(HOUSTON) -- NASA engineers are working to troubleshoot a cooling system failure on the International Space Station. One of the cooling systems on the ISS has been shut down because of temperature fluctuations, cutting the artificial satellite's cooling ability in half.
"What appears to be the flow control valve inside one of our pump units got a little cold earlier today and there was an automatic shutdown," Kelly Humphries of Johnson Space Center in Houston, Texas explained Wednesday.
There are six people onboard the International Space Station and they're all doing fine, Humphries told ABC News Wednesday.
"Two Americans, one Japanese astronaut and three Russian cosmonauts" are onboard the space station, he said.
While Humphries said there is no immediate danger for the astronauts and that they do not need to come home, he added that engineers are still looking at the data and trying to understand what happened. They're preparing to do some additional troubleshooting, but the engineers do not expect their investigation will threaten the safety of the six onboard. Shutting down the modules -- Kibo, Columbus and Harmony -- means that the six astronauts will have to stay in the other modules for now, NASA said.
Officials don't know yet whether the problem resulted from a software glitch or involves hardware, so it's unclear whether a space walk will be needed to resolve the issue.
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