Astronauts progress in mission
Spacewalking astronauts had to rely on brute force to remove a broken coolant pump that hampered operations at the International Space Station.
Their first attempt at emergency repairs to the cooling system was thwarted last weekend by a large ammonia leak.
This time there was no burst of toxic ammonia from a stubborn connector, just a few frozen flakes that drifted harmlessly away.
"That's great news," astronaut Douglas Wheelock reported.
"That's awesome news," Mission Control agreed.
The urgent repair job - now expected to require two more spacewalks - is considered one of the most challenging in the 12-year history of the space station.
The cooling system is crucial for keeping electronics from overheating, and half of the system was knocked out when the ammonia pump failed 1 1/2 weeks ago.
Science research is on hold and unnecessary equipment is off until the pump can be replaced. Engineers suspect an electrical short in the pump led to the shutdown.