Moons of Uranus and "The Rape of the Lock" (although at present only Ariel, Umbriel, and Belinda have names drawn from the latter; all the rest are from Shakespeare). At first, the outermost moons were all named after characters from one play, "The Tempest"; but with Margaret being named from "Much Ado About Nothing" that trend has ended. Some asteroids share names with moons of Uranus: 171 Ophelia, 218 Bianca, 593 Titania, 666 Desdemona, 763 Cupido, and 2758 Cordelia. The Uranian satellite system is the least massive among those of the giant planets. Indeed, the combined mass of the five major satellites is
Moons of Uranus which is made primarily of ice. The ice component may include ammonia and carbon dioxide. Their surfaces are heavily cratered, though all of them (except Umbriel) show signs of endogenic resurfacing in the form of lineaments (canyons) and, in the case of Miranda, ovoid race-track like structures called coronae. Extensional processes associated with upwelling diapirs are likely responsible for the origin of the coronae. Ariel appears to have the youngest surface with the fewest impact craters, while Umbriel's appears oldest. A past 3:1 orbital resonance between Miranda and Umbriel and a past 4:1 resonance between Ariel and Titania are thought