September 12, 2006 image of astronaut Joseph R. Tanner, STS-115 mission specialist, waves toward the digital still camera of his space walk colleague, astronaut Heidemarie M. Stefanyshyn-Piper as the two share extravehicular activity (EVA) duties during the first of three scheduled spacewalks. The STS-115 astronauts and Expedition 13 crew worked on construction of the International Space Station.