Nicolaus Copernicus (1473-1543) was a Polish astronomer who is considered the founder of modern astronomy. He was the first to propose that the Earth and other planets revolve around the sun (heliocentrism), rather than the Earth being the center of the universe. Copernicus received a good education after his father died, studying mathematics and law and visiting several universities in Italy. His greatest accomplishment was publishing his theory of heliocentrism in 1543, shortly before his death.