The Mobile Base System (MBS), parked overnight on the station's robotic arm about three feet from installation, has had a chance to receive the proper thermal conditioning to match the temperatures on the Mobile Transporter, the actual railcar on the truss itself. Operated by Expedition Five Flight Engineer Peggy Whitson and Endeavour Astronaut Carl Walz, the space station robotic arm will mate the MBS platform to the railcar and flight controllers on the ground will command latches to close to secure the platform in place. Eventually, the station arm will "walk off" its current base location on the Destiny Laboratory to the MBS and ride the railway to move up and down the entire length of the station.
The 10 astronauts and cosmonauts on the Shuttle/Station complex will also continue their transfer of equipment and supplies to the station from the Leonardo Multi-Purpose Logistics Module.
Endeavour's crew - Commander Ken Cockrell, Pilot Paul Lockhart, Mission Specialists Philippe Perrin and Franklin Chang-Díaz, and former station residents Yury Onufrienko, Walz and Dan Bursch - were awakened at 4:23 a.m. Central time to "I Only Have Eyes for You" by the Flamingoes, from the American Graffiti soundtrack which was selected for Lockhart.
Although Expedition Five crewmembers Whitson, Commander Valery Korzun and Flight Engineer Sergei Treschev have been in charge of ISS operations since Friday afternoon, an official change of command ceremony between Expedition crews will occur early this afternoon.
The crews will also participate late today in a review of procedures for tomorrow's second spacewalk by Chang-Díaz and Perrin to hook up cables between the Mobile Base System and the Mobile Transporter and to bolt the two components together. Systems on both Endeavour and the ISS continue to function normally as the two craft orbit the Earth every 90 minutes at an altitude of about 240 statute miles.