"Crew informed by controllers that it's staring to look like a false indication, either a faulty sensor or computer relay," NASA said on its Twitter blog.
"ISS crew inside Russian segment after a coolant pressure alarm. No signs of a leak. Controllers are assessing," NASA said in a Twitter recap.
Russia’s space agency, Roscosmos, said earlier that ammonia from an air conditioning unit in the American segment of the ISS could have been discharged into the station’s atmosphere. The American segment is currently isolated, the crew is safe and located in the Russian segment.
Earlier in the day, a NASA source told RIA Novosti that the station's atmosphere was being checked remotely, but the only data available was the information from the cooling circuit itself, indicating that the pressure of ammonia had fallen.
The current ISS crew comprises six specialists from the United States, Russia and the European Union. It includes mission commander Barry Wilmore and flight engineer Terry Virts from NASA; flight engineers Elena Serova, Alexander Samokutyaev and Anton Shkaplerov from Roscosmos; and flight engineer Samantha Cristoforetti from the European Space Agency (ESA).
