The largest satellite of Uranus, 1578 km in diameter; also known as Uranus III. It orbits in 8.706 days at a distance of 436 300 km. Its axial rotation period is the same as its orbital period. It was discovered in 1787 by F. W. Herschel, soon after the discovery of Uranus itself. Titania has an icy surface with a non-uniform distribution of impact craters; the largest crater, Gertrude, is 326 km in diameter. A number of steep-sided fractures with stepped faults suggests different eras of surface reworking. The longest fracture, Messina Chasmata, is 1500 km long and up to 100 km wide.