Tycho Brahe

Born into Danish nobility on 14 December 1546, Tycho Ottesen Brahe received a thorough education befitting his station. In 1572 he spotted a completely new star brighter than any known body - impossible under Aristotelian doctrine - and spent the next fifteen years obsessed with building ever more accurate instruments. King Frederick II gave him the island of Hven and funding for Uraniborg, Christian Europe's first large observatory, later supplemented by the underground Stjerneborg when he found his original equipment insufficiently stable. He proved that "new stars" lay beyond the Moon and that comets weren't atmospheric, refuting centuries of belief in his 1573 De nova stella. He devised his own model of the universe - the Tychonic system, with Earth at center, the Sun circling it, and planets circling the Sun - trying to fuse Copernican geometry with Ptolemaic philosophy. Forced out by the new king Christian IV in 1597, he moved to Prague as imperial astronomer and built another observatory at Benátky nad Jizerou. In his final year, 1600-1601, a young Johannes Kepler assisted him; Kepler would use Tycho's measurements to unlock the laws of planetary motion a