US astronauts have ended their second spacewalk, folding up old solar panels on the International Space Station.
US astronauts on Monday connected the ISS's new solar panels
The two shuttle Atlantis astronauts folded a solar wing to allow a new system of panels to rotate properly.
They should complete the work in the next walk on Thursday and a fourth walk on Friday will see if repairs are needed to the thermal re-entry blanket.
Damage to the shuttle Columbia in 2003 during its launch led to the vehicle's disintegration as it returned to Earth.
All seven crew died.
Engineers do not think the damaged section this time will endanger the re-entry.
They think the blanket was loosened by aerodynamic forces and was not hit by debris.
The second spacewalk began at 1828 GMT on Wednesday, Nasa said.
Pat Forrester and Steve Swanson spent more than seven hours on the old and new solar arrays before fellow astronaut James Reilly told them: "We're going to call it quits on this part of your job for today. Excellent job."
Atlantis docked with the International Space Station on Sunday.