What fundamental concept about celestial motion did Galileo disprove by observing objects orbiting Jupiter?

Answer

That the Earth was the sole center of motion in the cosmos

Since Jupiter clearly had satellites orbiting it, this demonstrated that other centers of motion existed, directly contradicting the requirement of the geocentric Ptolemaic model that everything must orbit the Earth.

What fundamental concept about celestial motion did Galileo disprove by observing objects orbiting Jupiter?
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