Operating Discovery's robotic arm, Thomas grappled the "crate" full of equipment racks and supplies at 9:37 p.m. Sunday, lifting it out of the shuttle's cargo bay at 10:10 p.m. Over the course of the next two hours, he slowly and deliberately moved the 11-ton module into place. At 12:02 a.m. today, STS-102 Commander Jim Wetherbee commanded the latches on the station's Earth-facing Common Berthing Mechanism to establish a tight seal with the Leonardo module.
The berthing of Leonardo to Unity took slightly longer than planned while Expedition One Commander Bill Shepherd rerouted video from the Centerline Berthing Camera System to the television monitors on the shuttle's aft flight deck so that Thomas could use the view looking directly out the berthing port at its corresponding opening on Leonardo. There also was a delay in activating the cargo carrier while Shepherd connected a Unity-to-Destiny power cable that provides electricity to systems inside Leonardo. Shepherd briefly entered the Leonardo module at 5:51 a.m. to retrieve the cable. He took it to the vestibule between the U.S. laboratory and Unity and made the required connections. Leonardo carries more than five tons of equipment and experiments that will be unloaded during the next few days before it is again detached from the station and stowed aboard Discovery to return to Earth.
The shuttle and station crews rejoined each other at 9:15 p.m. Sunday when the hatches separating them during the previous day's record-setting 8-hour, 56-minute space walk were reopened. With the hatches open, Jim Voss - the station's newest resident after a 10:45 p.m. swap-out with Sergei Krikalev - joined Expedition One Commander Bill Shepherd and Expedition Two Commander Yury Usachev on board the station. Only one more crew swap remains to complete the station's change of watch. Expedition One Commander Bill Shepherd will trade places with Expedition Two Flight Engineer Susan Helms on Tuesday. The hatches were closed once again at 5:39 a.m. today after 8 hours, 24 minutes. So far, the hatches between the shuttle and station have been open for a total of 10 hours, 27 minutes.
Meanwhile mission specialists Paul Richards and Thomas, with help from Helms, checked out the space suits they will wear for a planned 6-hour, 30-minute space walk scheduled to begin at 10:47 p.m. Monday. Richards and Thomas will finish up a task that was deferred from the first space walk, connecting cables on the Lab Cradle Assembly that will be the mounting location for the station's robotic arm when it arrives next month. Next, they'll install an External Stowage Platform on the hull of Destiny and hook up cables that will provide heater power to spare equipment that will be stored there. They'll place the first of such spares, a Pump and Flow Control Subassembly that regulates ammonia coolant flow, on the platform. The pair also will inspect the Floating Potential Probe that is designed to measure the electrical charge on the outside of the station but has not been providing data since being temporarily shut down for repositioning of the station's Soyuz escape vehicle in February.
Discovery and the International Space Station remain in excellent condition at an altitude of about 235 statute miles.