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Spacewalkers Replace Ammonia Pump on ISS: May 11, 2013.
Credit: NASA TV
NASA astronauts Chris Cassidy (top) and Tom Marshburn work outside the International Space Station after replacing an ammonia coolant pump on May 11, 2013.
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Spacewalks Inspect Ammonia Pump Box
Credit: NASA TV
NASA astronaut Chris Cassidy (striped spacesuit) holds an ammonia pump control box during a spacewalk to hunt for an ammonia leak outside the International Space Station on May 13, 2013. The spacesuit of astronaut Tom Marshburn can be seen behind him.
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Astronaut Shutterbug: Spacewalker Tom Marshburn
Credit: NASA TV
NASA astronaut Tom Marshburn snaps a photo of crewmate Chris Cassidy during a May 11, 2013 spacewalk in this view from Cassidy's helmet camera. The spacewalkers replaced an ammonia pump box while seeking a coolant leak outside the International Space Station.
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Spacewalkers Install New ISS Ammonia Pump
Credit: NASA TV
This view from NASA astronaut Chris Cassidy's helmet camera shows a new ammonia pump being installed during a May 11, 2013 spacewalk.
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Spacewalk at Night: May 11, 2013
Credit: NASA TV
Canadian astronaut Chris Hadfield captured this view of astroanut Chris Hadfield outside the International Space Station on May 11, 2013, during an ammonia leak-hunting spacewalk.
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Emergency Spacewalk Suit Up: May 11, 2013
Credit: NASA
NASA astronauts Chris Cassidy and Tom Marshburn don their NASA-issue Extravehicular Mobility Units for an emergency spacewalk to find an ammonia link outside the International Space Station. Canadian astronaut Chris Hadfield (center) and Russian cosmonaut Pavel Vinogradov assist in the May 11, 2013 spacewalk work.
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How ISS's Ammonia Cooling System Works (Infographic)
Credit: Karl Tate, SPACE.com Infographics Artist
The ammonia system is one of several cooling loops that circulate liquids throughout the International Space Station.
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Emergency Spacewalk Astronauts: May 11, 2013
Credit: NASA
NASA astronaut Chris Cassidy and Tom Marshburn will perform an emergency spacewalk outside the International Space Station on May 11, 2013, to identify and perhaps fix an ammonia coolant leak.
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Emergency Spacewalk Worksite: May 11, 2013
Credit: NASA
This NASA graphic shows the location of the ammonia leak on the International Space Station to be inspected by astronauts in an emergency spacewalk on May 11, 2013.
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Emergency Spacewalk Astronaut Path: May 11, 2013
Credit: NASA
This NASA graphic shows the path astronauts Tom Marshburn and Chris Cassidy will take to reach an ammonia leak outside the International Space Station in an emergency spacewalk on May 11, 2013.
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Mission Management Team Discusses Station Ammonia Leak
Credit: NASA
On May 10, 2013, members of the International Mission Management Team convene for a session in the Christopher C. Kraft Mission Control Center to discuss the status of a recently discovered ammonia leak on the International Space Station and the likelihood of a space walk over the coming weekend. The extravehicular activity would likely be performed by two Expedition 35 crew members to resolve the issue.
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Ammonia Pump Control Box: Detailed View
Credit: NASA
This NASA graphic provides a detailed look at the ammonia pump control box to be inspected and possibly replaced during an emergency spacewalk on May 11, 2013.
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ISS Ammonia Pump Flow Control Subassembly
Credit: NASA
This NASA images shows the type of liquid ammonia pump control box to be inspected during an emergency spacewalk outside the International Space Station on May 11, 2013.
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Ammonia Pump Flow Control Subassembly (Back View)
Credit: NASA
A rear view of the type of liquid ammonia pump control box to be inspected during an emergency spacewalk outside the International Space Station on May 11, 2013.
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Space Station P6 Coolant Loop Explained
Credit: NASA
This NASA graphic explains the components of the solar array cooling system on the International Space Station's Port 6 truss.
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Astronauts Evaluate Ammonia Spacewalk Procedures
Credit: NASA
On May 10, 2013, NASA astronaut Terry Virts simulates extravehicular activity in the Johnson Space Center's Neutral Buoyancy Laboratory. His session, in which he was joined by European Space Agency astronaut Samantha Cristoforetti (background), was to evaluate proper procedures and techniques in support of a possible weekend space walk by two astronauts on the International Space Station to trouble-shoot an ammonia leak issue, discovered earlier in the week. A number of SCUBA-equipped divers were in the water to assist the astronauts.
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Space Station Solar Array Cooling System
Credit: NASA
This NASA graphic shows the locations of hardware on the International Space Station's Port 6 Truss, where the cooling system for the 2B solar array panels, and the solar array itself, are located.
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Astronauts Evaluate Ammonia Spacewalk Procedures
Credit: NASA
On May 10, 2013, NASA astronaut Terry Virts simulates extravehicular activity in the Johnson Space Center's Neutral Buoyancy Laboratory. His session, in which he was joined by European Space Agency astronaut Samantha Cristoforetti (out of frame), was to evaluate proper procedures and techniques in support of a possible weekend space walk by two astronauts on the International Space Station to trouble-shoot an ammonia leak issue, discovered earlier in the week. A number of SCUBA-equipped divers were in the water to assist the astronauts.
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Astronauts Submerging in Waters of Neutral Buoyancy Laboratory
Credit: NASA
On May 10, 2013, European Space Agency astronaut Samantha Cristoforetti, in a ground version of the NASA extravehicular mobility unit space suit, is about to go under the water in the Johnson Space Center's Neutral Buoyancy Laboratory. Her session, in which she was joined by NASA astronaut Terry Virts (out of frame), was to evaluate proper procedures and techniques in support of a possible weekend space walk by two astronauts on the International Space Station to trouble-shoot an ammonia leak issue, discovered earlier in the week. A SCUBA-equipped diver is in the water to assist the astronauts.
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Astronauts Evaluate Ammonia Spacewalk Procedures
Credit: NASA
On May 10, 2013, NASA astronaut Terry Virts simulates extravehicular activity in the Johnson Space Center's Neutral Buoyancy Laboratory. His session, in which he was joined by European Space Agency astronaut Samantha Cristoforetti (out of frame), was to evaluate proper procedures and techniques in support of a possible weekend space walk by two astronauts on the International Space Station to trouble-shoot an ammonia leak issue, discovered earlier in the week. A number of SCUBA-equipped divers were in the water to assist the astronauts.
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Astronauts Submerging in Waters of Neutral Buoyancy Laboratory
Credit: NASA
On May 10, 2013, European Space Agency astronaut Samantha Cristoforetti prepares to be submerged in the waters of the Johnson Space Center's Neutral Buoyancy Laboratory. Her session, in which she was joined by NASA astronaut Terry Virts (partially visible behind Cristoforetti), was to evaluate proper procedures and techniques in support of a possible weekend space walk by two astronauts on the International Space Station to trouble-shoot an ammonia leak issue, discovered earlier in the week. A SCUBA-equipped diver is in the water to assist the astronauts.
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Astronauts Prep for Spacewalk Testing in Neutral Buoyancy Lab
Credit: NASA
On May 10, 2013, wearing the thermal undergarments for their extravehicular mobility unit space suits, NASA astronaut Terry Virts and European Space Agency astronaut Samantha Cristoforetti confer with space walk expert Allissa Battocletti about procedures and techniques they would later rehearse in the waters of the Johnson Space Center's Neutral Buoyancy Laboratory (visible through the window on the floor below). The ground based rehearsal was in support of a possible weekend space walk to be performed by two NASA astronauts aboard the International Space Station as they attempt to trouble-shoot an ammonia leak issue, discovered earlier in the week.
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Astronauts Prep for Spacewalk Testing in Neutral Buoyancy Lab
Credit: NASA
On May 10, 2013, wearing the thermal undergarments for their extravehicular mobility unit space suits, NASA astronaut Terry Virts and European Space Agency astronaut Samantha Cristoforetti confer with space walk experts and trainers (out of frame) about procedures and techniques they would later rehearse in the waters of the Johnson Space Center's Neutral Buoyancy Laboratory (out of frame on the floor below). The ground based rehearsal was in support of a possible weekend space walk to be performed by two NASA astronauts aboard the International Space Station as they attempt to trouble-shoot an ammonia leak issue, discovered earlier in the week.
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Astronauts Prep for Spacewalk Testing in Neutral Buoyancy Lab
Credit: NASA
On May 10, 2013, wearing the thermal undergarments for their extravehicular mobility unit space suits, NASA astronaut Terry Virts and European Space Agency astronaut Samantha Cristoforetti go over an agenda of procedures and techniques they would later rehearse in the waters of the Johnson Space Center's Neutral Buoyancy Laboratory (out of frame on the floor below). The ground based rehearsal was in support of a possible weekend space walk to be performed by two NASA astronauts aboard the International Space Station as they attempt to trouble-shoot an ammonia leak issue, discovered earlier in the week.
