Clavius' cosmology. Diagram showing the layout of the universe as propounded by Christopher Clavius (1538-1612), the German astronomer. This is a staunchly geocentric universe. At the centre is Earth, around which orbit the Moon, Mercury, Venus, the Sun, Mars, Jupiter and Saturn. Beyond these are the vault of the fixed stars. This woodcut illustration comes from Disquisitiones mathematicae by Christoph Scheiner, published at Ingolstadt in 1614.