The One Significant Observation Galileo Made Through His Home-Built Telescope

Multiple Choice

The one significant observation Galileo made through his home-built telescope that convinced him that the planets revolved around the Sun was the

A) appearance of the Milky Way as a mass of individual stars.
B) discovery of rings around the planet Saturn.
C) appearance of mountains and craters on the Moon.
D) appearance of Venus following a cycle of phases, from crescent through quarter and gibbous phases to full.