1598-1671

Italian astronomer who discovered the first double star (1643) and proved instrumental in undermining Aristotelian cosmology. In Almagestum novum (1651) he maintained the identity of celestial and terrestrial matter and thus the corruptibility of the heavens. Riccioli also departed from traditional cosmology in two important ways: viewing the world's center as the cosmos's noblest place and making Earth more noble and perfect than any celestial body. Riccioli deployed these ideas in challenging Nicolaus Copernicus's claim that the Sun occupied the cosmos's geometric center.