Nicolaus Copernicus (19 February 1473 – 24 May 1543) was the first astronomer to formulate a comprehensive heliocentric cosmology, which displaced the Earth from the center of the universe. His epochal book, De revolutionibus orbium coelestium (On the Revolutions of the Celestial Spheres), published in 1543 just before he died, is often regarded as the starting point of modern astronomy and the defining epiphany that began the Scientific Revol...