A Busy Space Walk at the Space Station . ... ISS Expedition 28 Crew , STS-135 Crew , NASA Explanation: What's that astronaut doing? Unloading a space shuttle -- for the last time. After the space shuttle Atlantis docked with the Mike Fossum underwent a long spacewalk that included carrying a Robotics Refueling Mission (RRM) payload from Atlantis' cargo bay to a platform used by the space station's famous robot DEXTRE . ... NASA Web Site Statements, Warnings, and Disclaimers . ...