WASHINGTON -- NASA says it is looking into a problem with a malfunctioning cooling pump on the International Space Station, but there is no immediate danger to the six crewmen on board.
Agency spokesman Kelly Humphries says the problem may eventually be serious, but is not an emergency at the moment.
Humphries says the faulty external pump stopped working on one of the two cooling systems aboard the orbital outpost. The backup system is operating as it should.
Humphries says as a precaution, the three Russians, two Americans and one Japanese crew members aboard shut down some minor operating systems to reduce the power load.
Sources say a software fix is being attempted but the problem is likely within the pump itself.
The systems pump ammonia coolant to equipment inside and outside the station to keep it cool.
The crew is beginning a normal sleep cycle while ground controllers troubleshoot the problem.