New observations by the Cassini probe in orbit around Saturn have shown far more rock and mud in the inner rings than was previously believed to exist.

Previously believed to comprise of mostly water ice, it is now seen that rock and mud make up a larger portion of the rings composition, more prevalent in the inner rings than the outer rings.

Scientists still don't know how the rings were formed, but one theory is that an icy object was broken up by Saturns gravity and subsequent meteors deposited the darker material, more obvious in the inner rings where water ice is less concentrated.

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