    LARGE anomalies that are not satisfied even by Keplerian elliptical  motion.
    The "evection" of the Moon's motion, for example, has been known at  least
    since Hipparchus, but it was not explained until Newton. Likewise, the  longitude
    of Saturn oscillates away from the position predicted by Kepler's laws  by up
    to a full degree because of the gravitational influence of Jupiter.
    42.0N 87.7W, or 41.4N 72.1W.

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