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How do you poop in space?

In space, everything is different. Off the planet, the most basic human biological processes can be a challenge, partly because of the lack of gravity.

Find out how our dear astronauts can satisfy their natural needs on board the International Space Station.

faire caca dans l'espace

23 million dollars (around 20 million euros),
that is the price of the toilets which were installed on the ISS during 2020.

toilettes de la station spatiale internationale en 2020

As you can imagine, go to the toilets in the International Space Station is not as easy as down here on Earth.
On platforms such as the ISS, where astronauts live and work for long periods of time, toilets known under the name of ‘Universal Waste Management System’ (UWMS) recycle urine in order to produce water for a future use.
For shorter missions, such as Artemis II, waste is stored for later disposal.
These new toilets were designed following feedback received from astronauts on their comfort and ease of use.
They are 65% smaller and 40% lighter than the previous toilets of the space station.
For instance: the toilets now have a seat, which will delight women.

According to Melissa McKinley, Advanced Exploration Systems Logistics Reduction Project Manager at NASA, the key of this equipment is looking to “optimize mass volume and power usage, which are all very important components of a spacecraft design”.

In practice…

vidéo de samantha cristoferreti sur le toilettes de l'iss

In the absence of gravity, residents of the International Space Station use an appropriate device vacuuming the waste, whether liquid or solid. There are two ways of proceeding.

In the video above, you can see the two main systems in action.
The pipe in a shape of a funnel is used when the astronauts urinate, it collects urine in order to recycle it in drinking water thanks to the “Urine Processor Assembly”, water being a limited resource in space.
When they have to poop, astronauts have a “seat” at their disposal. Realistically, it’s a not a system very easy to use due to the lack of weightlessness.
It is a procedure taking some practice, that is why it is part of the training of the astronauts before they go on a mission in space.
Once they have found the best position possible, the astronauts activate the mechanism which is a suction system made for evacuating heavy waste. .
The waste is then stored in a compartment of the ISS provided for that purpose, before being sent in the atmosphere in order to be disintegrated.

So, the next time you see a shooting star…it might not be what you think.

Even at 200 million dollars, the toilets of the ISS can break down. It was one of the first interventions of Thomas Pesquet and his colleague Peggy Whitson at his arrival on board the ISS.

concours pour régler le problème du caca dans l'espace

SPACE POOP CHALLENGE, a contest to solve the problem of
« poop in space »

At the end of 2016, the NASA launched a contest seeking a system collecting organic waste from astronauts when wearing their spacesuits.

The problem was brought to light on the occasion of the flight of the French astronaut Thomas Pesquet to the International Space Station (ISS). With its colleagues, before arriving safely on November 20, they stayed in their capsule deprived of toilets during 48 hours.

The reward offered by the NASA was $30,000.

The instructions were simple: they required a system operating inside of a spacesuit, capable of collecting urine, faeces and menstrual fluid for a period of 144 hours, that is to say 6 full days.
It had to be a stand-alone system so that the astronauts could keep their hands free during the manoeuvre.

After reviewing around 5,000 proposals, the NASA has found its winner. His name is Thatcher Cardon and he is a doctor for the American air force.

Its invention consists in a small opening in a shape of an airlock which would allow the astronauts to extract the diapers and replace them, but also change their underwear very discreetly.

Two other ideas caught the attention of the NASA. The first one came from a trio of researchers who imagined a waste disposal system working thanks to air pressure.
The second idea came from an English designer. He created a disinfecting underwear offering waste management.

The NASA now has to develop several prototypes to send them on the International Space Station for testing purposes.