![]() | |
| Home. | Universe Galaxies And Stars Archives. |  | |
![]() | |
![]() | |
![]() | |
| Universe | Big Bang | Galaxies | Stars | Solar System | Planets | Hubble Telescope | NASA | Search Engine | | |
![]() | |
Saturn the sixth planet in our solar system has 56 confirmed moons in orbit around it. |
![]() ![]() ![]() ![]() ![]() ![]() ![]() | Saturn moons number 56 confirmed, and 3 additional un-confirmed, hypothetical moons. However, a precise number of Saturn's 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. ![]() Saturn's rings cut across an eerie scene that is ruled by Titan's luminous crescent and globe-encircling haze, broken by the small moon Enceladus, whose icy jets are dimly visible at its south pole. North is up. Before the advent of telescopic photography, eight moons of Saturn were discovered by direct observation using an optical telescope:
The use of long-exposure photographic plates made it possible to discover additional moons:
The study of the outer planets has since been revolutionized, first by the use of unmanned space probes, and then by advances in telescopy:
The spurious satellite Chiron, "discovered" in 1861, is now known not to exist. Themis, "discovered" in 1905, also was later proven not to 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: light grey for prograde satellites, darker grey for retrograde satellites.
Grouping the moons of Saturn. ![]() The Saturn System (photographic montage). Although the borders may be somewhat nebulous, Saturn's moons can be divided into eight groups. The Saturn ring shepherds. shepherd satellites are moons that orbit within, or just beyond, a planet's ring system. They have the effect of sculpting the rings: giving them sharp edges, and creating gaps between them. Saturn's shepherd moons are Pan, 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 of Saturn. Janus and Epimetheus are co-orbital moons. 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 of Saturn. 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 of Saturn. Trojan moons 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 points, 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. Irregular satellites of Saturn. ![]() Irregular satellites of Saturn. The Inuit group of Saturn's moons. The Inuit group are five prograde 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 of Saturn's moons. The Norse group are 18 retrograde outer moons that are similar enough in their distance from Saturn to be considered a group. They are Phoebe, Skathi, Narvi, Mundilfari, Suttungr, Thrymr, Ymir, S/2004 S 7 through S/2004 S 10, S/2004 S 12 through S/2004 S 19, and S/2006 S 1 through S/2006 S 8. All of these moons orbit Saturn in a retrograde direction. The Gallic group of Saturn's moons. The Gallic group are three prograde 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. The diagram illustrates the orbits of the irregular satellites of Saturn discovered so far1. The eccentricity of the orbits is represented by the segments (extending from the pericentre to the apocentre) with the inclination represented on Y axis. The satellites above the axis are prograde, the satellites beneath are retrograde. The X axis is labelled in Gm (milion km) and the fraction of the Hill sphere's (gravitational influence) radius (~65 Gm for Saturn). Prograde groups: Inuit and Gallic and the retrograde Norse group are clearly identifiable (from top to bottom). 1Named satellites are plotted in yellow; the unnamed satellites S/2004 Sxx (announced in 2005 and 2006) are plotted in white and S/2006 Sxx in grey. Naming notes of Saturn's moons. Some asteroids share the same names as moons of Saturn: 55 Pandora, 106 Dione, 577 Rhea, 1809 Prometheus, 1810 Epimetheus, 4450 Pan. See also Name conflicts of solar system bodies. Go To Print Article |
![]() |
Universe - Galaxies and Stars: Links and Contacts |
![]() |
![]() |
![]() |
| GNU License | Contact | Copyright | WebMaster | Terms | Disclaimer | Top Of Page. | |
![]() |
![]() |