
 Kepler, Johannes (15711630) 
  Born in Weil der Stadt, southwest Germany, Kepler studied at the university of Tübingen and, as a graduate, was tutored by Michael Maestlin who introduced him to the heliocentric concepts of Copernicus. 
  Specifically, his theory states that if a sphere is drawn to touch the inside of the path of Saturn, and a cube is inscribed in the sphere, then the sphere inscribed in that cube is the sphere circumscribing the path of Jupiter. 
  Then if a regular tetrahedron is drawn in the sphere inscribing the path of Jupiter, the insphere of the tetrahedron is the sphere circumscribing the path of Mars, and so inward, putting the regular dodecahedron between Mars and Earth, the regular icosahedron between Earth and Venus, and the regular octahedron between Venus and Mercury. 
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