Why do the planets not orbit the sun in a perfect circle?
A perfect circle implies a planet that’s a perfect sphere (nearly impossible–or, at least, very unlikely) and no other gravitational force other than the body at the center of the orbit affecting its rotation. In our Solar System, there are many things that exert their own gravitational forces, least of which are the other planets and moons. It’s not an impossible situation by any means; it’s just extremely unlikely given the reality of the universe.
