Galileo's Momentous Discoveries By careful observation through his telescopes, Galileo saw unprecedented detail. He discovered that: There are mountains and valleys on the Moon Venus cycles through a series of phases Jupiter is a sunlit planet with its own set of moons Spots form on and move across the surface of the Sun The Milky Way consists of countless numbers of stars Click on the links for detail about each discovery. Galileo started the process of the telescopic discovery of the Universe that continues unabated today.

a) There are mountains and valleys on the Moon b) Venus cycles through phases c) Jupiter has a set of moons d) Spots form and move on the Sun's surface e) The Milky Way consists of countless numbers of stars