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Space station astronaut marks World Toilet Day with an explainer

To mark World Toilet Day on Sunday, current space station inhabitant Andreas Mogensen has answered one of the most common questions that astronauts get asked: “How do you use the bathroom in space?”

The microgravity conditions aboard the International Space Station (ISS) make it impossible to use a conventional toilet on the orbital outpost. You don’t even want to imagine the mess it would create.

So engineers had to come up with something that takes human waste away at speed before it has a chance to float away and contaminate the environment.

“If you have ever wondered how going to the toilet works on the ISS, I have made a little video explaining the procedure that is needed to go number 1 and 2 on the toilet up here,” Mogensen said in a social media post shared on Sunday.

Today is World Toilet day, which celebrate and highlights the throne that we all sit on every day. And if you have ever wondered how going to the toilet works on the International @Space_Station, I have made a little video explaining the procedure that is needed to go number 1…

— Andreas Mogensen (@Astro_Andreas) November 19, 2023

The video (above) shows how a suction cup is used to take away urine, which, incidentally, is treated before being recycled as drinking water for the ISS crew. For solid waste, the astronaut sits on a small contraption that includes charcoal to stop strong odors from escaping.

The waste is captured in a bag that the astronaut then seals. It can’t be reused for anything so it’s vacuum-dried and compressed in airtight containers before being ejected from the station with other waste, which then burns up in Earth’s atmosphere.

The ISS has three toilets for a crew that usually comprises around six astronauts.

The European Space Agency also released a couple of infographics on the same subject:

An infographic about the toilets on board the space station.
An infographic about the toilets aboard the ISS.

World Toilet Day is a United Nations-supported event that aims to inspire action to improve conditions among the more than four billion people who still live without safely managed sanitation.

“Having a functioning toilet in space reminds me that not all are fortunate enough in the world to have access to such a luxury or even clean water,” Mogensen said in his post.

For more insight into how astronauts live and work aboard the ISS, check out these videos made by visiting crewmembers from over the years.

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