ISS: two astronauts into space to repair the ammonia leak - Update

Two U.S. astronauts on the International Space Station (ISS) have replaced Saturday in space defective pump station to stop an ammonia leak in an emergency mission unprecedented, but it may take months to see if the problem was finally resolved. Ammonia is used to cool the channels through which passes power station produced by solar panels.

mission astronauts Tom Marshburn and Chris Cassidy completed more quickly than expected, took place in five hours. Started at 13 h 44, the repair was completed at 19 h 14, said Nasa. “Marshburn and Cassidy are back to the ISS,” he tweeted on his account the U.S. space agency. About three hours after the start of the mission, two astronauts were able to replace the faulty pump. “The new pump is installed and working,” then said Nasa.

An hour later, they operated and found after 30 minutes of observation no signs of ammonia leak. “No leaks! We bring Tom and Chris inside”, immediately tweeted Chris Hadfield, ISS commander who oversees the operation. However, the agency warns that it “will monitor the pump longer to determine whether replacement has stemmed the leak,” according to a statement. The two men, to guard against any contamination, then waited until the sun burns traces of ammonia on their suits before joining the station.

NASA stressed that the lives of six occupants of the ISS was not in danger while admitting that the incident was “serious”. According to experts, the 168th spacewalk is unprecedented because it was prepared in a very short time. In a press briefing, the Flight Director of ISS, Joel Montalbano, noted that the astronauts had done “a fantastic job” but “will take weeks, four or five, maybe more, before to be 100% sure of the diagnosis. ” “For weeks or months, it is too early to say. But it will take time,” he added.

For Norm Knight, however, the Flight Director of NASA, this release sets a precedent is “probably one of the fastest” in the history of the U.S. space agency . American astronauts have a rich experience of spacewalks and each has to his credit more than 18 hours of “spacewalk”. The Russian space agency Roskosmos has compared a Saturday spacewalk to “a new flight in a small spacecraft” and “walk in orbit which is not among the easiest.” “Wearing their suits that weigh more than 100 kg, the astronauts move on their arms. After each trip, as they go after a good battle with arms covered with bruises and blisters on his shoulders,” said the Director of flights of the Russian segment of the ISS, Vladimir Soloviev.

The current ISS crew alerted Thursday the command center of the station, based in Houston (Texas), the presence of “small white flakes floating around the station “. Images provided by the crew confirmed the leak from a cooling system, already defective November 1, 2012. Vladimir Soloviev had called Friday the leak detected in the U.S. segment of the station of “very serious mistake”. The director of programs run in Roskosmos, Alexei Krasnov, however, had downplayed the severity of the incident noting that ammonia leaks were fairly common on the ISS: “This is not the first time that this occurs, unfortunately. “

addition Americans Marshburn and Cassidy and the Canadian Hadfield, the current crew of the ISS has the Russians Roman Romanenko and Alexander Vinogradov Missourkine. The return to Earth of three astronauts Tuesday – Romanenko, Marshburn and Hadfield – is not questioned, said NASA

.