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Spitzer discovers ring in Phoebe's orbit around Saturn
Spitzer discovers ring in Phoebe's orbit around Saturn In February 2009, the Spitzer Space Telescope pointed at Saturn and discovered a huge ring associated with the distant, irregular satellite Phoebe. Phoebe, at 107 kilometers across, is likely a captured body; it has a retrograde orbit around Saturn. Material blasted off of Phoebe by impacts of smaller bodies remains in Phoebe's neighborhood for millions to billions of years. Some of it spirals in toward Saturn and is swept up by Iapetus, Titan, and Hyperion. NASA / JPL-Caltech / SSI