CAPE CANAVERAL, Fla. (AP) - Astronauts are trying to make an urgent and complicated repair outside the International Space Station. The six-man crew had to turn off all nonessential equipment inside the orbiting lab 10 days ago after an ammonia pump malfunctioned.
The pump replacement is a huge undertaking attempted only once before, in 2010. NASA has ordered up three spacewalks to complete the job. The next one will be Monday.
American Astronauts Rick Mastracchio (muh-STRAK'-ee-oh) and Michael Hopkins will go back out again Christmas Day, if any work remains.
The six-man crew had to turn off all nonessential equipment inside the orbiting lab following the malfunction on Dec. 11. Scientific research came to a near-halt.