We study the natural satellites (moons) of planets, starting with a survey of our own solar system, and introduce the principles and theories of their formation and evolution. How do Galilean satellites form? What causes Triton’s plumes? Is the Saturn system young? How old is the Moon? Why are binary asteroids and KBOs so common? Is Phobos falling apart? Then we will consider the science questions motivating current and planned missions of exploration, and the discovery of exomoons. The class will emphasize quantitative approaches and will therefore rely upon a common understanding of mechanics and calculus. Familiarity with geology is helpful but is not required. May be co-convened with PTYS 523.