Jan Oort

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Jan Oort
Born April 28, 1900
Franeker, Friesland
Died November 5, 1992
Leiden
Nationality Dutch
Fields astronomy
Doctoral advisor Jacobus Cornelius Kapteyn
Known for Oort cloud

Jan Hendrik Oort (April 28, 1900 – November 5, 1992) was a Dutch astronomer. He stimulated radio astronomy. The Oort cloud of comets bears his name.

Oort was born in Franeker, Friesland and studied in Groningen with Jacobus Cornelius Kapteyn. His Ph.D thesis was titled The stars of high velocity. In 1927 he confirmed Bertil Lindblad's theory that the Milky Way galaxy rotates, by analyzing the movements of stars.[1] In 1935 he became professor at the observatory of the University of Leiden, where Ejnar Hertzsprung was the director.

Oort was fascinated by radio waves from the universe. After the Second World War he was a pioneer in the new field of radio astronomy, using an old radar antenna from the Germans.

In the 1950s he raised funds for a new radio telescope in Dwingeloo, in the east part of the Netherlands, to research the center of the galaxy. In 1970 a bigger telescope (the Westerbork Synthesis Radio Telescope) was built in Westerbork, near the old one. It consisted of twelve smaller telescopes working together to perform radio interferometry observations, a technique which had been previously suggested by Oort, but which was first tested experimentally in Cambridge by Martin Ryle and in Sydney by Joseph Pawsey.

His hypothesis that the comets have a common origin, postulated in 1950, was later proven to be correct. Another contribution of Oort was that he was able to demonstrate that the light from the Crab nebula was polarized.

Oort died on November 5, 1992 in Leiden.

Contents

[edit] A few of Oort's discoveries

[edit] Honors

Awards

Named after him

Upon his death, Subrahmanyan Chandrasekhar remarked "The great oak of Astronomy has been felled, and we are lost without its shadow", reflecting the high regard in which Oort was held by his colleagues.

[edit] References

  1. ^ a b J. H. Oort (1927 April 14). "Observational evidence confirming Lindblad's hypothesis of a rotation of the galactic system". Bulletin of the Astronomical Institutes of the Netherlands 3 (120): 275–282. 
  2. ^ J. H. Oort (June 1924). "On a Possible Relation between Globular Clusters and Stars of High Velocity". Proc Natl Acad Sci U S A. 10 (6): 256–260. doi:10.1073/pnas.10.6.256. PMID 1085635. 

[edit] Online exhibition

Jan Oort, astronomer (Leiden University Library, April-May 2000) [1]