Italian scientist and natural philosopher (1564-1642) best remembered for his work in astronomy, where he observed the Milky Way, some of Jupiter's moons and the mountains on the Moon. His agreement with Copernicus that the Earth orbited the sun brought him trouble with the Inquisition in 1611; he promised to abjure unorthodox views, but a new publication in 1632 caused him to be arrested and imprisoned for heresy. The Duke of Tuscany was able to have the sentence commuted to house arrest.