359:(1844–1902), who worked on scientific problems in his spare time. Writing in a pamphlet around the year 1900, Yarkovsky noted that the diurnal heating of a rotating object in space would cause it to experience a force that, while tiny, could lead to large long-term effects in the orbits of small bodies, especially meteoroids and small asteroids. Yarkovsky's work might have been forgotten had it not been for Öpik, who read Yarkovsky's pamphlet sometime around 1909. Decades later, Öpik discussed the possible importance of the Yarkovsky effect for moving meteoroids about the solar system.
285:, which depends on the total mass around which stars are rotating, and on the assumption that the luminosity per unit mass was the same as that of our galaxy. He concluded that the distance was 450 kpc. His result was in good accordance with other estimates of these days (100 to 1000 kpc) and were closer to recent estimates (778 kpc) than Hubble's result (275 kpc). His method is still widely used.
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He was the first and longest serving editor of the Irish
Astronomical Journal (1950 to 1980) and frequently published his own research there. In 1916 he published an article there in which he estimated the densities of visual binary stars. Using the
387:, which he visited annually, typically for one semester. As air travel became more common, his refusal to fly made travel to the U.S. from Armagh systematically more difficult and he eventually ceased the annual ritual.
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in 1960, the
Meteoritical Society Frederick C. Leonard Memorial Medal in 1968, the Kepler Gold Medal from the American Association for the Advancement of Science & Meteoritical Society in 1972, the
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383:. In 1948 he was offered a post in Armagh and remained there despite offers of lucrative jobs in America. From the early 1960s to the mid-1970s he also held a position at the
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and Samuel L. Boothroyd headed the
Arizona meteor expedition, which detected approximately 22,000 meteors. He also invented a
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798:"Estonian technology to be part of the European Space Agency's mission for the first time, University of Tartu, 26.06.2019"
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343:'s paper on the same subject had already been published by the time Öpik's paper reached Britain and the United States.
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or alternatively the Öpik-Oort Cloud in his honour. From
October 1931 to the end of July 1933, Öpik,
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435:", Elsevier Scientific Publishing Co., "Developments in Solar System and Space Science", vol 2
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561:, by A.G. Gunn & J. McFarland, Irish Astronomical Journal, vol. 27, iss. 1, p. 7 (2000)
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Optical
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raised fear among
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Collision probability with the planets and the distribution of planetary matter
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In 1932 he postulated a theory concerning the origins of comets in the
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In 1922 he published a paper in which he estimated the distance to the
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for the study of meteors. In 1951 he published a paper concerning the
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Interplanetary encounters: Close-range gravitational interactions
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About dogma in science and other recollections of an astronomer
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10 October] 1893 – 10 September 1985) was an
Estonian
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Recipients of the Gold Medal of the Royal
Astronomical Society
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Evening
Standard (London); "Lembit and his Very Cheeky Family"
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442:". Annual Review of Astronomy and Astrophysics, vol. 15, p. 1
367:Öpik fled his native country in 1944 because the approaching
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stars. However, this achievement is often overlooked because
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who spent the second half of his career (1948–1981) at the
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National Academy of Sciences
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1958: "Physics of Meteor Flight in the Atmosphere".
425:", Proc. R. Irish Acad. Sect. A, vol. 54, p. 165-199
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to specialize in the study of minor bodies, such as
733:"Rocking-mirror Meteor Camera – Armagh Observatory"
16:Estonian astronomer and astrophysicist (1893–1985)
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557:"Fifty Years of the Irish Astronomical Journal"
288:In 1922 he correctly predicted the frequency of
757:Salpeter, Edwin E. "A Generalist Looks Back".
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559:Fifty Years of the Irish Astronomical Journal
355:was discovered by the Russian civil engineer
649:"Meteor Heights from the Arizona Expedition"
406:Gold Medal of the Royal Astronomical Society
138:Gold Medal of the Royal Astronomical Society
912:Members of the Estonian Academy of Sciences
760:Annual Review of Astronomy and Astrophysics
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482:is sometimes called "Öpik-Oort cloud". The
776:Physics of meteor flight in the atmosphere
515:He was the father of the atomic physicist
455:Physics of Meteor Flight in the Atmosphere
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249:. He completed his 1923 doctorate at the
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937:Estonian emigrants to Northern Ireland
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573:"The Densities of Visual Binary Stars"
827:Sonoma State University on Ernst Öpik
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778:. New York: Interscience Publishers.
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707:"Rocking Camera – Armagh Observatory"
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500:is named in his honour. The crater
283:rotational velocities of the galaxy
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296:long before they were detected by
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897:Astronomers from Northern Ireland
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311:. This cloud is now known as the
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832:Armagh Observatory on Ernst Öpik
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927:Estonian World War II refugees
902:Moscow State University alumni
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947:Scientists from County Armagh
571:Öpik, Ernst (December 1916).
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401:National Academy of Sciences
327:, describing the burning of
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774:Öpik, Ernst Julius (1958).
347:Yarkovsky effect connection
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907:University of Tartu alumni
867:People from Kreis Wierland
862:People from Kunda, Estonia
942:People from Armagh (city)
820:26 September 2023 at the
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653:Proc Natl Acad Sci U S A
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357:Ivan Osipovich Yarkovsky
512:is also named for him.
397:J. Lawrence Smith Medal
381:displaced persons camps
385:University of Maryland
227:Governorate of Estonia
189:(22 October [
65:governorate of Estonia
952:Irish astrophysicists
922:White movement people
674:10.1073/pnas.22.9.525
614:Astrophysical Journal
577:Astrophysical Journal
488:European Space Agency
887:Planetary scientists
882:Estonian astronomers
764:2002. 40:1–25. pg. 9
647:Öpik, Ernst (1936).
528:Member of Parliament
325:triple-alpha process
235:University of Moscow
117:University of Moscow
713:on 26 February 2013
665:1936PNAS...22..525O
626:1922ApJ....55..406O
589:1916ApJ....44..292O
538:from 1997 to 2010.
251:University of Tartu
229:then a part of the
122:University of Tartu
460:Dover Publications
203:Armagh Observatory
175:Armagh Observatory
484:Comet Interceptor
377:Baltic University
257:Astronomical work
233:. He went to the
217:Öpik was born in
187:Ernst Julius Öpik
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79:10 September 1985
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519:. His grandson,
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81:(1985-09-10)
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857:1985 deaths
852:1893 births
620:: 406–410.
583:: 292–302.
521:Lembit Öpik
410:Bruce Medal
395:He won the
264:white dwarf
144:Bruce Medal
102:Nationality
846:Categories
542:References
523:, was the
480:Oort cloud
468:0486438856
313:Oort cloud
195:astronomer
49:1893-10-22
37:Ernst Öpik
25:Ernst Öpik
743:26 August
717:26 August
517:Uuno Öpik
498:2099 Öpik
412:in 1976.
399:from the
337:red giant
333:carbon-12
272:Eridani B
239:asteroids
213:Education
165:Astronomy
818:Archived
693:16588103
495:asteroid
438:1977: "
431:1976: "
421:1951: "
369:Red Army
329:helium-4
105:Estonian
684:1076809
661:Bibcode
622:Bibcode
585:Bibcode
506:Martian
504:on the
375:of the
290:craters
247:meteors
146:in 1976
140:in 1975
784:837979
782:
691:
681:
510:Phobos
474:Legacy
466:
452:2004:
416:Papers
391:Awards
373:rector
245:, and
243:comets
161:Fields
131:Awards
87:Bangor
536:Wales
508:moon
447:Books
363:Exile
331:into
309:Pluto
266:star
219:Kunda
57:Kunda
780:OCLC
745:2012
719:2012
689:PMID
530:for
502:Öpik
493:The
478:The
464:ISBN
351:The
294:Mars
197:and
191:O.S.
76:Died
43:Born
679:PMC
669:doi
630:doi
593:doi
534:in
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292:on
205:in
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Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
