Saturn is the sixth planet from the Sun and is the second-largest planet in our Solar System. It is unique among its type of planets adorned with a mesmerizing system of icy rings. Compared to other planets containing rings, Saturn has the most complex and spectacular rings of its kind.
Like the other Gas giant planet Jupiter, Saturn is also made of mostly Helium and Hydrogen. Surrounded by more than 60 discovered Moons, Saturn is home to some of the most fascinating landscapes in our Solar System. Methane consisting of jets of water lakes is also present on its moon Titan. Saturn system is consisting a rich source of scientific discoveries, most of it yet to be discovered with hidden mysteries.
The planet is named after the Roman god of agriculture and wealth. In 1610, the Italian astronomer Galileo Galilei discovered Saturn and gazed through it for the first time in history through a telescope. It has been known since ancient times and also is the farthest planet from Earth discovered by the unaided human eyes.
Contents in this article:
Structure and Formation
It is the only planet in our solar system whose average density is less than water. The giant gas planet could float in a bowl of water if such a colossal thing existed. Like Jupiter, Saturn is made mostly of Hydrogen and Helium.
At the centre of the planet, there is a dense core of metals like Nickel and Iron surrounded by rocky material and other compounds solidified by the intense heat and pressure. It is enclosed by liquid metallic hydrogen inside a layer of liquid hydrogen.
The planet was formed about 4.5 billion years ago when gravity pulled swirling gas and dust in to become this gas giant. About 4 billion years ago, Saturn settled into its current position in the outer Solar System. The planet has a hot interior, reaching 11,700 °C at its core, and it radiates 2.5 times more energy into space than it receives from the Sun.
Distance and Size
It is 9 times wider than Earth with a radius of 58,232 kilometres (36,182.7 Miles). To be precise if Earth is the size of a ping pong ball, Saturn would be as big as Football.
Saturn is 9.5 Astronomical units away from the Sun, an average distance of 1.4 Billion Kilometres (886 million miles). One astronomical unit (abbreviated as AU), is the distance from the Sun to Earth. From this distance, it takes sunlight 80 minutes to travel from the Sun to the surface of the planet.
Rotation and Orbit
Saturn’s axis is tilted by 26.73 degrees which is almost similar to Earth’s 23.5 degrees with respect to its orbit around the Sun. Due to its tilt, Saturn also experiences seasons like planet Earth. The visible features on Saturn rotate at different rates depending on latitude and multiple rotation periods have been assigned to various regions such as the planet Jupiter.
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The rotation is observed by astronomers who use three different systems for accurately specifying its orbital rotation. Namely, System I, System II, and System III.
System I: Circumscribes the Equatorial Zone, the North and South Equatorial Belt.
System II: Consists the North & South Polar regions with all other Saturnian latitudes.
System III: Encompasses the planet’s internal rotation rate.
The planet records the second-shortest day in our Solar System. One day on Saturn is 10.7 hours and it takes 29.4 Earth years (10,756 Earth Days) to complete one orbit around the Sun. The above-mentioned Earth years are equal to one Saturnian Year.
Structure and Atmosphere
The planet is mostly made up of swirling gases and liquids deeper down. As a gas giant, it doesn’t have a true surface. The extreme Temperature and Pressure deep inside the planet crush, melt and vaporize spacecraft trying to fly into the planet. Despite consisting mostly of hydrogen and helium, most of its mass is not in the gas phase, because hydrogen becomes a non-ideal liquid when the density is above 0.01 g/cm3, which is reached at a radius containing 99.9% of Saturn’s mass.
The interior can reach up to 11,700 degrees Celsius at its core, it radiates 2.5 times more energy into space than it receives from the Sun. “Rainfalls of diamonds have been suggested to occur within Saturn and on its moon as well as in Jupiter and ice giants Uranus and Neptune”.
Check out our posts on Uranus and Neptune
Saturn has got thick layered clouds that appear as faint storms, stripes, and jet streams. The planet has many different shades of colors, like Brown, Grey, and Yellow. Winds in the equatorial region on this planet in the upper atmosphere can reach up to 1,600 feet per second (500 metres per second). The pressure is so immense that it squeezes gas into a liquid. (When compared to Earth, the strongest hurricane winds maxes out about 360 feet per second (110 meters per second).
In the North Pole of the planet, an interesting atmospheric feature is observed which has a hexagon-shaped jet stream. The six-sided jet stream was first captured by the Voyager-I spacecraft. For in-depth observations and future discoveries, the Cassini spacecraft is being used which closely monitors the planet. Spanning about 30,000 Kilometres (20,000 Miles) across, the hexagon is a wavy jet stream of 322 Kilometres per hour (200 Miles per hour) with a massive, rotating storm at the centre. No other planet in our Solar System has such a remarkable weather feature.
The magnetic field is smaller than Jupiter’s but still 578 times as powerful as Earth’s. The planet’s Magnetosphere consists of the planet itself, its rings, and many of the natural satellites. The region of space in which the behaviour of electrically charged particles is influenced more by Saturn’s magnetic field than by the solar wind.
The Cassini spacecraft observed that at least some of Saturn’s aurorae are like Jupiter’s and are largely unaffected by the solar wind. Aurorae occur when charged particles spiral into a planet’s atmosphere along magnetic field lines. Aurorae occur in the ionosphere when excited electrons (ions) of solar winds collide with stomach of nitrogen and oxygen in the presence of Earth’s magnetic field. While Aurorae are caused by a combination of particles ejected from Saturn’s Moons and the planet’s magnetic field’s rapid rotation rate. Yet these “non-solar” causing aurorae are to be known completely.
Saturn is primarily known for its Rings which makes it visually unique and beautiful too. The rings extend from 6,630 to 120,700 Kilometres (4,120 to 75,000 miles) outward from the planet’s equator and average approximately 20 meters (66 feet) in thickness. The planet’s Rings are assumed to have pieces of Asteroids, Comets or shattered moons that disintegrate before they reach the planet due to Saturn’s extremely powerful gravity.
They are made of billions of small chunks of ice and rock coated with another material such as dust. The rings are mostly made up of ring particles which ranges from tiny dust-sized icy grains to chunks as big as a house. Few particles are found to be the size of Mountains. Each ring of the planet orbits at a different speed around the planet. More interestingly if we look at the rings from the cloud tops of Saturn they mostly appear to be in White colour.
The rings are relatively close to each other (and are named alphabetically in the order they were discovered) with the exception of a gap measuring 4,700 kilometres (2,920 miles) wide called the Cassini Division that separates Rings A and B. The main rings are A, B and C. Rings D, E, F and G are fainter and more recently discovered. Starting at Saturn and moving outward, there is the D ring, C ring, B ring, Cassini Division, A ring, F ring, G ring, and finally, the E ring. On the extreme outer part of the ring there is a very faint Phoebe ring in the orbit of Saturn’s moon Phoebe.
Saturn is known as home to a vast array of intriguing and unique worlds. From crater-riddled phoebe to haze-shrouded surface, each of Saturn’s moons depicts another vital piece of a story surrounding the Saturn system. At present, it has 53 confirmed moons with 29 additional provisional moons awaiting its confirmation and many more yet to be discovered. In addition, there is evidence of dozens to hundreds of moonlets with diameters of 40–500 meters in Saturn’s rings which are not considered to be true moons.
Titan is known as the largest moon, (occurs to have its own atmosphere) comprises more than 90% of the mass in orbit around Saturn which includes its Rings. The planet’s second-largest moon is Rhea which has a tenuous ring system of its own along with a tenuous atmosphere. Many of the other moons are small where-in 14 moons are between 10 and 50 km in diameter and the rest of 34 moons are less than 10 km in diameter.
Expectancy for Life Forms
As of observations and discoveries, Saturn’s environment is not suitable for life forms due to its extreme Temperatures and Pressures and materials that characterize the planet.
Few discoveries suggests that Natural Satellites of Saturn, namely, Titan and Enceladus which are home to internal oceans may have a ray of hope for supporting Human Life Forms. While Saturn being a gas giant, is ruled out for living species to adapt to.