NASA's senior managers met Monday and set Discovery's last liftoff for next Monday. Launch time is 4:40 p.m.
This will be Discovery's 39th and final mission as NASA retires its three remaining shuttles. The White House wants NASA to focus on developing spaceships that can take astronauts out of orbit and into deep space.
As the launch team prepped Discovery for its flight to the International Space Station, Mission Control kept a wary eye on a piece of junk that was threatening to come dangerously close to the orbiting lab and its six inhabitants.
The unidentified object was projected to pass within one-tenth of a mile of the space station Tuesday morning.
If necessary, flight controllers could move the space station out of harm's way two hours beforehand.
Over the weekend, technicians replaced a pair of seals in a fuel line aboard Discovery that had been leaking. NASA said the repairs apparently solved the problem.
Engineers suspect contamination may have hampered the original seals. Mike Moses, a launch manager, said "it's a huge testament" to everyone who got Discovery ready for launch, given the hundreds of layoffs that struck the shuttle program at the beginning of October, with more to come as the shuttle program winds down.
Endeavour is scheduled to lift off at the end of February with a magnetic spectrometer for the space station.
That will be it, unless money is provided for one extra shuttle flight. If approved, Atlantis would close out the 30-year program.
Discovery and a crew of six will deliver a loaded storage bin to the space station and permanently install it.
The float-in closet includes a humanlike robot - from the torso up - that's known as Robonaut.
While Discovery's impending retirement did not come up at Monday's flight review, it was on the minds of many. Discovery, after all, is the shuttle fleet leader, first rocketing into orbit in 1984.
"It's going to be hard to see her retire," said launch director Mike Leinbach. "But we need to do what we need to do for the agency. So we'll get on with her final flight.
We'll make it the best one ever."