New data from the orbiting international Cassini spacecraft suggest Saturn's rings existed as far back as 4.5 billion years ago, roughly the same time the sun and planets formed. The probe also found evidence that ring particles are constantly shattering and regrouping to form new rings.

"Recycling allows the rings to be as old as the solar system although continually changing," said a Cassini scientist from the University of Colorado.

Scientists are interested in the rings because they are a model of the disk of gas and dust that initially enveloped the sun and studying them could yield clues about planet formation.

Saturn's ring system consists of seven major rings and thousands of ringlets, mostly made of orbiting ice mixed with dust and rock fragments.

The Cassini mission, funded by NASA and the European and Italian space agencies, was launched in 1997 and reached Saturn in 2004.
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