The International Space Station has spread a new pair of golden wings. They are solar panels that will double the amount of power available to the outpost. Unfurling them took longer than expected because of a computer software problem.
The successful deployment of the solar arrays completes the main task of the current visit of the U.S. shuttle Atlantis to the International Space Station. They are the first new hardware on the outpost since the shuttle Columbia accident in 2003 halted construction missions.
Space station manager Mike Suffredini says he is ecstatic after the solar panel rollout.
"This flight has gone better than my wildest dreams anyway. We're well on our way to returning to assembly," he said.
The solar energy panels came up on Atlantis attached to a 17-ton girder, which spacewalking astronauts spent two days this week attaching to the orbiting research outpost.
Before they were spread, the thin mylar plastic panels were collapsed in accordion folds. The rollout was delayed three hours because flight controllers had difficulty with computer software that commands the solar arrays to swivel and follow the sun.
When they overcame that problem, the Atlantis crew started the machinery that slowly unfurled them to their full length of nearly 80 meters. According to the plan, the panels were first warmed in the sun, then expanded only half way to allow them to bask in the sun 30 minutes more before the final extension. Mission planners wanted the heat to prevent the mylar from sticking together and creating unnecessary tension on the thin material, as occurred with the first pair of solar panels in 2000.
Mike Suffredini praised the shuttle flight and ground crews for their performance on this mission.
"These guys made it look really easy, and this was a very, very difficult flight. So I guess I've got to say I couldn't ask for a better restart to assembly," he said.
The solar panels are the second of four planned arrays that will support more research laboratories, living quarters, and other equipment to be added to the space station before the shuttle fleet is retired in 2010. U.S. mission control has confirmed that they are working.
Two Atlantis astronauts will conduct the third and final spacewalk of the mission Friday to continue preparing the arrays for operation. They will also perform other maintenance chores, such as changing a space station antenna that has deteriorated in the harsh space environment and installing a heat shield over another antenna.
The shuttle is scheduled to undock from the space station Sunday and land on Earth Wednesday. In between, the next space station crew arrives on a Russian Soyuz rocket to begin their six-month tour of duty.