But Weather Threatens Oft-Delayed Shuttle Flight

We're at less than two days and counting for first available launch opportunity for the space shuttle Atlantis, on its twice-delayed mission to the International Space Station. Liftoff is scheduled for Thursday at 1445 EST, according to NASA.

Mission Management Team Chairman Leroy Cain said Atlantis and its European-built Columbus laboratory look good for the mission. "The team is in great shape and we're ready to move forward," Cain said.

If only the Florida wintertime weather were so cooperative. The current forecast pegs the chances of acceptable conditions for launch at a mere 40 percent, with showers and thunderstorms threatening to last into the weekend.

For the moment, at least, the launch is still a "go." Launch director Doug Lyons told The Associated Press the countdown is proceeding without issues, and "we're hoping it will stay that way."

"We're all thinking that Thursday's the day regardless of what the weather guy might tell you," he added.

Also keeping their fingers crossed are Mission Commander Steve Frick and Pilot Alan Poindexter, who started the day Tuesday practicing landing the shuttle in the Shuttle Training Aircraft -- a specially-outfitted Gulfstream II bizjet outfitted with a combination of modifications to the exterior, and a complex suite of computers, to make the transformation from everyday jet-handling to that of a 110-ton falling brick -- er, orbiter.

Meanwhile, the five mission specialists for the flight are also spending full days with checklists and practicing their flight tasks. They have simulators at their disposal that let them rehearse the complex duties required in orbit.

Astronaut Leland Melvin, for example, will operate the robot arm on the International Space Station during the mission to move the Columbus laboratory out of Atlantis' payload bay and attach it to the station. So he can rehearse with a simulator in the Astronaut Crew Quarters that is set up with the same kind of controllers he will use on the station.

As the lead spacewalker on three EVAs, Rex Walheim goes into space with a lot of checklists. One of the spacewalks will include astronaut Stanley Love, who will also help Melvin with the space station's robot arm.

Because the astronauts will be working with two long robot arms during spacewalks in which two astronauts are outside the station, each move is highly choreographed and carefully practiced. It routinely takes months of rehearsal before the actual duties are carried out in space.

The crew also includes European Space Agency astronauts Hans Schlegel of Germany and Leopold Eyharts of France. Both have a list of duties for activating the Columbus lab, which was made in Europe and is ESA's primary contribution to the space station project.

Schlegel will conduct two spacewalks during the flight to connect power and fluid lines between Columbus and the station.

Eyharts will become Europe's first long-duration station resident. He will take the place of NASA astronaut Dan Tani.

FMI: www.nasa.gov/shuttle