The STS-121 crew are donning their orange launch and entry suits for launch today on Space Shuttle Discovery. Seated here is Mission Specialist Michael Fossum, who is making his first space flight. The launch is the 115th shuttle flight and the 18th U.S. flight to the International Space Station. 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. Photo credit: NASA/Kim Shiflett