The competing gravitational pull between celestial bodies creates a vast array of low-energy passageways that winds around the sun, planets and moons. Space travel along these corridors would slash the amount of fuel needed to explore and develop our solar system. We have shown how to identify and traverse these passageways, which are associated with Lagrange points, regions of balance near a planet or moon. We have laid the groundwork for a new kind of space transportation architecture for the exploration of Mars, the asteroids, and the outer solar system, including a mission to assess the possibility of life on Jupiter's icy moons.