Moon of Uranus · Updated May 2026
Oberon.
Oberon is the second-largest moon of Uranus at 1,523 km diameter and the outermost of its major moons. Its ancient surface is heavily cratered, with mysterious dark patches on some crater floors and a 6 km-tall mountain near the limb in the only Voyager 2 close-up.
View Uranus system in 3D →Key facts
Oberon's leading hemisphere is slightly redder than the trailing one — possibly the result of charged particles from Uranus's magnetosphere processing surface material differently on each side.
About Oberon
Named after the king of the fairies in A Midsummer Night's Dream. The dark crater floors may be primordial carbon-rich material exposed by impacts.
How to view Oberon in 3D
Oberon orbits Uranus in real time inside the interactive viewer. Open the parent body to see the orbital geometry, or use the object browser to fly directly to the moon and observe its rotation, surface, and orbit.
Open the Uranus system →Sources & methodology
Numbers cross-referenced with the sources below; updated May 2026.