Shuttle Astronauts Power Up Space Station’s Robot Arm

For the second time this week, two space shuttle astronauts floated outside Tuesday and hooked up cables that sent power coursing through the international space station’s new 58-foot robot arm.

To NASA’s relief, Endeavour spacewalkers Scott Parazynski and Chris Hadfield managed to get both power lines working, after slaving over cable connections.

“Hip, hip, hooray!” the spacewalkers cheered when the backup power line came to life. Applause filled the room at Mission Control.

Only one power routing is needed to operate the robot arm, a billion-dollar, two-handed construction crane that is needed to finish building the space station. But NASA wanted both lines up and running in case one failed.

That wasn’t the only problem during the spacewalk, which lasted 7 1/2 hours, an hour longer than planned.

A connector came apart after Hadfield removed an old radio antenna from the space station, and the cap floated into a berthing port. He could not reach the piece. “If only there was someone out here with long arms,” he said.

Later, the petals of the port were opened one by one, in hopes the cap would float out. “Like a lot of things in zero-g, it’s drifted off into some inaccessible corner and won’t come out until it’s ready,” Hadfield reported.

NASA officials said the metal cap--about the size of a stack of seven quarters--could interfere when the next space station piece is attached to that berthing port in two months. “There are going to be a lot of discussions about that in the coming days, because it is a concern,” said John Curry, the lead station flight director.

Hadfield also had trouble removing a video signal converter from the packing cradle for the robot arm. He turned the release bolt 26 times, 15 times more than he was supposed to, and still the converter would not come off. He had to give up on that too.

During a spacewalk Sunday, Parazynski and Hadfield installed the robot arm on a temporary mount on space station Alpha. One of the arm’s hands let go of that mount Monday and reached over and clamped down on a power and control socket 24 feet away, its base for the next year. The spacewalkers connected four cables at the socket Tuesday, to provide not only power to the arm but computer data and video.

Despite all the spacewalking action, Parazynski and Hadfield found time to admire the sights 240 miles below. They were oohing and aahing at lightning over Southeast Asia when crew mate John Phillips urged them to get back to work. They did.