Besides celestial bodies orbiting Jupiter, what other observation about the Sun itself indicated the heavens were dynamic?

Answer

Galileo observed sunspots moving across its surface.

Galileo observed sunspots, which were temporary blemishes that moved across the Sun's surface, further cementing the idea that the heavens were dynamic and subject to change, just like the Earth.

Besides celestial bodies orbiting Jupiter, what other observation about the Sun itself indicated the heavens were dynamic?
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