Nicolaus Copernicus was a mathematician and astronomer whose genius sparked the Scientific Revolution. In his work 'De revolutionibus orbium coelestium' (On the Revolutions of the Heavenly Spheres), he challenged the 1,500-year-old belief that the Earth was the center of the universe. Copernicus proposed the heliocentric model, which placed the Sun at the center with Earth and other planets orbiting it. This was a radical shift in human thought, removing Earth from its 'special' status. Although his model still used circular orbits (later corrected by Kepler), Copernicus provided the mathematical foundation that allowed later scientists like Galileo and Newton to build our modern understanding of the cosmos.