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Graceful Lanes of Ice

Photojournal: PIA07631
The Cassini Division within Saturn's rings is visible through backyard telescopes on Earth as a dark, seemingly empty region. The division actually contains a great deal of structure, as seen in this color image from the Cassini spacecraft.
The sharp inner boundary of the division (at left of center) is the outer edge of the massive B ring and is maintained by the gravitational influence of the moon Mimas.
Credit
NASA/JPL/Space Science Institute