Uranus' 'King' and 'Queen' Discovered

#19 Science in History

11 January 1787

On this day in 1787, William Herschel discovers the two largest moons of Uranus, six years after discovering the planet.

The two moons were named Oberon and Titania, after characters from Shakespeare's play "A Midsummer Night's Dream."

Oberon, the outermost of the two moons, is named after the king of the fairies in the play. It is the second largest of Uranus' moons and is known for its heavily cratered surface. Titania, named after the queen of the fairies in the play, is the largest of Uranus' moons. It is thought to have a mostly icy surface with a few large impact basins.

The discovery of Oberon and Titania showed that Uranus, like the other giant planets in the solar system, has a system of moons orbiting around it. Since the discovery of Oberon and Titania, many more Uranian moons have been discovered. Currently, there are a total of 29 known moons orbiting Uranus.