About Ernst Öpik
Ernst Julius Öpik was an Estonian astronomer and astrophysicist who spent the second half of his career (1948–1981) at the Armagh Observatory in Northern Ireland. He is best known for his pioneering work on solar system dynamics, particularly of the Oort cloud and the Yarkovsky effect. He was the first and longest serving editor of the Irish Astronomical Journal (1950–1980) and frequently published his own research there. He also invented a rocking camera for the study of meteors. The Yarkovsky effect was discovered by the Russian civil engineer Ivan Osipovich Yarkovsky (1844–1902), who worked on scientific problems in his spare time.
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