Jan Oort | |
---|---|
Born | 28 April 1900 Franeker, Friesland |
Died | 5 November 1992 (aged 92) Leiden, South Holland |
Nationality | Dutch |
Fields | Astronomy |
Doctoral advisor | Jacobus Cornelius Kapteyn |
Known for | Oort cloud |
Notable awards |
Vetlesen Prize (1966) Kyoto Prize (1987) |
Jan Hendrik Oort ForMemRS[1] (28 April 1900 – 5 November 1992) was a Dutch astronomer who made significant contributions to the understanding of the Milky Way and a pioneer in the field of radio astronomy.[2] His New York Times obituary called him "one of the century's foremost explorers of the universe;"[3] the European Space Agency website describes him as, "one of the greatest astronomers of the 20th century," and states that he "revolutionised astronomy through his ground-breaking discoveries."[4] In 1955, Oort’s name appeared in Life Magazine’s list of the 100 most famous living people.[5] He has been described as "putting the Netherlands in the forefront of postwar astronomy."[3]
Oort determined that the Milky Way rotates and overturned the idea that the sun is at its center; he discovered mysterious invisible 'dark matter' in 1932 which is believed to make up more than 90% of the Universe and whose gravitational pull causes "the clustering of stars into galaxies and galaxies into connecting strings of galaxies."[3][6] He discovered the galactic halo, a group of stars orbiting the Milky Way but outside the main disk.[7] Additionally Oort is responsible for a number of important insights about comets, including the realization that their orbits "implied there was a lot more solar system than the region occupied by the planets."[3]
The Oort cloud, the Oort constants, and the Asteroid, 1691 Oort, were all named after him.