View source for Template:Selected anniversaries/August 21

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File:Tycho Brahe.jpg|link=Tycho Brahe (nonfiction)|1560: The occurrence at the predicted time of a solar eclipse in Copenhagen turns [[Tycho Brahe (nonfiction)|Tycho Brahe]] towards a life of observational astronomy.

||1614: Elizabeth Báthory dies ... aristocrat and serial killer. Pic.

File:Hubert Gautier.jpg|link=Hubert Gautier (nonfiction)|1660: Physician, mathematician, and engineer [[Hubert Gautier (nonfiction)|Hubert Gautier]] born. Gautier will author the first book on bridge building, ''Traité des Ponts'', in 1716, as well as books on roads, fortifications, antiquities, geology, and a first manual for watercolor practitioners.

||1665: Giacomo F. Maraldi born ... astronomer and mathematician. ... discovery ... the ice caps on Mars are not exactly on the rotational poles of that body. Maraldi is also credited for the first observation (1723) of what is usually referred to as Poisson's spot, an observation that was unrecognized until its rediscovery in the early 19th century by Dominique Arago. At the time of Arago's discovery, Poisson's spot gave convincing evidence for the contested wave nature of light. No pic online: https://www.google.com/search?q=Giacomo+F.+Maraldi

||1673: Reinier de Graaf dies ... physician who discovered the follicles of the ovary (known as Graafian follicles), in which the individual egg cells are formed (1672) and also published on male reproductive organs (1668). He was also important for his studies on pancreatic juice (1663) and on the reproductive organs of mammals. He is considered one of the creators of experimental physiology. He used a technique of injecting dye into organs in order to be able to observe them better. It was on this technique that a bitter priority dispute with Swammerdam developed. He wrote a brief tract on the use of the syringe in anatomy (1669). He died, perhaps by suicide, at only 32 years of age. Pic.

||1754: William Murdoch born ... engineer and inventor, created gas lighting. Pic.

||1762: Lady Mary Wortley Montagu dies ... was an English aristocrat, letter writer and poet. Lady Mary is today chiefly remembered for her letters, particularly her letters from travels to the Ottoman Empire, as wife to the British ambassador to Turkey, which have been described by Billie Melman as "the very first example of a secular work by a woman about the Muslim Orient". Aside from her writing, Lady Mary is also known for introducing and advocating for smallpox inoculation to Britain after her return from Turkey.  Pic.

||1789: Augustin-Louis Cauchy born ... mathematician and academic. Pic.

||1813: Jean Servais Stas born ... chemist, notable for his accurate determinations of atomic weights. He had worked under the direction of Dumas, with whom he established the atomic weight of carbon. Stas worked assiduously to make more accurate measurements of other atomic weights than had ever been done before. Stas wished to prove the hypothesis of Joseph Proust, that all atoms were conglomerations of hydrogen atoms, though this could not be achieved. Stas was probably the most skillful chemical analyst of the nineteenth century. Pic.

||1814: Benjamin Thompson Rumford dies ... physicist, government administrator, and a founder of the Royal Institution of Great Britain, London. Because he was a Redcoat officer and an English spy during the American revolution, he moved into exile in England. Through his investigations of heat he became one of the first scientists to declare that heat is a form of motion rather than a material substance, as was popularly believed until the mid-19th century. Among his numerous scientific contributions are the development of a calorimeter and a photometer. He invented a double boiler, a kitchen stove and a drip coffee pot. Pic.

||1816: Charles Frédéric Gerhardt born ... chemist. Pic.

||1826: Karl Gegenbaur born ... anatomist and professor who demonstrated that the field of comparative anatomy offers important evidence supporting of the theory of evolution. From studies in embryology, he asserted that all eggs are simple cells (1861) as suggested earlier by Schwann (1838). Pic.

||1836: Claude-Louis Navier dies ... physicist and engineer. Pic: bust.

|File:Wizard Jan Kochanowski.jpg|link=Jan_Kochanowski|1872: Poet and wizard [[Jan Kochanowski]] adapts [[Nebra sky disk (nonfiction)|Nebra sky disk]] for use as [[scrying engine]].

||1888: The first successful adding machine in the United States is patented by William Seward Burroughs. ...  William Seward Burroughs of St. Louis, Missouri, received patents on four adding machine applications (No. 388,116-388,119), the first U.S. patents for a "Calculating-Machine" that the inventor would continue to improve and successfully market. One year after making his first patent application on 10 Jan 1885, he incorporated his business as the American Arithmometer Corporation of St. Louis, in Jan 1886, with an authorized capitalization of $100,000. After Burrough's early death in 1898, after moving from St. Louis to Detroit, Michigan, that company reorganized as the Burroughs Adding Machine Co., incorporated in Jan 1905, with a capital of $5 million. 

||1901: Adolf Eugen Fick dies ... physiologist who made several physiological measurment devices, including the first practical opthalmotonometer for the measurement of intraocular pressure. He developed fundamental laws of diffusion in living organisms (published in Die medizinische Physik, 1856) and is remembered for Fick's Law which enables calculation of the cardiac output. Pic.

||1901: Edward Copson born ... mathematician known for his studies in classical analysis, differential and integral equations, and their use in mathematical physics. After graduating from Oxford University with a B.A. degree in 1922, he moved to Scotland where he spent the nearly all of his career. His first book, The Theory of Functions of a Complex Variable (1935) was immediately successful. He was a co-author for his next book, The Mathematical Theory of Huygens' Principle (1939). By 1975, he had published four more books, on asymptotic expansions, metric spaces and partial differential equations. Many of the papers he wrote bridged mathematics and physics, of which his last showed his interest in astrophysics, Electrostatics in a Gravitational Field (1978) which was relevant to Black Holes. Pic: https://ro.wikipedia.org/wiki/Edward_Thomas_Copson http://www-history.mcs.st-and.ac.uk/PictDisplay/Copson.html

File:Nikolay_Bogolyubov.jpg|link=Nikolay Bogolyubov (nonfiction)|1909: Mathematician and physicist [[Nikolay Bogolyubov (nonfiction)|Nikolay Bogolyubov]] born. His method of teaching, based on creation of a warm atmosphere, politeness, and kindness, will be renowned in Russia as the "Bogolyubov approach".

File:Subrahmanyan Chandrasekhar.png|link=Subrahmanyan Chandrasekhar (nonfiction)|1910: Astrophysicist, astronomer, and mathematician [[Subrahmanyan Chandrasekhar (nonfiction)|Subrahmanyan Chandrasekhar]] born. He will share the 1983 Nobel Prize for Physics "for his theoretical studies of the physical processes of importance to the structure and evolution of the stars". 

||1910: Mathematician Ted Youngs born. Youngs worked in geometric topology; he is famous for the Ringel–Youngs theorem which proved the Heawood conjecture, a problem closely related to the Four color theorem for surfaces of higher genus. Pic search.

||1911: The Mona Lisa is stolen by a Louvre employee.

File:Robert_Furman.jpg|link=Robert Furman (nonfiction)|1915: Engineer and American intelligence officer [[Robert Furman (nonfiction)|Robert Furman]] born. Furman will be chief of foreign intelligence for the [[Manhattan Project (nonfiction)|Manhattan Project]], directing espionage against the German nuclear energy project, and, near the end of the war, rounding up German atomic scientists.

||1916: Engineer Hans-Georg Münzberg born ... specialized in airplane turbines and space flight. He taught at the TU Berlin, the TH Munich, and wrote textbooks. Pic search.

||1918: Bruria Kaufman born ... theoretical physicist. She is known for contributions to Albert Einstein's general theory of relativity, to statistical physics, where she used applied spinor analysis to rederive the result of Lars Onsager on the partition function of the two-dimensional Ising Model, and to the study of the Mössbauer effect, on which she collaborated with John von Neumann and Harry Lipkin. Pic.

||1927: William Burnside dies ... mathematician. He is known mostly as an early researcher in the theory of finite groups. Pic.

||1933: Leon Lichtenstein dies ... mathematician, who made contributions to the areas of differential equations, conformal mapping, and potential theory. He was also interested in theoretical physics, publishing research in hydrodynamics and astronomy.

File:Harry Daghlian.gif|link=Harry Daghlian (nonfiction)|1945: Physicist [[Harry Daghlian (nonfiction)|Harry Daghlian]] is fatally irradiated in a criticality accident during an experiment with the Demon core at Los Alamos National Laboratory.

||1957: Harald Sverdrup dies ... meteorologist and oceanographer known for his studies of the physics, chemistry, and biology of the oceans. He explained the equatorial countercurrents and helped develop the method of predicting surf and breakers. As scientific director of Roald Amundsen's polar expedition on Maud (1918-1925), Sverdrup worked extensively on meteorology, magnetics, atmospheric electricity, physical oceanography, and tidal dynamics on the Siberian shelf, and even on the anthropology of Chukchi natives. In 1953, Sverdrup quantified the concept of "critical depth", explaining the onset of the spring phytoplankton bloom in newly stratified water columns. Pic.

||1957: The Soviet Union successfully conducts a long-range test flight of the R-7 Semyorka, the first intercontinental ballistic missile.

File:Mars Observer diagram.png|link=Mars Observer (nonfiction)|1993: NASA loses contact with the [[Mars Observer (nonfiction)|Mars Observer]].

||1960: David Barnard Steinman dies ... engineer whose studies of airflow and wind velocity helped make possible the design of aerodynamically stable bridges. Steinman's thesis for his Ph.D. from Colombia University (1911) was published as "The Design of the Henry Hudson Memorial Bridge as a Steel Arch, and more than 20 years later he built the bridge he had planned over the Harlem River. Steinman designed more than 400 bridges. He also published children's books and poetry. Pic.

||1986: A limnic eruption at Lake Nyos in northwestern Cameroon kills 1,746 people and some 3,500 livestock.

||1989: The U.S. space probe Voyager 2 fired its thrusters to bring it closer to Neptune's mysterious moon Triton. This later photograph (left) shows a false-color image of Triton, taken two days before closest approach. At 2,700 km diameter, Triton is Neptune's largest satellite. The smallest features resolvable in this image are about 47 km across. The image is a composite of three images taken through ultraviolet, green, and violet filters.

||1993: Contact was lost with the Mars Observer spacecraft, following the pressurization of the rocket thruster fuel tanks, three days before it was to begin orbiting the Red Planet. The Mars Observer was to be the first U.S. spacecraft to study Mars since the Viking missions 18 years earlier. The fate of the $980 million mission remains unknown, though a commission studied possible causes for the failure.

||2011: Andreas Emil Petermann known as André Petermann dies - theoretical physicist known for introducing the renormalization group, suggesting a quark-like model, and work related to the anomalous magnetic dipole moment of the muon.

||2012: William Thurston dirs ... mathematician and academic ... a pioneer in the field of low-dimensional topology. In 1982, he was awarded the Fields Medal for his contributions to the study of 3-manifolds. Pic.

||2017: Great American Eclipse traverses the continental United States.

File:USS John S. McCain DDG-56.jpg|link=USS John S. McCain (DDG-56) (nonfiction)|2017: The destroyer [[USS John S. McCain (DDG-56) (nonfiction)|USS John S. McCain]] collides with the tanker ship ''Alnic MC'' off the coast of Singapore, leaving ten of her crew dead and another five injured.

File:Dennis_Paulson_of_Mars.jpg|link=Dennis Paulson of Mars|2017: ''[[Dennis Paulson of Mars]]'' broadcasts a minute of silence in recognition of the twenty-fourth anniversary of the loss of contact with [[Mars Observer (nonfiction)|Mars Observer]].

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