Solar Electric Propulsion (SEP)

NASA's Solar Electric Propulsion (SEP) project is developing critical technologies to enable cost-effective new trips to Mars and to asteroids across the inner solar system, and also to support a variety of commercial spaceflight activities. Energized by the electric power from on-board solar arrays, the electrically propelled system will use 10 times less propellant than a comparable, conventional chemical propulsion system -- such as those used to power the space shuttles to orbit. Yet that reduced fuel mass will deliver robust power capable of propelling scientific missions well beyond low-Earth orbit, sending exploration spacecraft to distant destinations or ferrying cargo to and from points of interest, laying the groundwork for new missions or resupplying those already under way.