What had been a peaceful and productive mission for the six men aboard the Russian space station Mir, including U.S. astronaut Jerry Linenger, nearly became a tragic nightmare during the evening of Feb. 24, 1997. A lithium-perchlorate canister, designed to generate oxygen via a chemical reaction, suddenly burst into flames when activated. Although the fire was quickly subdued, a dense, life-threatening smoke—different in form and movement from its gravity bound counterpart on Earth—rapidly filled the station. Being confined in a limited area 360 kilometers (224 miles) above the nearest fire brigade made the situation even more precarious. “You can’t just open a window to ventilate the room,” commented cosmonaut Aleksandr Lazutkin in a NASA report about the incident.