Astronomy Picture of the Day

Explanation: What's that astronaut doing? Unloading a space shuttle -- for the last time. After the space shuttle Atlantis docked with the International Space Station (ISS) last week, astronaut 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. On Earth, the RRM box would have the weight of about three people and be much more difficult to carry. Pictured above on the far left, DEXTRE prepares to help move a failed space pump back to Atlantis. Visible behind the astronaut is the space station's Kibo Experimental Module. The much awaited final shuttle return flight is currently scheduled for 5:56 am EDT Thursday, July 21.