270,000 kilometres in diameter yet no thicker than 100 meters, Saturn's ring system must rank amongst the most spectacular phenomena in the solar system. Many things are still unknown about them, and an understanding of their dynamics and evolution has implications for the origin of the solar system itself.
First observed by Galilio in 1610 when he pointed the telescope to the heavens. He understood them to be handles or large moons on either side of the planet. Viewed from Earth they move in such a way that every 15 years they will be side on to earth and therefore disappear, known as the ring plane crossing. Galilio observed this in 1612 and wrote "I do not know what to say in a case so surprising, so unlooked for and so novel"
It wasn't until 1856 that our very own James Clerk Maxwell realised they were not solid rings, but made up of “an indefinite number of unconnected particles”.
The rings have been given letter names in the order of their discovery, only A, B and C rings and the Enke gap can be viewed from Earth. It wasn’t until Voyager flew past in 1980 that the others were identified.
Still not fully understood it is thought that the majority of them are plain old water ice, countless unconnected particles, ranging in size from nearly invisible dust to icebergs the size of a house.
Particles can be cleared from a region to form the divisions by the gravitational effects of a moon about 10 kilometres in size, such a moon was found within the Encke gap.
Large dark shadows, now termed spokes, have been viewed moving across the B ring, these are thought to be clouds of smaller grains acquiring electrical charges and interacting with the magnetic field.
In 2004 the Cassini probe will approach Saturn, it is expected to reveal many more of Saturn's secrets.
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