STS-112 Mission Specialist Sandra Magnus takes a break during emergency egress practice on the 195-foot level of the Fixed Service Structure, Launch Pad 39B. She and the rest of the crew are taking part in Terminal Countdown Demonstration Test activities, which include a simulated launch countdown. Mission STS-112 aboard Space Shuttle Atlantis is scheduled to launch no earlier than Oct. 2, between 2 and 6 p.m. EDT. STS-112 is the 15th assembly mission to the International Space Station. Atlantis will be carrying the S1 Integrated Truss Structure, the first starboard truss segment, to be attached to the central truss segment, S0, and the Crew and Equipment Translation Aid (CETA) Cart A. The CETA is the first of two human-powered carts that will ride along the ISS railway, providing mobile work platforms for future spacewalking astronauts.