Expedition 24 crew members Tracy Caldwell and Doug Wheelock during ISS EVA 1 91027 training

JSC2009-E-226231 (28 Oct. 2009) --- Attired in a training version of his Extravehicular Mobility Unit (EMU) spacesuit, astronaut Doug Wheelock, Expedition 24 flight engineer and Expedition 25 commander, is about to be submerged in the waters of the Neutral Buoyancy Laboratory (NBL) near NASA's Johnson Space Center. Divers (out of frame) are in the water to assist Wheelock in his rehearsal, which is intended to help prepare him for work on the exterior of the International Space Station.