Spacewalkers Peggy Whitson (R) and Dan Tani gather tools outside the International Space Station (ISS) after replacing a motor needed to move the station's solar array panels to follow the sun in this image from NASA TV January 30, 2008. (Xinhua/Reuters Photo) Photo Gallery>>>

    BEIJING, Jan. 31 (Xinhuanet) -- Two U.S. astronauts replaced a failed electric motor and gave the international space station a much-needed power boost, which added to the power margin at the orbiting outpost and cleared the way for deliveries of two science labs, media reports said Thursday.

    Hundreds of km up, space station commander Peggy Whitson and Daniel Tani Wednesday replaced a motor needed to tilt a solar wing toward the sun, taking extra precautions to avoid being shocked. Once the new motor was hooked up, electricity began flowing through the unit, and it checked out fine.

    "Yee-haw! Excellent," Whitson said.

Spacewalker Dan Tani works outside the International Space Station (ISS) with solar arrays in the background in this image from NASA TV January 30, 2008. Tani and spacewalker Peggy Whitson (not pictured) replaced a motor needed to move the station's solar array panels during the six-hour plus spacewalk. (Xinhua/Reuters Photo) Photo Gallery>>>

 

    Wednesday's seven-hour spacewalk was especially hazardous because of the risk of electrical shock. For safety, Whitson and Tani waited until the international space station was on the dark side of Earth, then carefully undid fasteners, disconnected cables and pulled out the old electric motor.

    A few minutes later, the spacewalkers popped in the new motor, a spare that had been stored on board. "We're all breathing down here. Thanks a lot," Mission Control said.

    Whitson and Tani performed virtually the entire job in the darkness of night, pausing during the daytime swings around Earth, when 160 volts of electricity would course through the cables. Because the motor serves as the structural backbone for the solar wing, the spacewalkers had to make sure the wing didn't come off and fly away.

    "Given the complexity of this spacewalk and the risks that we had to manage ... we are exceptionally pleased with how things went," said flight director Kwatsi Alibaruho.

    The station's power system still has problems: a joint for rotating one set of solar wings is mysteriously clogged with metal shavings and can't be fixed until later this year.

    (Agencies)