Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2005 October 21
See Explanation.  Clicking on the picture will download
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Credit : Cassini Imaging Team, SSI, JPL, ESA, NASA

Explanation: Orbiting in the plane of Saturn's rings, Dione and the other icy saturnian moons have a perpetual ringside view of the gorgeous gas giant planet. Of course, while passing through the ring plane the Cassini spacecraft also shares their stunning perspective. The rings themselves can be seen slicing across the bottom of this Cassini snapshot. Remarkably thin, the bright rings still cast arcing shadows across the planet's cloud tops. Pale Dione, in the foreground, is about 1,100 kilometers across and orbits over 300,000 kilometers from the visible outer edge of the A ring.

Tomorrow's picture: ring galaxy

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