Tycho Brahe

Tycho Brahe (1546–1601), born at Knutstorp in Danish Scania, was the greatest astronomer of the pre-telescopic age. His 1572 observations of a new star in De nova stella (1573) shattered the Aristotelian idea of an unchanging sky.

King Frederick II gave him the island of Hven, where from 1576 he built Uraniborg and gathered precise planetary data. He later worked at the underground observatory Stjerneborg.

Forced out by Christian IV in 1597, he became imperial astronomer in Prague under Rudolf II, where Johannes Kepler assisted him until his death in 1601. Kepler later used his data to develop the laws of planetary motion.