STS-135 Mission Specialist Rex Walheim waves as he dons his launch-and-entry suit and helmet in the Operations and Checkout Building at NASA's Kennedy Space Center in Florida. Walheim is one of the final four astronauts to launch aboard a space shuttle. All three of Walheim's missions -- STS-110, STS-122 and now STS-135 -- will have been aboard space shuttle Atlantis. STS-135 is scheduled to lift off aboard Atlantis at 11:26 a.m. EDT on July 8 for a mission to the International Space Station.
STS-135 will deliver the Raffaello multi-purpose logistics module packed with supplies and spare parts for the orbiting outpost. Atlantis also will fly the Robotic Refueling Mission experiment that will investigate the potential for robotically refueling existing satellites in orbit. In addition, Atlantis will return with a failed ammonia pump module to help NASA better understand the failure mechanism and improve pump designs for future systems. STS-135 will be the 33rd flight of Atlantis, the 37th shuttle mission to the space station, and the 135th and final mission of NASA's Space Shuttle Program. For more information visit, www.nasa.gov/mission_pages/shuttle/shuttlemissions/sts135/index.html. Photo credit: NASA/Kim Shiflett