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Quadrant (instrument)
A quadrant is an instrument used to measure angles up to 90°. Different versions of this instrument could be used to calculate various readings, such as longitude, latitude, and time of day. Its earliest recorded usage was in ancient India in Rigvedic times by Rishi Atri to observe a solar eclipse. It was then proposed by Ptolemy as a better kind of astrolabe. Several different variations of the instrument were later produced by medieval Muslim astronomers. Mural quadrants were important astronomical instruments in 18th-century European observatories, establishing a use for positional astronomy. Etymology The term ''quadrant'', meaning one fourth, refers to the fact that early versions of the instrument were derived from astrolabes. The quadrant condensed the workings of the astrolabe into an area one fourth the size of the astrolabe face; it was essentially a quarter of an astrolabe. History During Rigvedic times in ancient India, quadrants called 'Tureeyam's were u ...
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Ancient Beijing Observatory 14
Ancient history is a time period from the beginning of writing and recorded human history to as far as late antiquity. The span of recorded history is roughly 5,000 years, beginning with the Sumerian cuneiform script. Ancient history covers all continents inhabited by humans in the period 3000 BCAD 500. The three-age system periodizes ancient history into the Stone Age, the Bronze Age, and the Iron Age, with recorded history generally considered to begin with the Bronze Age. The start and end of the three ages varies between world regions. In many regions the Bronze Age is generally considered to begin a few centuries prior to 3000 BC, while the end of the Iron Age varies from the early first millennium BC in some regions to the late first millennium AD in others. During the time period of ancient history, the world population was already exponentially increasing due to the Neolithic Revolution, which was in full progress. While in 10,000 BC, the world population stood ...
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Quadrant Pivotant
Quadrant may refer to: Companies * Quadrant Cycle Company, 1899 manufacturers in Britain of the Quadrant motorcar * Quadrant (motorcycles), one of the earliest British motorcycle manufacturers, established in Birmingham in 1901 * Quadrant Private Equity, an Australian investment firm * Quadrant Records, an independent record label * Quadrant Televentures Ltd., a subsidiary of Videocon Telecom, India Geography * A quadrant or section in a city street nomenclature system, see Address (geography)#Quadrants * Quadrants of Washington, D.C. Mathematics * Quadrant (circle), a circular sector equal to one quarter of a circle, or half a semicircle * Quadrant (plane geometry), a sector of a two-dimensional Cartesian coordinate system * Quadrant (solid geometry) Military * , a Second World War British/Australian warship * First Quebec Conference, 1943 (codenamed "QUADRANT") Science and technology * Galactic quadrant, one out of four circular sectors in the division of the Milky Way ...
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Christopher Clavius
Christopher Clavius, SJ (25 March 1538 – 6 February 1612) was a Jesuit German mathematician, head of mathematicians at the Collegio Romano, and astronomer who was a member of the Vatican commission that accepted the proposed calendar invented by Aloysius Lilius, that is known as the Gregorian calendar. Clavius would later write defences and an explanation of the reformed calendar, including an emphatic acknowledgement of Lilius' work. In his last years he was probably the most respected astronomer in Europe and his textbooks were used for astronomical education for over fifty years in and even out of Europe. Early life Little is known about Clavius' early life other than the fact that he was born in Bamberg in either 1538 or 1537. His given name is not known to any great degree of certainty—it is thought by scholars to have perhaps been ''Christoph Clau'' or ''Klau''. There are also some who think that his taken name, ''Clavius'', may be a Latinization of his original G ...
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Copernicus
Nicolaus Copernicus (; pl, Mikołaj Kopernik; gml, Niklas Koppernigk, german: Nikolaus Kopernikus; 19 February 1473 – 24 May 1543) was a Renaissance polymath, active as a mathematician, astronomer, and Catholic canon, who formulated a model of the universe that placed the Sun rather than Earth at its center. In all likelihood, Copernicus developed his model independently of Aristarchus of Samos, an ancient Greek astronomer who had formulated such a model some eighteen centuries earlier. The publication of Copernicus's model in his book ' (''On the Revolutions of the Celestial Spheres''), just before his death in 1543, was a major event in the history of science, triggering the Copernican Revolution and making a pioneering contribution to the Scientific Revolution. Copernicus was born and died in Royal Prussia, a region that had been part of the Kingdom of Poland since 1466. A polyglot and polymath, he obtained a doctorate in canon law and was a mathematician, ...
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Jacob Ben Machir Ibn Tibbon
Jacob ben Machir ibn Tibbon ( he, יעקב בן מכיר ׳ן תיבון), of the Ibn Tibbon family, also known as Prophatius, was a Jewish astronomer; born, probably at Marseilles, about 1236; died at Montpellier about 1304. He was a grandson of Samuel ben Judah ibn Tibbon. His Provençal name was Don Profiat Tibbon; the Latin writers called him Profatius Judæus. Jacob occupies a considerable place in the history of astronomy in the Middle Ages. His works, translated into Latin, were quoted by Copernicus, Reinhold, and Clavius. He was also highly reputed as a physician, and, according to Jean Astruc ("Mémoires pour Servir à l'Histoire de la Faculté de Médecine de Montpellier," p. 168), Ibn Tibbon was regent of the faculty of medicine of Montpellier. In the controversy between the Maimonists and the anti-Maimonists, Jacob defended science against the attacks of Abba Mari and his party; the energetic attitude of the community of Montpellier on that occasion was due to ...
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House Of Wisdom
The House of Wisdom ( ar, بيت الحكمة, Bayt al-Ḥikmah), also known as the Grand Library of Baghdad, refers to either a major Abbasid public academy and intellectual center in Baghdad or to a large private library belonging to the Abbasid caliphs during the Islamic Golden Age. The House of Wisdom was founded either as a library for the collections of the Caliph Harun al-Rashid in the late 8th century (then later turned into a public academy during the reign of al-Ma'mun) or was a private collection created by al-Mansur (reign 754–775) to house rare books and collections of poetry in Arabic. The House of Wisdom and its contents were destroyed in the Siege of Baghdad in 1258, leaving relatively limited archaeological evidence for the House of Wisdom, such that most knowledge about it is derived from the works of contemporary scholars of the era such as al-Tabari and Ibn al-Nadim. Background The House of Wisdom existed as a part of the major Translation Movement t ...
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Muhammad Ibn Musa Al-Khwarizmi
Muḥammad ibn Mūsā al-Khwārizmī ( ar, محمد بن موسى الخوارزمي, Muḥammad ibn Musā al-Khwārazmi; ), or al-Khwarizmi, was a Persians, Persian polymath from Khwarazm, who produced vastly influential works in Mathematics in medieval Islam, mathematics, Astronomy in the medieval Islamic world, astronomy, and Geography and cartography in medieval Islam, geography. Around 820 CE, he was appointed as the astronomer and head of the library of the House of Wisdom in Baghdad.Maher, P. (1998), "From Al-Jabr to Algebra", ''Mathematics in School'', 27(4), 14–15. Al-Khwarizmi's popularizing treatise on algebra (''The Compendious Book on Calculation by Completion and Balancing'', c. 813–833 CEOaks, J. (2009), "Polynomials and Equations in Arabic Algebra", ''Archive for History of Exact Sciences'', 63(2), 169–203.) presented the first systematic solution of linear equation, linear and quadratic equations. One of his principal achievements in algebra was his demon ...
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Sine Quadrant
250px, Sinecal Quadrant or as it is known in Arabic: Rub‘ul mujayyab The sine quadrant (Arabic: , ), sometimes known as the "sinecal quadrant", was a type of quadrant used by medieval Arabic astronomers. The instrument could be used to measure celestial angles, to tell time, to find directions, to perform trigonometric computations, or to determine the apparent positions of any celestial object for any time. The name is derived from the Arabic meaning 'a quarter' and meaning 'marked with sine'. It was described by Muhammad ibn Mūsā al-Khwārizmī in 9th-century Baghdad, and was used throughout the medieval Islamic period to determine the proper times for Islamic prayer.David A. King, "Islamic Astronomy", in Christopher Walker (1999), ed., Astronomy before the telescope, p. 167-168. British Museum Press. . Description The instrument is a quarter of a circle made of wood or metal (usually brass) divided on its arc side into 90 equal parts or degrees. The 90 divisions ...
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Samarkand
fa, سمرقند , native_name_lang = , settlement_type = City , image_skyline = , image_caption = Clockwise from the top:Registan square, Shah-i-Zinda necropolis, Bibi-Khanym Mosque, view inside Shah-i-Zinda, Sher-Dor Madrasah in Registan, Timur's Mausoleum Gur-e-Amir. , image_alt = , image_flag = , flag_alt = , image_seal = Emblem of Samarkand.svg , seal_alt = , image_shield = , shield_alt = , etymology = , nickname = , motto = , image_map = , map_alt = , map_caption = , pushpin_map = Uzbekistan#West Asia#Asia , pushpin_map_alt = , pushpin_mapsize = 300 , pushpin_map_caption = Location in Uzbekistan , pushpin_label_position = , pushpin_relief = 1 , coordinates = , coor_pinpoint = , co ...
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Rey, Iran
Shahr-e Ray ( fa, شهر ری, ) or simply Ray (Shar e Ray; ) is the capital of Ray County in Tehran Province, Iran. Formerly a distinct city, it has now been absorbed into the metropolitan area of Greater Tehran as the 20th district of municipal Tehran, the capital city of the country. Historically known as Rhages (), Rhagae and Arsacia, Ray is the oldest existing city in Tehran Province. In the classical era, it was a prominent city belonging to Media, the political and cultural base of the Medes. Ancient Persian inscriptions and the Avesta (Zoroastrian scriptures), among other sources, attest to the importance of ancient Ray. Ray is mentioned several times in the Apocrypha. It is also shown on the fourth-century Peutinger Map. The city was subject to severe destruction during the medieval invasions by the Arabs, Turks, and Mongols. Its position as a capital city was revived during the reigns of the Buyid Daylamites and the Seljuk Turks. Ray is richer than many other anc ...
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Maragheh Observatory
The Maragheh observatory (Persian: رصدخانه مراغه), also spelled Maragha, Maragah, Marageh, and Maraga, was an astronomical observatory established in the mid 13th century under the patronage of the Ilkhanid Hulagu and the directorship of Nasir al-Din al-Tusi, a Persian scientist and astronomer. The observatory is located on the west side of Maragheh, which is situated in today's East Azerbaijan Province of Iran.Niri, J. S. (2017). Determine the function and design of architectural and astronomical ... Determine the Function and Design of Architectural and Astronomical Observatory Discovered in the Maragheh. Retrieved November 8, 2022, from https://www.researchgate.net/publication/349064264_Determine_the_Function_and_Design_of_Architectural_and_Astronomical_Observatory_Discovered_in_the_Maragheh It was considered one of the most advanced scientific institutions in Eurasia because it was a center for many groundbreaking calculations in mathematics and astronomy, it hous ...
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