NASA Begins Series of Spacewalks to Fix Coolant Pump on ISS
Expedition 38 astronauts Rick Mastracchio and Mike Hopkins ventured outside the space station on Dec. 21, for the first in a series of spacewalks to remove and replace a faulty coolant pump module. The pump is associated with one of the station’s two external cooling loops, which circulate ammonia outside the station to keep both internal and external equipment cool.
The previously planned mission of Orbital Sciences’ Cygnus spacecraft has been moved to no earlier than mid-January. The postponement will allow ample time for the station crew to focus on repairing the pump module, which stopped working properly on Dec. 11.