Search Here

NASA announced two astronauts will make an unscheduled spacewalk early Saturday in a bid to troubleshoot a leak in a cooling system on the international space station.

The orbital laboratory and the six astronauts aboard are not in danger, NASA said. But one of its eight solar-powered electrical systems has been shut down because of the leaking ammonia, a coolant that is streaming from an unseen source and sending flakes of ammonia snow drifting into space.

This is not the first time that a minor leak of ammonia has occurred - there was another occurrence in 2007, and NASA has been studying the issue ever since. Mission Control has been in contact with the ISS regarding the issue.

"It is in the same area, but we don't know whether it's the same leak," NASA spokesman Kelly Humphries of the Johnson Space Center in Houston told SPACE.com. Humphries said the agency was 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. In fact, the leak has worsened to the point that Mission Control expects that particular loop to shut down within the next 24 hours.

However, "the crew is in no danger," Humphries stressed. It's too soon to speculate on a possible spacewalk or other measure to deal with the issue, he added.