Ordering of the five planetary orbits in terms of the nesting of the five regular solids. This hypothesis formed the center piece of Kepler's 1596 The secret of the universe ( Mysterium cosmographicum ). Despites rather poor agreement between this model and observations, Kepler would cling to this idea to the end of his life. He issues a second edition of the book in 1621.
-Written and last revised 20 December 1997 by paulchar@ucar.edu.