BotBuhdy logoBotBuhdyMoon Guide

Moons of Uranus

Uranus's moons: Shakespeare on ice

Uranus has 29 known moons. Unlike other moons named after myths, they are named after characters from the plays of William Shakespeare and a poem by Alexander Pope.

Uranus's moon Miranda, a patchwork of grooved and cratered terrain with giant cliffs

NASA/JPL-Caltech, Voyager 2 (PIA18185), 24 Jan 1986. Public domain.

Meet the moons

Miranda

Diameter
472 km
Discovered
1948, Gerard Kuiper
Known for
giant cliffs

Miranda looks like a patchwork, as if it had been smashed apart and reassembled. Huge oval "coronae" with grooved racetrack patterns sit next to old cratered ground.

Its cliff Verona Rupes is estimated to be up to 20 km high, perhaps the tallest cliff in the solar system. In the low gravity, a fall from the top would last several minutes.

Uranus's moon Miranda, a patchwork of grooved and cratered terrain with giant cliffs
Miranda from Voyager 2, January 1986.NASA/JPL-Caltech, Voyager 2 (PIA18185), 24 Jan 1986. Public domain.

The big four

  • Titania (1,578 km): the largest, with canyons hundreds of kilometres long.
  • Oberon (1,523 km): old and heavily cratered.
  • Umbriel (1,169 km): the darkest of the big moons.
  • Ariel (1,158 km): the brightest, with the youngest surface and long valleys.

Uranus is tipped on its side, so its moons, which orbit above its equator, go through extreme 42-year-long seasons of light and dark.

Uranus's five largest moons in a row, from small Miranda to Oberon
Uranus's five largest moons, from Miranda (left) to Oberon, from Voyager 2.NASA/JPL, Voyager 2 (PIA01975), Jan 1986. Public domain.

Only one visit, so far

Everything we know up close comes from Voyager 2, which flew past on 24 January 1986 and could only photograph the southern halves of the moons. Ground telescopes and the James Webb Space Telescope keep finding new small moons. US scientists ranked a Uranus Orbiter and Probe as the top priority for a new flagship mission in their 2022 decadal survey.

Could life be here?

Our rough guide, from 0 (no chance) to 5 (among the best places to look). No life has been found beyond Earth.

Could life be here? Titania, Oberon, Ariel and Umbriel

  • Models suggest thin salty oceans may survive deep inside
  • Ariel shows signs of past resurfacing
  • Very cold and little internal heat
  • Almost no data

Verdict: Unlikely, but we have barely looked.

Could life be here? Miranda

  • A 2024 study suggests it may have had an ocean in the recent past
  • Small and cold today

Verdict: Very unlikely.

Quick answers

How many moons does Uranus have?

29 known moons as of 2026.

Why are Uranus's moons named after Shakespeare characters?

The tradition began with John Herschel, son of Uranus's discoverer, who named the first ones after characters from Shakespeare and Alexander Pope. It has continued ever since.

Has any spacecraft visited Uranus?

Only Voyager 2, which flew past in January 1986.

Sources and credits

  1. NASA Science, Uranus moons.
  2. National Academies (2022), Origins, Worlds, and Life: Planetary Science and Astrobiology Decadal Survey.
  3. NASA/JPL Voyager 2 images.

Photos credited to NASA, NOAA and other public-domain sources are used with thanks; BotBuhdy adds a small botbuhdy.com mark. Pictures labelled AI-generated illustration are artist-style illustrations made for this page, not photographs.