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Monday, November 23, 2009

Photo: Neptune Moon Was Once Passing Planetoid, Study Says


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A composite image depicts Triton (foreground) in orbit around Neptune. Triton has long been thought to be a planetlike object that was caught by Neptune's orbit. A new theory suggests that the unusual moon was one of a pair of such objects, but only Triton was captured by the planet's gravitational pull.

Image courtesy NASA