Setebos🌙

Setebos is one of Uranus’s distant irregular moons, discovered in 1999, and is thought to be about 48–50 kilometers in diameter, making it a relatively small and faint object compared to the major moons. It orbits Uranus at an extremely far distance—over 17 million kilometers away—and follows a retrograde path, meaning it moves in the opposite direction of the planet’s rotation. Its orbit is also highly inclined and quite eccentric, which suggests Setebos was likely not formed around Uranus but was instead captured by the planet’s gravity long ago, possibly from a population of icy bodies in the outer Solar System. The moon’s surface is believed to be very dark with a low albedo, meaning it reflects little sunlight and is likely composed of carbon-rich, primitive material. Setebos may be part of a loose group of irregular moons with similar orbits, although differences in surface color between Setebos and nearby moons suggest they may not all share the same origin. Like many of Uranus’s moons, its name comes from Shakespeare—in this case Setebos, a deity mentioned in The Tempest—adding a cultural and mythological connection to an otherwise remote and mysterious world.