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Re: Lunar eclipses and other things
From: Herbert Prinz
Date: 2004 Oct 29, 17:36 -0400
From: Herbert Prinz
Date: 2004 Oct 29, 17:36 -0400
Alexandre Eremenko wrote: > On the other hand, as far as I understand, "Ptolemy system" > was not Prolemy's invention, the principle belongs to > Hypparchus, and Ptolemy could only modify or improve it. It does not belong to Hipparchus at all. Hipparchus had no _system_, only isolated theories about the sun, the moon (a simple one), precession and probably a star catalogue. No planetary theory what so ever. Ptolemy had a model of the solar system. The physical aspects are described in the Planetary Hypotheses, the mathematical aspects in the Almagest. The defining characteristic of his system is the idea that the centre of uniform motion is not necessarily the centre of the orbit. This was the solution to the puzzle that Hipparchus could not solve. Herbert Prinz
