The Moons of Saturn

The 17 icy bodies that orbit the planet display a surprising range of geological evolution. Many of them show craters more than four billion years old, but one of them has terrain so new that no craters are seen

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TORRENCE V. JOHNSON has an asteroid named after him: 2614 Torrence, a body about one kilometer in diameter. Working at the Jet Propulsion Laboratory in Pasadena, Calif., he has been the project scientist for Galileo since 1977--some three quarters of his career as a planetary scientist. He was a member of the imaging team for Voyager and is now on the imaging team for the Cassini mission to Saturn.

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Scientific American Magazine Vol 246 Issue 1This article was published with the title “The Moons of Saturn” in Scientific American Magazine Vol. 246 No. 1 (), p. 100
doi:10.1038/scientificamerican0182-100

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