Danish astrologer and astronomer. (1546-1601) Born at Knudstrup, Scania (south Sweden, then part of Denmark); died at Prague (now in Czechoslovakia). Tycho was the greatest observational astronomer of his day. Given the island of Hven and enormous funds by King Frederick II, he built an observatory on the island and designed instruments which enabled him to observe the heavens with a degree of precision which revolutionized the science of astronomy. Kepler's access to Tycho's observations made possible the discovery of the basic laws of planetary motion. Among Tycho's accomplishments were the discovery of the nova of 1572, the comet of 1577, his detailed observation of planetary positions, and his catalog of exact positions of 777 stars. Tycho was an outrageous and colorful character who lost part of his nose in a duel (over some point in mathematics) and had it replaced with a piece of gold. He died by bursting his bladder by heavy drinking at a banquet. He computed horoscopes for patrons, and maintained a lifelong interest in astrology.