Like Jupiter, Saturn is a large, gaseous planet composed mostly of the gases hydrogen
and helium. Saturn has a magnetic field 1,000 times stronger than Earth's but not
as strong as Jupiter's. Due to its gaseous nature, Saturn's density is so low that
it could float in an ocean of water. It probably has a core similar to that of Jupiter.
It is covered with cloud bands, some forming cyclonic patterns like Jupiter's, but
the colors appear more subdued than do Jupiter's because of an atmospheric haze
that covers the clouds.
Saturn is surrounded by a spectacular ring system (see the picture above). Galileo
observed these rings in 1610, but he did not identify them as rings. Instead,
he believed Saturn was actually 3 separate planets. In 1655, using a more powerful
telescope, the Dutch astronomer Christian Huygens was able to see a flat, apparently
solid ring around Saturn. Later, with even more powerful telescopes, astronomers
were able to identify separate rings.
The cameras of Voyagers 1 and 2 (spaceships sent by NASA) revealed that there are
really tens of thousands of rings extending from about 4,300 miles (7,000 kilometers)
to 46,000 miles (74,000 kilometers) beyond Saturn's atmosphere. They are made of
ice and ice-covered particles that range from the size of a speck of dust to the
size of a house.