Nicolaus Copernicus (1473-1543), Polish astronomer. Copernicus's heliocentric theory that the Earth orbited the Sun began the revolution that overthrew more than 1000 years of astronomical thought. A model of this theory is shown in his right hand (showing the Sun, Earth and Moon). In his left hand he is holding dividers, used to plot distances. Copernicus feared persecution by the Catholic Church, and delayed publication of his book 'The Revolution of the Heavenly Spheres' (1543) until near his death. Legend tells that he received his copy from the printers on the day he died. The book was banned by the Roman Catholic church from 1616 until 1835.