228:, Johannesburg, to provide access to the southern skies invisible from Europe. During this time he was responsible for photographic observations of variable stars to record their changes in brightness, and of selected regions of the sky to measure colours of stars. The photographic plates were sent to the Netherlands for measurement and analysis.
256:. The observatory was equipped with a 1.9-metre (74-inch) aperture reflecting telescope, then the largest telescope in the southern hemisphere. A new spectrograph was commissioned in 1951 and Wesselink set to work studying the radial velocities of hot, luminous stars in the Milky Way to improve knowledge about the rotation of the disk of the
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He remained at Leiden
University during the Nazi occupation in the Second World War, maintaining the functioning of the institution following the resignation of many senior staff members. He married Jeanette van Gogh in 1943.
150:(1909β1995) was a Dutch astronomer who worked successively in the Netherlands, South Africa and the United States. He specialised in observing and understanding the characteristics of stars, particularly
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In 1946 Wesselink was sent to the Leiden
Observatory's outpost in South Africa to act as its superintendent. The Leiden station was located in the grounds of the
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170:. His father was a medical doctor and his mother was a nurse. Inspired by his parents, Adriaan Wesselink developed an interest in science.
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where he was appointed to an assistantship. He pursued research into variable stars. He was trained by prominent astronomers including
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variable stars in the
Magellanic Clouds, which provided much improved measurements of the distances to these two nearby galaxies.
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Wesselink worked on many projects relating to stars. These included calculations of the surface brightnesses and radii of stars.
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Wesselink, A. J. (1946). "The observations of brightness, colour and radial velocity of Ξ΄ Cephei and the pulsation hypothesis".
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using measurements of its brightness, its colour and the radial velocity of its surface, assuming the star behaved as a
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Milone, Eugene F. (2014). "Wesselink, Adriaan Jan". In Hockey, Thomas; Trimble, Virginia; Williams, Thomas R. (eds.).
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outside of the total phase in an attempt to measure how the surface brightness of the Sun varies across its disk.
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SZ Camelopardalis that used measurements of its brightness from 12000 photographic plates.
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In 1950 Adriaan
Wesselink was appointed chief assistant of the Radcliffe Observatory in
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In 1964 Wesselink was appointed a research associate in the astronomy department of
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201:. He made photographic observations of the brightness of the Sun during the
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Photographic
Photometry Applied to the Variable Star SZ Camelopardalis
300:. Wesselink became closely involved in the work from the observatory.
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During this period he calculated the mean radius of the variable star
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284:, and in 1965 became a senior research astronomer there. Yale and
260:. He also carried out photoelectric photometry of stars in the
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Monthly Notes of the
Astronomical Society of Southern Africa
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in 1926 and the technique subsequently became known as the
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Wesselink was awarded a PhD in 1938 for research into the
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in emitting light. This developed a method suggested by
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Wesselink studied physics, mathematics and astronomy at
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Quarterly
Journal of the Royal Astronomical Society
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311:Adriaan Wesselink retired in 1977. He died in
162:Adriaan Wesselink was born on 7 April 1909 in
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359:Bulletin of the American Astronomical Society
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443:(1995). "Adriaan Jan Wesselink, 1909β1995".
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356:(1995). "Adriaan Jan Wesselink, 1909β1995".
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290:southern-hemisphere station at El Leoncito
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555:Fellows of the Royal Astronomical Society
473:Biographical Encyclopedia of Astronomers
181:Astronomical research in the Netherlands
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585:Dutch emigrants to the United States
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590:Dutch expatriates in South Africa
288:universities had established a
575:20th-century Dutch astronomers
486:10.1007/978-1-4419-9917-7_1458
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405:(1996). "Adriaan Wesselink".
276:Research in the United States
203:total eclipse of 19 June 1936
16:Dutch astronomer (1909β1995)
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580:People from Hellevoetsluis
560:Utrecht University alumni
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565:Leiden University alumni
264:. In collaboration with
570:Yale University faculty
210:eclipsing variable star
185:Wesselink proceeded to
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319:, on 12 January 1995.
246:Baade-Wesselink method
148:Adriaan Jan Wesselink
28:Adriaan Jan Wesselink
220:Work in South Africa
525:1946BAN....10...91W
478:Springer Publishing
457:1995MNSSA..54...84F
421:1996QJRAS..37...95.
372:1995BAAS...27.1486E
175:Utrecht University
99:Utrecht University
495:978-1-4419-9917-7
262:Magellanic Clouds
226:Union Observatory
191:Ejnar Hertzsprung
187:Leiden University
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110:Scientific career
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476:. New York:
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415:(1): 95β97.
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64:(1995-01-12)
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550:1995 deaths
545:1909 births
317:Connecticut
307:Later years
199:Jan Woltjer
168:Netherlands
85:Nationality
74:Connecticut
52:Netherlands
539:Categories
323:References
237:black body
158:Early life
40:1909-04-07
451:: 84β85.
313:New Haven
298:Argentina
120:Astronomy
70:New Haven
294:San Juan
286:Columbia
270:RR Lyrae
254:Pretoria
521:Bibcode
453:Bibcode
417:Bibcode
368:Bibcode
166:in the
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258:Galaxy
136:(1938)
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127:Thesis
116:Fields
292:near
89:Dutch
490:ISBN
197:and
59:Died
34:Born
482:doi
296:in
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