NASA unfurled the first of two golden solar wings on the new 17½-ton addition to the international space station early Thursday after overcoming a software problem that delayed the maneuver for hours.
As they opened separately like accordion window blinds, the solar wings looked like cosmic blankets of gold bars in the reflection of an orbital sunrise.
"Big day for space station. Congratulations," astronaut Pam Melroy in Mission Control radioed Atlantis commander Brent Jett. "We're all extremely happy."
The astronauts had adjusted the space station's position before starting, then halted each deployment midway for about 30 minutes so the solar panels could be heated by the sun to prevent them from sticking together, a problem astronauts have encountered before.
NASA engineers ran into one early glitch with the space station's new ferris-wheel-like rotating joint that allows the solar arrays to move with the sun to maximize the amount of power generated.
They were able to fix the software problem, but it put the day's activities several hours behind schedule.
Space shuttle Atlantis' 11-day schedule is tightly packed, and the arrays needed to be deployed in order for astronauts to go on the third and final spacewalk of the mission Friday.
The mission is the first since late 2002 to resume space-station construction, which was halted after the Columbia accident in early 2003.
"About the only thing on the timeline that's accurate at this point is probably the postsleep," astronaut Kevin Ford in Mission Control in Houston told space station astronaut Jeff Williams, referring to the time after the crew wakes up devoted to personal hygiene.
"Nothing like adding a little drama to the day," Williams said a short time later.
The solar arrays were mounted on blankets and folded up like an accordion for delivery to space as part of the new $372 million addition added to the space station. Together, they span 240 feet.
When the space station is completed in 2010, the solar arrays will provide about a quarter of its power.
Two of Atlantis' astronauts are experienced in deploying solar arrays. Atlantis commander Jett and mission specialist Joe Tanner were members of a crew in 2000 that also delivered a pair of solar wings to the space station.
During that mission, the solar panels unexpectedly stuck to each other while they were being deployed, but the problem was fixed.
This time around, NASA devised a new method for unfurling the solar wings which allowed them to be heated up by the sun.