The seventh planet, Uranus, is named after the Greek primordial deity of the Sky, Ouranos. It was the first planet discovered in the modern era, breaking the historical boundary of the known solar system, which had been fixed at Saturn since antiquity. The Latinized form of the name was chosen to maintain a consistent mythological hierarchy among the planets.
The Historical Discovery and Initial Name Attempt
The planet’s existence was first confirmed on March 13, 1781, by the German-born British astronomer, Sir William Herschel. Herschel initially thought the object was a comet, but calculations soon proved it followed a nearly circular orbit too distant for a typical comet. This established the object as a new planet, doubling the known size of the solar system.
As the discoverer, Herschel chose to honor his patron, King George III of Great Britain, proposing the name “Georgium Sidus,” Latin for “George’s Star.” This proposal was well-received in Britain.
However, the name was largely unpopular outside of Britain. The international astronomical community objected because “Georgium Sidus” abandoned the long-standing tradition of naming planets after figures from Greco-Roman mythology. Other names, such as “Herschel” and “Neptune,” were briefly considered, highlighting the lack of international consensus.
Establishing the Classical Naming Convention
The adoption of the name “Uranus” was championed by the German astronomer Johann Elert Bode. Bode argued that the new planet must adhere to the classical naming convention established for the five visible planets. This tradition required using mythological names to maintain a systematic order in the celestial family.
Bode’s rationale for “Uranus,” the Latin form of the Greek Ouranos, was based on mythological genealogy. The known outer planets were Saturn (Cronus) and Jupiter (Zeus), and Saturn was traditionally considered the father of Jupiter. Therefore, Bode suggested the planet should be named for the father of Saturn, Uranus, in the Romanized Greek tradition.
The name gained gradual acceptance. It did not become universal, however, until 1850, when the British nautical almanac finally dropped “Georgium Sidus” and adopted “Uranus,” making it the official international designation.
Uranus in Greek Mythology
The mythological figure the planet is named after is Ouranos, the primordial Greek deity who personified the Sky itself. Ouranos was born from Gaea, the personification of the Earth, and subsequently became her consort, covering her as the starry sky covers the Earth.
The union of Ouranos and Gaea produced the first generation of divine beings, including the twelve Titans. This lineage includes Cronus, the Greek equivalent of the Roman god Saturn, establishing the father-son relationship that justified the planet’s name. Ouranos is a foundational figure in the Greek pantheon, representing the celestial dome and the earliest divine rule.