Expedition 38 crew member Mike Hopkins checks out the spacesuit he will be wearing on a spacewalk in the International Space Station, in this undated handout photo from NASA. Hopkins and fellow ... more 
Expedition 38 crew member Mike Hopkins checks out the spacesuit he will be wearing on a spacewalk in the International Space Station, in this undated handout photo from NASA. Hopkins and fellow astronaut Rick Mastracchio will conduct a series of spacewalks beginning Saturday to replace an ammonia pump that is part of the station's coolant system. This will be Hopkins' first spacewalk, while Mastracchio has had six previous ones on STS-118 and STS-131. REUTERS/NASA/Handout (OUTER SPACE - Tags: SCIENCE TECHNOLOGY) ATTENTION EDITORS - THIS IMAGE WAS PROVIDED BY A THIRD PARTY. FOR EDITORIAL USE ONLY. NOT FOR SALE FOR MARKETING OR ADVERTISING CAMPAIGNS. THIS PICTURE IS DISTRIBUTED EXACTLY AS RECEIVED BY REUTERS, AS A SERVICE TO CLIENTS less 
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Reuters | Photo By NASA / Reuters
Fri, Dec 20, 2013 12:31 PM EST