[Doctor Stochastic]

I should add that the heliocentric theory also allows the derivation of laws that a heliocentric theory cannot. The equal-area in equal time law and the law that the farther from the center of rotation, the slower the movement. Both fail in the geocentric system.

[stremba]

True. This also brings up another characteristic of a scientific theory, namely fecundity. Good theories typically help science to understand other phenomena.