Why does Saturn have rings?

Scientists have ideas about why Saturn has rings, but no one knows for sure.

What are Saturn's rings made of? Are they solid like the CD you used to make your model? Or are they made of many particles dancing in formation around the planet? Three robotic spacecraft from Earth have already visited Saturn--Pioneer 11, Voyager 1, and Voyager 2. They revealed many surprising things about Saturn's rings.

The small color differences in Saturn's rings have been enhanced in this picture from Voyager 2 data.

This Voyager 2 picture shows the gap in the rings called the Cassini Division.

Over 60 bright and dark ringlets show up in this color enhanced image from Voyager 2 data.

The rings are about 400,000 kilometers (240,000 miles) wide. That's the distance from the Earth to the Moon! But the rings are as little as 100 meters (330 feet) thick. They range from particles too tiny to see to "particles" the size of a bus. Scientists think they are icy snowballs or ice covered rocks.

There are actually many rings--maybe 500 to 1000. There are also gaps in the rings. (That's why we put some black rings on our model Saturns.)

A new spacecraft is now on its way to study Saturn much more thoroughly than the earlier spacecraft could. After a seven-year journey, the Cassini (ka-SEE-nee) spacecraft will arrive at Saturn on July 1, 2004. It will go into orbit around Saturn and study its rings, its many moons, and the planet itself.

Cassini also carries a probe, called Huygens (HOY-guns), that will parachute into the atmosphere of Saturn's giant moon Titan. Huygens will send back information on this strange world whose surface we have never seen.

Here's a QuickTime movie of the Cassini spacecraft releasing the Huygens probe (665 Kb).

Here's a QuickTime movie of the Huygens probe landing on Titan (632 Kb).

What exciting new discoveries Cassini and Huygens will make!