Bengt Strömgren
579576
219782654
2008-06-16T21:18:02Z
Lightbot
7178666
Units/dates/other
{{Unreferenced|date=June 2007}}
[[Image:Bengt Strömgren NYWTS.jpg|thumb|Bengt Strömgren, 1957]]
'''Bengt Georg Daniel Strömgren''' ([[January 21]] [[1908]] – [[July 4]] [[1987]]) was a [[Denmark|Danish]] [[astronomy|astronomer]] and [[astrophysics|astrophysicist]].
Bengt Strömgren was born in [[Gothenburg]]. His parents were Hedvig Strömgren (née Lidforss) and [[Elis Strömgren|Svante Elis Strömgren]], who was professor of [[astronomy]] at the [[University of Copenhagen]] and director of the University Observatory in Copenhagen. Bengt grew up in the professor's mansion surrounded with scientists, assistants, observers and guests. His father paced and promoted Bengt into a life with science, and Bengt's first paper was published already at the age of 14. He graduated from high school in 1925 and enrolled at the Copenhagen university. Only two years later, he graduated in astronomy and [[atomic physics]], and during the following two years, he completed a [[doctorate|doctoral degree]], which was evaluated with the best marks in December 1929, when he was 21 years old.
He gained a great deal of useful experience from his studies in [[theoretical physics]] at [[Niels Bohr]]'s Institute close by, and he was at the right place at the right time. He soon found out that he intended to use the fresh [[quantum physics]] in space, i.e. investigate the applications of [[quantum mechanics]] in stars. Obviously, questions of [[nepotism]] were in play when he applied for an assistantship already in 1925, which he didn't get. But only one year later it was given to him anyway — he was the best, regardless of his employer being also his own father.
After being appointed as lecturer at the university in 1932, Strömgren was invited to the [[University of Chicago]] in 1936 by [[Otto Struve]]. Going abroad for 18 months meant a lot to the young researcher, and when he went back to [[Denmark]] and to the rising [[national socialism]] in [[Europe]], he succeeded his father's professorship in 1940. During five years of isolation, under the [[Germany|German]] occupation of Denmark, he initiated the building of a new Danish Observatory, the [[Brorfelde Observatory]]. But after the [[Second World War]], Bengt Strömgren became tired of lacking state funding for the project, and with a stagnant national economy, he felt that he had to leave Danish research, which he did in 1951.
He went to the [[United States]] and became director of the [[Yerkes Observatory|Yerkes]] and [[McDonald Observatory|McDonald]] Observatories, and stayed there for six years. In 1957, he was appointed the first professor of theoretical astrophysics at the [[Institute for Advanced Study]] in Princeton, where he got [[Albert Einstein]]'s office. He stayed at Princeton with his family until 1967, when he went back to his homeland Denmark, and became the next to the last resident in a series of great Danish scientists of the [[Carlsberg Mansion]] og Honor, which had earlier been occupied by [[Niels Bohr]] among others. In 1987, he died after a short period of illness.
Bengt Strömgren made momentous contributions to astrophysics. He found that the [[chemical]] composition of [[stars]] was very much different than previously assumed. In the late 1930s, he found the relative abundance of [[hydrogen]] to be nearly 70 %, and [[helium]] to be about 27 %. Just before the war, he discovered the so-called [[Strömgren Spheres]] — huge interstellar shells of ionized hydrogen around stars. And in the 1950s and 1960s, he pioneered [[photoelectric photometry]] with a novel four-color system, now called [[Strömgren photometric system]].
==Honors==
'''Awards'''
*[[Bruce Medal]] (1959)
*[[Gold Medal of the Royal Astronomical Society]] (1962)
*[[Henry Norris Russell Lectureship]] (1965)
'''Named after him'''
*[[Asteroid]] [[1846 Bengt]]
*[[Strömgren age]]
*[[Strömgren photometry]]
*[[Strömgren sphere]]s
'''Miscellaneous'''
*Asteroid [[1493 Sigrid]], named after his wife
==External links==
*[http://phys-astro.sonoma.edu/BruceMedalists/Stromgren/ Bruce Medalist Bengt Strömgren]
*[http://www.ivh.au.dk/personale/simon_olling_rebsdorf/home.html Biographical PhD Project on Bengt Strömgren and Modern Astrophysics]
{{DEFAULTSORT:Stromgren, Bengt}}
[[Category:1908 births|Stromgren, Bengt]]
[[Category:1987 deaths|Stromgren, Bengt]]
[[Category:Danish astronomers|Stromgren, Bengt]]
[[Category:Astronomers]]
[[Category:University of Copenhagen alumni]]
[[Category:University of Copenhagen faculty]]
[[Category:University of Chicago faculty]]
[[Category:Institute for Advanced Study faculty]]
[[Category:Science teachers]]
[[da:Bengt Strömgren]]
[[de:Bengt Strömgren]]
[[el:Μπενγκτ Στρέμγκρεν]]
[[fr:Bengt Strömgren]]
[[it:Bengt Georg Daniel Strömgren]]
[[ja:ベンクト・ストレームグレン]]
[[no:Bengt Strömgren]]
[[sv:Bengt Strömgren]]
[[zh:本特·斯特龙根]]