After five busy days in space and two successful spacewalks, astronauts aboard the space shuttle Discovery were supposed to take things easy on Friday.
But with a solar array halfway retracted and NASA managers willing to try all manner of creative potential fixes, the day may be busier than expected.
The solar panel was part of an interim power system the international space station was using. One of the main goals of the Discovery mission was to rewire the station and hook a new set of panels onto the permanent electricity grid.
The crew rewired half of the orbiting space lab during the first spacewalk, and is scheduled to rewire the other half in a spacewalk Saturday.
The solar panels rotate with the movement of the sun to maximize the amount of solar energy produced, but in order for the new panels to rotate, the old panel in a temporary position in the middle of the station had to be retracted.
While it was folded far enough to give clearance to the new solar panels, the old panel got stuck after retracting halfway. NASA had wanted it to retract fully.
The problem lies in a guidewire that is stuck in one of the eyelets, causing the array to billow. In tests of the array on Earth, NASA saw that issue arise, but gravity helped fix it. That's not the case in space, reports AP.
So NASA will try helping it along by jiggling the array in hopes that will push the wire through the hole. It plans to move a joint on that panel to shake it, and may also make use of an exercise device. People at the space agency noticed a panel shaking one time and later came to find out the source was astronaut Leroy Chiao working up a sweat. He had been using a bungee bar-like device to do squats and lifts and was apparently pushing it hard enough to cause a vibration. One of the three current space station crew members may be asked to repeat that workout. The space agency may also try different methods of retracting the accordion-like array using a remote control.