Discovered by W. Lassell
Date of Discovery 1851
Distance from Uranus 266,300 km
Radius 584.7 km
Mass 1.17 × 10^24 g
Orbital Eccentricity 0.0050
Orbital Inclination 0.36°
Orbital Period 4.1441772 days
Rotational Period Synchronous
Density (gm/cm3) ???
Similar to Ariel in size, density and shape, this darker moon has a uniform, cratered surface whereas Ariel's surface is more eclectic. Its surface is relatively dark, the darkest of Uranus's satellites, except for a bright ring at the 'north pole' that was first observed by Voyager 2. The nature and cause of this ring are unknown, but it may be floor of a crater. It is called the florescent cheerio.
Sources:
NASA.gov
space.com