Saturn

Saturn’sfast spin and

low density make itnoticeably flattened.

Saturnand its ringsare shown here withtheir correct sizes relative to the Sun.

Saturn's moon Enceladus (right) is the only place in the solar system besides Earth on which geysers

of liquid water have been seen.

1 Saturnian day = 10.6 Earth hours1 Saturnian year = 29.4 Earth years

Saturn, like Jupiter, is a gas giantmade mostly of hydrogen and helium. Despite its size, Saturn is less dense than water!

Orbiting Saturn’s equator are its rings. These rings are made of an enormous number of chunks of ice, probably with bits of rock in them. The chunks range in size from huge boulders down to tiny crystals. Each chunk is on

its own orbit around Saturn, but the chunks are so close together that each chunk suffers a gentle collision every few hours. Moons orbiting in or near the rings change the orbits of ice chunks in certain locations and clear

out gaps in the rings. Astronomers aren't sure how old Saturn's rings are, or how long they will last. They may

be gone in "only" a hundred million years!

Saturn's largest moon, Titan (below), is the onlymoon with a significant atmosphere. Its atmosphere is made of 98% nitrogen plus2% methane and otherhydrocarbon gases. This “smog”completelyhides Titanbehind anopaquehaze.

Titan is the most distant object on which humans have landed a spacecraft.

The Huygens probe sent back this photo (right) of a flat plain strewn with

“rocks” made mostly of water ice.

Titan is so cold near its poles

that it has lakes of

liquid methane (seen at

right in a false

colour radar

image).Photo credits: NASA/JPL/Space Science Institute Titan surface photo credit: ESA/NASA/JPL/University of Arizona