Galileo Galilei (1564–1642) was the Italian astronomer and physicist whose telescopic discoveries — the moons of Jupiter, the phases of Venus, the mountains of the Moon — proved that the Earth moves around the Sun, and whose 1633 trial by the Inquisition made him the enduring symbol of science against dogma.
A professor at Pisa and Padua, he improved the telescope to twentyfold magnification and, in 1610, published the 'Starry Messenger', announcing a universe no one had seen. His later work on motion laid the foundations of modern physics.
