Stock Photo - Astronauts Dave Wolf (foreground with back to camera) and Mike Barratt assist astronaut Tom Marshburn with his extravehicular mobility unit spacesuit in the joint airlock, while astronaut Christopher Cassidy (almost out of frame at right) gets ready to join him. Marshburn and Cassidy were about to participate in the July 24 flight day 10 spacewalk. They are scheduled to wrap up the EVA work with a fifth overall session on July 27. The three STS-127 mission specialists and station flight engineer are part of a 13-member aggregation of astronauts and cosmonauts currently onboard the orbital outpost while its crew of six plays host to Endeavour's crew of seven.