• Saturn has the lowest mass density of any planet in the solar system, low enough for the planet to float on water, and this means that Saturn is primarily composed of the lightest element, hydrogen.

• Saturn's rapid rotation has pushed its lightweight material out in the planet's middle, creating the most pronounced equatorial bulge of any planet.

• Saturn is just a great big liquid drop, covered by a thin atmosphere of gas, slightly smaller than Jupiter and less than a third of its mass.

• Liquid hydrogen is compressed inside Saturn's depths to form an electrically conducting, liquefied metal.

• There is no solid surface anywhere inside Saturn, though it might have a core of melted ice and molten rock that is about ten times as massive as the Earth.

• Saturn radiates almost twice as much energy as it receives from the Sun, and most of the planet's excess heat is generated by helium raining down into its liquid metallic hydrogen core.

• Saturn's rings are completely detached from the planet and separated from each other.

• The rings of Saturn are not solid, but instead composed of innumerable small water-ice particles and larger chunks of water ice.

• The icy constituents of Saturn's main A, B and C rings are as big as hailstones, snowballs and even icebergs; there are more smaller ones, but the big kind supply most of the ring mass. […]