NASA Completes Space Station Repair, Successfully Fixes Cooling System

Doug Wheelock and fellow astronaut Tracy Caldwell Dyson completed the second of three spacewalks to remove a failed ammonia coolant pump module on the station's S1 truss on Wednesday, Aug. 11. Courtesy of NASA

On Monday, NASA astronauts completed their last spacewalk of a three-part mission to repair the International Space Station, successfully replacing a malfunctioning pump in the station’s cooling system.

On July 31, one of the pumps in the station’s cooling system shorted out, forcing the crew on board to shut down equipment to prevent overheating.

Then, on August 7, NASA astronauts Wheelock and Tracy Caldwell Dyson went out on an eight-hour spacewalk to fix the pump, but could not complete their repairs due to an ammonia leak.

What didn’t work then did work four days later. On August 11, Wheelock and Dyson successfully removed the malfunctioning coolant pump in a seven-hour, 26 minute spacewalk.

On Monday, Wheelock and Dyson completed the fix with the installation of a new 780-pound pump module. The astronauts first removed the pump from “an external stowage platform.” Then, “Wheelock attached four bolts and Caldwell Dyson mated five electrical connectors,” successfully installing the module onto the station’s starboard, reported NASA.

The spacewalk on Monday lasted 7 hours and 20 minutes. The module was confirmed to be working properly when power was connected.

Space.com reported that a fourth spacewalk is needed to do some final clean-up work, but according to mission managers, it is not an urgent matter.