CAPE CANAVERAL, Fla. - Spacewalking astronauts wired up the International Space Station's new $600 million electric tower Tuesday, routing a crucial stream of direct current from its newly sprouted solar wings to the power-hungry outpost.

Working nine stories above their shuttle mothership, the orbital electricians also used helmet-cams to pinpoint a problem with one of the massive arrays, which are the largest, most powerful and most expensive ever erected in space.

Endeavour astronaut Carlos Noriega works outside the International Space Station complex on Tuesday during the second planned spacewalk of shuttle mission STS-97 in this image from NASA TV.

As ground engineers suspected, razor-thin cables designed to tighten one of the wing's blue-and-gold blankets jumped off their pulleys, leaving the huge solar panel a bit slack after it was unfurled in orbit Sunday.

Endeavour spacewalkers Joe Tanner and Carlos Noriega likely will scale the power tower and try to pull the cables taut during a spacewalk slated to start at 11:51 a.m. Eastern Standard Time (16:51 GMT) Thursday.

"We think we've got, hopefully, a pretty good handle on it and can probably fix it," astronaut Jerry Ross told the spacewalkers from NASA's Mission Control Center in Houston.

"Great!" Noriega replied.

The lofty cable inspection work came amid a six-hour, 37-minute excursion mainly aimed at hooking up electrical lines that now link the 17-ton power tower with the international outpost.

Dressed up in $12 million spacesuits, Tanner and Noriega sauntered through the challenging construction work, which was deemed essential to quintupling the amount of electricity available to run critical station systems.

"You guys are doing an awesome job," said Canadian astronaut Marc Garneau, who directed the intricately orchestrated spacewalk from a window inside shuttle Endeavour's crew cabin.

"Flattery will get you everywhere, you know," Tanner replied.

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Stretching 240 feet (73 meters) from tip to tip, the high-voltage solar wings are capable of generating a staggering 64 kilowatts of direct current (DC) power -- or enough electricity to run 30 average American homes without air conditioning.

Station flight controllers set out late Tuesday to send electricity from the wings through power converters and into the station.

Endeavour astronaut Joe Tanner works outside the International Space Station complex on Tuesday during the second planned spacewalk of shuttle mission STS-97 in this image from NASA TV.

The wiring work paved the way to the much-anticipated opening of the $300 million U.S. Unity module, one of three pressurized working areas that now make up the station.

The outpost's first full-time tenants have made quick sorties into the module, but Unity otherwise has remained off limits because power supplies were too meager to heat it.

Consequently, U.S. astronaut Bill Shepherd and two colleagues -- cosmonauts Yuri Gidzenko and Sergei Krikalev -- have been cooped up in station crew quarters and a cluttered Russian space tug since they took up residence at the outpost Nov. 2.

"We'll get you in (Unity) permanently (Wednesday)," astronaut Joan Higginbotham told Shepherd before the latter headed off for a celebratory dinner with his station mates.

"Bon appetit," she added.

The extra power also is key to expanding the growing station.

The planned mid-January launch of the U.S. Destiny lab -- which will be the scientific heart of the station -- hinged on the successful completion of the wiring work.

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NASA and its 15 international partners, meanwhile, now expect to have enough power to support the $60 billion station construction project until December 2002, when the next set of U.S. solar arrays is to be delivered to the outpost.

Ultimately, four sets of American-made solar wings and a Russian power tower will be needed to juice the station, which eventually will weigh 480 tons and span an area as big as two football fields set side by side.

Mission Endeavour

Look here for the latest news from NASA's STS-97.

The wiring work wasn't all the spacewalkers accomplished.

Scaling the station like rock climbers, Tanner and Noriega moved a key radio antenna from a stowage spot on the side of a girder-like station truss to the top of the new power tower.

Perched on the end of the shuttle's 50-foot (15-meter) robot arm, Tanner hauled the lengthy antenna up the side of the station, holding it out away from the outpost to make certain he didn't bump the sensitive communications boom.

"You look like the Statue of Liberty right now," Garneau told his crewmate.

"Gosh, this is great," Tanner said.

With the robot arm stretched out as far as it could go, Tanner then handed the dish-shaped antenna and its boom off to Noriega before inch worming up above his spacewalking partner.

Ultimately, Noriega passed the antenna back to Tanner so he could mount it atop the power tower and then swing the boom out away from the station.

"Sure is pretty, isn't it," Tanner said.

"Oh yeah," Noreiga replied.

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The astronauts also had time to hook up coolant lines and work on radiators designed to shed heat generated by the station's new electrical system. And they prepared a shuttle docking port for a move that will take place when the Destiny lab is delivered early next year.

Expedition One

Look here for the latest news about the first crew to live and work aboard the International Space Station.

A visiting construction crew, making way for the arrival of the station's first science lab, will temporarily relocate the conical docking port. It then will be repositioned at the end of the lab, where it will serve as a space shuttle parking place.

The spacewalk was the second of three planned for Endeavour's mission. Tanner and Noriega will be at it again Thursday, setting up a device that will gauge whether the new solar wings create a shock hazard to astronauts working outside the station.

Mission managers will decide Wednesday whether to send the astronauts to work on the slack solar wing blanket during that third and final foray.

The shuttle and station crews, meanwhile, plan to meet inside the outpost about 9:30 a.m. EST (14:30 GMT) Friday.

The Endeavour astronauts will deliver Christmas presents, fresh fruit and a small load of supplies to the station tenants.

The two crews will bid adieu Saturday as the shuttle pulls away from the station and heads off on a two-day trip back to Earth. Endeavour and its astronauts remain scheduled to land at Kennedy Space Center at 6:19 p.m. EST (23:19 GMT) Dec. 11.