JSC2012-E-237433 (7 Nov. 2012) --- European Space Agency astronaut Alexander Gerst, Expedition 40/41 flight engineer, attired in a training version of his Extravehicular Mobility Unit (EMU) spacesuit, awaits the start of a spacewalk training session in the waters of the Neutral Buoyancy Laboratory (NBL) near NASA's Johnson Space Center. Photo credit: NASA