STS-110 Commander Michael Bloomfield talks to members of the Closeout Crew in the White Room before he enters entering Space Shuttle Atlantis for launch. The White Room provides entry into the cockpit area of the orbiter. This is Bloomfield's third Shuttle flight. STS-110 is carrying the S0 Integrated Truss Structure and Mobile Transporter (MT) on this 13th assembly flight to the International Space Station. On the 11-day mission, astronauts will make four spacewalks to attach the S0 truss, which will become the backbone of the Space Station, to the U.S. Lab, "Destiny." The MT, a space "railcar," is attached to the truss segment and will make its debut run during the flight. Launch is scheduled for 4:40 p.m. EDT (20:40 GMT)