The International Space Station has a radiator leak in its power system. The outpost’s commander has called the situation serious, but not life-threatening.On Thursday the six-member crew noticed white flakes of ammonia leaking out of the station. Ammonia runs through multiple radiator loops to cool the station’s power system. Nasa said the leak is from one previously leaking loop that can be bypassed if needed, and that fixing the leak might require that a portion of the station’s cooling system be shut down for about 48 hours. Nasa spokesman Bob Jacobs said engineers are working on rerouting electronics just in case the loop shuts down. The Earth-orbiting station has backup systems.Space station commander Chris Hadfield of Canada tweeted that the problem, while serious, was stabilised.The space station always has enough emergency escape ships for the crew, but there are no plans to use them.