Uranus' Moon Titania - Universe Today Universe Today by Matt Williams Like all of the Solar Systems’ gas giants, Uranus has an extensive system of moons. In fact, astronomers can now account for 27 moons in orbit around Uranus. Of these, none are greater in size, mass, or surface area than Titania. One of the first moon’s to be discovered around Uranus, this heavily cratered and scarred moon was appropriately named after the fictional Queen of the Fairies. Discovery and Naming: Titania was discovered by William Herschel on January 11th, 1787, the English astronomer who had discovered Uranus in 1781. The discovery was also made on the same day that he discovered Oberon , Uranus’ second-largest moon. Although Herschel reported observing four other moons at the time, the Royal Astronomical Society would later determine that this claim was spurious. It would be almost five decades after Titania and Oberon was discovered that an astronomer other than Herschel would observe them.

In addition, Titania would be referred to as “the first satellite of Uranus” for many years – or by the designation Uranus I, which was given to it by William Lassell in 1848. By 1851, Lassell began to number all four known satellites in order of their distance from the planet by Roman numerals, at which point Titania’s designation became Uranus III. By 1852, Herschel’s son John, and at the behest of Lassell himself, suggested the moon’s name be changed to Titania, the Queen of the Fairies in A Midsummer Night’s Dream. This was consistent with all of Uranus’ satellites, which were given names from the works of William Shakespeare and Alexander Pope. A montage of Uranus’s moons. Image credit: NASA Size, Mass and Orbit: With a diameter of 1,578 kilometers, a surface area of 7,820,000 km² and a mass of 3.527±0.09 × 1021 kg, Titania is the largest of Uranus’ moons and the eighth largest moon in the Solar System.

At a distance of about 436,000 km (271,000 mi), Titania is also the second farthest from the planet of the five major moons. Titania’s moon also has a small eccentricity and is inclined very little relative to the equator of Uranus. It’s orbital period, which is 8.7 days, is also coincident with it’s rotational period. This means that Titania is a synchronous (or tidally-locked) satellite, with one face always pointing towards Uranus at all times. Because Uranus orbits the Sun on its side, and its moons orbit the planet’s equatorial plane, they are all subject to an extreme seasonal cycle, where the northern and southern poles experience 42 years of either complete darkness or complete sunlight. Composition: Scientists believe Titania is composed of equal parts rock (which may include carbonaceous materials and organic compounds) and ice. This is supported by examinations that indicate that Titania has an unusually high-density for a Uranian satellite (1.71 g/cm³).

The presence of water ice is supported by infrared spectroscopic observations made in 2001–2005, which have revealed crystalline water ice on the surface of the moon. Uranus and its five major moons, with Titania being the farthest left. Credit: space.com It is also believed that Titania is differentiated into a rocky core surrounded by an icy mantle. If true, this would mean that the core’s radius is approx. 520 km (320 mi), which would mean the core accounts for 66% of the radius of the moon, and 58% of its mass. As with Uranus’ other major moons, the current state of the icy mantle is unknown. However, if the ice contains enough ammonia or other antifreeze, Titania may have a liquid ocean layer at the core-mantle boundary. The thickness of this ocean, if it exists, is up to 50 km (31 mi) and its temperature is around 190 K. Naturally, it is unlikely that such an ocean could support life. But assuming this ocean supports hydrothermal vents on its floor, it is possible life could exist in small patches close to the core.

However, the internal structure of Oberon depends heavily on its thermal history, which is poorly known at present. Voyager 2: The only direct observations made of Titania were conducted by the Voyager 2 space probe, which photographed the moon during its flyby of Uranus in January 1986. These images covered about 40% of the surface, but only 24% was photographed with the precision required for geological mapping. Voyager’s flyby of Titania coincided with the southern hemisphere’s summer solstice, when nearly the entire northern hemisphere was unilluminated. As with the other major moon’s of Uranus, this prevented the surface from being mapped in any detail. No other spacecraft has visited the Uranian system or Titania before or since, and no mission is planned in the foreseeable future. Interesting Facts: Titania is intermediate in terms of brightness, occupying a middle spot between the dark moons of Oberon and Umbriel and the bright moons of Ariel and Miranda . It’s surface is generally red in color (less so than Oberon), except where fresh impact have taken place, which have left the surface blue in color.

The surface of Titania is less heavily cratered than the surface of either Oberon or Umbriel, suggesting that its surface is much younger. Like all of Uranus’ major moons, it’s geology is influenced by a combination of impact craters and endogenic resurfacing. Whereas the former acted over the moon’s entire history and influenced all its surfaces, the latter processes were mainly active following the moon’s formation and resulted in a smoothing out of its features – hence the low number of present-day impact craters. Overall, scientists have recognized three classes of geological feature on Titania. These include craters, faults (or scarps) and what are known as grabens (sometimes called canyons). Titania’s craters range in diameter from a few kilometers to 326 kilometers – in the case of the largest known crater, Gertrude . Titania’s surface is also intersected by a system of enormous faults (scarps); and in some places, two parallel scarps mark depressions in the satellite’s crust, forming grabens (aka. canyons).

The grabens on Titania range in diameter from 20 to 50 kilometers (12–31 mi) and in a relief (i.e. depth) from 2 to 5 km. The most prominent graben on Titania is the Messina Chasma, which runs for about 1,500 kilometers (930 mi) from the equator almost to the south pole. The grabens are probably the youngest geological features on Titania, since they cut through all craters and even the smooth plains. Voyager 2’s highest-resolution image of Titania, showing cratered plains, enormous rifts and long scarps. Near the bottom, the crater Ursula is split by the graben Belmont Chasma. Credit: NASA Like Oberon, the surface features on Titania have been named after characters in works by Shakespeare, with all of the physical features are named after female characters. For instance, the crater Gertrude is named after Hamlet’s mother, while other craters – Ursula, Jessica, and Imogen – are named after characters from Much Ado About Nothing, The Merchant of Venice, and Cymebline, respectively.

Interestingly, the presence of carbon dioxide on the surface suggests that Titania may also have a tenuous seasonal atmosphere of CO², much like that of the Jovian moon Callisto . Other gases, like nitrogen or methane, are unlikely to be present, because Titania’s weak gravity could not prevent them from escaping into space. Like all of Uranus’ moons, much remains to be discovered about this most-massive of her satellites. In the coming years, one can only hope that NASA, the ESA, or other space agencies decide that another Voyager-like mission is need to the outer Solar System. Until such time, Uranus and the many moons that orbit it will continue to keep secrets from us. You should also check out Titania and the moon Titania . Astronomy Cast has an episode on William Herschel you will find interesting. Reference: Uranus Uranus The important thing is not to stop questioning. - Albert Einstein Satellites of Uranus Uranus is the seventh planet from the Sun and is the third largest in the solar system. It was discovered by William Herschel in 1781.

It has an equatorial diameter of 51,800 kilometers (32,190 miles) and orbits the Sun once every 84.01 Earth years. It has a mean distance from the Sun of 2.87 billion kilometers (1.78 billion miles). It rotates about its axis once every 17 hours 14 minutes. Uranus has at least 22 moons. The two largest moons, Titania and Oberon , were discovered by William Herschel in 1787. The atmosphere of Uranus is composed of 83% hydrogen, 15% helium, 2% methane and small amounts of acetylene and other hydrocarbons. Methane in the upper atmosphere absorbs red light, giving Uranus its blue-green color. The atmosphere is arranged into clouds running at constant latitudes, similar to the orientation of the more vivid latitudinal bands seen on Jupiter and Saturn. Winds at mid-latitudes on Uranus blow in the direction of the planet's rotation. These winds blow at velocities of 40 to 160 meters per second (90 to 360 miles per hour).

Radio science experiments found winds of about 100 meters per second blowing in the opposite direction at the equator. Uranus is distinguished by the fact that it is tipped on its side. Its unusual position is thought to be the result of a collision with a planet-sized body early in the solar system's history. Voyager 2 found that one of the most striking influences of this sideways position is its effect on the tail of the magnetic field, which is itself tilted 60 degrees from the planet's axis of rotation. The magnetotail was shown to be twisted by the planet's rotation into a long corkscrew shape behind the planet. The magnetic field source is unknown; the electrically conductive, super-pressurized ocean of water and ammonia once thought to lie between the core and the atmosphere now appears to be nonexistent. The magnetic fields of Earth and other planets are believed to arise from electrical currents produced in their molten cores. Uranus' Rings In 1977, the first nine rings of Uranus were discovered. During the Voyager encounters, these rings were photographed and measured, as were two other new rings and ringlets. Uranus' rings are distinctly different from those at Jupiter and Saturn .

The outermost epsilon ring is composed mostly of ice boulders several feet across. A very tenuous distribution of fine dust also seems to be spread throughout the ring system. There may be a large number of narrow rings, or possibly incomplete rings or ring arcs, as small as 50 meters (160 feet) in width. The individual ring particles were found to be of low reflectivity. At least one ring, the epsilon, was found to be gray in color. The moons Cordelia and Ophelia act as shepherd satellites for the epsilon ring. Uranus Statistics Mean distance from the Sun (km) 2,870,990,000 Mean distance from the Sun (Earth = 1) 19.1914 Equatorial surface gravity (m/sec^2) 7.77 Views of Uranus Uranus The greenish color of it atmosphere is due to methane and This view of Uranus was acquired by Voyager 2 on January 10, 1986. The blue-green appearance of its atmosphere results from methane and high-altitude photochemical smog. This gas absorbs red wavelengths from the incoming sunlight, leaving the predominant bluish color seen here.

Towards the bottom of the image a few clouds can be seen. This image is one of the few Voyager pictures that shows this type of cloud. (Copyright Calvin J. Hamilton) The Interior of Uranus Our knowledge of the internal structure of Uranus is inferred from the planet's radius, mass, period of rotation, the shape of its gravitational field and the behavior of hydrogen, helium, and water at high pressure. Its internal structure is similar to that of Neptune except for the fact that it is less active in terms of atmospheric dynamics and interior heat flow. This cut-away view shows Uranus composed of an outer envelope of molecular hydrogen, helium and methane roughly the mass of one to two Earths. Below this region Uranus appears to be composed of a mantle rich in water, methane, ammonia, and other elements. These elements are under high temperatures and pressures deep within the planet. The mantle is equivalent to 10 to 15 earth masses. Uranus's core is composed of rock and ice, and is likely no more than one Earth mass. (Copyright Calvin J. Hamilton) Uranus with its Rings This is the highest resolution image of Uranus with its rings ever assembled.

Four separate images were mosaicked together to create the picture of Uranus. The rings were made from two high resolution images of Uranus's rings in which a strip was cut out and projected for a full 360 degrees. The rings and planet are to scale and shows the view Voyage 2 had of at the time the images were taken. The rings shown in the picture are Epsilon, Delta, Gamma, Eta, Beta, Alpha, 4, 5, and 6. Although there are other rings, these are the ones that could be seen on the Voyger 2 images at the point in time in which the pictures were taken. (Copyright Calvin J. Hamilton) Uranus in True and False Color These two pictures of Uranus, one in true color (left) and the other in false color, were compiled from images returned January 17, 1986, by the narrow-angle camera of Voyager 2. The spacecraft was 9.1 million kilometers (5.7 million miles) from the planet, several days from closest approach. The picture at left has been processed to show Uranus as human eyes would see it from the vantage point of the spacecraft.

The picture is a composite of images taken through blue, green and orange filters. The darker shadings at the upper right of the disk correspond to the day-night boundary on the planet. Beyond this boundary lies the hidden northern hemisphere of Uranus, which remains in total darkness as the planet rotates. The blue-green color results from the absorption of red light by methane gas in Uranus' deep, cold and remarkably clear atmosphere. The picture at right uses false color and extreme contrast enhancement to bring out subtle details in the polar region of Uranus. Images obtained through ultraviolet, violet and orange filters were respectively converted to the same blue, green and red colors used to produce the picture at left. The very slight contrasts visible in true color are greatly exaggerated here. In this false-color picture, Uranus reveals a dark polar hood surrounded by a series of progressively lighter concentric bands. One possible explanation is that a brownish haze or smog, concentrated over the pole, is arranged into bands by zonal motions of the upper atmosphere. The bright orange and yellow strip at the lower edge of the planet's limb is an artifact of the image enhancement. In fact, the limb is dark and uniform in color around the planet.

(Courtesy NASA/JPL) Voyager Farewell Image This view of Uranus was recorded by Voyager 2 on January 25, l986, as the spacecraft left the planet behind and set forth on its cruise to Neptune . Voyager was 1 million kilometers (620,000 miles) from Uranus when it acquired this wide-angle view. The picture has a resolution of 140 kilometers (90 miles). The thin crescent of Uranus is seen at an angle of 153 degrees between the spacecraft, the planet and the Sun . Even at this extreme angle, Uranus retains the pale blue-green color seen by ground-based astronomers and recorded by Voyager during its historic encounter. This color results from the presence of methane in Uranus' atmosphere; the gas absorbs red wavelengths of light, leaving the predominant hue seen here. The tendency for the crescent to become white at the extreme edge is caused by the presence of a high-altitude haze. (Copyright Calvin J.

Hamilton) Hubble Tracks Rotation of Uranus This view of Uranus was acquired by NASA's Hubble Space Telescope and reveals a pair of bright clouds in the planet's southern hemisphere, and a high altitude haze that forms a "cap" above the planet's south pole. This is just one view of a sequence of three that can be obtained by selecting the above gif image. Hubble's new view was obtained on August 14, 1994, when Uranus was 2.8 billion kilometers (1.7 billion miles) from Earth. These atmospheric details were only previously seen by the Voyager 2 spacecraft, which flew by Uranus in 1986. Since then, detailed observations of Uranus's atmospheric features have not been possible because the planet is at the resolution limit of ground-based telescopes. Hubble's Wide Field Planetary Camera 2 observed Uranus through a filter that is sensitive to light reflected by a pair of high altitude clouds.

This makes a high altitude haze over Uranus' south polar region clearly visible, along with a pair of high altitude clouds or plume-type features that are 4,300 and 3,100 kilometers (2,500 and 1,800 miles) across, respectively. (Credit Kenneth Seidelmann, U.S. Naval Observatory, and NASA) Two additional Hubble Telescope images can be found here. Uranus Uranus Ring System This dramatic Voyager 2 picture reveals a continuous distribution of small particles throughout the Uranian ring system. The unique geometry of this picture makes the previously unseen lanes of fine dust particles visible. All the formerly known rings are visible here; however, some of the brightest features in the image are bright dust lanes not previously seen. The combination of this unique geometry and a long, 96 second exposure allowed this spectacular observation. The image was acquired through the clear filter of Voyager's wide-angle camera. The long exposure produced a noticeable, non-uniform smear as well as streaks due to trailed stars. (Copyright Calvin J. Hamilton) Shepherd Satellites The discovery of two shepherd satellites has advanced our understanding of the structure of the Uranian rings.

The moons, Cordelia (1986U7) and Ophelia (1986U8), are seen here on either side of the bright epsilon ring; all 9 of the known Uranian rings are also visible. The epsilon ring appears surrounded by a dark halo as a result of image processing; occasional blips seen on the ring are also artifacts. Lying inward from the epsilon ring are the delta, gamma and eta rings; the beta and alpha rings; and finally the barely visible 4, 5 and 6 rings. The rings have been studied since their discovery in 1977. (Courtesy NASA/JPL) Pseudo-image of Uranus' Ring This pseudo-image of Uranus' rings was generated by using Voyager 2 frame FDS 26852.19. This image was taken in forward scattered light and shows dust bands not seen in any other image. A 3 pixel wide slice was taken from the most detailed part of the image, averaged to a 1 pixel wide image, then rotated 360 degrees and projected into perspective view. The real color of the rings are neutral gray and they are as dark as charcoal. (Courtesy A.

Tayfun Oner) Uranus' Rings The 9 known rings of Uranus are visible here. The somewhat fainter, pastel lines seen between the rings are artifacts of computer enhancement. Six narrow-angle images were used to extract color information from the extremely dark and faint rings. The final image was made from three color averages and represents an enhanced, false-color view. The image shows that the brightest, or epsilon, ring at top is neutral in color, with the fainter 8 remaining rings showing color differences between them. (Courtesy NASA/JPL) Uranian System This montage of the Uranian system was prepared from an assemblage of images taken by the Voyager 2 spacecraft during its Uranus encounter in January 1986. This artist's view shows Ariel in the forefront, with Uranus rising behind. Traversing clockwise from Ariel are the satellites Umbriel , Oberon , Titania , Miranda , and the small moon Puck . (Copyright Calvin J. Hamilton) The following is a summary of the rings of Uranus. Name Science - Observatory - Uranus View the current phase of the moon Uranus is the seventh planet from the Sun and is the third largest in the solar system.

William Herschel discovered it in 1781. It has an equatorial diameter of 51,800 kilometers (32,190 miles) and orbits the Sun once every 84.01 Earth years. It has a mean distance from the Sun of 2.87 billion kilometers (1.78 billion miles). It rotates about its axis once every 17 hours 14 minutes. Uranus has at least 22 moons. William Herschel discovered the two largest moons, Titania and Oberon, in 1787. The atmosphere of Uranus is composed of 83% hydrogen, 15% helium, 2% methane and small amounts of acetylene and other hydrocarbons. Methane in the upper atmosphere absorbs red light, giving Uranus its blue-green color. The atmosphere is arranged into clouds running at constant latitudes, similar to the orientation of the more vivid latitudinal bands seen on Jupiter and Saturn. Winds at mid-latitudes on Uranus blow in the direction of the planet's rotation.

These winds blow at velocities of 40 to 160 meters per second (90 to 360 miles per hour). Radio science experiments found winds of about 100 meters per second blowing in the opposite direction at the equator. Uranus is distinguished by the fact that it is tipped on its side. Its unusual position is thought to be the result of a collision with a planet-sized body early in the solar system's history. Voyager 2 found that one of the most striking influences of this sideways position is its effect on the tail of the magnetic field, which is itself, tilted 60 degrees from the planet's axis of rotation. The magnetotail was shown to be twisted by the planet's rotation into a long corkscrew shape behind the planet. The magnetic field source is unknown; the electrically conductive, super-pressurized ocean of water and ammonia once thought to lie between the core and the atmosphere now appears to be nonexistent. The magnetic fields of Earth and other planets are believed to arise from electrical currents produced in their molten cores.

Because of its size and distance, it takes Uranus 84 years for it to orbit around the sun, but only 17 hours and 15 minutes for it to rotate on its axis. In 1977, U.S astronomer James L. Elliot discovered five rings around Uranus' equator while he was studying a star behind the planet. He named the rings Alpha, Beta, Gamma, Delta, and Epilson(starting from inside to out). Four more were discovered when Voyager 2 flew by in January 1986. Uranus has 15 moons. Its two largest are Obieron and Titania discovered by Herschel in 1787. Two others, Umbriel and Ariel were discovered in 1851 by British astronomer William Lassil, and Miranda was discovered by U.S Astronomer Gerard Peter Kuiper in 1948.

Uranus - Observations from Earth | planet | Britannica.com Observations from Earth Titania Uranus was discovered by the English astronomer William Herschel , who had undertaken a survey of all stars down to eighth magnitude —i.e., those about five times fainter than stars visible to the naked eye. On March 13, 1781, he found “a curious either nebulous star or perhaps a comet,” distinguished from the stars by its clearly visible disk. Its lack of any trace of a tail and its slow motion led within months to the conclusion that the object was a planet, rather than a comet , moving in a nearly circular orbit well beyond Saturn. Observations of the new planet during the next 65 years revealed discrepancies in its orbital motion—evidence of gravitational forces on Uranus that were not due to any other known planet, which ultimately led to the discovery of yet more distant Neptune in 1846. Herschel suggested naming his new discovery Georgium Sidus (Latin: “Georgian Planet”) after his patron, King George III of England, while the French favoured the name Herschel.

The planet was eventually named according to the tradition of naming planets for the gods of Greek and Roman mythology; Uranus is the father of Saturn, who is in turn the father of Jupiter. The orbit of Uranus seemed to fit the prediction of a simple empirical rule, Bode’s law , that had been devised in 1766 and popularized in 1772 to explain the orbital distances from the Sun of Earth and the five planets known to the ancients. In addition, where the law predicted another planet between Mars and Jupiter, the asteroids seemed to fill the gap, beginning with the discovery of the largest asteroid , Ceres , in 1801. For about three-quarters of a century, these successes overcame doubts stemming from the facts that the law had no theoretical basis and that it provided only an approximate fit to the planetary orbits. Neptune turned out to not fit the pattern at all (being 21 percent closer to the Sun than the law predicted), nor did Pluto, and now Bode’s law is of only historical significance.

Similar Topics Mars After his discovery of Uranus, Herschel continued to observe it with larger and better telescopes and eventually discovered its two largest moons, Titania and Oberon , in 1787. (Herschel claimed to have discovered four more moons in the 1790s, but his reputation was so esteemed that the nonexistence of those moons was not realized until the mid-19th century despite the almost total lack of corroboration by other astronomers.) Two more major moons, Ariel and Umbriel , were discovered by the English astronomer William Lassell in 1851. The names of the four moons come from English literature, taken from characters of William Shakespeare and Alexander Pope , and were proposed by Herschel’s son, John . (The names of Uranus’s children, the Titans, already had been appropriated for Saturn’s moons.) A fifth major moon, Miranda , was detected photographically by the Dutch American astronomer Gerard P. Kuiper in 1948. The tradition of naming Uranian moons after characters in Shakespeare’s and Pope’s works continued to be applied to subsequent discoveries.

Spacecraft exploration Although the missions of the twin Voyager 1 and 2 spacecraft originally called for flybys of only Jupiter and Saturn, the timing of Voyager 2’s launch allowed for a change to its trajectory so that it could be retargeted to Uranus and Neptune for an extended mission, which ultimately was carried out. After more than eight years in space, Voyager 2 sped through the Uranian system on January 24, 1986. Its instruments provided an accurate determination of the masses and radii of the planet and its major moons, detected Uranus’s magnetic field and determined its strength and orientation, and measured the planet’s interior rotation rate. Images of the Uranian system, which totaled more than 8,000, revealed for the first time the weather patterns in the planet’s atmosphere and the surface characteristics of the moons. In addition to Voyager’s discoveries of new moons, a ring, and dust bands between the rings, it provided details of ring structure at scales not achievable from Earth. Yet, despite these achievements, Voyager left many unanswered questions that only another spacecraft mission or a major advance in Earth-based observational technology would be able to address. No future missions to Uranus are planned.

This computer animation shows the Voyager 2 space probe’s encounter with the planet Uranus on Jan. … NASA BBC - Solar System - William Herschel (pictures, video, facts & news) Asteroids explained Patrick Moore describes the asteroid belt and its discovery. Sir Patrick Moore explains how the asteroid belt between Mars and Jupiter was discovered. He also talks about Bode's Law, an 18th century empirical rule that was once thought to predict planets' orbits. It is now discredited by astronomers, including Sir Patrick. About William Herschel Frederick William Herschel,KH, FRS (German: Friedrich Wilhelm Herschel; 15 November 1738 – 25 August 1822) was a British astronomer and composer of German origin, and brother of fellow astronomer Caroline Herschel, with whom he worked. Born in the Electorate of Hanover, Herschel followed his father into the Military Band of Hanover, before migrating to Great Britain in 1757 at the age of nineteen. Herschel constructed his first large telescope in 1774, after which he spent nine years carrying out sky surveys to investigate double stars.

The resolving power of the Herschel telescopes revealed that the nebulae in the Messier catalogue were clusters of stars. Herschel published catalogues of nebulae in 1802 (2,500 objects) and in 1820 (5,000 objects). In the course of an observation on 13 March 1781 he realized that one celestial body he had observed was not a star, but a planet, Uranus. This was the first planet to be discovered since antiquity and Herschel became famous overnight. As a result of this discovery, George III appointed him Court Astronomer. He was elected as a Fellow of the Royal Society and grants were provided for the construction of new telescopes. Herschel pioneered the use of astronomical spectrophotometry as a diagnostic tool, using prisms and temperature measuring equipment to measure the wavelength distribution of stellar spectra. Other work included an improved determination of the rotation period of Mars, the discovery that the Martian polar caps vary seasonally, the discovery of Titania and Oberon (moons of Uranus) and Enceladus and Mimas (moons of Saturn).

In addition, Herschel discovered infrared radiation. Herschel was made a Knight of the Royal Guelphic Order in 1816. He was the first President of the Royal Astronomical Society when it was founded in 1820. He died in August 1822, and his work was continued by his only son, John Herschel. Uranus Facts - Interesting Facts about Planet Uranus Eris Uranus Facts Uranus is the seventh planet from the Sun . It’s not visible to the naked eye, and became the first planet discovered with the use of a telescope. Uranus is tipped over on its side with an axial tilt of 98 degrees. It is often described as “rolling around the Sun on its side.” 8.68 × 10^25 kg (15 Earths) Moons: 27 ( Miranda , Titania , Ariel, Umbriel & Oberon) Rings: Uranus size compared to Earth Uranus distance from the Sun and orbital eccentricity Facts about Uranus Uranus was officially discovered by Sir William Herschel in 1781. It is too dim to have been seen by the ancients.

At first Herschel thought it was a comet, but several years later it was confirmed as a planet. Herscal tried to have his discovery named “Georgian Sidus” after King George III. The name Uranus was suggested by astronomer Johann Bode. The name comes from the ancient Greek deity Ouranos. Uranus turns on its axis once every 17 hours, 14 minutes. The planet rotates in a retrograde direction, opposite to the way Earth and most other planets turn. Uranus makes one trip around the Sun every 84 Earth years. During some parts of its orbit one or the other of its poles point directly at the Sun and get about 42 years of direct sunlight. The rest of the time they are in darkness. Uranus is often referred to as an “ice giant” planet. Like the other gas giants , it has a hydrogen upper layer, which has helium mixed in. Below that is an icy “mantle, which surrounds a rock and ice core. The upper atmosphere is made of water, ammonia and the methane ice crystals that give the planet its pale blue colour. Uranus hits the coldest temperatures of any planet.

With minimum atmospheric temperature of -224°C Uranus is nearly coldest planet in the solar system. While Neptune doesn’t get as cold as Uranus it is on average colder. The upper atmosphere of Uranus is covered by a methane haze which hides the storms that take place in the cloud decks. Uranus has two sets of very thin dark coloured rings. The ring particles are small, ranging from a dust-sized particles to small boulders. There are eleven inner rings and two outer rings. They probably formed when one or more of Uranus’s moons were broken up in an impact. The first rings were discovered in 1977 with the two outer rings being discovered in Hubble Space Telescope images between 2003 and 2005. Uranus’ moons are named after characters created by William Shakespeare and Alexander Pope. These include Oberon, Titania and Miranda. All are frozen worlds with dark surfaces. Some are ice and rock mixtures. The most interesting Uranian moon is Miranda; it has ice canyons, terraces, and other strange-looking surface areas. Only one spacecraft has flown by Uranus.

In 1986, the Voyager 2 spacecraft swept past the planet at a distance of 81,500 km. It returned the first close-up images of the planet, its moons, and rings. Planet Uranus: Facts About Its Name, Moons and Orbit Planet Uranus: Facts About Its Name, Moons and Orbit By Charles Q. Choi, Space.com Contributor | November 18, 2014 09:17pm ET MORE Uranus’ tilt essentially has the planet orbiting the Sun on its side, the axis of its spin is nearly pointing at the Sun. Credit: NASA and Erich Karkoschka, U. of Arizona Uranus is the seventh planet from the sun and the first to be discovered by scientists. Although Uranus is visible to the naked eye, it was long mistaken as a star because of the planet’s dimness and slow orbit. The planet is also notable for its dramatic tilt, which causes its axis to point nearly directly at the sun.

British astronomer William Herschel discovered Uranus accidentally on March 13, 1781, with his telescope while surveying all stars down to those about 10 times dimmer than can be seen by the naked eye. One "star" seemed different, and within a year Uranus was shown to follow a planetary orbit. Uranuswas named after the Greek sky deity Ouranos, the earliest of the lords of the heavens. It is the only planet to be named after a Greek god rather than a Roman one. Before the name was settled on, many names had been proposed for the new planet , including Hypercronius ("above Saturn"), Minerva (the Roman goddess of wisdom), and Herschel, after its discoverer. To flatter King George III of England, Herschel himself offered Georgium Sidus ("The Georgian Planet") as a name, but that idea was unpopular outside of England and George's native Hanover. German astronomer Johann Bode, who detailed Uranus' orbit, gave the planet its ultimate name. [ Related: How Do You Pronounce 'Uranus'? ] Physical characteristics Uranusis blue-green in color , the result of methane in its mostly hydrogen-helium atmosphere.

The planet is often dubbed an ice giant, since 80 percent or more of its mass is made up of a fluid mix of water, methane, and ammonia ices. Unlike the other planets of the solar system, Uranus is tilted so far that it essentially orbits the sun on its side, with the axis of its spin nearly pointing at the star. This unusual orientation might be due to a collision with a planet-size body, or several small bodies , soon after it was formed. This unusual tilt gives rise to extreme seasons roughly 20 years long, meaning that for nearly a quarter of the Uranian year, equal to 84 Earth-years, the sun shines directly over each pole, leaving the other half of the planet to experience a long, dark, cold winter. The magnetic poles of most planets are typically lined up with the axis along which it rotates, but Uranus' magnetic field is tilted, with its magnetic axis tipped over nearly 60 degrees from the planet's axis of rotation. According to Norman F.

Ness, et al, in an article in the journal Science, this leads to a strangely lopsided magnetic field for Uranus, with the strength of the field at the northern hemisphere's surface being up to more than 10 times that of the strength at the southern hemisphere's surface, affecting the formation of the auroras . Orbital characteristics Average distance from the sun: 1,783,939,400 miles (2,870,972,200 kilometers). By comparison: 19.191 times that of Earth Perihelion (closest approach to the sun): 1,699,800,000 miles (2,735,560,000 km). By comparison: 18.60 times that of Earth Aphelion (farthest distance from sun): 1,868,080,000 miles (3,006,390,000 km).

By comparison: 19.76 times that of Earth Composition & structure Atmospheric composition (by volume): 82.5 percent hydrogen, 15.2 percent helium, 2.3 percent methane Magnetic field: Magnetic pole tilt compared to rotational axis: 58.6 degrees Composition: The overall composition of Uranus is, by mass, thought to be about 25 percent rock, 60 to 70 percent ice, and 5 to 15 percent hydrogen and helium. Internal structure: Mantle of water, ammonia and methane ices; core of iron and magnesium-silicate Orbit & rotation Axial tilt: 97.77 degrees, compared to Earth's 23.5 degrees Seasonal cycle & length: Approximately 21 years per season Orbital period: Approximately 84 Earth years Uranus' climate The extreme axial tilt Uranus experiences can give rise to unusual weather. As sunlight reaches some areas for the first time in years, it heats up the atmosphere, triggering gigantic springtime storms roughly the size of North America, according to NASA.

Ironically, when Voyager 2 first imaged Uranus in 1986 at the height of summer in its south, it saw a bland-looking sphere with only about 10 or so visible clouds, leading to it to be dubbed "the most boring planet," writes astronomer Heidi Hammel in "The Ice Giant Systems of Uranus and Neptune," a chapter in " Solar System Update " (Springer, 2007). It took decades later, when advanced telescopes such as Hubble came into play and the seasons changed, to see extreme weather on Uranus , where fast-moving winds can reach speeds of up to 560 miles (900 kilometers) per hour. The rings of Uranus The rings of Uranus were the first to be seen after Saturn's. They were a significant discovery, because it helped astronomers understand that rings are a common feature of planets, not merely a peculiarity of Saturn. Uranus possesses two sets of rings . The inner system of rings consists mostly of narrow, dark rings, while an outer system of two more-distant rings, discovered by the Hubble Space Telescope, are brightly colored, one red, one blue .

Scientists have now identified 13 known rings around Uranus. Uranus' moons Uranus has 27 known moons . Instead of being named after figures from Greek or Roman mythology, its first four moons were named after magical spirits in English literature, such as William Shakespeare's "A Midsummer Night's Dream" and Alexander Pope's "The Rape of the Lock." Since then, astronomers have continued this tradition, drawing names for the moons from the works of Shakespeare or Pope. Oberon and Titania are the largest Uranian moons, and were the first to be discovered, by Herschel in 1787. William Lassell, who was the first to see a moon orbiting Neptune, discovered the next two, Ariel and Umbriel. Then nearly a century passed before Miranda was found in 1948.

Then, Voyager 2 visited the Uranian system in 1986 and found an additional 10 , all just 16 to 96 miles (26-154 km) in diameter — Juliet, Puck, Cordelia, Ophelia, Bianca, Desdemona, Portia, Rosalind, Cressida and Belinda — and each roughly made half of water ice and half of rock. Since then, astronomers using the Hubble Space Telescope and ground-based observatories have raised the total to 27 known moons, and spotting these was tricky — they are as little as 8 to 10 miles (12 to 16 km) across, blacker than asphalt, and nearly 3 billion miles (4.8 billion km) away. Between Cordelia, Ophelia and Miranda is a swarm of eight small satellites crowded together so tightly that astronomers don't yet understand how the little moons have managed to avoid crashing into each other. Scientists suspect there might still be more moons, closer to Uranus than any known.

In addition to moons, Uranus may also have a collection of Trojan asteroids — objects that share the same orbit as the planet — in a special region known as a Lagrangian point. The first was discovered in 2013 , despite claims that the planet’s Langrangian point would be too unstable to host such bodies. Research & exploration NASA's Voyager 2 was the first and as yet only spacecraft to visit Uranus. It discovered 10 previously unknown moons, and investigated its unusually tilted magnetic field. In 2013, the Planetary Science Decadal Survey recommended NASA consider a mission to the icy planet. Additional reporting by Nola Taylor Redd, Space.com Contributor The butt of solar system jokes, Uranus is also a spectacular blue planet still hiding many scientific secrets. See how much you know: William Herschel Biography William Herschel Biography By Nola Taylor Redd, Space.com Contributor | September 4, 2012 01:51pm ET MORE Scouring the heavens with his sister, Caroline, Sir William Herschel discovered the planet Uranus and several moons around other gas giants.

In the course of his studies of the night sky, he also compiled a catalog of 2,500 celestial objects that is still in use today. But it wasn't until his mid-30s that he began to turn his eyes to the expanse above; he started his professional life as a musician. Astronomer William Herschel discovered the planet Uranus. Credit: Smithsonian Institution A musical beginning Born in Germany as Friedrich Wilhelm Herschel, the astronomer was the son of Anna Ilse Moritzen and Issak Herschel. His father was a military musician, and young William played in the same band in his early years. In 1759, Herschel left Germany for England, where he taught music before becoming an organist. In 1772, William's sister, Caroline, moved to England to live with her brother and train as a singer. During this time, Herschel's interest in astronomy grew significantly. He rented a small telescope, and his desire to own a larger instrument led him to the process of grinding and polishing his own mirrors. Caroline never married, but served as his assistant until Herschel's death.

She was the first woman to discover a comet, ultimately finding eight. She also discovered several deep-sky objects and was the first woman to be given a paid scientific position and to receive an honorary membership into the Royal Society. In 1788, at the age of 50, Herschel married the widow Mary Pitt. Their son, John, was born in 1792, and followed in his father's astronomical footsteps. Searching the skies On March 13, 1781, Herschel noticed a small object that, over the course of several nights, was slowly moving across the sky. At first he thought he had found a comet , but further observation revealed that the object was a planet. Herschel lobbied to name the new body 'Georgium Sidus', after King George III, but it was eventually named Uranus after the Greek god of the sky. As a result of his discovery, the monarch knighted Herschel and appointed him to the position of court astronomer. The attached pension allowed him to conclude his musical career and focus his full attention on the skies.

When Herschel was subsequently elected a member of the prestigious Royal Society, he received a copy of Charles Messier's "Catalog of Nebulae and Star Clusters," a list of diverse nebulae in the night sky. The catalog piqued his interest, and he began to examine the fuzzy objects. On Oct. 23, 1783, he began a sky survey of his own, standing on a ladder while peering through his telescope and describing the objects he saw to his sister, Caroline. By pointing the stationary telescope at a single strip of the sky, he was able to observe east-west bands over the course of the night. The next night, he would adjust his telescope to a higher or lower point and observe another parallel strip. Eventually, he examined the entire swatch of sky that could be seen over Great Britain. Over 20 years, he observed 2,500 new nebulae and star clusters and recorded them in "The General Catalogue of Nebulae." The catalog was eventually enlarged and renamed the "New General Catalogue," and many non-stellar objects are identified by their NGC numbers.

Of the 7,840 nebulae and clusters in the catalog today, 4,630 were discovered by Herschel and his son. In 1789, Herschel finished construction on 40-foot-long (12 meters) telescope, the largest of the day. But the unwieldy instrument came with a number of problems, and Herschel tended to use the smaller, 20-foot (6-meter) telescope. Appearing like a cyclops gazing off into space, Saturn's moon Mimas and its large Herschel Crater are profiled in this view from NASA's Cassini spacecraft taken on Feb. 13, 2010. Credit: NASA/JPL/Space Science Institute Herschel discovered several moons around the gas giants. In 1787, he discovered two moons around Uranus: Titania and Oberon. In 1789, using his larger telescope, he found Saturn' s sixth and seventh moons , Enceladus and Mimas.

[ Meet Mimas: Saturn's Death Star Moon ] In 1800, Herschel performed a simple experiment determining the temperature of the different colors of sunlight passed through a prism. He noticed the region just beyond the red color was even higher than light in the visible spectrum, and used his measurements to deduce the presence of what is now known to be infrared radiation. The European Space Agency's infrared space observatory was subsequently named for him. Herschel proposed the name " asteroids " for the large bodies discovered in 1801. He was elected vice president of the newly formed Royal Astronomical Society in 1820 and president the following year. His last published paper cataloged 145 double stars . Herschel died in England on Aug. 25, 1822, at the age of 84. Craters on the moon, Mars, and Mimas are named for the astronomer. The asteroid 2000 Herschel bears his name, and the symbol for the planet Uranus features the capital letter H in his honor. — Nola Taylor Redd

Question: Who discovered Uranus and one of its moons, Titania, between 1781 and 1787?
Answer: Herschel