Saturn is the planet with the highest number of natural satellites in the Solar System, with 82 moons. Find out more about each one of them.
Saturn’s first moon was discovered in 1655. Over the next 200 years, another seven were spotted by scientists, and in 1997 astronomers found 18 new moons in the planet’s orbit.
NASA’s Cassini mission was responsible for finding the rest of the moons we knew until mid-2019, when astronomers using the Subaru Telescope discovered 20 additional moons.
|Position||Name||Distance (km)||Diameter (km)||Discovery|
|2||Daphnis||136000||6 – 8||2005|
|30||S/2007 S 2||16560000||6||2007|
|36||S/2004 S 13||18056000||6||2004|
|42||S/2006 S 1||18930000||6||2006|
|43||S/2004 S 17||19099000||4||2004|
|48||S/2004 S 12||19905000||5||2004|
|52||S/2007 S 3||20518000||5||2007|
|54||S/2004 S 7||20576000||6||2004|
|55||S/2006 S 3||21076000||6||2006|
|–||S/2004 S 37||15892000||4||2019|
|–||S/2004 S 29||16981000||4||2019|
|–||S/2004 S 31||17568000||4||2019|
|–||S/2004 S 20||19418000||4||2019|
|–||S/2004 S 27||19976000||6||2019|
|–||S/2004 S 22||20636000||3||2019|
|–||S/2004 S 30||20821000||3||2019|
|–||S/2004 S 23||21163000||4||2019|
|–||S/2004 S 25||21174000||4||2019|
|–||S/2004 S 32||21214000||4||2019|
|–||S/2004 S 38||21908000||4||2019|
|–||S/2004 S 28||22020000||4||2019|
|–||S/2004 S 35||22412000||6||2019|
|–||S/2004 S 21||22645000||3||2019|
|–||S/2004 S 24||22901000||3||2019|
|–||S/2004 S 36||23192000||3||2019|
|–||S/2004 S 39||23575000||3||2019|
|–||S/2004 S 33||24168000||4||2019|
|–||S/2004 S 34||24299000||3||2019|
|–||S/2004 S 26||26676000||4||2019|
Saturn’s most important moons
Saturn’s largest moon is the second largest in the Solar System, second only to Ganymede, Jupiter’s moon.
It is the only moon in our system known to have an atmosphere that basically consists of nitrogen. This fact makes it a prime candidate for life outside of Earth.
Titan is bigger than the planet Mercury. This giant moon also has clouds, rain, rivers, and lakes of liquid hydrocarbons like Methane and Ethane.
An astronaut could walk on Titan’s surface without a pressure suit, he would only need an oxygen mask and protection against the average temperature of minus 179 degrees Celsius.
This fascinating icy moon is important to Saturn. Enceladus has more than 100 geysers at its south pole. These geysers function as jets that release water vapor and ice particles from an underground ocean.
The particles launched by Enceladus travel at about 400 meters per second and form a cloud that extends for kilometers into space. Part of this material falls on the moon again and another forms Saturn’s E ring.
Also known as the Yin-Yang of Saturn’s moons, Iapetus has a dark-as-coal hemisphere and an extremely bright hemisphere. This contrast fascinated astronomers for many years.
Iapetus is the third largest Saturn’s moon, with an average radius of 736 kilometers (457 miles). This moon is believed to be formed by three-quarters of ice and a quarter of rock.
Saturn’s second largest moon contains something extraordinary: a very thin atmosphere made up of oxygen and carbon dioxide.
In 2010, NASA’s Cassini probe collected oxygen from Rhea’s atmosphere as it passed at an altitude of 97km (60 miles). This was the first time that a spacecraft has collected oxygen molecules from an object outside the Earth.
Rhea has many craters and is made up of ice, with mixed traces of rock, much like a dirty snowball.
Observing the images of Tethys we notice a huge crater and a great valley. This crater, called Odysseus, is the result of an impact and dominates much of the moon’s western hemisphere.
This natural satellite orbits very close to Saturn and is influenced by the planet’s gravitational pull. Saturn’s heat causes the icy surface of Tethys to melt and fill craters and other signs of impact.
The 20 new Saturn moons discovered in 2019
The discovery of Saturn’s new moons was announced in October 2019 by the International Astronomical Union’s Minor Planet Center. Each moon is about 5 kilometers (3 miles) in diameter.
17 of them orbit in the opposite direction to Saturn’s rotation, something called “retrograde direction”. The most distant of this set of new moons takes more than three years to complete one turn around Saturn.
The other 3 follow Saturn’s natural rotation direction, two of which are closer to the planet and take about two years to complete one turn around it.
Considered the most important telescope of Japan’s National Astronomical Observatory, Subaru was responsible for the discovery of Saturn’s 20 new moons. It is located at the Mauna Kea Observatory in Hawaii, on its highest mountain.
Scientists believe that these new discoveries will play a key role in determining how the planets in our Solar System formed and evolved.
The origin of the mythological names of Saturn’s moons
The names of Saturn’s moons are related to the most fascinating characters in Greco-Roman, Norse, and Celtic mythologies.
These associations were suggested by John Herschel in 1847. He proposed the name of the mythological figures associated with the god Saturn that gave the planet its name.
With the discovery of so many new moons, it was suggested in the 20th century that Saturn’s moons should be named after characters from other mythologies.
Titan: In Greek mythology, they were a race of powerful gods who ruled the cosmos during its Golden Age. The Titans were the entities that faced Zeus in his rise to power.
Enceladus: A fire giant created to be Athena’s opponent in the Gigantomachy, a war between the giants and the Olympian gods for control of the cosmos. Despite being the weakest among the giants of Greek mythology, he was the most intelligent.
Iapetus: One of the twelve titans, he was the son of Uranus and Gaia. He was considered the god of time, life and mortality and, in particular, violent death. He was the father of Atlas, Prometheus, Epimetheus, and Menoetius.
Rhea: She was a Titaness in Greek mythology, the wife and sister of Cronus. She is the mother of the Olympian gods. An oracle predicted that Cronus would be defeated by one of his sons, so he began to devour them all. Zeus, however, was hidden by Rhea on the island of Crete.
Tethys: Daughter of Uranus and Gaia, the Titaness was wife and sister of Oceanus. Together, they had three thousand Oceanids (daughters) and numerous river gods (sons) as children.
Erriapus: Giant in Celtic mythology, he is the equivalent of the Roman god Mercury. A portrait of his head was found in the south of France, in the Garonne region.
Janus: Roman god of transitions, he is represented with two faces. Also associated with entrances and exits, he symbolizes the past and the future.
Epimetheus: Son of the titan Iapetus and the Oceanid Asia, he was the husband of Pandora, the woman who opened a box that released evil in the world. From this disaster, they generated Pirra.
Telesto: In Greek mythology, she was an Oceanid, daughter of Oceanus and Tethys. She was associated with divine blessings and success.
Prometheus: In the classic history of Greek mythology, Prometheus was a titan, son of Iapetus, who stole the fire from the gods and gave it to humanity. This was punished by Zeus, who chained him. Every day an eagle came to eat Prometheus’ liver, which was regenerated the next day.
Mundilfari: In Norse mythology, he was the father of Sól and Máni, the gods of the Sun and the Moon. In the story, it is said that Mundilfari thought his children were as beautiful as the Sun and the Moon, and that is why he baptized them with these names.
This attitude offended the gods of the Aesir pantheon (the main pantheon in Norse mythology), who sent Mundilfari’s children to the sky, forcing them to drive the chariots that pull the Sun and Moon, producing the day-night cycle.
Narfi: He was the son of Loki and Sigyn in Norse mythology. His story is contradictory: some texts say that Narfi was transformed into a wolf by the gods and that he killed his brother Nari. In other versions, these two characters are different names for the same person.
Ymir: First living thing to emerge in Norse mythology. He was an ice giant that slept for ages. His sweat spawned several creatures, demons, goblins, and giants.
Calypso: This nymph in Greek mythology was notorious for her seductive power. She was the daughter of Oceanus and Tethys, therefore an Oceanid. Her most important son was Odysseus, a character in Homer’s Odyssey.
Thrym: King of the ice giants in Norse mythology, Thrym stole Mjölnir, Thor’s hammer. To return it, he asked for Freyja’s hand in marriage.
Thor, however, was the one who put on the wedding dress and pretended to marry King Thrym. At the wedding reception, Thor took the hammer, killed Thrym, his sister, and all the guests.