Emergency Spacewalk Likely Saturday to Fix 'Very Serious' Leak On International Space Station

Astronauts aboard the International Space Station are mulling an emergency spacewalk to fix an ammonia leak that one official described as "very serious."

The six astronauts aboard the space station are said to not be in any danger and NASA is looking into the problem, which was spotted Thursday.

Ammonia is used as a coolant for the station's power system. This is not the first time the crew aboard the ISS has dealt with an ammonia leak. A minor ammonia leak was discovered in 2007 and NASA has been studying the problem ever since, Discovery News reported. In November 2012 astronauts took a spacewalk to troubleshoot a similar leak.

"This ammonia loop is the same one that spacewalkers attempted to troubleshoot a leak on during a spacewalk on November 1, 2012," a NASA statement said.

"It is not yet known whether this increased ammonia flow is from the same leak, which at the time, was not visible."

NASA spokesman Kelly Humphries of the Johnson Space Center in Houston told SPACE.com that the leak "is in the same area, but we don't know whether it's the same leak."

Vladimir Solovyov, flight director for the Russian segment of the space station was quoted by Interfax news agency saying, "Indeed, they have a serious defect, very serious,"

NASA is taking the leak seriously because it affects an important system - if they lose the ability to cool that particular solar array, it won't be able to generate power for the station, Humphries said.

There is no official announcement for when the spacewalk to repair the leak will occur, but a NASA statement indicated it could be as soon as Saturday, NASA reported.

According to NASA, "Chris Cassidy and Tom Marshburn began preparing for the possible spacewalk to inspect the area it appears the leak is originating from, and potentially make repairs to the leaking ammonia cooling loop. Station managers are meeting this morning and will meet again tonight to discuss procedures and timeline work for a spacewalk, if approved."