The International Space Station is ready to fly solo again.

NASA said Monday afternoon that Russian navigation computers that failed last week on the station passed a final test Monday morning. They were able to properly fire thrusters to keep the station in the right position.

That means that space shuttle Atlantis can undock Tuesday, with a return to Earth expected Thursday.

Hatches between the two craft should be closed before 6:30 p.m. EDT Thursday, and separation is set for 10:42 a.m. EDT Tuesday.

The computers, which also control oxygen production, crashed last week. All six of the computers' processors were back online Saturday.

The two processors that took longer to revive are now on standby mode and can be used if needed.

Except for an oxygen generator, all the space station systems that were powered down when the computers failed are now running.

When the computers failed, there were some concerns that if they could not be brought back online, at some point weeks or months down the road the station would have to be abandoned. Directional control is important, because it allows solar arrays to most efficiently capture energy from the sun.

It was thought that the installation of new panels this week had caused the computer problem.

Crew member Clayton Anderson will stay behind on the station, and Sunita Williams will return to Earth, days after setting a spaceflight record for women.