William Herschel
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William Herschel
Frederick William Herschel ( ; ; 15 November 1738 – 25 August 1822) was a German-British astronomer and composer. He frequently collaborated with his younger sister and fellow astronomer Caroline Herschel. Born in the Electorate of Hanover, William Herschel followed his father into the military band of Hanover, before immigrating to Kingdom of Great Britain, 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. Herschel published catalogues of nebulae in 1802 (2,500 objects) and in 1820 (5,000 objects). The resolving power of the Herschel telescopes revealed that many objects called nebulae in the Messier object, Messier catalogue were actually clusters of stars. On 13 March 1781 while making observations he made note of a new object in the constellation of Gemini. This would, after several weeks of verification and consultation with other astrono ...
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Enceladus
Enceladus is the sixth-largest moon of Saturn and the 18th-largest in the Solar System. It is about in diameter, about a tenth of that of Saturn's largest moon, Titan. It is covered by clean, freshly deposited snow hundreds of meters thick, making it one of the most reflective bodies of the Solar System. Consequently, its surface temperature at noon reaches only , far colder than a light-absorbing body would be. Despite its small size, Enceladus has a wide variety of surface features, ranging from old, heavily cratered regions to young, tectonically deformed terrain. Enceladus was discovered on August 28, 1789, by William Herschel, but little was known about it until the two Voyager spacecraft, '' Voyager 1'' and '' Voyager 2'', flew by Saturn in 1980 and 1981. In 2005, the spacecraft '' Cassini'' started multiple close flybys of Enceladus, revealing its surface and environment in greater detail. In particular, ''Cassini'' discovered water-rich plumes venting fro ...
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Mimas (moon)
Mimas, also designated Saturn I, is the seventh-largest natural satellite of Saturn. With a mean diameter of , Mimas is the smallest astronomical body known to be roughly rounded in shape due to its own gravity. Mimas's low density, 1.15 g/cm3, indicates that it is composed mostly of water ice with only a small amount of rock, and study of Mimas's motion suggests that it may have a liquid ocean beneath its surface ice. The surface of Mimas is heavily cratered and shows little signs of recent geological activity. A notable feature of Mimas's surface is Herschel, one of the largest craters relative to the size of the parent body in the Solar System. Herschel measures across, about one-third of Mimas's mean diameter, and formed from an extremely energetic impact event. The crater's name is derived from the discoverer of Mimas, William Herschel, in 1789. The moon's presence has created one of the largest 'gaps' in Saturn's ring, named the Cassini Division, due to orbital ...
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Uranus
Uranus is the seventh planet from the Sun. It is a gaseous cyan-coloured ice giant. Most of the planet is made of water, ammonia, and methane in a Supercritical fluid, supercritical phase of matter, which astronomy calls "ice" or Volatile (astrogeology), volatiles. Atmosphere of Uranus, The planet's atmosphere has a complex layered cloud structure and has the lowest minimum temperature () of all the Solar System's planets. It has a marked axial tilt of 82.23° with a Retrograde and prograde motion, retrograde rotation period of 17 hours and 14 minutes. This means that in an 84-Earth-year orbital period around the Sun, its poles get around 42 years of continuous sunlight, followed by 42 years of continuous darkness. Uranus has the third-largest diameter and fourth-largest mass among the Solar System's planets. Based on current models, inside its volatile Mantle (geology), mantle layer is a rocky core, and surrounding it is a thick hydrogen and helium atmosphere. Trace amount ...
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Lemuel Francis Abbott
Lemuel "Francis" Abbott (1760/61 – 5 December 1803) was an English Portrait painting, portrait painter, famous for his painting of Horatio Nelson, 1st Viscount Nelson (currently hanging in the Terracotta Room of number 10 Downing Street) and for those of other Royal Navy, naval officers and British literature, literary figures of the 18th century in literature, 18th century. Life He was born Lemuel Abbott in Leicestershire in 1760 or 1761, the son of clergyman Lemuel Abbott, curate of Anstey, Leicestershire, Anstey (and later vicar of Thornton, Leicestershire, Thornton) and his wife Mary.Nisbet, Archibald (2004)Abbott, Lemuel Francis [Samuel] (1760/1761-1802), portrait painter, ''Oxford Dictionary of National Biography'', . Retrieved 23 November 2014 In 1775, at the age of 14, he became a pupil of Francis Hayman and lived in London, but returned to his parents after his teacher's death in 1776. There he continued to develop his artistic talents independently, but some ...
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Nebula
A nebula (; or nebulas) is a distinct luminescent part of interstellar medium, which can consist of ionized, neutral, or molecular hydrogen and also cosmic dust. Nebulae are often star-forming regions, such as in the Pillars of Creation in the Eagle Nebula. In these regions, the formations of gas, dust, and other materials "clump" together to form denser regions, which attract further matter and eventually become dense enough to form stars. The remaining material is then thought to form planets and other planetary system objects. Most nebulae are of vast size; some are hundreds of light-years in diameter. A nebula that is visible to the human eye from Earth would appear larger, but no brighter, from close by. The Orion Nebula, the brightest nebula in the sky and occupying an area twice the angular diameter of the full Moon, can be viewed with the naked eye but was missed by early astronomers. Although denser than the space surrounding them, most nebulae are far less dens ...
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Pirna
Pirna (; , ) is a town in Saxony, Germany and capital of the administrative district Sächsische Schweiz-Osterzgebirge. The town's population is over 37,000. Pirna is located near Dresden and is an important district town as well as a ''Große Kreisstadt''. Geography Geographical location Pirna is located in the vicinity of the Elbe Sandstone Mountains, Sandstone Mountains in the upper Elbe valley, where two nearby tributaries, Wesenitz from the north and Gottleuba from the south, flow into the Elbe. It is also called the "gate to the Saxon Switzerland" (German language, Ger: ''Tor zur Sächsischen Schweiz''). The Saxony (wine region), Saxon wine region (German language, Ger: ''Sächsische Weinstraße''), which was established in 1992, stretches from Pirna via Pillnitz, Dresden, and Meissen to Diesbar-Seußlitz. Neighboring municipalities Pirna is located southeast of Dresden. Neighboring municipalities are Bad Gottleuba-Berggießhübel (town), Bahretal, Dohma, Dohna ( ...
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Royal Guelphic Order
The Royal Guelphic Order (), sometimes referred to as the Hanoverian Guelphic Order, is a Kingdom of Hanover, Hanoverian order of chivalry instituted on 28 April 1815 by the Prince Regent (later King George IV). It takes its name from the House of Guelph, of which the House of Hanover was a branch. Since Hanover and the United Kingdom personal union, shared a monarch until 1837, the order was frequently bestowed upon British subjects. History Until 1837 the order was frequently awarded to officers in the British Royal Navy, Navy and British Army, Army, although it was still classed as a foreign order, with British members of the order not entitled to style themselves as "Sir" unless they were also created Knights Bachelor, as many were. The British link ended in 1837 when Kingdom of Hanover, Hanover's royal union with Great Britain ended, with Ernest Augustus, King of Hanover, Ernest Augustus becoming King of Hanover and Queen Victoria ascending the British throne. When Hanover ...
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Saturn
Saturn is the sixth planet from the Sun and the second largest in the Solar System, after Jupiter. It is a gas giant, with an average radius of about 9 times that of Earth. It has an eighth the average density of Earth, but is over 95 times more massive. Even though Saturn is almost as big as Jupiter, Saturn has less than a third its mass. Saturn orbits the Sun at a distance of , with an orbital period of 29.45 years. Saturn's interior is thought to be composed of a rocky core, surrounded by a deep layer of metallic hydrogen, an intermediate layer of liquid hydrogen and liquid helium, and an outer layer of gas. Saturn has a pale yellow hue, due to ammonia crystals in its upper atmosphere. An electrical current in the metallic hydrogen layer is thought to give rise to Saturn's planetary magnetic field, which is weaker than Earth's, but has a magnetic moment 580 times that of Earth because of Saturn's greater size. Saturn's magnetic field strength is about a twen ...
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Oberon (moon)
Oberon , also designated , 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-largest 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. Oberon likely formed from the accretion disk that surrounded Uranus just after the planet's formation. The moon consists of approximately equal amounts of ice and rock, and is probably differentiated into a rocky core and an icy mantle. A layer of liquid water may be present at the boundary between the mantle and the core. The surface of Oberon, which is dark and slightly red in color, appears to have been primarily shaped by asteroid and comet impacts. It is covered by numerous impact craters reaching 210 km in diameter. Oberon possesses a system of ' ...
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Titania (moon)
Titania (), also designated Uranus III, is the largest moon of Uranus. At a diameter of it is the List of natural satellites by diameter, 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 Titania (A Midsummer Night's Dream), queen of the fairies in Shakespeare's ''A Midsummer Night's Dream''. Its orbit lies inside Uranus's magnetosphere. Titania consists of approximately equal amounts of ice and rock (geology), rock, and is probably differentiated into a rocky core (geology), core and an icy mantle (geology), mantle. A layer of liquid water may be present at the core–mantle boundary. Its surface, which is relatively dark and slightly red in color, appears to have been shaped by both impacts and endogenic processes. It is covered with numerous impact craters reaching up to in diameter, but is less heavily cratered than Oberon (moon), Oberon, outermost of the five large mo ...
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Mars
Mars is the fourth planet from the Sun. It is also known as the "Red Planet", because of its orange-red appearance. Mars is a desert-like rocky planet with a tenuous carbon dioxide () atmosphere. At the average surface level the atmospheric pressure is a few thousandths of Earth's, atmospheric temperature ranges from and cosmic radiation is high. Mars retains some water, in the ground as well as thinly in the atmosphere, forming cirrus clouds, frost, larger polar regions of permafrost and ice caps (with seasonal snow), but no liquid surface water. Its surface gravity is roughly a third of Earth's or double that of the Moon. It is half as wide as Earth or twice the Moon, with a diameter of , and has a surface area the size of all the dry land of Earth. Fine dust is prevalent across the surface and the atmosphere, being picked up and spread at the low Martian gravity even by the weak wind of the tenuous atmosphere. The terrain of Mars roughly follows a north-south ...
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Infrared
Infrared (IR; sometimes called infrared light) is electromagnetic radiation (EMR) with wavelengths longer than that of visible light but shorter than microwaves. The infrared spectral band begins with the waves that are just longer than those of red light (the longest waves in the visible spectrum), so IR is invisible to the human eye. IR is generally (according to ISO, CIE) understood to include wavelengths from around to . IR is commonly divided between longer-wavelength thermal IR, emitted from terrestrial sources, and shorter-wavelength IR or near-IR, part of the solar spectrum. Longer IR wavelengths (30–100 μm) are sometimes included as part of the terahertz radiation band. Almost all black-body radiation from objects near room temperature is in the IR band. As a form of EMR, IR carries energy and momentum, exerts radiation pressure, and has properties corresponding to both those of a wave and of a particle, the photon. It was long known that fires e ...
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