What did Aristotle and Galileo Galilei contribute to planetary/earth studies? ?
Aristotle summarized the geocentric view of the universe in his works. However, he did not himself make any major contribution to the field. Galileo argued extensively for the heliocentric picture of the solar system that we all learn about in grade school today. He used many lines of argument, some of which were based on his telescopic observations of the moons of Jupiter, the phases of Venus, the sunspots (and the rotation of the sun on its axis) and the topography of the moon, among other things. Curiously, the one argument that he thought was the clincher – his explanation of the tides – turned out to be wrong.