STS-110 Mission Specialist Steven Smith relaxes during suit fit, which is part of Terminal Countdown Demonstration Test activities. The TCDT is held at KSC prior to each Space Shuttle flight to provide flight crews an opportunity to participate in simulated launch countdown activities. Scheduled for launch April 4, the 11-day mission will feature Shuttle Atlantis docking with the International Space Station (ISS) and delivering the S0 truss, the centerpiece-segment of the primary truss structure that will eventually extend over 300 feet