What astronomical discovery provided Galileo with a small, working model contradicting the idea that everything orbits Earth?

Answer

Four celestial bodies orbiting Jupiter

The discovery of Jupiter's satellites demonstrated a system where motion clearly did not center on the Earth, providing an exception to the established cosmological rule.

What astronomical discovery provided Galileo with a small, working model contradicting the idea that everything orbits Earth?
GalileosunEarthrotationProof