How Big Is Saturn?

Saturn is a colossal planet, with an equatorial diameter of 120,536 kilometers (74,898 miles). Saturn is the second-largest planet in the solar system, only surpassed by Jupiter. Despite its massive size, Saturn is surprisingly light for its volume. It occupies almost 60 percent of Jupiter’s volume but has only about one-third of its mass. This is due to its low mean density, which is about 70 percent that of water. If you could find an ocean large enough, Saturn would hypothetically float.

Saturn’s shape is not a perfect sphere; it is oblate, meaning it is flattened at the poles and bulging at the equator. This is due to its rapid rotation (a day on Saturn lasts about 10 hours and 45 minutes), which causes the equatorial diameter to be larger than the polar diameter. The polar diameter is about 108,728 kilometers (67,560 miles), making Saturn the most oblate planet in the solar system. This oblate shape is visible even through a small telescope.

Saturn is 95 times as massive as Earth but occupies a volume 766 times greater. This vast volume is filled primarily with hydrogen, which behaves as a liquid under the immense pressure found within the planet. The planet’s low density and large volume are key characteristics that distinguish it from the rocky inner planets of our solar system.