JSC2011-E-040195 (2 March 2011) --- NASA astronaut Chris Ferguson, STS-135 commander, takes photos of the massive Vertical Motion Simulator (VMS) at NASA's AMES Research Center before the crew trains in the simulator on Wednesday, March 2, 2011, in Mountain View, Calif. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool

JSC2011-E-040193 (2 March 2011) --- NASA astronaut Chris Ferguson (left), STS-135 commander, confers with astronaut Rex Walheim, mission specialist, as the Atlantis crew participates in a briefing before a training session in the Vertical Motion Simulator (VMS) at NASA's Ames Research Center in Mountain View, Calif. March 2, 2011. Photo credit: NASA Photo/Houston Chronicle, Smiley N. Pool