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Pandora ( ; (ギリシア語:Πανδώρα)) is an inner satellite of Saturn. It was discovered in 1980 from photos taken by the ''Voyager 1'' probe, and was provisionally designated . In late 1985 it was officially named after Pandora from Greek mythology. It is also designated as . Pandora was thought to be an outer shepherd satellite of the F Ring. However, recent studies indicate that it does not play such a role, and that only Prometheus, the inner shepherd, contributes to the confinement of the narrow ring. It is more heavily cratered than nearby Prometheus, and has at least two large craters in diameter. The majority of craters on Pandora are shallow as a result of being filled with debris. Ridges and grooves are also present on moon's surface. The orbit of Pandora appears to be chaotic, as a consequence of a series of four 118:121 mean-motion resonances with Prometheus. The most appreciable changes in their orbits occur approximately every 6.2 years, when the periapsis of Pandora lines up with the apoapsis of Prometheus and the moons approach to within about . Pandora also has a 3:2 mean-motion resonance with Mimas. From its very low density and relatively high albedo, it seems likely that Pandora is a very porous icy body. There is a lot of uncertainty in these values, however, so this remains to be confirmed. == Gallery == File:Pandora - Voyager 2.jpg|''Voyager 2'' image of Pandora (August 1981). File:Pandora_-_PIA07570.jpg|Pandora as seen from the Cassini probe in 2005; the rings of Saturn are in the background. File:Pandora (moon) PIA 12690.png|Cassini captured this close view of Saturn's moon Pandora during the spacecraft's flyby on June 3, 2010. 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Pandora (moon)」の詳細全文を読む スポンサード リンク
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