KENNEDY SPACE CENTER, FLA. - Inside the payload changeout room on Launch Pad 39B, STS-121 Mission Specialist Lisa Nowak takes a close look at part of the payload for the mission. She is dressed in a clean room suit, appropriate for the environmentally clean or "white room" condition in which the payload resides before being transferred to the shuttle's payload bay. The payload includes the multi-purpose logistics module Leonardo, which is carrying supplies and equipment for the International Space Station, the lightweight multi-purpose experiment support structure carrier and the integrated cargo carrier. Crew members are at NASA's Kennedy Space Center for Terminal Countdown Demonstration Test activities, which include equipment familiarization and a simulated launch countdown. Mission STS-121 is scheduled for launch on Space Shuttle Discovery on July 1.