Call it the smell of space.
According to European astronaut Samantha Cristoforetti, there is a persistent “specific smell” on board the International Space Station (ISS) that takes a few days to get used to.
“When I arrived here a couple of months ago for my second flight, I immediately noticed a very specific smell that instantly brought me back to the memories and smells of my first flight,” Cristoforetti shared on TikTok. (will open in a new tab) Monday (July 25). “But in a matter of days I got used to it and now I don’t smell it.”
Related: Astronaut Samantha Cristoforetti makes history with the 1st TikTok from the International Space Station
Cristoforetti did not elaborate on what the ISS smells like, although she did say that the space station’s filters are capable of eliminating most odors. (Cristoforetti completed her first spacewalk on July 21, days before the video was posted.)
Other astronauts have talked about cosmic smells like gunpowder or ozone, especially because atomic oxygen is thought to stick to spacesuits in a vacuum.
Cristoforetti also gave novice ISS visitors a rundown of stinky places to avoid on the space station. In June, the crew of the Expedition 67 orbital laboratory loaded debris inside the Northrop Grumman Cygnus cargo ship, which was about to leave the ISS for a fiery return. “Of course it can be smelly,” she said of the spaceship filled with debris.
Other unpleasant odors coming from the space station bathroom. The toilet is designed to convert urine into drinking water; however, there is always a residue left after this process is completed. The system vaporizes any remaining urine, and the exhaust can be smelly, “despite that big filter,” Cristoforetti said.
But a European Space Agency astronaut reassured her 600,000 TikTok followers that, aside from these problem areas, there are no frightening scents on the ISS. “Besides that, the space station smells really nice,” she said.
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