This article presents an applied calculus exercise that can be easily shared with students. One of Kepler's greatest discoveries was the fact that the planets move in elliptic orbits with the sun at one focus. Astronomers characterize the orbits of particular planets by their minimum and maximum distances to the sun, known respectively as the perihelion and aphelion. In this article, the author raises the more sophisticated mathematical question: What is the true average distance of a planet from the sun? More generally, he asks: For any ellipse, what is the true average distance from all points P(x, y) on the ellipse to a particular focus, (c, 0)? (Contains 2 figures.)