In this 1545 depiction of Aristotelian cosmology, Petrus Apianus shows a stationary Earth at the center of the universe, surrounded by seven concentric "crystalline" spheres, which carry the sun, the moon, and the planets.
Reproduced from the collections of the Library of Congress
Ivars Peterson is a freelance writer and editor. He was Director of Publications at the Mathematical Association of America from 2007 to 2014. As an award-winning mathematics writer, he previously worked at Science News for more than 25 years and served as editor of Science News Online and Science News for Kids. His books include The Mathematical Tourist, Islands of Truth, Newton's Clock, and Fragments of Infinity: A Kaleidoscope of Math and Art.