There are 288 discovered natural satellites – or moons, as they are colloquially known – in the Solar system. Most of these are found in the outer gas giants. However, many of these have not received proper names as they were discovered recently and have yet to be confirmed. Only 164 moons have proper names.
Out of those, there are 15 moons whose names start with the letter A. These are all listed in the following table. Below you will also find some additional details about each, including physical characteristics, the original meaning of their names, etc.
| Moon | Planet | Name Meaning |
|---|---|---|
| Adrastea | Jupiter | Goddess of “inevitable fate”. Was in charge of nurturing and protecting Zeus. |
| Aegaeon | Saturn | One of the hekatonkheires, three giants of Greek mythology |
| Aegir | Saturn | Personification of the tranquil seas in Norse mythology |
| Aitne | Jupiter | The personification of mount Etna |
| Albiorix | Saturn | Named after a Gallic giant who was said to be “king of the world” |
| Alvaldi | Saturn | A Jötunn (giant). Father of Thiazzi |
| Amalthea | Jupiter | Foster-mother of Zeus |
| Ananke | Jupiter | Personification of necessity. It also means “constrain” or “force”. |
| Angrboda | Saturn | A female Jötunn (giant) |
| Anthe | Saturn | It means “flowery”. One of the Alkyonides, the seven beatiful daughters of Alkyoneus |
| Aoede | Jupiter | One of the three original muses (goddesses of literature, science, and arts) |
| Arche | Jupiter | One of the muses |
| Ariel | Uranus | Named after a character in Alexander Pope’s works. |
| Atlas | Saturn | One of the Titans. Condemned to hold up the sky for eternity after the Titanomachy |
| Autonoe | Jupiter | Theban princess and eldest daughter of Cadmus. |
Adrastea
A small inner moon of Jupiter, Adrastea was discovered in 1979 using Voyager 2 images. Named after the goddess of “inevitable fate,” it’s one of Jupiter’s smallest moons at about 20 km in diameter. Orbiting closer than Jupiter’s synchronous orbit radius, Adrastea contributes to the planet’s ring system.
Aegaeon
This tiny moon of Saturn, named after a Greek mythological giant, was discovered in 2008. With a diameter of just 500 meters, Aegaeon orbits within Saturn’s G ring and is believed to be a primary source of the ring’s material. It creates gravitational disturbances in the ring, forming “propeller features.”
Aegir
An irregular moon of Saturn discovered in 2004, Aegir is named after the Norse personification of tranquil seas. Part of the Norse group, it orbits Saturn in retrograde with a diameter of about 6 km. Its highly elliptical orbit takes about 1025 days to complete.
Aitne
Discovered in 2001, Aitne is a small, irregular moon of Jupiter named after the personification of Mount Etna. Part of the Carme group, it has an estimated diameter of 3 km and takes about 730 days to orbit Jupiter retrograde.
Albiorix
One of Saturn’s larger irregular moons, Albiorix was discovered in 2000. Named after a Gallic giant meaning “king of the world,” it has a diameter of about 32 km. It belongs to the Gallic group and orbits Saturn every 783 days.
Alvaldi
A moon of Saturn discovered in 2004, Alvaldi is named after a Jötunn (giant) from Norse mythology. Part of the Norse group, it has an estimated diameter of 6 km and orbits Saturn retrograde. Its eccentric orbit suggests it might be a captured object.
Amalthea
Discovered in 1892, Amalthea was the first Jovian moon found after the Galilean moons. Named after Zeus’s foster-mother, it’s Jupiter’s third-largest moon by size at 250 x 146 x 128 km. It completes an orbit in just 12 hours and is known for its red color, likely due to sulfur from Io.
Ananke
This retrograde irregular moon of Jupiter was discovered in 1951. Named after the personification of necessity in Greek mythology, Ananke is the parent body of its own group of moons. It has a diameter of about 30 km and orbits Jupiter every 631 days.
Angrboda
Discovered in 2004, Angrboda is a moon of Saturn named after a female Jötunn from Norse mythology. Part of the Norse group, it has an estimated diameter of 6 km and orbits Saturn retrograde. In mythology, Angrboda was known as the “Bringer of Anguish.”
Anthe
A small inner moon of Saturn discovered in 2007, Anthe’s name means “flowery” in Greek. With a diameter of only 1 km, it orbits within Saturn’s G ring. Anthe is in a 10:11 orbital resonance with Mimas, causing its orbit to vary by about 20 km.
Aoede
Discovered in 2003, Aoede is a retrograde irregular moon of Jupiter named after one of the original Muses. Part of the Pasiphae group, it has an estimated diameter of 4 km and takes about 714 days to orbit Jupiter. In mythology, Aoede was the Muse of song.
Arche
Another retrograde irregular moon of Jupiter, Arche was discovered in 2002. Named after a Muse associated with origins, it belongs to the Carme group. Arche has an estimated diameter of 3 km and orbits Jupiter in approximately 715 days.
Ariel
One of Uranus’s major moons, Ariel was discovered in 1851. Named after a character in works by Pope and Shakespeare, it’s Uranus’s fourth-largest moon at 1158 km in diameter. Ariel has a bright surface composed mainly of water ice and shows evidence of past geological activity.
Atlas
Discovered in 1980 from Voyager 1 images, Atlas is a small inner moon of Saturn named after the Titan who held up the sky. Known for its unique “flying saucer” shape, Atlas has a mean diameter of 30 km. It orbits just outside Saturn’s A Ring, helping maintain its sharp edge.
Autonoe
A retrograde irregular moon of Jupiter discovered in 2001, Autonoe is named after a Theban princess. Part of the Pasiphae group, it has an estimated diameter of 4 km and orbits Jupiter in about 761 days. Its highly inclined orbit suggests it may be a captured object.
Click on a letter below for a list of moons that begin with it.
A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z
Related:
For more on how moons are named check out this article.