Moon, Saturn, and Regulus

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For sheer beauty, nothing in the solar system beats the rings of Saturn. Thousands of individual rings encircle the planet, made of bits of ice and rock.

Some recent research indicates that the rings will continue to decorate the solar system for a long time.

For decades, the leading idea has been that the rings formed within the last hundred million years -- perhaps when a small moon was pulled apart by Saturn's gravity, or smacked by a passing comet. In this scenario, the rings are fairly short-lived, so Saturn itself would outlast them by billions of years.

But last year, a team of researchers concluded otherwise.

The team was led by Larry Esposito of the University of Colorado. It studied observations by the Cassini spacecraft, which has been orbiting Saturn since 2004.

The team concluded that the rings contain a lot more material than anyone had thought. The material is continually churned up, with large chunks breaking apart, and smaller ones coming together to form bigger ones. This process makes the rings look much younger than they really are -- like a house that gets a fresh coat of paint. So the rings may be as old as Saturn itself -- and likely to stick around for billions of years more.

Saturn is in great view tonight. It looks like a bright golden star quite near the Moon. It's a little to the upper left of the Moon at nightfall, with the true star Regulus close by. Small telescopes reveal Saturn's glorious rings.

Script by Damond Benningfield, Copyright 2008

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