Saturn
Saturn is the second largest planet in the Solar System, easily recognisable by its rings.
Geography
Keywords
Saturn, rings of Saturn, Solar System, gas giant, outer planet, Mimas, Enceladus, Tethys, Dione, Rhea, Titan, Iapetus, Sun, planet, moon, astronomy, geography
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Solar System
- Sun
- Mercury
- Venus
- Earth
- Mars
- Jupiter
- Saturn
- Uranus
- Neptune
Saturn is the second largest planet in the Solar System, a spectacular outer planet. It is a gas giant (or Jovian planet). Saturn is the most oblate planet, because of its high speed of rotation and low density. It is the least dense planet in the Solar System, the only one with a density less than that of water (0.69 g/cm³ or 0.025 lb/in³).

Saturn
- axis of rotation
- line perpendicular to the orbital plane
- orbital plane of Saturn
- orbit of Saturn
- equator of Saturn
- 26.7°
- rings of Saturn
Data:
Diameter: 120,536 km (74,900 mi or 9.45 Earths)
Mass: 5.6846×10²⁶ kg (1.25×10²⁷ lb or 95.2 Earths)
Average density: 0.69 g/cm³ (0.025 lb/in³)
Surface gravity: 1.065 g
Surface temperature: -180 °C (-292 °F)
Number of moons: 62
Rotation period: 10 h 48 m
Axial tilt: 26.7°
Average distance from the Sun:
1,433,530,000 km = 891,000,000 mi = 9.58 AU = 79.7 light minutes
Orbital eccentricity: 0.054
Orbital period: 29.46 years

Mimas
Mimas:
average distance from Saturn:
185,600 km (115,300 mi)
diameter: 397 km (247 mi)

Enceladus
Enceladus:
average distance from Saturn:
238,100 km (147,900 mi)
diameter: 504 km (312 mi)

Tethys
Tethys:
average distance from Saturn:
294,600 km (183,100 mi)
diameter: 1,060 km (659 mi)

Dione
Dione:
average distance from Saturn:
377,400 km (234,500 mi)
diameter: 1,122 km (697 mi)

Rhea
Rhea:
average distance from Saturn:
527,100 km (327,500 mi)
diameter: 1,528 km (950 mi)

Titan
Titan:
average distance from Saturn:
1,221,900 km (759,300 mi)
diameter: 5,150 km (3,200 mi)

Iapetus
Iapetus:
average distance from Saturn:
3,560,800 km (2,213,000 mi)
diameter: 1,470 km (913 mi)

Section of Saturn
- atmosphere - That of Saturn is about 1,000 km (621 mi) thick. It consists of molecular hydrogen gas. The atmosphere is organized in fast flowing and whirling belts.
- layer of liquid helium and hydrogen - The hydrogen is constantly transforming from gas into liquid state.
- layer of metallic hydrogen - The core is surrounded by a layer of metallic hydrogen.
- core - It probably has a solid inner core containing iron, nickel and silicates with a mass of 9–22 Earth masses.

Orbit of Saturn
- Saturn
- Sun
- average distance from the Sun: 1,433,530,000 km (891,000,000 mi)
- orbital period: 29.46 years
- the orbit of the Saturn

Animation
- Sun
- Mercury
- Venus
- Earth
- Mars
- Jupiter
- Saturn
- Uranus
- Neptune
- axis of rotation
- line perpendicular to the orbital plane
- orbital plane of Saturn
- orbit of Saturn
- equator of Saturn
- 26.7°
- rings of Saturn
- atmosphere - That of Saturn is about 1,000 km (621 mi) thick. It consists of molecular hydrogen gas. The atmosphere is organized in fast flowing and whirling belts.
- layer of liquid helium and hydrogen - The hydrogen is constantly transforming from gas into liquid state.
- layer of metallic hydrogen - The core is surrounded by a layer of metallic hydrogen.
- core - It probably has a solid inner core containing iron, nickel and silicates with a mass of 9–22 Earth masses.
- Saturn
- Sun
- average distance from the Sun: 1,433,530,000 km (891,000,000 mi)
- orbital period: 29.46 years
- the orbit of the Saturn

Ring system
- Colombo Gap
- Maxwell Gap
- Huygens Gap
- Encke Gap
- Keeler Gap
- D Ring
- C Ring
- B Ring
- Cassini Division
- A Ring
- F Ring

Moons of Saturn
- Mimas - – average distance from Saturn: 185,600 km – diameter: 397 km
- Enceladus - – average distance from Saturn: 238,100 km – diameter: 504 km
- Tethys - – average distance from Saturn: 294,600 km – diameter: 1,060 km
- Dione - – average distance from Saturn: 377,400 km – diameter: 1,122 km
- Rhea - – average distance from Saturn: 527,100 km – diameter: 1,528 km
- Titan - – average distance from Saturn: 1,221,900 km – diameter: 5,150 km
- Iapetus - – average distance from Saturn: 3,560,800 km – diameter: 1,470 km
Narration
Saturn is the sixth planet from the Sun, the second largest planet in the Solar System. It was named after one of the oldest of the Roman gods. Saturn was the god of sowing and seeds, the symbol of relentless time. He was identified with the titan Kronos in Greek mythology.
Saturn is the farthest planet that is visible to the naked eye.
The oval shape was first observed by Galileo Galilei with his primitive telescope, but he could not see the ring which caused it.
It was Christiaan Huygens, who first suggested that Saturn was surrounded by a ring. In 1675, Giovanni Domenico Cassini determined that this ring was actually composed of multiple smaller rings with gaps between them; the largest of these gaps was later named the Cassini division.
Saturn was first visited by Pioneer 11 in September 1979. In November 1980, the Voyager 1 spacecraft arrived at the Saturn system. It sent back the first high-resolution images of the planet, its rings and its moons. For the first time, we were able to study clear pictures of the surface features.
Almost a year later, in August 1981, Voyager continued to study this system. On July 1, 2004, the Cassini space probe entered into orbit around Saturn, and provided a great deal of new information about the planet and its moons.
In early 2005, the Huygens probe was detached from Cassini and descended through the nitrogen atmosphere onto the surface of the moon Titan, where it found methane and ethane lakes.
Saturn is the second largest planet in the Solar System, a spectacular outer planet. It is a gas giant, that is, a Jovian, or Jupiter-like planet. It is also the most oblate or flattened planet, because of its high speed of rotation and low density. It is the least dense planet in the Solar System, the only one with a density less than that of water (0.69 g/cm³ or 0.025 lb/in³).
The internal structure of Saturn is similar to that of Jupiter, with a rocky core in the center, a layer of liquid metallic hydrogen surrounding it and a layer of molecular hydrogen outside.
It has an atmosphere of mostly hydrogen, organized in fast flowing and whirling belts.
The winds on Saturn are among the fastest in the Solar System. According to data provided by Voyager, they can move as fast as 400 m/s (895 mph). Saturn's atmosphere has a banded structure similar to Jupiter's, but Saturn's bands are much fainter and much wider near the equator.
The average temperature is -180°C (-292 °F). The internal temperature of Saturn at the core is 12,000 K (21,140 °F). The planet radiates more energy into space than it receives from the Sun; the reason for this is not yet known.
Saturn's magnetic field is strong. The magnetic axis is aligned with the axis of rotation. Some photos from the Hubble space telescope show aurorae.
Saturn is mainly known for its ring system, one of the most spectacular objects in the Solar System. The rings can be observed with a small telescope. The rings are composed of rock and ice particles, ranging in size from speckles of dust to car-sized rocks.
The rings are so spectacular to the eye because of the high albedo of the ice in them. There are dozens of moons orbiting in the gaps between the hundreds of rings; it is the gravity of these moons that holds the rings together and thus they are called shepherd moons.
Saturn has 62 known moons. Only seven of these are large enough to be spherical (a spherical shape is only formed above a certain size and mass limit, due to gravity and internal heat).
The only large moon is Titan, discovered in 1655. Its orbital period is 16 days. The moons are made up of a great deal of water ice.
Cryovulcanism, water vapor erupting from below the surface, was observed on Enceladus, close to Saturn. Most of Saturn's moons only have a diameter of 4–8 km (2.5–5 mi).
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