aturn is an oblate spheroid, meaning that it is flattened at the poles, and it swells out around its equator. The planet’s equatorial diameter is 120,536 km (74,898 mi), while its polar diameter (the distance from the north pole to the south pole) is 108,728 km (67,560 mi); a 9% difference.[14] Saturn has a flattened shape; it is due to its very fast rotation, rotating once every 10.8 hours.[2] Saturn is the only planet in the Solar System that is less dense than water. Even though the planet’s core is very dense, it has a gaseous atmosphere, so the average specific density of the planet is 0.69 g/cm³ (less than the density of water). This means if Saturn could be placed in a large pool of water, it would float.[15]
