Two Sphere Universe

The theory of homocentric spheres was developed in the 4th century BC by Eudoxus of Cnidus. It was used for calculation of planetary motion under a geocentric. It is not a cosmological model, but only a mathematical representation. There was no claim to playing a physical reality. Each planet and the moon and the sun are associated with several interconnected spheres. All the spheres revolve about a common center, so homocentric ( with the same center ). All assigned to a planetary spheres are interconnected. So transfer the movements of the respective outer spheres on each innermost on which the star is located.

Through complicated mathematical operations could be calculated with this theory, the motion of planets and their location can be predicted in the sky. Nicolaus Copernicus rejected this theory because it offered no way to calculate the distances between each planet. The rejection of the theory of homocentric spheres was one of the mental steps that led him to develop his heliocentric worldview.

• About Holte theory (Astronomy)