International Space Station has 'peculiar odor,' astronaut says

News
By
published

The smell is easy to get used to, but you should still avoid the trash and the toilet.

European Space Agency astronaut Samantha Cristoforetti takes in the scent of edible plants growing in the eXposed Root On-Orbit Test System (XROOTS) experiment on the International Space Station.
European Space Agency astronaut Samantha Cristoforetti takes in the scent of edible plants growing in the eXposed Root On-Orbit Test System (XROOTS) experiment on the International Space Station. (Image credit: ESA)

Call it the scent of space.

There's a persistent "peculiar odor" on board the International Space Station (ISS) that takes a few days to get used to, according to European astronaut Samantha Cristoforetti.

"When I got here a couple of months ago for my second flight, I could immediately smell a very peculiar odor that brought me back instantly to the memories and sensations of my first flight's odors," Cristoforetti shared on TikTok Monday (July 25). "But within a matter of days, I got used to it, and now I cannot smell it anymore."

Related: Astronaut Samantha Cristoforetti makes history with 1st TikTok from International Space Station

Cristoforetti didn't elaborate on what the ISS smells like, although she did note the capable filters of the space station eliminate most odors. (Cristoforetti finished her first spacewalk July 21, days before the video was posted.)

Other astronauts have commented on space smells like gunpowder or ozone, particularly because atomic oxygen is believed to cling to spacesuits in a vacuum. 

Cristoforetti also gave aspiring ISS visitors a rundown of the smelly places to avoid on the space station. In June, the orbiting lab's Expedition 67 crew packed trash high within a Northrop Grumman Cygnus freighter about to depart the ISS for a fiery re-entry. "Of course, that can be smelly," she said of the garbage-filled spacecraft.

Related stories:

— This is the astronaut's video guide to going to the bathroom in space
— The scoop on space poop: How astronauts go potty
— SpaceX's Dragon space toilet is off limits for astronauts returning to Earth soon

Other adverse aromas emanate from the space station's toilet. The toilet is designed to recycle pee into drinkable water; there's always a remainder after this process completes, however. The system evaporates whatever leftover urine remains, and the exhaust can be smelly "in spite of this big filter," Cristoforetti said.

But the European Space Agency astronaut reassured her 600,000 TikTok followers that, aside from these troublesome areas, the ISS is free from fearsome fragrances. "Other than that, the space station smells very pleasant," she said.

Follow Elizabeth Howell on Twitter @howellspace. Follow us on Twitter @Spacedotcom and on Facebook. 

Join our Space Forums to keep talking space on the latest missions, night sky and more! And if you have a news tip, correction or comment, let us know at: community@space.com.

Elizabeth Howell
Elizabeth Howell
Former Staff Writer, Spaceflight (July 2022-November 2024)

Elizabeth Howell (she/her), Ph.D., was a staff writer in the spaceflight channel between 2022 and 2024 specializing in Canadian space news. She was contributing writer for Space.com for 10 years from 2012 to 2024. Elizabeth's reporting includes multiple exclusives with the White House, leading world coverage about a lost-and-found space tomato on the International Space Station, witnessing five human spaceflight launches on two continents, flying parabolic, working inside a spacesuit, and participating in a simulated Mars mission. Her latest book, "Why Am I Taller?" (ECW Press, 2022) is co-written with astronaut Dave Williams.