Stunning footage of the critical construction work will be captured by shuttle cameras and new helmet-mounted cameras on the spacewalkers and broadcast live on SPACE.com during a spacewalk scheduled to begin about 1:30 p.m. Eastern Standard Time (18:30 GMT) Sunday.

"I think the view is going to be just absolutely fantastic," Endeavour spacewalker Joe Tanner told SPACE.com before the shuttle blasted off for the station.

"These things are huge. They're quite colorful," he said. "And once those arrays are out, the station will be the third brightest 'star' in the heavens."

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Designed to unfold like a huge accordion in orbit, the shimmering gold-and-blue arrays are crucial to augmenting meager power supplies at the station, which are so limited that one of the outpost's three pressurized working areas remains off limits to its resident crew.

What's more, the giant panels must be successfully deployed in order for NASA and its 15 international partners to continue building new additions onto the power-hungry station.

Project officials, consequently, will be keeping close tabs as events unfold in orbit, hoping some sort of drastic hitch doesn't force the astronauts to jettison the huge arrays.

"If something jams and the astronauts can't override it, then they've got to get rid of them," said NASA payload manager David Flowers.

"We'll be a little bit nervous," Nanette Bouchard, a senior station project manager with The Boeing Co., acknowledged. "We'll all hold our breath a little bit."

The high drama on the high frontier will come a day after a flawless shuttle rendezvous and docking at the 13-story outpost, which now is occupied by U.S. astronaut Bill Shepherd and two Russian cosmonauts, Yuri Gidzenko and Sergei Krikalev.

With shuttle skipper Brent Jett at the controls, Endeavour eased its way up to the station from behind and below at 3 p.m. EST (20:00 GMT) Saturday, parking at a new docking port added to the outpost by a visiting construction crew in October.

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Coupled together by identical, Russian-made docking rings, the joined spacecraft now stretch 220 feet (67 meters) in length and weigh about 213 tons.

The station's first inhabitants -- who arrived at the outpost in early November -- had a front row seat for the link-up, which took place as Endeavour and Alpha flew in formation some 235 miles (376 kilometers) above Kazakhstan.

Space Station Alpha as it appeared to Endeavour's crew in the minutes before docking today.

"Alpha, Endeavour," Jett radioed to station commander Shepherd -- a U.S. Navy colleague -- as he prepared to make a final, glacial approach to the outpost. "Endeavour is station-keeping at 30 feet, requesting permission to come alongside and dock."

"Endeavour, Alpha," Shepherd replied. "You're clear to board."

"That was an awesome rendezvous and approach and docking," NASA astronaut Shannon Lucid added from the agency's mission control center in Houston.

Canadian astronaut Marc Garneau then set out to raise the 17-ton power tower from a cargo bay cradle with the shuttle's 50-foot (15-meter) robot arm, which also will be used to mount the girder-like truss to the top of the station Sunday.

The so-called P6 Integrated Truss houses the giant arrays, which are folded up in solar blanket boxes; the mast upon which they will be deployed; associated batteries and electronics; and three radiators to dispel excess heat built up during the generation of electricity.

The entire package is the largest and heaviest element delivered to the station by a shuttle. The astronauts planned to leave it hovering above the shuttle's cargo bay Saturday night and early Sunday to keep it at the right temperature for its attachment to the outpost.

The spacewalk Sunday will be the first of three during the shuttle's visit to the station.

Tanner and shuttle crewmate Carlos Noriega plan to wire the arrays to the station and reposition a key communications antenna during a second excursion scheduled to begin about 1 p.m. EST (18:00 GMT) Tuesday.

A third spacewalking foray will be staged just after noon EST (17:00 GMT) Thursday to mount a device designed to determine whether electrostatic discharge from the solar wings might create a shock hazard to astronauts working outside the station.

Both of those spacewalks also will be broadcast live on SPACE.com.

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The shuttle and station crews, meanwhile, won't actually meet face to face until after the final spacewalk. Hatches between the craft will be closed until then to keep the atmospheric pressure within the shuttle lower than that aboard the station.

Expedition One

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

The lower pressure enables astronauts to spend less time - 45 minutes rather than four hours - breathing pure oxygen before a spacewalk, an act crucial to avoiding dangerous bouts of decompression sickness, which scuba divers call "the bends."

As it stands, the Alpha and Endeavour crews will join together for a welcoming ceremony aboard the station about 9:30 a.m. EST (14:30 GMT) Dec. 8. Christmas presents, fresh fruit and a small load of station supplies will be delivered to Shepherd, Gidzenko and Krikalev.

The two crews will bid adieu the following day as the shuttle pulls away from the station and heads off on a two-day trip back to Earth.

Endeavour and its crew - which also includes pilot Mike Bloomfield - are scheduled to land at Kennedy Space Center at 6:19 p.m. EST (23:19 GMT) Dec. 11.