Setebos, a moon of Uranus
10,823,023 miles
30 miles
Setebos is one of Uranus’s outer irregular moons and follows a retrograde orbit, meaning it travels in the opposite direction to Uranus’s rotation. With a diameter of around 48 kilometres (30 miles), it is a small, faint satellite located far beyond the planet’s larger regular moons.
It was discovered in 1999 by John J. Kavelaars, Brett J. Gladman, Matthew J. Holman, and others, using the Canada-France-Hawaii Telescope at Mauna Kea Observatory, Hawaii. Like other irregular moons, Setebos likely began life as an independent object in the outer Solar System before being captured by Uranus’s gravity.
Its distant, tilted, and elongated orbit suggests it may be related to other retrograde moons such as Prospero and Stephano, possibly originating from a single larger body that broke apart after capture.
Setebos is named after a god worshipped by the witch Sycorax in William Shakespeare’s The Tempest. Although never appearing as a character, Setebos is mentioned in the play by Caliban, Sycorax’s son, as a source of his mother’s magical power.
This naming continues Uranus’s tradition of drawing from Shakespeare's works for its moon names, and especially The Tempest for many of its irregular moons.
