Just prior to his death in May 1524, Nicolaus Copernicus published De Revolutionibus Orbium Coelestium (On the Revolutions of the Celestial Spheres), a groundbreaking treatise that laid out mathematical proofs that formulated a heliocentric, non-Ptolemaic cosmology. While not the first to do so, Copernicus had more technology available to him than the Greek and Islamic astrologers that came before him, and was able to prove that the earth did not occupy the center of our solar system with more conclusive evidence.
Given that the earth revolves around the sun, objects periodically pass between the earth and the sun.