In this image taken from video provided by NASA, astronauts Rick Mastracchio, top, and Michael Hopkins work to repair an external cooling line on the International Space Station on Monday, Dec. 24, ... more 
In this image taken from video provided by NASA, astronauts Rick Mastracchio, top, and Michael Hopkins work to repair an external cooling line on the International Space Station on Monday, Dec. 24, 2013, 260 miles above Earth. The external cooling line one of two shut down Dec. 11. The six-man crew had to turn off all nonessential equipment, including experiments. (AP Photo/NASA) less 
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Associated Press | Photo By AP Photo/NASA
Tue, Dec 24, 2013 11:00 AM EST