Heliocentric and geocentric models of the cosmos
By ticking the 'model' box, you can switch between the heliocentric model of the cosmos, introduced by Aristarchus of Samos (c. 310 BC -- c. 230 BC), and the geocentric model, based on deferents and epicycles, introduced by Apollonius of Perga (c. 240 BC -- c. 190 BC).
The illustration is based on actual distances.
Tick the 'traces' box to view the paths left by the planets.