Astronauts aboard the International Space Station prepared today for a spacewalk to store an extension boom and other tasks, the fifth and final outing during a busy visit by the shuttle Endeavour.
The extension sensor-studded boom was used on Friday to scan Endeavour's heat shield to ensure it is safe for next week's re-entry through the Earth's atmosphere.
The scan, part of the safety enhancements NASA implemented after shuttle Columbia's fatal flight in 2003, is usually done after the spacecraft undocks from the station. But the next shuttle mission will have such a crowded payload that there will be no room for the boom, so it must be stored on the space station.
The complex storage procedure will be done in stages.
"This is very complicated," lead shuttle flight director Mike Moses said late on Friday at a mission status briefing at the Johnson Space Center in Houston.
Moses said it would be 24 to 36 hours before the data from Friday's scan was fully assessed. Initial observations suggested no damage, but he said those visual scans can fail to detect problems.
"It is very easy to get a false sense of security from the visuals," he said.
During today's spacewalk astronauts Robert Behnken and Mike Foreman will also inspect a contaminated joint that is needed to rotate one of the station's solar wing panels.