2002 News Releases

A "freeway" through the solar system resembling a vast array of virtual winding tunnels and conduits around the Sun and planets, as envisioned by an engineer at NASA's Jet Propulsion Laboratory, Pasadena, Calif., can slash the amount of fuel needed for future space missions.

Called the Interplanetary Superhighway, the system was conceived by Martin Lo, whose software was used to help design the flight path for NASA's Genesis mission, which is currently using this "freeway in space" on its mission to collect solar wind particles for return to Earth.

Most missions are designed to take advantage of the way gravity pulls on a spacecraft when it swings by a body such as a planet or moon. Lo's concept takes advantage of another factor, the Sun's pull on the planets or a planet's pull on its nearby moons. Forces from many directions nearly cancel each other out, leaving paths through the gravity fields in which spacecraft can travel.

Each planet and moon has five locations in space called Lagrange points, where one body's gravity balances another's. Spacecraft can orbit there while burning very little fuel. To find the Interplanetary Superhighway, Lo mapped some possible flight paths among the Lagrange points, varying the distance the spacecraft would go and how fast or slow it would travel. Like threads twisted together to form a rope, the possible flight paths formed tubes in space. Lo plans to map out these tubes for the whole solar system.

Lo's research is based on theoretical work begun in the late nineteenth century by the French mathematician Henri Poincar