KENNEDY SPACE CENTER, Fla. — A critical computer aboard Mir shut down Saturday, just three days before space shuttle Discovery's scheduled liftoff on a ferry flight to the Russian space station.
The computer failure disabled Mir's motion-control system, and the space station was orbiting Earth with its solar panels improperly aimed, NASA spokesman Kyle Herring said from Moscow. The panels must face the sun to generate electricity.
Flight controllers told the three-man crew to turn on the attached Soyuz capsule so its thrusters could be used to steer the station and realign the panels. The two cosmonauts and one astronaut also turned off their air conditioner, lights and other nonessential equipment to conserve power.
Despite the problem, the countdown began as planned here late Saturday for a Tuesday launch by Discovery.
Last year, computers continually shut down aboard the craft, causing power outages, but it's the first time in five months that Mir's motion-control computer has crashed.
"We've seen this several times before, so it's something that the flight control team knows how to deal with," Herring said.
Similar computer failures have taken just a day or two to fix, plenty of time before Discovery is due to take off, Herring said. Russian space officials suspected the problem is with the computer's software and can be fixed quickly, possibly by tonight.
This will be the ninth and final time a shuttle links up with the aging Russian space station. The main objective is to pick up U.S. astronaut Andrew Thomas, who has been living on Mir since January.
"There doesn't seem to be a whole lot of alarm out there," Herring said. "They're just going through a methodical evaluation to see what they need to know to recover from it."