Tycho Brahe (1546-1601) constructed his own castle, Uraniborg, for astronomical observation, in Hven, Denmark.
Tycho Brahe with a huge quadrant. A quadrant is an instrument for measuring the height of a star (in angle). He greatly improved the accuracy of astronomical observations. [Figure from Victor E. Thoren, The Lord of Uraniborg: A biography of Tycho Brahe, Cambridge University Press, 1990]
Figure by S. Uchii
Last modified April 11, 2002. (c) Soshichi Uchii
