Galileo’s Amazing Discoveries What did he see? What explanations did he create? How were these theories tested? How did he share the information? Galileo

Galileo’s Observations Moon’s Surface Galileo

The Moon’s Rough Surface Craters & Mountains Counter to Aristotelean idea (& Catholic Church) that "heavens" were perfect… Galileo

Sunspots More proof heavens weren't perfect. Systematic observations of the motion of the sunspots that indicated the Sun was rotating on its axis. Galileo

Moons Orbiting Jupiter Galileo

Moons Orbiting Jupiter Jupiter's moons clearly did NOT orbit the Earth, as the geocentric model required Jupiter could hold onto its moons while it clearly moved across the sky, so the Earth could also do the same with its Moon. Galileo

Stars in the Milky Way millions of stars in the Milky Way Fuzzy white Milky Way had millions and millions of stars Galileo

Saturn’s Bulge Non-uniform shape of Saturn = the heavens weren't perfect. Saturn was NOT round, and the "bulges" of the rings were proof that the planets weren’t simple spheres moving in the sky. Galileo

Venus’ Phases Changing sizes & phases of Venus. Seeing BOTH prove it had to be orbiting the Sun, and not Earth. If Venus orbited the Sun, then it didn't orbit Earth, and the Geocentric model was wrong. Galileo

Venus’ Phases Galileo

The Process of Science Observation Description of Experiments Encouragement for others to repeat Sharing Hypotheses Publishing for Others to Read Revising explanations Galileo