How to Name the Solar System

Naming the Moons

Not every moon is lucky enough to get a name, especially when it comes to planets like Saturn that have hundreds. Instead, these unlucky orbiting bodies are designated with letters and numbers, such as "S/2004 S 31", which is a satellite, discovered in 2004, around Saturn, and was the 31st such satellite discovered that year. 

Those moons deemed important enough, including planetary moons, dwarf planetary moons, and asteroid moons, will be named usually with some relation to their parent body. However, this isn't always the case, as you'll see below:

1. Mars

   Mars has only two moons: Phobos and Deimos. In classical mythology, these were the twin sons of Ares and Aphrodite, and would accompany their father in his chariot as he rode into battle, representing panic and dread. As its unlikely Mars has more that two moons, we don't have to worry too much about naming conventions here.

2. Jupiter

   Jupiter's moons get their names from lovers, favourites, or descendants of Jupiter or Zeus, who was the king of the gods in Roman and Greek mythology respectively. Additionally, moons orbiting with the planet's rotation (prograde) have names ending with an "a" or "o", and those orbiting in the opposite direction (retrograde) end with an "e".

3. Saturn

   The first moons of Saturn were named after the brothers and sisters of the titan Cronus, with the largest simply being named Titan. Astronomers, however, quickly ran out of siblings, and so moved on to other related characters from Greek and Roman mythology, as well as giants from elsewhere, including Inuit, Gallic, and Norse mythologies.

4. Uranus

   Unlike the other planets, Uranus' moons do not get their names from mythology. Instead, they are named after characters from Alexander Pope's The Rape of the Lock, as well as characters from several plays by William Shakespeare, including A Midsummer's Night Dream, The Tempest, and Much Ado About Nothing.

5. Neptune

   As Neptune is the Roman god of the sea, it makes sense that Neptune's moons would be named for other Greek and Roman gods associated with water, as well as mythical creatures associated with the sea. Similar to Jupiter, prograde moons generally end with an "a", retrograde moons end with an "e", and highly inclined moons end with an "o"

6. Pluto

   Pluto has five known moons, all of which are named after figures from Greek and Roman mythology associated with the underworld, which was the domain that the god Pluto ruled over. It is surely just a coincidence that the largest moon, Charon, just so happens to sound pretty similar to Charlene, the wife of Charon's discoverer.

Surface Features

We have sent spacecraft to many places in the Solar System, and so we have obtained high-resolution imagery of features on the surfaces of planets and moons. Below are some examples of how certain surface features found on planets and moons get their names:

1. Craters on Mercury

   Craters on Mercury must be named after artists, writers, and composers that were famous for more than 50 years and have been dead for more than three years.

2. Features on Venus

   Surface features on Venus are mostly named after historical and mythological women, including Aphrodite Terra, Atalanta Planitia, and Artemis Corona.

3. Lunar Craters

   Lunar craters are named after influential scientists, scholars, artists, and explorers. These include the astronauts who died in the Challenger disaster.

4. Volcanoes on Io

   Volcanoes on Io are named for fire and thunder deities, including Prometheus who gave humans fire in Greek mythology, and Surtr, a leader of the fire giants of Norse mythology.

5. Hills on Titan

   Colles, or hills, on Titan, are named for characters in JRR Tolkien's Middle-earth novels, including Bilbo and Gandalf. Titan's mountains are also named after Middle-earth's mountains.

6. Features on Pluto

   Features on Pluto reference underworld mythology, explorers, and space missions, such as Tombaugh Regio, Cthulhu Macula and Sputnik Planitia.