Geocentric model of the universe. Illustration of the Earth-centred (geocentric) Ptolemaic model of the heavens. This system is known through the Almagest of the Egyptian-Greek astronomer Ptolemy, of the 2nd century. His work summarized 500 years of Greek astronomy and this model of the heavens owes much to work by Hipparchus. The Moon, the Sun and the five known planets (Mercury, Venus, Mars, Jupiter and Saturn) inhabited a series of perfect, Earth-centred, rotating spheres (shown as circles here), ending in a sphere of stars. Later astronomers added more spheres to improve the model. However, inaccurate predictions led to it being overthrown by the 1543 Sun-centred (heliocentric) model of Copernicus. Unlabelled versions: C038/3784 and C038/3785. |