Workers keep close watch as it is lowered onto the crew module simulator for assembly.

In high bay 4 of the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida, workers keep close watch on the Ares I-X simulated launch abort system, or LAS, as it is lowered onto the crew module simulator for assembly. Ares I-X is the flight test vehicle for the Ares I, which is part of the Constellation Program to return men to the moon and beyond. Ares I is the essential core of a safe, reliable, cost-effective space transportation system that eventually will carry crewed missions back to the moon, on to Mars and out into the solar system. Ares I-X is targeted for launch in July 2009. Photo credit: NASA/Jack Pfaller