The Ares I-X roll control system module, comprising two modules and four thrusters, is being prepared for a fit check on the Ares I-X rocket upper stage simulator. The hardware is in high bay 4 of the Vehicle Assembly Building at NASA's Kennedy Space Center. The system is designed to perform a 90-degree roll after the rocket clears the launch tower, preventing a roll during flight and maintaining the orientation of the rocket until separation of the upper and first stages. The system module will return to earth and splash down; it will not be recovered. Ares I-X is the test vehicle for the Ares I, which is part of the Constellation Program to return men to the moon and beyond. Ares I-X is targeted for launch in summer of 2009. Photo credit: NASA/Tim Jacobs