Commander Chris Hadfield has taken to Twitter to explains that there's an emergency aboard the International Space Station. Apparently high-pressure ammonia may be leaking inside the station.
The crew has currently sought refuge in theRussian segment, having closed the hatches behind them. Hadfield says they are "safe for now," but the situation is being analyzed.
He's gone on to explain that the ammonia leak, which is used for cooling the space station, is one of the big three disasters that can hit the Space Station. It's usually indicated by a rise in pressure within the station. He also adds that the crewe is highly trained for these events, and that they are "calm, together, and working on the problem."
NASA points out that "no ammonia leak confirmed. Crew responded to coolant loop pressure increases."
Update 7:42AM EST: NASA is now saying that "flight controllers are not sure if the alarm was triggered by a pressure spike, a faulty sensor, or a problem in a computer relay box." Sounds like there might not be an ammonia leak.
Update 8:11AM EST: In an announcement, NASA has said that there is "no concrete data that there was an ammonia leak." There's no ammonia inside thee ISS, fortunately, though it's still unclear whether pressure spike was real or a sensor problem. That's being investigated. Clearly, things are fairly calm up there: Mission Control told the astronauts aboard ISS to "enjoy the impromptu day off."