Jacobus Cornelius Kapteyn, (January 19, 1851-June 18, 1922) was a Dutch astronomer, best known for his extensive studies of the Milky Way and as the first discoverer of evidence for galactic rotation. Kapteyn was born in Barneveld, and went to the University of Utrecht to study mathematics and physics in 1868. In 1875, after having finished his thesis, he worked for three years at the Leiden Observatory, … Wikipedia
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