That's It, No More Backups

One day after the new tenants arrived aboard the International Space Station, NASA says a second of four critical gyroscopes used to stabilize the station has failed. While the ISS can operate on just two gyros, the failure means there is no longer a margin of error.

"This is not a crew safety issue," NASA spokesman Kelly Humphries told ANN. "There are still two functining gyros on orbit and we have the Russian propulsion system (from the Soyuz spacecraft which is currently docked with the ISS) to maintain attitude."

NASA reports the gyro lost power at 2018 GMT Wednesday night (4:18 pm EDT). "What happened is something tripped a power switch," said Humphries. "It's been off since then. But we believe the gyro is okay."

One of the gyros failed during Expedition 6, Humphries said. While the station can operate on as few as two gyros without beginning to tumble, one of the two still-functioning gyros has been signalling trouble lately, indicating that it's not getting enough lubrication, he said.

"The crew was informed about the failure during their (Thursday) morning briefing," Humphries said, speaking by phone from the Johnson Space Center in Houston (TX). "They voiced confidence that this can be repaired."

Just how the gyro can be repaired, however, remains an issue. Crew members could perform a space walk to get to the gyro's power control unit. But there's a problem: Space rookie Michael Fincke's Russian space suit won't fit through the US airlock, which is closest to the area in question. And his Russian suit isn't altogether aboard yet.

"He needs gloves, I think," said Humphries. "They're not due until the next resupply mission. There are complete suits on board the station, but they're not fitted specifically for Fincke."

Even with the gloves, Fincke, along with mission commander Gennady Padalka, would have to exit the station from the Russian airlock, much further away from the area where the gyroscope's power module is located.

Humphries said American and Russian controllers and scientists are "exploring options" right now and have not yet decided how they will address the issue of the second failed gyroscope. He had no idea when any decisions would be made or what options were under consideration.

FMI: www.spaceflight.nasa.gov/station