You have probably heard about, and looked at pictures of, the rings around the planet Saturn. On average, these rings are about twenty meters thick and they are made up of 93% ice and about 7% carbon. There is actually a pretty large distribution of particle sizes in these rings, ranging from specks the size of dust to chunks of material ten meters in length. Actually, the origin of the rings is not completely understood, and they may be due to either a destroyed moon or to leftover material from when Saturn was formed.