The STS-100 crew strides out of the Operations and Checkout Building on their way to the Astrovan and Launch Pad 39A. From front to back are Pilot Jeffrey S. Ashby and Commander Kent V. Rominger; Mission Specialists Yuri V. Lonchakov and Chris A. Hadfield, Umberto Guidoni and John L. Phillips, with Scott E. Parazynski waving at the rear. At the pad they will take part in a simulated launch countdown. The mission is carrying the Multi-Purpose Logistics Module Raffaello and the SSRMS, to the International Space Station. Raffaello carries six system racks and two storage racks for the U.S. Lab. The SSRMS is crucial to the continued assembly of the orbiting complex. Launch of mission STS-100 is scheduled for April 19 at 2:41 p.m. EDT from Launch Pad 39A