JSC2010-E-196894 (20 Dec. 2010) --- NASA astronauts Doug Hurley (left), STS-135 pilot; Rex Walheim and Sandy Magnus, both mission specialists, attired in training versions of their shuttle launch and entry suits, participate in a post insertion/de-orbit training session on the flight deck of the crew compartment trainer (CCT-2) in the Space Vehicle Mockup Facility at NASA's Johnson Space Center. STS-135 is planned to be the final mission of the space shuttle program. Photo credit: NASA or National Aeronautics and Space Administration