BEIJING, June 14 (Xinhuanet) -- NASA says it's not worried about a failure of key computers Wednesday that occurred as Atlantis astronauts were installing a new solar-power unit, but the problem could force the crew off the International Space 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. Without them, the station cannot maintain proper orbit and the crew cannot stay on board.

    Big gyroscopes are mostly used to maintain the station's proper orientation but control jets and navigation systems run by the troubled computers can also be used 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.

    Engineers were studying whether the new solar power unit is the cause of the problem and whether disconnecting it to reboot the computers would resolve it.

    Space managers were also considering extending the visit of space shuttle Atlantis to use its attitude-control jets and life support to supplement the station's while engineers work on the problem.

    (Agencies)