On the morning of January 14, NASA officials received warnings that dangerous ammonia gas was leaking into the US segment of the International Space Station.
Ammonia is used on the exterior of the space station to cool the electronics powering the station. In an interview with the New York Times, ISS Program Manager Michael Suffredini said, “While it’s inconvenient for the crew to be in the Russian segment, it’s certainly not unhealthy for them.”
American astronauts were immediately evacuated to the Russian segment of the station after the first warnings were triggered in the Mission Control office, and NASA flight controllers shut off all non-essential equipment. Minutes later they were given an “all-clear” signal and were sent back to their segment, only to be evacuated back to the Russian segment shortly after, when readings indicated it was still unsafe for the astronauts.
In an interview with BBC News, NASA Spokesman Bob Jacobs said, “We protected for the worst case scenario.” After the initial scare calmed, Italian astronaut Samantha Cristoforetti tweeted from the ISS, saying, “Hey everybody, thanks for your concern. We’re all safe and doing well in the Russian segment.” Canadian astronaut Chris Hadfield also took to social media to assure the public that everything was under control, tweeting, “Ammonia is used for cooling through pipes & heat exchangers on the outside of station. We train for it & the crew and MCC (mission control center) have responded well.”
On the morning of January 15, NASA flight controllers determined that the gas leak was a false alarm and sent the astronauts back into the US segment of the station.
Half of the crew arrived in September, and the other half in November as part of Expedition 42; a research mission sent to conduct experiments “focusing on the effects of microgravity on cells, Earth observation, physical science and biological and molecular science,” according to NASA’s website, nasa.gov. The mission is set to last until May 14, and is expected to reveal much information on the effects of low-gravity on the human immune system.