370:(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.
296:, 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.
272:
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
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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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394:. 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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497:'s Optical Periscopic Imager for Comets (OPIC) instrument is named after Ernst Öpik to celebrate the first Estonia's contribution to a science mission of 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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809:"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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354:'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
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Optical
Periscopic Imager for Comets (OPIC) Tartu Observatory Space Exploration Group
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raised fear among
Estonians. Living as a refugee in Germany, he became the Estonian
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Collision probability with the planets and the distribution of planetary matter
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623:Öpik, Ernst (1922). "An estimate of the distance of the Andromeda Nebula".
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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"
453:". Annual Review of Astronomy and Astrophysics, vol. 15, p. 1
378: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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Foreign associates of the
National Academy of Sciences
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1958: "Physics of Meteor Flight in the Atmosphere".
436:", 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
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27:Estonian astronomer and astrophysicist (1893–1985)
568:"Fifty Years of the Irish Astronomical Journal"
299:In 1922 he correctly predicted the frequency of
768:Salpeter, Edwin E. "A Generalist Looks Back".
570:Fifty Years of the Irish Astronomical Journal
366:was discovered by the Russian civil engineer
8:
660:"Meteor Heights from the Arizona Expedition"
417:Gold Medal of the Royal Astronomical Society
149:Gold Medal of the Royal Astronomical Society
923:Members of the Estonian Academy of Sciences
771:Annual Review of Astronomy and Astrophysics
493:is sometimes called "Öpik-Oort cloud". The
787:Physics of meteor flight in the atmosphere
526:He was the father of the atomic physicist
466:Physics of Meteor Flight in the Atmosphere
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260:. He completed his 1923 doctorate at the
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948:Estonian emigrants to Northern Ireland
584:"The Densities of Visual Binary Stars"
838:Sonoma State University on Ernst Öpik
789:. New York: Interscience Publishers.
718:"Rocking Camera – Armagh Observatory"
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511:is named in his honour. The crater
294:rotational velocities of the galaxy
307:long before they were detected by
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908:Astronomers from Northern Ireland
322:. This cloud is now known as the
903:20th-century Estonian scientists
843:Armagh Observatory on Ernst Öpik
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938:Estonian World War II refugees
913:Moscow State University alumni
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958:Scientists from County Armagh
582:Öpik, Ernst (December 1916).
412:National Academy of Sciences
338:, describing the burning of
785:Öpik, Ernst Julius (1958).
358:Yarkovsky effect connection
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918:University of Tartu alumni
878:People from Kreis Wierland
873:People from Kunda, Estonia
953:People from Armagh (city)
831:26 September 2023 at the
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888:Estonian astrophysicists
883:20th-century astronomers
664:Proc Natl Acad Sci U S A
368:Ivan Osipovich Yarkovsky
523:is also named for him.
408:J. Lawrence Smith Medal
392:displaced persons camps
396:University of Maryland
238:Governorate of Estonia
200:(22 October [
76:governorate of Estonia
963:Irish astrophysicists
933:White movement people
685:10.1073/pnas.22.9.525
625:Astrophysical Journal
588:Astrophysical Journal
499:European Space Agency
898:Planetary scientists
893:Estonian astronomers
775:2002. 40:1–25. pg. 9
658:Öpik, Ernst (1936).
539:Member of Parliament
336:triple-alpha process
246:University of Moscow
128:University of Moscow
724:on 26 February 2013
676:1936PNAS...22..525O
637:1922ApJ....55..406O
600:1916ApJ....44..292O
549:from 1997 to 2010.
262:University of Tartu
240:then a part of the
133:University of Tartu
471:Dover Publications
214:Armagh Observatory
186:Armagh Observatory
495:Comet Interceptor
388:Baltic University
268:Astronomical work
244:. He went to the
228:Öpik was born in
198:Ernst Julius Öpik
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166:Scientific career
90:10 September 1985
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92:(1985-09-10)
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868:1985 deaths
863:1893 births
631:: 406–410.
594:: 292–302.
532:Lembit Öpik
421:Bruce Medal
406:He won the
275:white dwarf
155:Bruce Medal
113:Nationality
857:Categories
553:References
534:, was the
491:Oort cloud
479:0486438856
324:Oort cloud
206:astronomer
60:1893-10-22
48:Ernst Öpik
36:Ernst Öpik
754:26 August
728:26 August
528:Uuno Öpik
509:2099 Öpik
423:in 1976.
410:from the
348:red giant
344:carbon-12
283:Eridani B
250:asteroids
224:Education
176:Astronomy
829:Archived
704:16588103
506:asteroid
449:1977: "
442:1976: "
432:1951: "
380:Red Army
340:helium-4
116:Estonian
695:1076809
672:Bibcode
633:Bibcode
596:Bibcode
517:Martian
515:on the
386:of the
301:craters
258:meteors
157:in 1976
151:in 1975
795:837979
793:
702:
692:
521:Phobos
485:Legacy
477:
463:2004:
427:Papers
402:Awards
384:rector
256:, and
254:comets
172:Fields
142:Awards
98:Bangor
547:Wales
519:moon
458:Books
374:Exile
342:into
320:Pluto
277:star
230:Kunda
68:Kunda
791:OCLC
756:2012
730:2012
700:PMID
541:for
513:Öpik
504:The
489:The
475:ISBN
362:The
305:Mars
208:and
202:O.S.
87:Died
54:Born
690:PMC
680:doi
641:doi
604:doi
545:in
311:.
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