On November 23, 2024, Russian astronauts aboard the International Space Station (ISS) encountered an unexpected toxic odor upon opening the hatch of the Progress MS-29 cargo spacecraft. NASA reported that the crew also observed small droplets inside the module.
Following the discovery, the hatch to the Poisk module was promptly closed to isolate the remaining section of the Russian segment of the ISS. NASA stated that air quality was monitored using air purifiers and contaminant sensors.
Don Pettit, a NASA astronaut, described the smell as reminiscent of spray paint. By November 24, flight controllers in Houston announced that air quality had returned to normal levels. However, some experts, including Anatoly Zak from Russian Space Web, suggested that NASA may have downplayed the incident, asserting that the odor was indeed toxic.
NASA confirmed there was no threat to the crew and that astronauts were working to reopen the hatch between Poisk and Progress. The exact cause of the odor remains unknown, but speculation points to a potential leak from the spacecraft's cooling system.