One Moon in Light, One in Dark

This Cassini image shows Saturn’s shadowy side, its rings, and two of its moons: Mimas and Enceladus. Mimas is on the left, and shows its dark side, while Enceladus is on the far side of the rings, closer to Saturn, and is illuminated by the reflected sunlight from Saturn’s bright side. Cassini took this photo on June 11, 2006 when it was 3.9 million kilometers (2.5 million miles) from Mimas.
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Epimetheus in Saturn’s Glare

Look at this photograph very carefully. Just below Saturn’s rings, to the left of the bright side of the planet is its tiny moon Epimetheus (116 km or 72 miles across). This moon hugs the outside edge of Saturn’s F ring, beyond the orbit of Pandora. Cassini took this photograph on June 9, when it was approximately 4 million kilometers (2.5 million miles) from Epimetheus.
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Secrets Revealed in Saturn’s Faintest Rings

New photos of Saturn’s E ring shows how it has a similar double-banded structure to Jupiter’s ring. Thanks to data gathered by Cassini, scientists now believe that the E ring particles originate from water geysers on Saturn’s moon Enceladus. The double-banded appearance occurs because there are actually less particles at the ring plane than there are above and below it. Scientists believe the double structure is created by the trajectory of particles ejected from Enceladus, or through ongoing interactions between the moon and the ring.
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The Mysteries of Enceladus

NASA’s Cassini spacecraft has been on the hunt for atomic oxygen since it arrived at Saturn. The source turned out to be a thin atmosphere of water vapour surrounding Saturn’s moon Enceladus. Cassini flew past the mysterious moon in July 2005, skimming within 175 kilometres (109) of the surface. It discovered that large dark cracks around its southern pole were warm and spewing out water vapour and ice particles. Cassini is due for a second look in 2008 when it will make another close flyby.
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Cassini’s Mission is Half Over

NASA’s Cassini spacecraft will reach the half-way point of its 4 year mission on Friday – it arrived at Saturn on June 20, 2004. Although the spacecraft has already visited Titan 15 times, it’ll pick up the pace for the remainder of its mission, performing another 30 flybys. Starting in July, mission controllers will begin altering Cassini’s orbit with respect to the Sun by nearly 180-degrees. This will give it a bird’s eye view of Saturn’s ring system.
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Saturn’s Tiny Moon Polydeuces

We’re accustomed to seeing photographs of Saturn’s larger moons, like Titan, Dione and Enceladus. Here’s an image of one of its smallest: newly discovered Polydeuces. This moon is only 3 km (2 miles) across, and shares the same orbit as much larger Dione. Cassini took this photo on May 22, 2006 when it was approximately 73,000 kilometers (45,000 miles) away.
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Enceladus and Janus

This photograph, captured by NASA’s Cassini spacecraft shows Saturn’s moons Enceladus and Janus. Also visible is Saturn’s F ring, including the bright core which is about 50 km wide, and contains many features of its own. Cassini took this photograph on May 21, 2006 when it was approximately 565,000 kilometers (351,000 miles) from Janus and 702,000 kilometers (436,000 miles) from Enceladus.
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