Moon
Umbriel
Moon of Uranus
Moon of Uranus
Photo: NASA / Jet Propulsion Lab · Public domain · Wikimedia Commons
Umbriel is the third-largest moon of Uranus. It was discovered on October 24, 1851, by William Lassell at the same time as neighboring moon Ariel. It was named after a character in Alexander Pope's 1712 poem The Rape of the Lock. Umbriel consists mainly of ice with a substantial fraction of rock, and may be differentiated into a rocky core and an icy mantle. The surface is the darkest among Uranian moons and appears to have been shaped primarily by impacts; however, the presence of canyons suggests early internal processes. The moon may have undergone an early endogenically driven resurfacing event that obliterated its older surface.
Description from Wikipedia (CC BY-SA 4.0).
Key facts
Distance
Orbits Uranus
Orbits
Uranus
Mean radius
585 km
Orbital period
4.14 days
Discovered
1851 · William Lassell
Orbits
Uranus
