Jacobus cornelius kapteyn biography of williams

(b. Barneveld, Netherlands, 19 January 1851; d. Amsterdam, Netherlands, 18 June 1922)

astronomy.

Kapteyn was the ninth of fifteen children of G. J. Kapteyn and E. C. Koomans, who conducted a boarding school for boys in Barneveld. Many of these children were extraodinarily gifted in science. As a boy Kapteyn showed outstanding intellectual ability and curiosity. At the age of sixteen he passed the entrance examination for the University of Utrecht, which, however, his parents judged him too young to enter until the following year. He studied mathematics and physics and obtained the doctor’s degree with a thesis on the vibration of a membrane. Kapteyn was interested in many branches of science, and it was mostly through his accepting (1875) a position as observator at the Leiden observatory that he began his career in astronomy. In 1878, at the age of twerntyseven, he was elected to the newly instituted chair of astronomy and thoerectical mechanics at the University of Groningen, which he held until his retirement in 1921 at the age of seventy.

Kapteyn’s major contributions are in the field of stellar astronomy, particularly in research on the space distribution and motions of the stars. At the time of these studies, the problem of the space

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Text Biography

Kapteyn, Jacobus Cornelius (1851–1922)

Dutch astronomer who analysed the structure of the universe by studying the distribution of stars using photographic techniques. To achieve more accurate star counts in selected sample areas of the sky he introduced the technique of statistical astronomy. He also encouraged fruitful international collaboration among astronomers.

Kapteyn was born in Barneveld, the Netherlands, on 19 January 1851. He was born into a large and talented family and displayed great academic abilities early in his life. He began his studies at the University of Utrecht in 1868 when he was 17, although he had already satisfied the university's entrance requirements a year earlier. Kapteyn concentrated his studies on mathematics and physics and earned his doctorate for a thesis on vibration.

Kapteyn's career in astronomy began when he was employed by the astronomical observatory at Leiden in 1875. Three years later he was appointed as the first professor of astronomy and theoretical mechanics at the University of Groningen. He was a member of the French Academy of Science and a fellow of the Royal Society. He was active in the organizational work that eventually led to the establishment of the International Union of Astronomers. He retired