Miranda, also designated Uranus V, is the smallest and innermost of Uranus's five round satellites. It was discovered by Gerard Kuiper on 16 February 1948 at McDonald Observatory in Texas, and named after Miranda from William Shakespeare's play The Tempest. Like the other large moons of Uranus, Miranda orbits close to its planet's equatorial plane. Because Uranus orbits the Sun on its side, Miranda's orbit is nearly perpendicular to the ecliptic and shares Uranus's extreme seasonal cycle.
Umbriel is the third-largest moon of Uranus. It was discovered on October 24, 1851, by William Lassell. It was discovered at the same time as Ariel and 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 endogenic processes, and the moon may have undergone an early endogenically driven resurfacing event that obliterated its older surface.
Puck the sixth-largest moon of Uranus. It was discovered in December 1985 by the Voyager 2 spacecraft. The name Puck follows the convention of naming Uranus's moons after characters from Shakespeare. The orbit of Puck lies between the rings of Uranus and the first of Uranus's large moons, Miranda. Puck is approximately spherical in shape and has diameter of about 162 km. It has a dark, heavily cratered surface, which shows spectral signs of water ice.
Oberon, also designated Uranus IV, is the outermost and second-largest major moon of the planet Uranus. It is the second-most massive of the Uranian moons, and the tenth-most massive moon in the Solar System. Discovered by William Herschel in 1787, Oberon is named after the mythical king of the fairies who appears as a character in Shakespeare's A Midsummer Night's Dream. Its orbit lies partially outside Uranus's magnetosphere.
Titania, also designated Uranus III, is the largest of the moons of Uranus. At a diameter of 1,578 kilometres (981 mi) it is the eighth largest moon in the Solar System, with a surface area comparable to that of Australia. Discovered by William Herschel in 1787, it is named after the queen of the fairies in Shakespeare's A Midsummer Night's Dream. Its orbit lies inside Uranus's magnetosphere.
Ariel is the fourth-largest moon of Uranus. Ariel orbits and rotates in the equatorial plane of Uranus, which is almost perpendicular to the orbit of Uranus and so has an extreme seasonal cycle.
A rift valley is a linear shaped lowland between several highlands or mountain ranges produced by the action of a geologic rift. Rifts are formed as a result of the pulling apart of the lithosphere due to extensional tectonics. The linear depression may subsequently be further deepened by the forces of erosion. More generally the valley is likely to be filled with sedimentary deposits derived from the rift flanks and the surrounding areas. In many cases rift lakes are formed. One of the best known examples of this process is the East African Rift. On Earth, rifts can occur at all elevations, from the sea floor to plateaus and mountain ranges in continental crust or in oceanic crust. They are often associated with a number of adjoining subsidiary or co-extensive valleys, which are typically considered part of the principal rift valley geologically.
Wunda is a large crater on the surface of Uranus' moon Umbriel. It is 131 km in diameter and is located near the equator of Umbriel. The crater is named after Wunda, a dark spirit of Australian aboriginal mythology.
Perdita is an inner satellite of Uranus. Perdita's discovery was very complicated, as the first photographs of Perdita were taken by the Voyager 2 spacecraft in 1986, but it was not recognized from the photographs for more than a decade. In 1999, the moon was noticed by Erich Karkoschka and reported. But because no further pictures could be taken to confirm its existence, it was officially demoted in 2001. However, in 2003, pictures taken by the Hubble Space Telescope managed to pick up an object where Perdita was supposed to be, finally confirming its existence.
Uranus, the seventh planet of the Solar System, has 28 confirmed moons. Most of them are named after characters that appear in, or are mentioned in, the works of William Shakespeare and Alexander Pope. Uranus's moons are divided into three groups: thirteen inner moons, five major moons, and ten irregular moons. The inner and major moons all have prograde orbits and are cumulatively classified as regular moons. In contrast, the orbits of the irregular moons are distant, highly inclined, and mostly retrograde.
Odysseus is the largest crater on Saturn's moon Tethys. It is 445 km across, more than 2/5 of the moon's diameter, and is one of the largest craters in the Solar System. It is situated in the western part of the leading hemisphere of the moon—the latitude and longitude of its center are 32.8°N and 128.9°W, respectively. It is named after the Greek hero Odysseus from Homer's the Iliad and the Odyssey.
The rings of Uranus are intermediate in complexity between the more extensive set around Saturn and the simpler systems around Jupiter and Neptune. The rings of Uranus were discovered on March 10, 1977, by James L. Elliot, Edward W. Dunham, and Jessica Mink. William Herschel had also reported observing rings in 1789; modern astronomers are divided on whether he could have seen them, as they are very dark and faint.
Ithaca Chasma is a valley (graben) of Saturn's moon Tethys, named after the island of Ithaca, in Greece. It is up to 100 km (62 mi) wide, 3–5 km (1.9–3.1 mi) deep and 2,000 km (1,200 mi) long, running approximately three-quarters of the way around Tethys' circumference, making it one of the longer valleys in the Solar System. Ithaca Chasma is approximately concentric with Odysseus crater.
The exploration of Uranus has, to date, been through telescopes and a lone probe by NASA's Voyager 2 spacecraft, which made its closest approach to Uranus on January 24, 1986. Voyager 2 discovered 10 moons, studied the planet's cold atmosphere, and examined its ring system, discovering two new rings. It also imaged Uranus' five large moons, revealing that their surfaces are covered with impact craters and canyons.
Hamlet is the largest crater on the known part of the surface of Uranus' moon Oberon. It has diameter of about 206 km and is named after the title character of the play Hamlet, by William Shakespeare. The crater has a dark floor and is surrounded by a system of bright rays, which are ice ejecta deposited during the impact event. The nature of the dark material on the floor is unknown, but it may have erupted from the depth through cryovolcanism. The crater was first imaged by the Voyager 2 spacecraft in January 1986.
The Messina Chasmata are the largest canyon or system of canyons on the surface of the Uranian moon Titania, named after a location in William Shakespeare's comedy Much Ado About Nothing. The 1,492 km (927 mi)- long feature includes two normal faults running NW–SE, which bound a down-dropped crustal block forming a structure called a graben. The graben cuts impact craters, which probably means that it was formed at a relatively late stage of the moon's evolution, when the interior of Titania expanded and its ice crust cracked as a result. The Messina Chasmata have only a few superimposed craters, which also implies being relatively young. The feature was first imaged by Voyager 2 in January 1986.
Ursula is a large crater on Uranus's moon Titania. It is about 135 km across, and is cut by Belmont Chasma. It is named after Hero's attendant in William Shakespeare's comedy Much Ado About Nothing.
Rousillon Rupes is a scarp on the surface of the Uranian moon Titania named after "Bertram, count of Rousillon" in William Shakespeare's comedy All's Well That Ends Well. The 402 km long feature is a normal fault situated near the equator and running perpendicular to it. The scarp cuts impact craters, which probably means that it was formed at a relatively late stage of moon's evolution, when the interior of Titania expanded and its ice crust cracked as a result. Rousillon Rupes has only few crater superimposed on it, which also implies its relatively young age. The scarp was first imaged by Voyager 2 spacecraft in January 1986.
The Kachina Chasmata are the longest canyon or system of canyons on the surface of the Uranian moon Ariel. The name comes from a spirit in Hopi mythology. The 622 km long and 50 km wide chasmata arise from a system of normal faults running from the north-west to south-east. The faults bound down-dropped crustal blocks forming structures called graben. The canyons cut the cratered terrain, which means that they were formed at a relatively late stage of the moon's evolution, when the interior of Ariel expanded and its ice crust cracked as a result. The floor of the canyons is not visible on the images obtained by the Voyager 2 spacecraft in January 1986; thus, whether it is covered by smooth plains like the floors of other Arielian graben is currently unknown.
Yangoor is the largest known crater on the surface of the Uranian moon Ariel. The name comes from a spirit that brings day in Australian Aboriginal mythology. It is about 80 km in diameter and is located approximately 450 km from Ariel's south pole. The northwestern edge of the crater was erased by formation of ridged terrain. The crater lacks bright ejecta deposits and was imaged for the first time by the Voyager 2 spacecraft in January 1986.
