One of the aircraft carrying STS-123 crewmembers begins the taxi to the runway for takeoff on the return trip to Houston.

At the NASA Kennedy Space Center's Shuttle Landing Facility, one of the aircraft carrying STS-123 crewmembers begins the taxi to the runway for takeoff on the return trip to Houston. The STS-123 crew members took part in a terminal countdown demonstration test, or TCDT, in preparation for the launch of space shuttle Endeavour scheduled on March 11. The TCDT enables astronauts and ground crews to participate in various countdown activities, including equipment familiarization and emergency egress training. On the STS-123 mission, Endeavour and its crew will deliver the first section of the Japan Aerospace Exploration Agency's Kibo laboratory and the Canadian Space Agency's two-armed robotic system, Dextre Photo credit: NASA/Kim Shiflett