Overview

The publication of Nicolaus Copernicus's (1473-1543) De Revolutionibus Orbium Celestium in 1543 was attended by no official opposition. The heliocentric system Copernicus presented was initially viewed as a hypothetical model devised merely to facilitate computation. For many, the most attractive feature of the new system was Copernicus's abolition of the equant, which restored uniform circular motion as the basic axiom of astronomy. Most early supporters passed over in silence the question of the system's physical reality. Theoretical improvements made possible by Copernican theory and new observations helped undermine Aristotelian physics and with it geocentrism—the idea that the Sun and all other planets in the Solar System revolved around Earth. By the mid-seventeenth century the heliocentric view reigned supreme, though...