Kepler's Solar System Model, Rings

Cross section of Kepler's 3D model. The annulus is the 2D plane section
of a 3D spherical shell by the plane of the Earth's orbit. The ellipse of the planet's orbit stays
within the ring, but grazes both boundary circles,
as shown here.

The magenta ring corrersponds to a fictitious planet with eccentricity 1/7. The parameters R max and R min are the radii of the bondary circles of the rign. The semi-major axis (a) and focal distance (ae) of the elliptical orbit are shown also. Note that the Center (of the ellipse, black dot) is above the Focus (center of the ring, magenta dot).

Rev'd 24 dec 2001 by ralph abraham