Final answer:
Galileo Galilei supported the heliocentric model, which positions Earth revolving around the sun, and provided evidence for the Copernican theory.
Step-by-step explanation:
Galileo Galilei supported the idea that Earth revolves around the sun, which is known as the heliocentric model of the cosmos. This conflicted with the long-held belief that Earth was the center of the universe. Galileo's support for this view was built on his telescopic observations and experiments in physics, which provided evidence for the Copernican theory introduced by Nicolaus Copernicus. Galileo is celebrated for his groundbreaking work that contributed to the scientific revolution and ultimately changed the way we understand our place in the universe.