A crew transport vehicle approaches space shuttle Discovery on the Shuttle Landing Facility at NASA's Kennedy Space Center.

A crew transport vehicle, or CTV, approaches space shuttle Discovery on the Shuttle Landing Facility at NASA's Kennedy Space Center. Discovery landed on Runway 15, ending the 14-day, STS-124 mission to the International Space Station. Discovery has been purged -- providing cool and humidified air conditioning to the payload bay and other cavities to remove any residual explosive or toxic fumes – while still on the runway. Cooling transfer to ground services occurs at about the same time, allowing onboard cooling to be shut down. When it is determined that the area in and around the orbiter is safe, the crew will departure from the orbiter to the CTV. The STS-124 mission delivered the Japan Aerospace Exploration Agency's large Japanese Pressurized Module and its remote manipulator system to the space station. Photo credit: NASA/Kim Shiflett