What do Saturn's rings look like from the dark side? From Earth, we usually see Saturn's rings from the same side of the ring plane that the Sun illuminates them -- one might call this the bright side. Geometrically, in the above picture taken in August by the robot Cassini spacecraft now orbiting Saturn , the Sun is behind the camera but on the other side of the ring plane. Such a vantage point gives a breathtaking view s of the most splendid ring system in the Solar System. Strangely, the rings have similarities to a photographic negative of a front view. For example, the dark band in the middle is actually the normally bright B-ring . The ring brightness as recorded from different angles indicates ring thickness and particle density of ring particles. At the top left of the frame is Saturn's moon Tethys , which although harder to find, contains much more mass than the entire ring system .
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