NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Universe of the ancient Greeks.
From: Frank Reed CT
Date: 2006 Mar 14, 02:47 EST
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. -FER 42.0N 87.7W, or 41.4N 72.1W. www.HistoricalAtlas.com/lunars