Template:Selected anniversaries/April 29

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  1667: Physician, satirist, and polymath John Arbuthnot born. He will invent the figure of John Bull.

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  1854: Mathematician, physicist, and engineer Henri Poincaré born. He will make many original fundamental contributions to pure and applied mathematics, mathematical physics, and celestial mechanics.

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  1893: Chemist and astronomer Harold Urey born. Urey's pioneering work on isotopes will earn him the Nobel Prize in Chemistry in 1934 for the discovery of deuterium; he will also play a significant role in the development of the atom bomb, and contribute to theories on the development of organic life from non-living matter.

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  1986: Chernobyl disaster: American and European spy satellites capture the ruins of the 4th Reactor at the Chernobyl Power Plant.

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  2008: Chemist and academic Albert Hoffman dies. Hoffman is famous for discovering LSD, which he called his "problem child".