Willem Hendrik van den Bos
Willem Hendrik van den Bos (born September 25, 1896 in Rotterdam , † March 30, 1974 in Johannesburg ) was a Dutch-South African astronomer . He was mainly concerned with the discovery, measurement and cataloging of visual binary stars .
Van den Bos studied from 1913 (with an interruption due to military service) in Leiden . He carried out series of measurements on binary stars with the 10½- inch from the university observatory (1920–1925) and received his doctorate in 1925 with a thesis on "Micrometer measurements on binary stars" .
In the same year he went to the Union Observatory near Johannesburg as a volunteer . This happened at the invitation of its director, the double star expert RTA Innes , who was looking for an experienced observer to support the work on the new 26½-inch model.
The stay originally planned for three years turned into 41 years. At the end of the three years, Van den Bos initially took up a position as main assistant at HE Wood , Innes' successor. From 1941 to 1956 he was director of the observatory himself. Even after he retired, van den Bos remained active until he had to quit his astronomical activity in 1966 for health reasons.
The clear air of South Africa favored extensive observation series. The tireless observer van den Bos discovered a total of around 3,000 new pairs of stars and carried out 74,000 measurements. For almost all observations he used the observatory's 26½-inch, interrupted only by research stays at the Yerkes and McDonald observatories (1957–58) and the Lick observatory (1961–63).
Van den Bos compiled a complete list of all 18,000 known double stars between −19 ° declination and the southern celestial pole, as well as the more than 95,000 measurements taken on these stars. This catalog was his contribution to the "Index Catalog of Visual Double Stars, 1961.0" , which was published in 1963 in collaboration with the Lick Observatory.
Van den Bos also devoted himself to theoretical work: He further developed Thiele-Innes' method for determining the orbit of double stars, published more than 150 sets of orbital elements (still without the support of mechanical calculators) and also worked on various other calculation methods.
From 1938 to 1952 van den Bos was President of Commission 26 (Double Stars) of the International Astronomical Union . In 1943/44 and 1955/56 he was President of the Astronomical Society of Southern Africa.
Van den Bos received the Gold Medal from the Royal Danish Academy of Sciences and the Gill Medal from the Astronomical Society of Southern Africa. The asteroid (1663) van den Bos and a moon crater were named after him.
Web links
- Publications by WH van den Bos in the Astrophysics Data System
- Obituaries for HW van den Bos in the Astrophysics Data System
- J. McFarland: Van den Bos, Willem Hendrik. in: Th. Hockey (Ed.): Biographical Encyclopedia of Astronomers. Springer 2007, ISBN 978-0-387-31022-0 ( Google Books )
- Biography on the websites of the Astronomical Society of Southern Africa
- Portrait in the Photographic Archives of the University of Chicago
Individual evidence
- ↑ Past ASSA Presidents on the websites of the Astronomical Society of Southern Africa ( Memento of the original from December 23, 2015 in the Internet Archive ) Info: The archive link has been inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
- ^ Fourth Gill Medal. Monthly Notes of the Astron. Soc. Southern Africa, Vol. 19 (1960), p. 77 ( online )
| personal data | |
|---|---|
| SURNAME | Bos, Willem Hendrik van den |
| BRIEF DESCRIPTION | Dutch-South African astronomer |
| DATE OF BIRTH | September 25, 1896 |
| PLACE OF BIRTH | Rotterdam |
| DATE OF DEATH | March 30, 1974 |
| Place of death | Johannesburg |