Discovery of Proteus

Proteus is the second-largest moon of Neptune and one of its inner satellites. It was discovered in images taken by the Voyager 2 spacecraft as it approached Neptune in 1989, found by Stephen Synnott and Bradford Smith, even though it is bigger than Nereid, which had been known since 1949, because it orbits so close to the planet that it was lost in Neptune's glare from Earth. Proteus is dark, irregular and heavily cratered, and it is about as large as an object of its type can be without being pulled into a spherical shape by its own gravity. It is named for a sea god of Greek mythology who could change his shape.

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