The Leonardo module is lifted out of Discovery's payload bay by the shuttle roboto arm. Photo: Spaceflight Now/NASA TV

Astronaut Andrew Thomas, operating the shuttle Discovery's 50-foot-long robot arm, gently lifted a $150 million Italian-built cargo carrier from the shuttle's cargo bay and successfully attached it to the international space station early today.

"And just one word for Andy: Oustanding!" astronaut Gerhard Thiele radioed from mission control in Houston.

"Thank you, Gerhard; we aim to please," Thomas replied.

The Leonardo module, loaded with 9,663 pounds of equipment and supplies, was unberthed at 11:10 p.m. and slowly maneuvered into position for attachment to the downward facing port of the station's multi-hatch Unity module.

Moving at a glacial pace, Thomas completed the operation two hours later at 1:02 a.m. Hatches leading into the Leonardo mini pressurized logistics module, or MPLM, should be open by 7 a.m. or so.

"Everybody on the station side has big smiles on their faces to have the new MPLM up there," Thiele called.

"Well good, thank you," commander James Wetherbee replied from Discovery. "The team did a great job up here and down there. Thanks for your help."

Station commander William Shepherd ran into problems activating Leonardo's internal systems. After a bit of troubleshooting, ground controllers realized a critical electrical jumper needed to route power to the module had not yet been installed.

Shepherd quickly confirmed that, saying "if they can get in the database and tell us where to find a jumper, we can fix that fairly quickly."

"And we're working that as we speak," replied Stephanie Wilson from the space station control center. "Stand by."

A few moments later, Wilson told Shepherd the jumper in question was located inside the Leonardo module. Once the jumper is installed, fans can be activated to prevent pockets of carbon dioxide from building up.

"So at this time, you are 'go' to ingress," Wilson said around 6:15 a.m. "Please monitor your symptoms as you do so. And I have a rack and section location for the jumper when you're ready to copy."

Hatches between Discovery and the space station, meanwhile, closed Saturday in preparation for an overnight spacewalk, were re-opened at 10:15 p.m. Sunday evening to permit a second member of the station's crew to be replaced.

Illustration of Leonardo being attached to Unity. Photo: Spaceflight Now/NASA TV

The primary goal of the 103rd shuttle mission is to replace the station's first three-man crew, known as Expedition One, with three fresh crew members.

Expedition Two commander Yury Usachev moved aboard early Saturday, replacing cosmonaut Yuri Gidzenko, who is now considered a member of Discovery's crew.

The first item on the agenda Sunday evening was to move a custom seat liner for astronaut James Voss into the station's Soyuz lifeboat. Installation of the seat liner at 11:45 p.m. marked the official transfer of Voss to the space station crew.

Astronaut Susan Helms will replace Expedition One commander Shepherd on Wednesday. Discovery's planned touchdown March 20 will close out a 140-day stay in space for Shepherd and his crewmates. Usachev and company will return to Earth aboard a shuttle in July.

With the transfer of Voss complete, hatches between Discovery and the station were closed again at 6:39 a.m. in preparation for a second and final spacewalk overnight Monday to install a storage platform on the station's hull and to hook up cables that will carry video and data from the station's robot arm to computer workstations inside the Destiny lab module.

The spacewalk by Thomas and Paul Richards is expected to last about six-and-a-half hours.

Leonardo as it neared the station docking port. Photo: Spaceflight Now/NASA TV

Over the next five days, the Discovery and space station crew will unload Leonardo, moving experiment racks, supplies and other equipment into the lab complex.

"And some of that equipment's very important," Thomas said in a NASA interview. "For example, we're carrying the robotics workstation for the international space station. This is the system of video monitors, computers and hand controls that will enable operators to actually run the space station robotic arm when it comes up (in April), so it's a very important piece of equipment.

"They will be transferring that and doing some checkout of that equipment," he continued. "They'll be transferring a DC-to-DC converter unit that's in one of the racks that will be providing power for the lab module. Obviously, that's a very important thing to have.

"There [are] a lot of tools, logistics, water transfer equipment. There's a cycle ergometer exercise system that has to go across and things like that.

"So, they're going to be very busy getting all of that equipment across," he said. "And some of it needs to be done fairly promptly because we want them to have it on board for a while and operational so that we can confirm that the equipment we've brought is functional and that it is able to be left there."

If all goes well, Leonardo will be undocked from the station March 17 and reberthed in Discovery's cargo bay, loaded with about one ton of trash and no-longer-needed equipment.

Discovery's landing back at the Kennedy Space Center is targeted for 2 a.m. March 20, two minutes earlier than NASA's most recent previous estimate.