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Saturn has 47 confirmed Natural Satellite s. INTRODUCTION Saturn is currently known to have 47 moons, many of which were discovered very recently, and 3 suspected moons. However, a precise number of moons can never be given, as there is no objective dividing line between the anonymous orbiting fragments that form Saturn's ring system and the larger objects that have already been named as moons.
The spurious satellite Themis , "discovered" in 1905 , does not exist. TABLE OF KNOWN MOONS The Saturnian moons are listed here by orbital period, from shortest to longest. Moons massive enough for their surfaces to have Collapsed into a Spheroid are highlighted in light purple. Titan, which is planetary in size, has darker highlighting. The irregular (captured) moons are indicated in grey.
GROUPING THE MOONS Although the borders may be somewhat nebulous, Saturn's moons can be divided into eight groups. The ring shepherds , Daphnis , Atlas , Prometheus , Pandora , S/2004 S 3 , in addition to the unconfirmed moons S/2004 S 4 and S/2004 S 6 . The co-orbitals Janus and Epimetheus are Co-orbital Moon s. These two moons are of roughly equal size and have orbits with only a few kilometers difference in diameter, close enough that they would collide if they attempted to pass each other. Instead of colliding, however, their gravitational interaction causes them to swap orbits every four years. See Epimetheus' Article for a more detailed explanation of this arrangement. The inner large moons The innermost large moons of Saturn orbit within its tenuous E Ring . They are Mimas , Enceladus , Tethys and Dione . Two recently discovered tiny moons also orbit within this group: Methone and Pallene . So too do the co-orbital moons that form a group of their own (see below). The Trojan moons Trojan Moon s are another kind of co-orbitals. Like other co-orbitals, they are a feature unique to the Saturnian system. They are moons that orbit at exactly the same distance from Saturn as another moon, but at such a distance from the other moon that they never collide. Tethys has two tiny co-orbitals Telesto and Calypso , and Dione has also two, Helene and Polydeuces . All four of these moons orbit in the larger moons' Lagrangian Point s, one in each point. The outer large moons Saturn's largest moons all orbit beyond its E Ring and can thus be considered a distinct group. They are Rhea , Hyperion (which is relatively small and very irregular), Titan and Iapetus . The Inuit group The Inuit group are five outer moons that are similar enough in their distances from Saturn and their orbital inclinations that they can be considered a group. They are Kiviuq , Ijiraq , Paaliaq , Siarnaq , and S/2004 S 11 . The Norse group The Norse group are 18 outer moons that are similar enough in their distance from Saturn and their orbital inclination that they can be considered a group. They are Phoebe , Skathi , Narvi , Mundilfari , Suttungr , Thrymr , Ymir , S/2004 S 7 through S/2004 S 10 , and S/2004 S 12 through S/2004 S 18 . All of these moons orbit Saturn in a retrograde direction. The Gallic group The Gallic group are three outer moons that are similar enough in their distance from Saturn and their orbital inclination that they can be considered a group. They are Albiorix , Erriapo and Tarvos . NAMING NOTES Some , 106 Dione , 577 Rhea , 1809 Prometheus , 1810 Epimetheus , 4450 Pan . SEE ALSO
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