Monthly Archives: May 2013

MIAMI (Reuters) - NASA plans to send two astronauts aboard the International Space Station out on a spacewalk on Saturday to try to fix an ammonia leak in a cooling system on one of the station's solar arrays, the U.S. space agency said on Friday.

The crew spotted a steady stream of small, white frozen ammonia flakes floating away from a coolant line outside the orbital outpost on Thursday.

Mission managers reviewed images and data gathered overnight and said on Friday they tentatively planned to send American astronauts Chris Cassidy and Tom Marshburn out on Saturday morning to try to stop the leak by replacing a pump on the cooling system.

"The crew is not in danger, and the station continues to operate normally otherwise," NASA said in a news release.

Ammonia is used to cool the power systems that operate the solar arrays, which provide electricity to the station. Each of the eight solar arrays has its own independent cooling system.

The leak is on the far left side of the station's truss structure, in an ammonia loop that astronauts previously tried to troubleshoot during a spacewalk in November 2012.

While Cassidy and Marshburn are working outside the space station, crew commander Chris Hadfield, a Canadian astronaut, will choreograph their movements from inside the orbital outpost. Russian cosmonauts Pavel Vinogradov, Alexander Misurkin and Roman Romanenko make up the rest of the crew.

Work was under way to reroute the remaining power channels to maintain full operation of the systems normally controlled by the solar array that is cooled by the leaking loop.

The space station, a $100 billion research laboratory that orbits 250 miles above Earth, is owned by the United States and Russia in partnership with Europe, Japan and Canada.

(Reporting by Jane Sutton; Editing by Vicki Allen and Philip Barbara)

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Spacewalk planned to fix ammonia leak on space station

Astronauts on the International Space Station are gearing up to perform a potential emergency spacewalk Saturday (May 11) to hunt for an ammonia leak in the orbiting laboratory's cooling system.

NASA astronauts Tom Marshburn and Chris Cassidy are planning to spend more than six hours outside the station to find, and possibly repair, the ammonia coolant leak.

The spacewalk will come two days after the six-man crew of the space station noticed frozen flakes from an ammonia leak on one of the eight wing-like solar arrays responsible for supplying power to the station. Planning a space station spacewalk repair in such a fast timeframe is unprecedented, NASA officials said. [How the Space Station's Cooling System Works (Infographic)]

It also comes just two days before Marshburn and two crewmates, station commander Chris Hadfield of Canada and Russian cosmonaut Roman Romanenko, are due to return home on Monday, May 13. The departures and arrivals of the crewmembers will not be affected by the spacewalk, NASA officials said.

The space station crew is in no danger, and the pump has been turned off in order to slow the rate of leaking coolant, mission managers said. The leak is on the space station's Port 6 truss, at the leftmost side of the outpost's football field-length main truss.

"[The] objective is to get a look at the leak," Mike Suffredini, NASA's International Space Station program manager said of the spacewalk during a briefing today.

Spacewalk repair on tap

A team of NASA officials will meet later tonight to make an final decision whether to proceed with the spacewalk. If approved, the excursion will begin early Saturday at 7:15 a.m. EDT (1115 GMT).

The spacewalk will air live on NASA TV beginning at 7 a.m. EDT (1100 GMT). You can watch the webcast live on SPACE.com, courtesy of NASA.

If the spacewalk does go forward, Cassidy and Marshburn will float outside of the station to inspect the leaking loop. The two astronauts will then attempt to replace an ammonia coolant pump that station engineers suspect may be the location of the leak, NASA officials said.

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Astronauts Set for Emergency Spacewalk to Fix Space Station Leak

On Saturday NASA will try to fix the leak that released a stream of white frozen flakes into space. The crew on the International Space Station is not in danger and the space station is continuing to operate normally. NBC's Brian Williams reports.

By Miriam Kramer Space.com

Astronauts on the International Space Station are gearing up to perform an emergency spacewalk Saturday to hunt for an ammonia leak in the orbiting laboratory's cooling system.

NASA astronauts Tom Marshburn and Chris Cassidy are planning to spend more than six hours outside the station to find, and possibly repair, the ammonia coolant leak.

The spacewalk comes just two days after the six-man crew of the space station noticed frozen flakes from an ammonia leak on one of the eight winglike solar arrays responsible for supplying power to the station. Planning a space station spacewalk repair in such a short time frame is unprecedented, NASA officials said. [Infographic: How the Space Station's Cooling System Works]

It also comes just two days before Marshburn and two crewmates, station commander Chris Hadfield of Canada and Russian cosmonaut Roman Romanenko, are due to return home. Monday's departure will not be affected by the spacewalk, NASA officials said.

The space station crew is in no danger, and the pump has been turned off in order to slow the rate of the leak, mission managers said. The leak is on the space station's P6 truss, at the leftmost side of the outpost's football field-length main truss.

NASA's space station program manager, Mike Suffredini, said the spacewalk's "objective is to get a look at the leak."

Spacewalk repair on tap A team of NASA officials gave the go-ahead late Friday for the spacewalk to begin at 8:15 a.m. ET Saturday. The plan calls for Cassidy and Marshburn to float outside of the station to inspect the leaking loop. Then they'll try to replace an ammonia coolant pump that station engineers suspect may be the source of the leak.

Marshburn and Cassidy have both conducted three spacewalks two of them together during their 2009 mission on the space shuttle Endeavour. This spacewalk is expected to take a little more than six hours. "The crew is very familiar in this area," Norm Knight, NASA chief flight director, said during a briefing on Friday. This type of repair, however, is unprecedented in the space station's history, he added.

Read more from the original source:
Spacewalkers set to troubleshoot space station's ammonia coolant leak