A concept image shows NASA's next generation crew launch vehicle, the Ares I, during ascent. Ares I is an in-line, two-stage rocket configuration topped by the Orion crew exploration vehicle and launch abort system. The Ares I first stage is a single, five-segment reusable solid rocket booster, derived from the space shuttle. Its upper stage is powered by a J-2X engine, similar to those used in the Apollo program. Ares I will carry the Orion with its crews of up to six astronauts to Earth orbit, where they would dock with a lunar module and earth departure stage before leaving for the moon.