... Credit: STS-126 Shuttle Crew , NASA Explanation: Where's the astronaut? Somewhere in this impressive array of International Space Station (ISS) hardware, astronaut Steve Bowen can be found upgrading and cleaning key parts of Earth's most prominent orbital outpost. Astronaut Bowen and Heidemarie Stefanyshyn-Piper (not pictured), part of the Space Shuttle Endeavour 's recently ended STS-126 mission to the ISS, spent nearly three hours on this spacewalk hovering high above planet Earth. ...