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CloudsSpace shuttle Discovery astronauts took three space walks to upgrade the International Space Station and test emergency repairs.
During the first space walk Astronaut Piers J. Sellers hangs from the bottom of a 100-foot Remote Manipulator System/Orbiter Boom Sensor System. The astronauts successfully tested the space crane that will allow them to reach new locations on the space shuttle or International Space Station. See more Discovery photos.
Space station upgrades
During the second space walk, which lasted for almost seven hours, astronauts Michael E. Fossum (center) and Piers J. Sellers (you can see his backpack right) repaired the Mobile Transporter rail car and delivered a spare pump module for the International Space Station.