Template:On This Day (nonfiction)/May 10

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  28 BC: A sunspot is observed by Han dynasty astronomers during the reign of Emperor Cheng of Han, one of the earliest dated sunspot observations in China.

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  1482: Mathematician and astronomer Paolo dal Pozzo Toscanelli dies. Thanks to his long life, his intelligence and his wide interests, Toscanelli was one of the central figures in the intellectual and cultural history of Renaissance Florence in its early years.

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  1829: Polymath and physician Thomas Young dies. Young made notable scientific contributions to the fields of vision, light, solid mechanics, energy, physiology, language, musical harmony, and Egyptology.

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  1900: Astronomer and astrophysicist Cecilia Payne-Gaposchkin born. Her doctoral thesis will establish that hydrogen is the overwhelming constituent of stars, and accordingly the most abundant element in the universe.

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  1906: New York mobster and hit man Abe Reles born. A notorious killer, he will fall to his death in 1941 while under police custody, ostensibly a failed escape attempt but widely believed to be murder.

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  1960: The nuclear submarine USS Triton completes Operation Sandblast, the first underwater circumnavigation of the earth.