The Aristotelian Universe as Imagined in the Sixteenth Century A round earth is at the center, surrounded by spheres of water, air, and fire. Beyond this small nucleus, the moon, the sun, and the five planets were embedded in their own rotating crystal spheres, with the stars sharing the surface of one enormous sphere. Beyond, the heavens were composed of unchanging ether.
(From Cosmographia, by Peter Apian, 1630/Universal History Archive/UIG/Bridgeman Images)