Astronauts aboard the international space station say the failure of a stabilizing gyroscope is not a crisis. The orbiting outpost is now operating with the minimum number of gyroscopes.
The U.S. space agency NASA says the gyroscope failed Wednesday, shortly after a new Russian-U.S. crew arrived with a temporary Dutch companion.
The station's gyroscopes are spinning wheels of about one meter diameter whose momentum keeps the spacecraft in a stable position. The station originally had four, but one broke down two years ago and has never been replaced. Delivery of a new one has been delayed because of the grounding of the U.S. space shuttle fleet for safety upgrades after the orbiter Columbia accident.
The failure of the second gyroscope Wednesday leaves the outpost with only two, the fewest necessary to maintain its steady position. But NASA officials say if another goes bad, the station will maintain stability by firing jet thrusters. This uses extra fuel.
Outgoing station commander Michael Foale told reporters Friday that he feels no anxiety about the situation.
"The thrusters are perfectly fine and in good working order and there is fuel on board, enough, I think I read, for maybe six to 12 months," he said. "So there is no crisis involved in this whatsoever. It's more a matter of how do you plan this, what's the best way to do it, details like that that need to be worked out."
Mr. Foale says engineers believe the problem is not with the gyroscope itself, but with a remote controlled electronic circuit breaker on the outside of the station. Its repair would require a spacewalk.
"If that's the case, it really makes the problem that much easier to solve without launching more equipment," said Michael Foale. "It does involve a spacewalk and I think probably it's going to be the next crew that does that spacewalk at some point."
The next crew is cosmonaut Gennady Padalka, the new space station commander, and U.S. astronaut Mike Fincke, who are spending several days with the old team before taking command. They were already scheduled to perform two spacewalks during their six-month stay to maintain the Russian module and to prepare the station's exterior for next year's docking of a new European Space Agency cargo vehicle.
Mr. Fincke says he is prepared to fix the gyroscope electronics during a spacewalk, if required.
"We don't know if they are going to actually really ask us to go out, but if they do, I'll let you know right away that I've been trained by the best instructors, both in Houston and in Moscow, and we're ready for whatever comes," he said.
Astronaut Fincke and cosmonaut Padalka were joined on the Russian Soyuz spacecraft flight to the station by Dutch astronaut Andre Kuipers. He is conducting European experiments aboard the outpost before returning to Earth next week with Michael Foale and cosmonaut Alexander Kaleri.