Spheroid reasoned that Jupiter and Earth are oblate spheroids owing to their centrifugal force. Earth's diverse cartographic and geodetic systems are based on reference ellipsoids, all of which are oblate. A science-fiction example of an extremely oblate planet is Mesklin from Hal Clement's novel "Mission of Gravity". The prolate spheroid is the shape of the ball in several sports, such as in rugby football. Several moons of the Solar System approximate prolate spheroids in shape, though they are actually triaxial ellipsoids. Examples are Saturn's satellites Mimas, Enceladus, and Tethys and Uranus' satellite Miranda. In contrast to being distorted into oblate spheroids
Retrograde and prograde motion This has been suggested as an explanation for the preponderance of retrograde moons around Jupiter. Because Saturn has a more even mix of retrograde/prograde moons, however, the underlying causes appear to be more complex. With the exception of Hyperion all the known regular planetary natural satellites in the Solar System are tidally locked to their host planet, so they have zero rotation relative to their host planet, but have the same type of rotation relative to the Sun as their host planet, because they have prograde orbits around their host planet. That is to say, they all have prograde rotation