Moons of Uranus these five, Titania, is 1,578 km in diameter and the eighth-largest moon in the Solar System, and about one-twentieth the mass the Earth's Moon. The orbits of the regular moons are nearly coplanar with Uranus's equator, which is tilted 97.77° to its orbit. Uranus's irregular moons have elliptical and strongly inclined (mostly retrograde) orbits at large distances from the planet. William Herschel discovered the first two moons, Titania and Oberon, in 1787, and the other three ellipsoidal moons were discovered in 1851 by William Lassell (Ariel and Umbriel) and in 1948 by Gerard Kuiper (Miranda). These five have planetary mass,
Oberon (operating system) the "Institut für Systemsoftware" of Johannes Kepler University of Linz, where one of the versions (V4) was maintained, the genealogy of the different versions of the Oberon System was the following: Oberon has a text user interface (TUI), which has to be differentiated from the terminal user interface. It combines the point-and-click convenience of a graphical user interface (GUI) with the linguistic strength of a command line interface (CLI) and is closely tied to the naming conventions of the Oberon language. Any text appearing (almost) anywhere on the screen can be edited and can therefore be used as command input.