Adorned with thousands of beautiful ringlets, Saturn is unique among the planets. It is not the only planet to have rings – made of chunks of ice and rock – but none are as spectacular or as complicated as Saturn's.
Like fellow gas giant Jupiter, Saturn is a massive ball made mostly of hydrogen and helium.
Since ancient times Saturn was known to humanity because of its brightness and closeness to Earth. It’s not possible to give someone credit for the discovery of Saturn, however, the first telescopic observation was conducted by Galileo Galilei in 1610.
Because of the crude telescope available at the time, Galileo failed to observe the rings of Saturn. The discovery of the rings was made by Christiaan Huygens in 1659.
Saturn is named after the Roman god of harvest and time, the equivalent of the Greek god of time, Cronos.
Out of the five visible planets (Mercury, Venus, Mars, Jupiter), Saturn is the most distant from Earth, at a distance of 10.6 AU and an average of 9.6 AU away from the Sun. Light takes approximately 1 hour and 29 minutes to travel from Saturn and then arrive at us. For an actual and accurate position of Saturn, you can check it up online, as the planet is constantly tracked.
Saturn is the second-largest planet of the Solar System, second only to Jupiter, having a radius of 58.232 km or 36.183 mi, about nine times that of Earth.
It has a diameter of 120.536 km or 74.897 mi, almost 9.5 times bigger than the diameter of Earth and a surface area about 83 times greater.
Though it doesn’t have a solid surface, being enveloped in swirling gases and liquids deeper down, it is believed that Saturn has a core much smaller than Jupiter, almost twice the size of Earth – comprised mostly of metals like iron and nickel surrounded by rocky material, and other compounds, solidified by the intense pressure and heat.
Saturn formed together with the rest of the solar system about 4.5 billion years ago. Gravity pulled swirling gas and dust together and thus the gas giant was created. About 4 billion years ago, Saturn settled into its current position in the outer solar system. Like Jupiter, Saturn is mostly made of hydrogen and helium, the same two main components that make up the Sun.
Predominately composed out of hydrogen and helium, Saturn’s density is the lowest out of all the planets in the Solar System, having no true surface just like Jupiter, Uranus, and Neptune.
It does have a dense core in the center, composed out of water, ice, and rocky materials, but no actual landmass. The core is believed to be similar to that of Jupiter – rocky, enveloped by a liquid metallic hydrogen layer and a molecular hydrogen layer with traces of various ices.
The interior is very hot at the core – 12.000 K / 11,700 °C – and it radiates 2.5 times the amount of energy it produces into space than it receives from the Sun. It is estimated that the core’s mass is about 9-22 times bigger than that of Earth. This would result in a diameter of 25.000 km/15.534 mi or almost two times the size of Earth.
The thick liquid metallic hydrogen layer followed by a liquid layer of helium-saturated molecular hydrogen gradually transitions to a gas with increasing altitude. The outermost layer spans 1,000 km / 621 mi and consists of gas.
Covered with clouds that appear as faint stripes, jet streams and storms, Saturn’s upper atmosphere is characterized by winds that can reach up to 1,600 feet / 500 meters per second.
The atmosphere’s pressure is strong enough that it squeezes gas into liquid. The temperature of Saturn’s upper atmosphere is on average about -175C (-285F), quite cold for a gas giant, while below the clouds it gets considerably hotter.
The atmosphere is composed of ammonia, ammonia hydrosulfide, and water that influence the planet's colorful appearance of a brownish-yellow. The outer atmosphere of Saturn contains 96.3% molecular hydrogen and 3.25% helium by volume.
The Great White Spot of Saturn is comprised of many periodic storms large enough to be seen from Earth through a telescope. They are several kilometers wide and encircle the planet, occurring once roughly every Saturnian year - every 30 Earth years. It is predicted that the Great White Spot will occur again in 2020 during the northern hemisphere summer solstice.
Thermography has shown that Saturn's South Pole has a warm polar vortex, the only known example of such a phenomenon in the Solar System. Whereas temperatures on Saturn are normally −185 °C, temperatures on the vortex often reach as high as −122 °C, suspected to be the warmest spot on Saturn.
Saturn is now the “king of the moons” in the Solar System, having a total of 82 confirmed and diverse satellites that range from a couple of meters to several hundred kilometers.
The orbits of these 82 moons have been confirmed as not being embedded in its rings. Only 13 of these satellites have diameters greater than 50 km/31 mi - as well as dense rings that contain millions of embedded moonlets and innumerable smaller ring particles. Only 7 of these moons are large enough to have collapsed into a relaxed, ellipsoidal shape, though only one or two, Titan and possibly Rhea, are currently in hydrostatic equilibrium. Momentarily, not all the moons have been named.
The moons of Saturn also play a role in the planet's ring system. The ring system of Saturn is the largest and most complex in the entire Solar System. They are made out of ice and rock remnants from comets, asteroids, and moons.
These particles range in size from being as small as dust to as big as houses, or even mountains. The ring system is divided into 7 groups of rings: D Ring, C Ring, B Ring, A Ring, F Ring, G Ring, and E Ring.
Together, they are as wide as 4.5 Earths but only about two-thirds of a mile thick. The rings can extend up to 282.000 km / 175.000 mi from the planet. They stay intact and on track because of Saturn’s smallest moons. These shepherding moons orbit between the rings and use their gravity to shape the ring material into circular paths.
Saturn rotates quite quickly on its axis, completing a rotation or day in about 10.6 hours. However, its orbit around the Sun is slow, completing one trip around the Sun or a year, in about 29.5 Earth years.
It is the most oblate planet in the Solar System, with its equatorial diameter of 120.536 km / 74.897 mi, being greater than the planet's polar diameter of 108,728 km / 67.560 mi. If viewed from a small telescope it appears flattened.
Saturn has the lowest density of all the planets - 687 kg/m³ - or in other words, it is lighter than water thus if placed on water, it would float.