Saturn is the second-largest planet in the Sol system, being a gas giant of considerable mass. It has seven largest moons, all icy selenic planetoids (save Titan). Two of these, Titan and Enceladus, have been settled by humans.
Saturn is the sixth planet out from its sun, Sol. It has 64 natural satellites, the largest and most significant of which is Titan. One of its smaller spheroid moons, Enceladus, is essentially the twin of Jupiter's moon Europa: a cryonic world with a life-filled water ocean beneath its glacial crust. Saturn also has numerous human-built artificial satellites (the largest being Opes) in its orbit.
Saturn is primarily composed of hydrogen and helium, with other light elements and gases comprising the rest. It has a core of semi-liquid metallic hydrogen, but as is typical for a gas giant Saturn lacks a solid surface. The outer cronian atmosphere is divided into several faintly visible bands at different latitudes, resulting in turbulence and storms along their boundaries, the largest of which is a giant hexagonal cyclone occupying the north pole of the planet.
Saturn's defining feature is its extensive, breathtaking ring system composed of innumerable tiny fragments of water ice in a circular ring roughly 20 meters thick. This system is divided into twelve rings, half of which are major: in order of distance from Saturn itself, the D, C, B, A, F, G, and E rings. The visible component of the rings is composed of the C, B, A, and F rings, as G and E are only visible in infrared or when backlit by the sun.
AerocoloniesSince Saturn's gravity is only slightly higher than that of Earth, it was the site of the first human "aerocolony"- an enclosed habitat city engineered to rest on the heavier cloud layers and meander across the gaseous surface of the planet according to the whims of the atmospheric currents. Given the success of Project Cirrus, as it was called, the settlement of Groombridge 34's sole gas giant Opal was greenlit.
Flora & Fauna
Orbital CharacteristicsSemi-major axis 9.6 AU Orbital period 10759.22 days Rotation period 10.56 hours Notable satellites
Planetary CharacteristicsClass giant frigid jovian (J) Radius 58232 km Surface area 4.27e+10 km2 Volume 8.27e+14 km3 Mass 5.7e+26 kg Gravity 10.44 m/s2 Atmospheric pressure (cloud layer) 1.38 atm Atmosphere composition
- 98.3% hydrogen
- 3.25% helium
- 0.45% methane
- <0.1% other gases
Footnotes1 These three, as well as other minor moons of Saturn (Atlas, Prometheus, Epimetheus, Hyperion, Phoebe, Fenrir, and Aegir), share names with planets in other star systems. Tethys, Rhea, and Iapetus are exceptions to the IAU rule regarding celestial name-sharing:
Extrasolar planets may take the names of Sol-system asteroids or minor (not spherical) Sol-system moons, but not the names of planets, dwarf planets, or major (spherical) moons in the Sol system.