KENNEDY SPACE CENTER, FLA. - In the Space Station Processing Facility, the multi-purpose logistics module Leonardo moves above the payload transportation canister. The module will be lowered into and installed in the canister for transfer to Launch Pad 39B. At the pad, the module will be installed in Space Shuttle Discovery's payload bay. Part of the payload for mission STS-121, Leonardo carries tons of supplies and experiments for the International Space Station and its crew. Discovery is scheduled to be launched in a window that extends from July 1 to July 19. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. - In the Space Station Processing Facility, the multi-purpose logistics module Leonardo is lowered next to the Integrated Cargo Carrier inside the payload transportation canister for transfer to Launch Pad 39B. At the pad, the module and carrier will be installed in Space Shuttle Discovery's payload bay. Part of the payload for mission STS-121, Leonardo carries tons of supplies and experiments for the International Space Station and its crew. Discovery is scheduled to be launched in a window that extends from July 1 to July 19. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. - In the Space Station Processing Facility, the multi-purpose logistics module Leonardo is moved by crane across the building to the payload transportation canister for transfer to Launch Pad 39B. At the pad, the module will be installed in Space Shuttle Discovery's payload bay. Part of the payload for mission STS-121, Leonardo carries tons of supplies and experiments for the International Space Station and its crew. Discovery is scheduled to be launched in a window that extends from July 1 to July 19. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. - In the Space Station Processing Facility, the multi-purpose logistics module Leonardo is moved away from its workstand. The module is being moved to the payload transportation canister for transfer to Launch Pad 39B, where it will be installed in Space Shuttle Discovery's payload bay. Part of the payload for mission STS-121, Leonardo carries tons of supplies and experiments for the International Space Station and its crew. Discovery is scheduled to be launched in a window that extends from July 1 to July 19. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. - In the Space Station Processing Facility, the multi-purpose logistics module Leonardo is lowered next to the Integrated Cargo Carrier inside the payload transportation canister for transfer to Launch Pad 39B. At the pad, the module and carrier will be installed in Space Shuttle Discovery's payload bay. Part of the payload for mission STS-121, Leonardo carries tons of supplies and experiments for the International Space Station and its crew. Discovery is scheduled to be launched in a window that extends from July 1 to July 19. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. - In the Space Station Processing Facility, workers attach an overhead crane to the multi-purpose logistics module Leonardo, which is being moved to the payload transportation canister for transfer to Launch Pad 39B, where it will be installed in Space Shuttle Discovery's payload bay. Part of the payload for mission STS-121, Leonardo carries tons of supplies and experiments for the International Space Station and its crew. Discovery is scheduled to be launched in a window that extends from July 1 to July 19. Photo credit: NASA/Kim Shiflett

KENNEDY SPACE CENTER, FLA. - In the Space Station Processing Facility, the multi-purpose logistics module Leonardo is lifted by crane off a workstand. The module is being moved to the payload transportation canister for transfer to Launch Pad 39B, where it will be installed in Space Shuttle Discovery's payload bay. Part of the payload for mission STS-121, Leonardo carries tons of supplies and experiments for the International Space Station and its crew. Discovery is scheduled to be launched in a window that extends from July 1 to July 19. Photo credit: NASA/Kim Shiflett