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Bubble Sextant
The bubble octant and bubble sextant are air navigation instruments. Although an instrument is called a "bubble sextant", it may actually be a bubble octant. Use Ships had long used sextants for navigation, but sextants had problems in aircraft navigation. A ship at sea is on a relatively flat surface and can use the horizon to measure the altitude of celestial objects. An aircraft may not have the sea's horizon as a flat reference surface. It may be flying over land where the horizon is formed by mountains of unknown height. A solution to the problem was to use a bubble to determine the reference plane. The bubble in an airplane is subject to the plane's acceleration. If the plane is in sharp turn, the bubble will be displaced. Consequently, when the navigator is using a bubble sextant, the pilot tries to fly the plane straight and level. Even when flying straight and level, the plane is subject to accelerations from density and wind changes. Consequently, many readings are ta ...
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Sextant
A sextant is a doubly reflecting navigation instrument that measures the angular distance between two visible objects. The primary use of a sextant is to measure the angle between an astronomical object and the horizon for the purposes of celestial navigation. The estimation of this angle, the altitude, is known as ''sighting'' or ''shooting'' the object, or ''taking a sight''. The angle, and the time when it was measured, can be used to calculate a position line on a nautical or aeronautical chart—for example, sighting the Sun at noon or Polaris at night (in the Northern Hemisphere) to estimate latitude (with sight reduction). Sighting the height of a landmark can give a measure of ''distance off'' and, held horizontally, a sextant can measure angles between objects for a position on a chart. A sextant can also be used to measure the lunar distance between the moon and another celestial object (such as a star or planet) in order to determine Greenwich Mean Time and hence ...
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Isaac Newton
Sir Isaac Newton (25 December 1642 – 20 March 1726/27) was an English mathematician, physicist, astronomer, alchemist, theologian, and author (described in his time as a "natural philosopher"), widely recognised as one of the greatest mathematicians and physicists and among the most influential scientists of all time. He was a key figure in the philosophical revolution known as the Enlightenment. His book (''Mathematical Principles of Natural Philosophy''), first published in 1687, established classical mechanics. Newton also made seminal contributions to optics, and shares credit with German mathematician Gottfried Wilhelm Leibniz for developing infinitesimal calculus. In the , Newton formulated the laws of motion and universal gravitation that formed the dominant scientific viewpoint for centuries until it was superseded by the theory of relativity. Newton used his mathematical description of gravity to derive Kepler's laws of planetary motion, account for ...
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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 used ...
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Octant (instrument)
The octant, also called a reflecting quadrant (instrument), quadrant, is a reflecting instrument used in navigation. Etymology The name ''octant'' derives from the Latin ''octans'' meaning ''eighth part of a circle'', because the instrument's arc is one eighth of a circle. ''Reflecting quadrant'' derives from the instrument using mirrors to reflect the path of light to the observer and, in doing so, doubles the angle measured. This allows the instrument to use a one-eighth of a Turn (geometry), turn to measure a quarter-Turn (geometry), turn or Circular sector, quadrant. Origin of the octant Newton's reflecting quadrant Isaac Newton's reflecting quadrant was invented around 1699. A detailed description of the instrument was given to Edmond Halley, but the description was not published until after Halley's death in 1742. It is not known why Halley did not publish the information during his life, as this prevented Newton from getting the credit for the invention that is gene ...
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Amelia Earhart
Amelia Mary Earhart ( , born July 24, 1897; disappeared July 2, 1937; declared dead January 5, 1939) was an American aviation pioneer and writer. Earhart was the first female aviator to fly solo across the Atlantic Ocean. She set many other records, was one of the first aviators to promote commercial air travel, wrote best-selling books about her flying experiences, and was instrumental in the formation of The Ninety-Nines, an organization for female pilots. Born and raised in Atchison, Kansas, and later in Des Moines, Iowa, Earhart developed a passion for adventure at a young age, steadily gaining flying experience from her twenties. In 1928, Earhart became the first female passenger to cross the Atlantic by airplane (accompanying pilot Wilmer Stultz), for which she achieved celebrity status. In 1932, piloting a Lockheed Vega 5B, Earhart made a nonstop solo transatlantic flight, becoming the first woman to achieve such a feat. She received the United States Distinguish ...
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Fred Noonan
Frederick Joseph "Fred" Noonan (born April 4, 1893 – disappeared July 2, 1937, declared dead June 20, 1938) was an American flight navigator, sea captain and aviation pioneer, who first charted many commercial airline routes across the Pacific Ocean during the 1930s. Navigator for Amelia Earhart, they disappeared somewhere over the Central Pacific Ocean, on July 2, 1937 during one of the last legs of their attempted pioneering round-the-world flight. Early life Fred Noonan was born in Cook County, Illinois to Joseph T. Noonan (born Lincolnville, Maine, in 1861) and Catherine Egan (born London, England), both of Irish descent. Noonan's mother died when he was four, and three years later a census report lists his father as living alone in a Chicago boarding house. Relatives or family friends were likely looking after Noonan. In his own words, Noonan "left school in summer of 1905 and went to Seattle, Washington,"
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Eddie Rickenbacker
Edward Vernon Rickenbacker or Eddie Rickenbacker (October 8, 1890 – July 23, 1973) was an American fighter pilot in World War I and a Medal of Honor recipient.Edward Vernon Rickenbacke
." ''Encyclopedia Britannica'', July 19, 2022.
With 26 aerial victories, he was the most successful and most decorated United States of the war. He was also a race car driver, an automotive designer, and a long-time head of Eastern Air Lines.


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Bausch And Lomb
Bausch + Lomb is an eye health products company based in Vaughan, Ontario, Canada. It is one of the world's largest suppliers of contact lenses, lens care products, pharmaceuticals, intraocular lenses, and other eye surgery products. The company was founded in Rochester, New York, in 1853 by optician John Bausch and cabinet maker turned financial backer Henry Lomb. Until its sale in 2013, Bausch + Lomb was one of the oldest continually operating companies in the United States. Bausch + Lomb was a public company listed on the NYSE, until it was acquired by private equity firm Warburg Pincus in 2007. In May 2013, Canadian-based Valeant Pharmaceuticals announced that it would acquire Bausch + Lomb from Warburg Pincus for $4.5 billion in cash. The deal, which was approved by shareholders, closed on August 5, 2013. On May 6, 2022, the company completed an initial public offering and again became publicly traded. Today, the company employs about 21,000 people and manufactures and m ...
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Air Navigation
The basic principles of air navigation are identical to general navigation, which includes the process of planning, recording, and controlling the movement of a craft from one place to another. Successful air navigation involves piloting an aircraft from place to place without getting lost, not breaking the laws applying to aircraft, or endangering the safety of those on board or on the ground. Air navigation differs from the navigation of surface craft in several ways; Aircraft travel at relatively high speeds, leaving less time to calculate their position en route. Aircraft normally cannot stop in mid-air to ascertain their position at leisure. Aircraft are safety-limited by the amount of fuel they can carry; a surface vehicle can usually get lost, run out of fuel, then simply await rescue. There is no in-flight rescue for most aircraft. Additionally, collisions with obstructions are usually fatal. Therefore, constant awareness of position is critical for aircraft pilots. The ...
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Celestial Navigation
Celestial navigation, also known as astronavigation, is the practice of position fixing using stars and other celestial bodies that enables a navigator to accurately determine their actual current physical position in space (or on the surface of the Earth) without having to rely solely on estimated positional calculations, commonly known as "dead reckoning", made in the absence of satellite navigation or other similar modern electronic or digital positioning means. Celestial navigation uses "sights", or timed angular measurements, taken typically between a celestial body (e.g. the Sun, the Moon, a planet, or a star) and the visible horizon. Celestial navigation can also take advantage of measurements between celestial bodies without reference to the Earth horizon, such as when the Moon and other selected bodies are used in the practice called "lunars" or lunar distance method, used for determining precise time when time is unknown. Celestial navigation by taking sights of the ...
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