Ancient civilizations gave us the names of planets in our solar system. But as modern scientists have zoomed in on these bodies and their moons, they have needed to find names for ever more features on their surfaces. Following the tradition of naming planets after Greek and Roman deities, most place names in the solar system are derived from mythology. Thus, mountains, craters, valleys, and other geologic features on Venus come from names for sky goddesses, water goddesses, desert goddesses, war goddesses, or goddesses of love, fate, fortune, and fertility. But sometimes it seems that astronomers get a little tired of always asking their mythology friends for new pantheons to mine for names. Scientists are, after all, just as geeky as any other nerd subculture and they like to stamp the solar system with lesser-known minutiae from their favorite books or devote a crater to a scientific hero. For instance, on Nov. 13 the International Astronomical Union (IAU) approved the name Mount Doom for a peak on Saturn’s moon Titan. According to the Lord of the Rings series, this mountain lies at the heart of Mordor and is the only site where the One Ring can be unmade. Titan is like a geek heaven, with place names coming from both J. R. R. Tolkien’s mythos and Frank Herbert’s Dune series. To come up with such names, members of an IAU task group agree on a theme — let’s say, naming all the craters on Jupiter’s moon Europa after Celtic gods and heroes – and label any known features. As better maps are made of a planet or moon, other people may suggest a name for newly resolved features. The names are reviewed, objected to, debated, and eventually approved and published online. The process isn’t just for scientists; members of the public can submit suggestions as well. Maybe it’s time to start stamping the solar system with places like Westeros and Oz? While we can’t visit these features in person, many have been mapped by our robotic probes. Here we take a look at some images of the geekiest places in the solar system. Above: Titan, King of the Geeks The themes for most of Titan’s features follow the standard mythological criterion. Above you can see the enormous Xanadu region, the bright area just below and to the right of center. Xanadu is named after a legendary palace in Samuel Taylor Coleridge’s poem Kubla Khan. But all mountains on Titan are named for fictional mountains in the Lord of the Rings series, while all plains and labyrinth-like features are named for planets in the Dune series. Image: NASA/JPL/Space Science Institute

Mount Doom All mountains on Titan are named for fictional peaks in Tolkien’s books. In addition to Mount Doom, there is Mount Erebor, the Lonely Mountain, where Bilbo and company travel to fight the dragon Smaug in The Hobbit. Classic rock geeks will also recognize Titan’s Misty Mountains (where the spirits go) which house the Dwarven city of Khazad-dum and the mines of Moria, where the dwarves dug too deep, unleashing the Balrog that — spoiler alert — kills Gandalf. Planets in Frank Herbert’s Dune series provides names for plains on Titan, such as Arrakis Planitia, named for the planet where Paul Atreides becomes Muad’Dib and learns to ride the mighty sandworms. The Chusuk plain and Sikun labyrinth are also named for planets in the Dune series. Images: NASA/JPL-Caltech/Space Science Institute

Scientists in the Solar System Uber-geek Albert Einstein scores his own crater on the moon for his world-changing Theory of Relativity. Plenty of other revolutionary men and women are honored in this way, including Galileo Galilei, champion Renaissance scientist who uncovered evidence that the Earth goes around the sun among other breakthroughs, and Charles Babbage, who invented the first programmable computer back in 1822. Several female scientists lend their names to craters on Venus, including Irene Joliot-Curie, daughter of Marie Curie, and a Nobel laureate herself. Image: LROC/NASA

Lunar Explorers Our closest companion is the moon, whose features people have gazed upon since the dawn of time. It is only recently that scientists have provided some nerdy names to these places; in particular, lunar craters, which are named for scientists, explorers, and astronauts. Just north from the touchdown spot of Apollo 11 are three small craters, named for the first lunar crew, Neil Armstrong, Buzz Aldrin, and Michael Collins. The first man in space, Yuri Gagarin, has also been honored with his own crater. Images: LROC/NASA

Engineers on the Moon The internet’s favorite underdog engineer and mad scientist, Nikola Tesla, lends his name to a crater on the moon. His arch-rival (again, according to the internet) Thomas Edison, gets the same, though their craters are kept far from one another. Nerdy viewers may spot H.G. Wells’ crater near Tesla’s. The British father of science fiction also had a French rival, Jules Verne, who gets a crater, too. Image: LROC/NASA

Artists and Authors Plenty of cultured nerds will find all they need on Mercury, whose craters are named after famous artists, painters, musicians, and authors. There are craters named for Johann Sebastian Bach and Ludwig van Beethoven as well as Charles Dickens and William Faulkner craters. But a true geek will be most thrilled to see the literary luminaries of science-fiction and fantasy get their due, with J. R. R. Tolkien crater on Mercury and Edgar Rice Burroughs crater on Mars. Image: NASA

Valleys of Discovery Astronomical nerds will recognize that all valleys on Mercury are named for radio telescope facilities. But even if you’re not a stargazer, you will know the Arecibo telescope. This spectacular facility, which lends its name to Arecibo Vallis, is a pop-culture staple, featured in the movie Contact, the James Bond film and videogame GoldenEye 007, and even an episode of The X-Files. Image: MESSENGER/NASA

Exploration on Mercury Scarps on Mercury are all named for ships of discovery. So Christopher Columbus’ Santa Maria can be found along with Captain James Cook’s Endeavour. Perhaps the nerdiest place name on Mercury comes from Charles Darwin’s ship The Beagle, which was used to collect evidence for evolution. Image: MESSENGER/NASA