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Comet Biela
Biela's Comet or Comet Biela (official designation: 3D/Biela) was a periodic Jupiter-family comet first recorded in 1772 by Montaigne and Messier and finally identified as periodic in 1826 by Wilhelm von Biela. It was subsequently observed to split in two and has not been seen since 1852. As a result, it is currently considered to have been destroyed, although remnants appeared to have survived for some time as a meteor shower, the Andromedids. Discovery The comet was first recorded on 8 March 1772 by Jacques Leibax Montaigne; during the same apparition it was independently discovered by Charles Messier. It was also recorded in 1805 by Jean-Louis Pons, but was not recognized as the same object. After the 1805 apparition a number of attempts were made by Gauss (1806) and Bessel (1806) to calculate a definitive orbit. Gauss and Olbers both noted a similarity between the 1805 and 1772 comets but they were not able to prove a link. Confirmation as periodic It was Wilhelm von ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Comet Halley
Halley's Comet or Comet Halley, officially designated 1P/Halley, is a List of periodic comets, short-period comet visible from Earth every 75–79 years. Halley is the only known short-period comet that is regularly visible to the naked eye from Earth, and thus the only naked-eye comet that can appear twice in a human lifetime. Halley last appeared in the inner parts of the Solar System in 1986 and will next appear in mid-2061. Halley's periodic returns to the inner Solar System have been observed and recorded by astronomers around the world since at least 240 BC. But it was not until 1705 that the English astronomer Edmond Halley understood that these appearances were reappearances of the same comet. As a result of this discovery, the comet is named after Halley. During its 1986 visit to the inner Solar System, Halley's Comet became the first comet to be observed in detail by spacecraft, providing the first observational data on the structure of a comet nucleus and the mecha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arc Minute
A minute of arc, arcminute (arcmin), arc minute, or minute arc, denoted by the symbol , is a unit of angular measurement equal to of one degree. Since one degree is of a turn (or complete rotation), one minute of arc is of a turn. The nautical mile (nmi) was originally defined as the arc length of a minute of latitude on a spherical Earth, so the actual Earth circumference is very near . A minute of arc is of a radian. A second of arc, arcsecond (arcsec), or arc second, denoted by the symbol , is of an arcminute, of a degree, of a turn, and (about ) of a radian. These units originated in Babylonian astronomy as sexagesimal subdivisions of the degree; they are used in fields that involve very small angles, such as astronomy, optometry, ophthalmology, optics, navigation, land surveying, and marksmanship. To express even smaller angles, standard SI prefixes can be employed; the milliarcsecond (mas) and microarcsecond (μas), for instance, are commonly used in astro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Matthew Fontaine Maury
Matthew Fontaine Maury (January 14, 1806February 1, 1873) was an American oceanographer and naval officer, serving the United States and then joining the Confederacy during the American Civil War. He was nicknamed "Pathfinder of the Seas" and is considered a founder of modern oceanography. He wrote extensively on the subject and his book, ''The Physical Geography of the Sea'' (1855), was the first comprehensive work on oceanography to be published. In 1825, at 19, Maury obtained, through US Representative Sam Houston, a midshipman's warrant in the United States Navy. As a midshipman on board the frigate , he almost immediately began to study the seas and record methods of navigation. When a leg injury left him unfit for sea duty, Maury devoted his time to the study of navigation, meteorology, winds, and currents. He became Superintendent of the United States Naval Observatory and head of the Depot of Charts and Instruments. There, Maury studied thousands of ships' logs and cha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Francesco De Vico
Father Francesco de Vico (also known as de Vigo, De Vico and even DeVico; 19 May 1805 in Macerata – 15 November 1848 in London) was an Italian astronomer and a Jesuit priest. Biography He was educated at the college of Urbino, and became in 1835 assistant superintendent, and in 1839 director of the Vatican Observatory. The Revolutions of 1848 in the Italian states cut short his observing career, as he was forced into exile, touring Paris, London, and the United States, where he was received by the President. He was pleased with his reception in the U.S. and wished to settle there at Georgetown College, but first returned to Europe to try to recruit some colleagues to join him and purchase instruments for an observatory to be erected under his direction in New York. Unfortunately, worn out from the travel, he died in London in November of that same year Work He found a remarkable number of comets in a relatively short time, including periodic comets 54P/de Vico-Swift-NEAT and 1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solar Elongation
In astronomy, a planet's elongation is the angular separation between the Sun and the planet, with Earth as the reference point. The greatest elongation of a given inferior planet occurs when this planet's position, in its orbital path around the Sun, is at tangent to the observer on Earth. Since an inferior planet is well within the area of Earth's orbit around the Sun, observation of its elongation should not pose that much a challenge (compared to deep-sky objects, for example). When a planet is at its greatest elongation, it appears farthest from the Sun as viewed from Earth, so its apparition is also best at that point. When an inferior planet is visible after sunset, it is near its greatest eastern elongation. When an inferior planet is visible before sunrise, it is near its greatest western elongation. The angle of the maximum elongation (east or west) for Mercury is between 18° and 28°, while that for Venus is between 45° and 47°. These values vary because the planet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astronomical Unit
The astronomical unit (symbol: au, or or AU) is a unit of length, roughly the distance from Earth to the Sun and approximately equal to or 8.3 light-minutes. The actual distance from Earth to the Sun varies by about 3% as Earth orbits the Sun, from a maximum (aphelion) to a minimum (perihelion) and back again once each year. The astronomical unit was originally conceived as the average of Earth's aphelion and perihelion; however, since 2012 it has been defined as exactly (see below for several conversions). The astronomical unit is used primarily for measuring distances within the Solar System or around other stars. It is also a fundamental component in the definition of another unit of astronomical length, the parsec. History of symbol usage A variety of unit symbols and abbreviations have been in use for the astronomical unit. In a 1976 resolution, the International Astronomical Union (IAU) had used the symbol ''A'' to denote a length equal to the astronomical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Georgios Konstantinos Vouris
Georgios Konstantinos Vouris ( el, Γεώργιος Κωνσταντίνου Βούρης; (1802 - 1860) aka Georg Konstantin Bouris was a Greek astronomer, physicist, mathematician, author, and professor. He was a pioneer in 19th-century Greek astronomy. Vouris lobbied tirelessly to create an astronomical observatory in Athens. He was the first director of the National Observatory of Athens. It was completed in 1846. Greece reconnected with its Astronomical roots. It was the first time since antiquity that a country named Greece played a significant role in Astronomy. He was the first author to publish a university textbook in the field of mathematics since the inception of the new country. He was born in Vienna to Greek parents. He studied astronomy and mathematics with some of the most important scientists of the time namely Andreas von Ettingshausen and Joseph Johann von Littrow. He did significant research in the fields of astrophysics, astronomy, geodesy, meteorology, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
François Arago
Dominique François Jean Arago ( ca, Domènec Francesc Joan Aragó), known simply as François Arago (; Catalan: ''Francesc Aragó'', ; 26 February 17862 October 1853), was a French mathematician, physicist, astronomer, freemason, supporter of the Carbonari revolutionaries and politician. Early life and work Arago was born at Estagel, a small village of 3,000 near Perpignan, in the ' of Pyrénées-Orientales, France, where his father held the position of Treasurer of the Mint. His parents were François Bonaventure Arago (1754–1814) and Marie Arago (1755–1845). Arago was the eldest of four brothers. Jean (1788–1836) emigrated to North America and became a general in the Mexican army. Jacques Étienne Victor (1799–1855) took part in Louis de Freycinet's exploring voyage in the ''Uranie'' from 1817 to 1821, and on his return to France devoted himself to his journalism and the drama. The fourth brother, Étienne Vincent (1802–1892), is said to have collaborated with Ho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Herschel
Sir John Frederick William Herschel, 1st Baronet (; 7 March 1792 – 11 May 1871) was an English polymath active as a mathematician, astronomer, chemist, inventor, experimental photographer who invented the blueprint and did botanical work. Herschel originated the use of the Julian day system in astronomy. He named seven moons of Saturn and four moons of Uranus – the seventh planet, discovered by his father Sir William Herschel. He made many contributions to the science of photography, and investigated colour blindness and the chemical power of ultraviolet rays. His ''Preliminary Discourse'' (1831), which advocated an inductive approach to scientific experiment and theory-building, was an important contribution to the philosophy of science. Early life and work on astronomy Herschel was born in Slough, Buckinghamshire, the son of Mary Baldwin and astronomer William Herschel. He was the nephew of astronomer Caroline Herschel. He studied shortly at Eton College an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thomas Clausen (mathematician)
Thomas Clausen (16 January 1801, Snogbæk, Sottrup Municipality, Duchy of Schleswig (now Denmark) – 23 May 1885, Dorpat, Imperial Russia (now Estonia)) was a Danish mathematician and astronomer. Clausen learned mathematics at home. In 1820, he became a trainee at the Munich Optical Institute and in 1824, at the Altona Observatory after he showed Heinrich Christian Schumacher his paper on calculating longitude by the occultation of stars by the moon. He eventually returned to Munich, where he conceived and published his best known works on mathematics. In 1842 Clausen was hired by the staff of the Tartu Observatory, becoming its director in 1866-1872. Works by Clausen include studies on the stability of Solar System, comet movement, ABC telegraph code and calculation of 250 decimals of pi (later, only 248 were confirmed to be correct). In 1840 he discovered the Von Staudt–Clausen theorem. Also in 1840 he also found two compass and straightedge constructions of lunes w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
