(NEXSTAR) – There are currently seven people zipping through space aboard the International Space Station, all trying to work, eat, exercise and live alongside one another within the airtight confines of the station’s habitable areas.
So let’s talk about what it might smell like up there.
Astronauts who have previously visited the ISS have not been shy about the odor on the space station, with many describing it as a one-of-a-kind aroma.
Speaking with Wired magazine in 2017, former NASA astronaut Scott Kelly likened the odor to a jail he once visited, describing it as a “combination of antiseptic, garbage and body odor.” He then attempted to clarify that the astronauts themselves don’t stink much, but rather their workout clothes.
“We use deodorant, we wipe, rinse off, shower. But there’s a little body odor going on for sure. Mostly it’s just exercise clothes people wear for a couple weeks without washing,” Kelly said.
A few years earlier, he told CBS News that different areas of the ISS were more pungent than others — an opinion shared by Samantha Cristoforetti, an Italian astronaut with the European Space Agency. Cristoforetti, during her second stint on the ISS in 2022, explained on TikTok that the ISS has a “very peculiar odor” but there are “a couple of places” that can get smellier.
Among those places on the plane that can get a little stinkier, Cristoforetti identified the areas where they store their trash, their containers of solid human waste, and the area near the exhaust of their “brine processor,” which removes the water from their urine.
NASA astronaut Bob Hines, who lived on the ISS with Cristoforetti in 2022, said his first whiff of the ISS was a mixture of “old luggage” and a “hospital-type smell,” he told Boston’s Museum of Science. The reason for the former, he said, was because of the many cargo bags stored throughout the station, while the latter was due to the crew’s cleaning and sanitation protocols.
Of course, NASA is always looking for ways to mitigate the odors. The space agency relies on air filters to remove not only carbon dioxide, but gases produced by scientific experiments and human bodies. And engineers and chemists with NASA have also researched ways to contain bad odors before they become distractions for crew members.
“We really want astronauts to be able to focus on their job,” Susana Tapia-Harper, who managed the odor lab at NASA’s test facility in New Mexico, told WHYY of their work in 2021. “If you can imagine if you had to do your homework in a nasty bathroom, it would be hard to concentrate. So that’s the kind of situation we want to avoid for our astronauts.”
These mitigation efforts are also likely why some of the same astronauts who spoke of the smells on the ISS — Kelly, Cristoforetti, Hines — say they aren’t all that terrible, despite their initial impressions.
Cristoforetti called the air filters “very good” and claimed she wasn’t able to detect any consistent smells “within a matter of days” after arriving. And Hines said “you don’t even notice it” after a while.
Canadian astronaut Chris Hadfield once went as far as saying that the ISS has a “pretty clean” smell, like one that a person might encounter when walking “onto an airplane” or into a “nice clean hospital building.”
“We work hard to keep it smelling good and healthy. It’s good for our health, and doesn’t let any bacteria grow,” Hadfield continued. “And it’s better if it doesn’t have a smell that you don’t like.”
