Mission Specialist Nicole Stott tests the fit of her helmet before the launch countdown at NASA Kennedy Space Center's Launch Pad 39A.

STS-128 Mission Specialist Nicole Stott tests the fit of her helmet before the simulated launch countdown at NASA Kennedy Space Center's Launch Pad 39A. The countdown is the culmination of terminal countdown demonstration test activities to prepare the STS-128 crew for launch on space shuttle Discovery's STS-128 mission. Discovery will deliver 33,000 pounds of equipment to the station, including science and storage racks, a freezer to store research samples, a new sleeping compartment and the COLBERT treadmill. Launch is targeted for late August. Photo credit: NASA/Kim Shiflett