Comment on the Origin of the Equant Papers by Evans, Swerdlow, and Jones

  title={Comment on the Origin of the Equant Papers by Evans, Swerdlow, and Jones},
  author={Dennis W. Duke},
  journal={Journal for the History of Astronomy},
  pages={1 - 6}
  • D. Duke
  • Published 1 February 2005
  • Physics, Geology
  • Journal for the History of Astronomy
1. determined the apparent value of 2e, the distance between the Earth and the center of uniform motion around the zodiac, corresponding to the zodiacal anomaly. One can use a trio of oppositions, some other procedure based on oppositions (e.g. Evans), or in principle, any synodic phenomenon, but in practice oppositions would be the clear observable of choice. 2. determined the apparent value of e , the distance between the earth and the center of the planet’s deferent, by looking at some… 
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