Cassini Flyby Gives Clues to Origin of Saturn's Moon Phoebe

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The Cassini spacecraft has sent back the clearest pictures ever taken of Phoebe, one of Saturn¿s outer moons. Cassini came within 2,068 kilometers of the dark moon and acquired data using 11 different instruments. "It¿s obvious a lot of new insights into the origin of this strange body will come as a result of all this," notes Cassini Imaging team leader Carolyn Porco of the Space Science Institute in Boulder, Colo.

The last spacecraft visitor to the neighborhood was Voyager 2, which flew within 2.2 million kilometers of Phoebe in 1981. The new images reveal that the icy body has seen its share of hits both large and small: the satellite shows evidence of its combative past in craters ranging in size from 50 kilometers wide to less than a kilometer across. Within the impressive pictures lie clues to Phoebe¿s internal properties, which scientists will use to piece together the moon¿s origin and evolution.

"We might be seeing one of the chunks from the formation of the solar system, 4.5 billion years ago," says Torrence Johnson of NASA¿s Jet Propulsion Laboratory. "It¿s too soon to say. It¿s important to see the big picture from all of the other instruments to get the global view on this tiny moon." Cassini is scheduled to enter into a planned four-year orbit around Saturn on July 1, during which it will travel around the system 76 times and carry out 52 close encounters with seven of the planet¿s 31 known moons.

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