More Shuttle Trouble

[Christina]

HOUSTON (Reuters) - A major, new problem popped up on the International Space Station on Wednesday as space shuttle astronauts finished installing a new solar-power unit -- the failure of key computers that could in an extreme scenario force the crew off the station, officials said."That's not something I'm really concerned about," ISS program manager Mike Suffredini said of having to leave the station at least temporarily with no crew aboard. But "that's the worst-case scenario," he told a late night news briefing.The failure occurred in computers on the Russian segment of the 16-nation space station, computers that control navigation and key life-support systems on the huge orbital base. Without them, the station cannot maintain proper orbit and the crew cannot stay on board.The station relies mostly on big gyroscopes to maintain its proper orientation but also uses control jets and navigation systems run by the troubled computers to help.Similar station computer failures have occurred before, NASA officials said, but never affecting all three lines of Russian computers to the point that they could not reboot themselves, as happened Wednesday. The U.S. segment has its own computers but they depend on the Russian ones, officials said.Suffredini said he expects to be able to fix the problem and that there are numerous alternatives short of taking the crew off the station. "I'm not thinking this (is) something we will not recover from," he said.