Photos: Astronauts Spacewalk to Fix Vital Space Station Cooling System

Rick Mastracchio Moves at Sunrise

NASA TV

NASA astronaut Rick Mastracchio moves toward the International Space Station's robotic arm as the station moves into daylight on Dec. 24, 2013.

Mike Hopkins on Space Station's Robotic Arm

NASA TV

NASA astronaut Mike Hopkins prepares to attach himself to the International Space Station's robotic arm during a Christmas Eve spacewalk on Dec. 24, 2013.

Astronaut Mike Hopkins Outside International Space Station

NASA TV

NASA astronaut Mike Hopkins floats outside the International Space Station on Dec. 24, 2013.

Astronaut Mike Hopkins on 1st Spacewalk

NASA/Mike Hopkins (@AstroIllini)

NASA astronaut Mike Hopkins looks to the camera during his first spacewalk on Dec. 21, 2013.

Rick Mastracchio on Robotic Arm

NASA TV

Astronaut Rick Mastracchio holds the failed pump module during a spacewalk Dec. 21.

Mike Hopkins Builds Spacesuit

Mike Hopkins (via Twitter as @ AstroIllini)

Astronaut Mike Hopkins tweeted this photo while aboard the International Space Station. “Built a space suit yesterday with @AstroRM. Pretty cool day,” he said on Dec. 19, 2013.

Astronauts Remove Pump from Space Station

NASA TV

Astronauts Mike Hopkins and Rick Mastracchio pull a faulty pump module out of the International Space Station's vital cooling system.

Rick Mastracchio on Robotic Arm

NASA TV

NASA astronaut Rick Mastracchio stands on the International Space Station's robotic arm during an urgent spacewalk to fix the station's vital cooling system.

Rick Mastracchio Removes Degraded Ammonia Pump

NASA TV

Flight Engineer Rick Mastracchio works outside the International Space Station during Saturday's spacewalk to remove a degraded ammonia pump. This image was released Dec. 23, 2013.

Astronauts Spacewalk Outside Space Station

NASA TV

Astronauts Mike Hopkins and Rick Mastracchio on the outside of the International Space Station on a spacewalk to begin repairs on the station's vital cooling system on Dec. 21.

Astronauts Spacewalk Outside Space Station

NASA TV

Astronauts Mike Hopkins and Rick Mastracchio ventured outside of the International Space Station to begin repairs on the station's vital cooling system on Dec. 21.

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