quote:
Originally posted by w_fortenberry:
But the planetary orbits are said to be eliptical. This does not fit with your statement that "the earth/sun system also orbits a common point." Can you provide an explanation for the elliptical orbits of the planets?
All orbits are eliptical (apart from parabolic and hyperbolic ones at any rate) even circular ones which are just special cases of elliptical orbits where e = 0....
And the point orbited around is one of the focus points of the ellipse, termed the principle focus in the case of orbiting bodies...