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Saturn

The sixth planet from the Sun, known for its stunning ring system composed of ice particles, rock debris, and dust. Saturn is the second-largest planet in the Solar System and is visible to the naked eye under dark skies.

Source: solarsystem.nasa.gov

APODs including "Saturn"

A Great White Spot on Rhea

30/05/2005

A Great White Spot on Rhea
Image Credit: NASA Astronomy Picture of the Day

What caused this great white spot on the surface of Saturn's moon Rhea? The spot was first noticed last year by the robot Cassini spacecraft now orbiting Saturn. Cassini's flyby of Rhea in April imaged in the spot in great detail. Astronomers hypothesize that the light-colored spot is the result of a relatively recent impact on the surface of the icy moon. The impact that likely created the crater also splashed light-colored material from the interior onto the darker surface. Rhea spans 1,500 kilometers across and is the second largest moon of Saturn after Titan. Rhea sports several other light colored surface features that are, as yet, not well understood.