Template:Selected anniversaries/September 19

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  1648: Blaise Pascal performs experiments to confirm the theory of atmospheric pressure and the existence of a vacuum.

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  1710: Astronomer and instrument maker Ole Rømer dies. He made the first quantitative measurements of the speed of light.

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  1749: Mathematician and astronomer Jean Baptiste Joseph Delambre born. He will be one of the first astronomers to derive astronomical equations from analytical formulas.

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  1761: Mathematician, astronomer, and philosopher Pieter van Musschenbroek dies. He invented the first capacitor in 1746: the Leyden jar.

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  1811: Mathematician and religious leader Orson Pratt born. As part of his system of Mormon theology, Pratt will embrace the philosophical doctrine of hylozoism.

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  1845: Famed gem detective and diplomat Niles Cartouchian foils villains, returns stolen relics, brokers peace accord.

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  1894: Mathematician Giuseppe Peano writes to Felix Klein, "The purpose of mathematical logic is to analyze the ideas and reasoning that especially figure in the mathematical sciences."

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  1921: Chemist and physicist James Dewar develops liquid gas condensor for use in fighting crimes against mathematical constants.

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  1922: "Fightin'" Bert Russell defeats Joseph Stalin in three-round bare-knuckle boxing match.

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  1935: Scientist and engineer Konstantin Tsiolkovsky dies. He was one of the founding fathers of modern rocketry and astronautics.

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  2017: Dennis Paulson of Mars credits scientist and engineer Konstantin Tsiolkovsky for "inspiring generations of astronauts."

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  2017: Steganographic analysis of Stardust reveals bootleg copy of Monkey's Jealous Ire by LEO Spacewagon.