Pluto got its name from an eleven-year-old English schoolgirl named Venetia Burney, who suggested the Roman god of the underworld as a fitting title for the cold, distant world discovered in 1930. Her suggestion traveled from a breakfast table in Oxford to the Lowell Observatory in Arizona, where astronomers voted to adopt it over dozens of competing proposals. The story involves a grandfather’s connections, a transatlantic telegram, and a name so well chosen that it shaped how we talk about the far reaches of the solar system to this day.
The Discovery That Needed a Name
On February 18, 1930, a young astronomer named Clyde Tombaugh spotted a tiny, moving speck on photographic plates taken at the Lowell Observatory in Flagstaff, Arizona. Tombaugh had been hired specifically to search for a hypothetical “Planet X,” whose existence had been predicted by the observatory’s founder, Percival Lowell. Lowell spent the last years of his life hunting for a planet beyond Neptune that he believed was gravitationally tugging on the outer planets’ orbits. He died in 1916 without finding it, but his observatory continued the search.
When Tombaugh confirmed the discovery, the observatory had a problem that might sound trivial but turned out to be surprisingly contentious: what to call the thing. By tradition, planets were named after figures from Greek and Roman mythology. Uranus, Neptune, and the other planets all followed this convention, and there was no reason to break from it. But choosing exactly which mythological figure would represent the new world was another matter entirely. Suggestions poured in from astronomers, classicists, and members of the public around the world. The Lowell Observatory received over a thousand name proposals in the weeks following the announcement.
Venetia Burney’s Breakfast Table Suggestion
On March 14, 1930, Venetia Burney was eating breakfast with her grandfather, Falconer Madan, a retired librarian of the Bodleian Library at the University of Oxford. Madan read aloud from the newspaper about the discovery of the new planet, and Venetia, who had a keen interest in classical mythology, immediately suggested “Pluto.” She later recalled thinking that the god of the dark, cold underworld seemed like a natural match for a world so far from the sun that it must be freezing and dim.
Madan was impressed enough to bring the idea to Herbert Hall Turner, a professor of astronomy at Oxford. Turner liked the suggestion and sent a telegram to colleagues at the Lowell Observatory, proposing the name Pluto. The observatory staff had already been considering several names, but Pluto quickly rose to the top of the list. On May 1, 1930, the name was officially adopted. Venetia reportedly received a five-pound note from her grandfather as a reward, a decent sum for a child in 1930s England.
Venetia Burney lived long enough to see Pluto reclassified as a dwarf planet in 2006. She died in 2009 at the age of ninety. NASA honored her contribution by naming the student-built dust counter aboard the New Horizons spacecraft the “Venetia Burney Student Dust Counter,” a small but fitting tribute to someone whose childhood suggestion became one of the most recognized names in astronomy.
Why “Pluto” Beat the Competition
The name Pluto had several things working in its favor beyond Venetia Burney’s suggestion. First, it followed the established pattern. The planets in the outer solar system were already named after major Roman gods: Jupiter, Saturn, Uranus, and Neptune. Pluto, the Roman god of the underworld (known as Hades in Greek mythology), was one of the few major deities in the Roman pantheon who hadn’t yet been claimed by a celestial body. He was Jupiter’s brother and Neptune’s brother, which gave the name a sense of family continuity.
Second, the name carried poetic resonance. Pluto ruled over a realm of darkness and shadow, a kingdom hidden from the living world. The new planet was the most distant known object in the solar system, lurking in perpetual twilight where the sun would appear as little more than a bright star. The mythological associations felt apt in a way that the competing names did not.
Third, and this detail was not lost on the Lowell Observatory staff, the first two letters of “Pluto” are P and L, the initials of Percival Lowell. Whether this was a deliberate factor in the decision or a happy coincidence depends on which account you read. Some historians of astronomy treat it as a decisive consideration; others view it as a pleasant bonus that helped seal the deal. Either way, the monogram connection made the name especially appealing to the observatory that Lowell had founded and funded.
The Names That Lost
Among the more than a thousand suggestions, a few stood out as serious contenders. Minerva, the Roman goddess of wisdom, was a popular early favorite, but it had already been given to an asteroid. This was a recurring problem: many mythological names that seemed appropriate had been used for the hundreds of asteroids cataloged by that point. Cronus, the Greek titan and father of Zeus, was another proposal, as was Zeus itself. Some people suggested naming the planet after Percival Lowell directly, which the observatory considered but ultimately rejected on the grounds that naming a planet after a modern person would break with centuries of tradition.
Constance Lowell, Percival’s widow, had her own ideas. She initially pushed for the name “Zeus,” then shifted to “Lowell,” and finally proposed “Constance.” None of these gained traction with the astronomical community, and her persistence reportedly created some awkwardness for the observatory staff, who were trying to navigate both scientific convention and the wishes of their founder’s estate.
A few more exotic suggestions included Erebus (the primordial god of darkness), Prometheus, and even the name “Planet X” itself, treated as a permanent designation rather than a placeholder. In the end, Pluto won a vote among the Lowell Observatory staff on May 1, 1930, with the name receiving unanimous support.
The Mythological Figure Behind the Name
Pluto occupies an interesting place in Roman and Greek mythology. In the older Greek tradition, the ruler of the underworld was called Hades, a name that carried grim and fearful associations. Pluto, or Plouton, was originally an epithet meaning “the wealthy one,” referring to the riches buried underground: precious metals, gems, and the fertile soil from which crops grew. Over time, the name Pluto became a more common way to refer to the god, partly because it sounded less forbidding than Hades. The Romans adopted the name Pluto and used it as their standard designation for the god of the dead.
Pluto’s realm was not a place of punishment in the way that the Christian concept of hell later became. It was simply where the dead went, a shadowy kingdom beneath the earth separated from the living world by five rivers, the most famous being the Styx. Souls crossed the Styx on a ferry piloted by Charon, and the entrance to the underworld was guarded by Cerberus, a monstrous multi-headed dog. These mythological details became relevant again decades later when astronomers began discovering moons around the dwarf planet and needed names for them.
Pluto’s Moons and the Underworld Naming Theme
When James Christy discovered Pluto’s largest moon in 1978, he named it Charon after the mythological ferryman. The choice maintained the underworld theme established by the planet’s own name, and it set a precedent. As additional moons were found in the 2000s and 2010s, the International Astronomical Union continued the pattern. Nix (named after Nyx, the Greek goddess of night and mother of Charon) and Hydra (the many-headed serpent guarding an entrance to the underworld) were named in 2006.
The fourth and fifth moons, discovered in 2011 and 2012 respectively, received their names in 2013. The IAU named them Kerberos, after the three-headed dog that guarded the entrance to Pluto’s realm, and Styx, after the river the dead had to cross to reach the underworld.1AmericaSpace. Pluto’s Unnamed Moons Given Names by IAU The spelling “Kerberos” rather than “Cerberus” was chosen because an asteroid already bore the name Cerberus, echoing the same collision problem that had knocked Minerva out of the running for the planet itself back in 1930.
The consistency of the underworld theme across Pluto and all five of its known moons is unusual in planetary science. Other moon systems have naming conventions, but few are as tightly thematic. Jupiter’s moons are named after the god’s various lovers and descendants, which is a broad category. Saturn’s moons draw from multiple mythological traditions. Pluto’s system, by contrast, reads like a cast list for a single mythological story, all because Venetia Burney picked the right god for the right planet.
From Planet to Element
Pluto’s name rippled beyond astronomy. In 1941, just eleven years after the planet’s discovery, chemist Glenn T. Seaborg at the University of California, Berkeley, discovered element 94 and named it plutonium. The choice was deliberate and followed a pattern: the two elements immediately before it in the periodic table were uranium (element 92, named after Uranus) and neptunium (element 93, named after Neptune). Naming element 94 after the next planet out was, as Seaborg put it, “a natural choice.”2Chemical & Engineering News. Discoverers of plutonium and Pluto meet
The planet-to-element pipeline is one of the tidier naming traditions in science. Uranium was discovered in 1789, just eight years after William Herschel found the planet Uranus in 1781. Neptunium was synthesized in 1940, nearly a century after Neptune’s discovery in 1846. Plutonium completed the trio within a decade of Pluto’s discovery. When Pluto was reclassified as a dwarf planet in 2006, some commentators joked that plutonium should be reclassified too, but element 94 retained its name and its place in the periodic table without controversy.
The Disney Question
People regularly ask whether the dwarf planet was named after Mickey Mouse’s cartoon dog or vice versa. The answer is straightforward: the cartoon character was named after the planet, not the other way around. Walt Disney’s Pluto first appeared in a 1930 cartoon called “The Chain Gang” and was given his name later that same year. The planet’s naming in May 1930 preceded the character’s debut, and Disney animator Ben Sharpsteen later confirmed that the dog was named in honor of the newly discovered world. The timing was no coincidence: the discovery of Pluto was headline news throughout 1930, and Disney’s team took advantage of the public’s fascination.
The coincidence of timing has created a persistent folk belief that the naming went the other direction, or that there was some formal connection between the Disney studio and the Lowell Observatory. There wasn’t. The two Plutos share nothing but a name and a year of origin. But the association has arguably helped keep the dwarf planet in popular consciousness in a way that, say, Eris or Makemake have not managed.
How the 2006 Reclassification Affected the Name
When the International Astronomical Union voted in 2006 to reclassify Pluto as a dwarf planet, the decision generated enormous public outcry. People were attached to Pluto in a way they were not attached to, for instance, the classification status of Ceres or Vesta. Part of that attachment was surely about the name itself. “Pluto” is short, punchy, mythologically evocative, and has been embedded in popular culture for nearly a century. It is a name people grew up memorizing in school alongside the other eight planets, and the reclassification felt to many like losing a member of the family.
The name, though, was never in danger. The IAU’s reclassification changed Pluto’s category, not its designation. It remains Pluto in every astronomical catalog, every textbook, and every spacecraft mission plan. In fact, the IAU subsequently decided that objects in Pluto’s class of trans-Neptunian dwarf planets would be called “plutinos” if they shared its orbital resonance pattern with Neptune, further cementing the name’s role as a reference point for an entire category of distant objects. Venetia Burney’s suggestion didn’t just name one world; it ended up anchoring the terminology for a whole population of icy bodies at the edge of the solar system.
Naming Rights in Planetary Science
The story of Pluto’s naming highlights something unusual about how celestial objects get their names. Unlike species in biology, where the discoverer traditionally has naming rights, or chemical elements, where IUPAC follows a structured review process, the naming of planets and major solar system bodies has historically been an informal, sometimes messy affair. In 1930, there was no formal international body governing planetary names. The Lowell Observatory essentially chose the name themselves, and the rest of the astronomical community accepted it.
The IAU formalized naming conventions later in the twentieth century, and today the process is considerably more structured. When New Horizons flew past Pluto in 2015 and revealed mountains, plains, and glaciers on the surface, the IAU approved feature names drawn from the same mythological well that Venetia Burney had tapped. The heart-shaped region informally known as “Pluto’s Heart” was officially named Tombaugh Regio, after Pluto’s discoverer. A dark region near the equator became Cthulhu Macula, borrowing from H.P. Lovecraft’s fictional mythology of the underworld. Other features were named after underworld deities from cultures around the globe, from the Hindu Yama to the Egyptian Anubis, broadening the underworld theme beyond its Greco-Roman origins.
The naming of surface features on Pluto thus became a kind of global survey of how different civilizations imagined the realm of the dead, all because one eleven-year-old in Oxford thought a dark, distant planet deserved the name of the god who ruled in darkness. Few naming decisions in the history of science have proved as generative or as enduring.