Astronaut Peggy Whitson a member of the Expedition 5 crew looks over equipment in the Space Station Processing Facility.

Astronaut Peggy Whitson, a member of the Expedition 5 crew, looks over equipment in the Space Station Processing Facility. She and other crew members Commander Valeri Korzun and Sergei Treschev will be traveling to the International Space Station on mission STS-111 and will be replacing the Expedition 4 crew. Part of the payload on STS-111 will be the Mobile Base System, to be installed installed on the Mobile Transporter to complete the Canadian Mobile Servicing System, or MSS. The mechanical arm will then have the capability to "inchworm" from the U.S. Lab fixture to the MSS and travel along the Truss to work sites. STS-111 is scheduled to launch in May 2002