What crucial element did Galileo’s discovery provide that Copernicus’s earlier proposal lacked?

Answer

The first direct, irrefutable proof that Earth was not the universal anchor

While Copernicus relied on mathematical elegance, Galileo provided the first major empirical nail in the coffin for the dominant cosmological view by offering direct visual confirmation that Earth was not the anchor of motion.

What crucial element did Galileo’s discovery provide that Copernicus’s earlier proposal lacked?
Galileoastronomyobservationsheliocentric modelJupiter's moons