.bigstock.com Photograph by James Tagg Illustrated by James Tagg saichol chandee, www.shutterstock. com Kind permission Steinn Sigurdsson (1991) Eugéne Pirou, Wikimedia, PD Reto Stéckli, NASA Earth Observatory zentilia, www.bigstock.com Credit NASA Weisstein, Eric W. “Cellular Automaton.” From MathWorld