CAPE CANAVERAL, Fla. — Discovery’s astronauts took one final spacewalk at the International Space Station yesterday to get the outpost squared away before the shuttle program ends.
Discovery is headed into retirement after this flight, and only two more shuttle trips remain, by Endeavour and then Atlantis.
Spacewalker Alvin Drew quickly headed to a broken pump and drained the last bit of ammonia left to make it safe for handling in case it’s returned to Earth on the last shuttle mission this summer.
The toxic ammonia coolant — about 10 pounds’ worth — was vented through a hose out to open space, away from the two spacewalkers.
It took two minutes to empty the pump.
A few pieces of frozen ammonia appeared to float away. Mission Control asked if spacewalker Stephen Bowen encountered any of the bits of ice, and he replied that he had not. Controllers wanted to keep any ammonia residue from getting into the space station.
Discovery will remain at the space station until Sunday. The shuttle astronauts are staying an extra day to help outfit the new storage room installed Tuesday.