How was it proven that the earth rotates around the sun?
Slow and steady missing of some stars and arrival of new stars at the western and eastern fringes of the night sky, marking transits, from one zodiac to another, every month, were proofs...
All were unanimous in associating Earth with the Moon in proximity and, likewise, with close by Sun..
Ancient astronomers (sky gazers) divided the star world they could see
They watched some continuous clockwise movement and repeat appearance of every zodiac-configuration,. exactly after a period called a year. These formed the basis, for later developments and findings.
Copernicus confirmed that Sun is the center of the universe and Kepler continued with correlations to prove that planets revolved around Sun in elliptic orbits, with Sun at a common focus. .