STS-121 Mission Specialist Stephanie Wilson and Pilot Mark Kelly walk across the Shuttle Landing Facility.

STS-121 Mission Specialist Stephanie Wilson and Pilot Mark Kelly walk across the Shuttle Landing Facility after their arrival to get ready for launch on July 1. The launch will be Wilson's first space flight. During the 12-day mission, the STS-121 crew will test new equipment and procedures to improve shuttle safety, as well as deliver supplies and make repairs to the International Space Station. This mission is the 115th shuttle flight and the 18th U.S. flight to the International Space Station. Photo credit: NASA/Kim Shiflett