Explain how galileo's discovery of a rotating sun supported the copernican view of a sun-centered universe?

Question

Explain how galileo's discovery of a rotating sun supported the copernican view of a sun-centered universe?

Answer 1

The prevailing view was that the sun was perfect, being made of quintessence and thus featureless. Galileo was the first to see sunspots, which were "imperfections" on this supposedly "perfect" body. What's more, they rotated is such a way to show that the sun rotated on its axis, and at the same time they changed shape, appeared and disappeared.

This was one more evidence that the universe was not made of a perfect, immutable material from the "sphere of the moon" upward.

Other pieces of evidence discovered by Galileo were the mountains on the moon (Galileo actually measured their heights, using the shadows they cast), the phases of Venus, and the moons of Jupiter, which looked like a miniature Copernican solar system.

Draw a diagram of the phases of Venus as they would be seen from earth in a Copernican system and a Ptolemaic system, and you will see a dramatic and contradictory difference.

Answer 2

Galileo actually used his telescope to discover that the moons of Jupier orbited Jupiter.  At the time the standard dogma was that all objects were centered around the earth.  This added weight to the theory that the earth orbited the sun, since the earth clearly wasn't the center of the universe based on Galileo's discoveries.