The solar system is home to eight individual planets, which are divided into two general types: terrestrial and gas giant. The gas giants are far larger than the rocky worlds, and they occupy the outer regions of our solar system. Interestingly, despite the immense sizes of the gas giants and the strength of their gravity, they are actually far less dense than the inner rocky worlds. This is due to the abundance of light elements contained within them, while the inner rocky worlds have a much higher abundance of heavy metals. Of all the planets in our solar system, Saturn has the lowest density, so low in fact that it could theoretically float.
Density Of Saturn
Saturn is nine times larger than Earth by size and 95 times the mass of our home planet. That makes Saturn a truly gigantic world when compared to Earth. Despite its size and mass, however, Saturn is the only planet in our solar system with a density lower than that of liquid water. Anything that has a density lower than water will inevitably float, and so theoretically, if you had a pool with enough water, Saturn would actually float. Saturn has a density of 0.687 grams per cubic centimeter, while water has a density of 0.997 grams per cubic centimeter.
Would Saturn Actually Float?
Despite Saturn’s density being lower than that of water, it would be impossible for the gas giant to actually float in real life. The amount of water required to actually contain Saturn would be so high that the sheer density of the water would no longer allow it to exist in liquid form. Even if this were to somehow be overcome, the gravitational pull of Saturn would simply draw in all the water, destroying any gigantic pool you attempted to make to contain the gas giant. Theoretically Saturn would float on water due to its low density, yet it would not be possible in the real world.