Astronauts Terry Virts and Samantha Cristoforetti

JSC2012-E-238476 (21 Nov. 2012) --- NASA astronaut Terry Virts (left) and European Space Agency astronaut Samantha Cristoforetti, both Expedition 42/43 flight engineers, attired in training versions of their Extravehicular Mobility Unit (EMU) spacesuits, participate in a spacewalk training session in the waters of the Neutral Buoyancy Laboratory (NBL) near NASA's Johnson Space Center. Divers are in the water to assist Virts and Cristoforetti in their rehearsal, which is intended to help prepare them for possible work on the exterior of the International Space Station. Photo credit: NASA