Kapteyn and Statistical Astronomy

Abstract

If Jacobus Cornelius Kapteyn (1851–1922) were here today, he would undoubtedly be among those asking the new questions on the cutting edge of contemporary astronomy. It is likely that he would even find a survey of his own contributions to the study of the Milky Way irrelevant. Nevertheless, Kapteyn’s life-long interest in the Milky Way shaped the work of many astronomers, including, of course, his students, Willem de Sitter, H.A. Weersman, Pieter van Rhijn, and through van Rhijn: Jan Oort, Bart Bok and many others. But Kapteyn’s influence extended far beyond his native Holland. After Kapteyn became a close colleague of George Ellery Hale and a Research Associate at the Mount Wilson facilities in 1908, Hale began to employ a number of Dutch astronomers, including van Rhijn, Adriaan van Maanen, and Kapteyn’s Danish future son-in-law, Ejnar Hertzsprung. Moreover, Kapteyn’s astronomical colleagues world-wide found his enthusiasm and penetrating insights infectious.