JSC2011-E-016282 (9 Feb. 2011) --- NASA astronaut Chris Ferguson, STS-135 commander, attired in a training version of his shuttle launch and entry suit, is pictured during a water survival training session in the Neutral Buoyancy Laboratory (NBL) near 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