Kepler attempt to associate each of the six known planets with one of the Platonic solids [La tentative de Képler d'associer chacune des six planètes alors connues à l'un des solides platoniciens].
Johannes kepler found that each of the five Platonic Solids
could be inscribed and circumscribed by spherical orbs, nesting these solids, each encased in a sphere and the associated to the six known planets (at that time...).