Question

Why are jupiter and saturn not perfectly spherical? they rotate rapidly. they have very active auroras that heat the atmospheres along the poles. they have storms that develop preferentially along their equators they formed from the collision of two large planetesimals?

Answer 1

They spin rapidly.

Jupiter and Saturn have equatorial bulges and appear like a squished ball. The outer edges of the equator try to keep up with its rotation and move faster than the center. The bulges are shaped as the two planets spin very quickly.