How will astronauts poop on the moon? New NASA challenge aims to flush this mystery

NASA's new contest challenges innovators to come up with a brand new space toilet design. (Image credit: NASA/HeroX)

It's no secret that humans poop — even in space. 

But the actual, physical act of going to the bathroom while floating in space can be tricky, to say the least. In a new contest, NASA is calling on innovators from around the world to develop a new space toilet that would work not just in microgravity such as aboard the International Space Station, but also in lunar gravity aboard a future lunar lander as part of NASA's Artemis program which aims to return humans to the moon by 2024. The contest has a total prize purse of $35,000 to be shared by winning teams.

"This challenge hopes to attract radically new and different approaches to the problem of human waste capture and containment," NASA wrote in an overview of the challenge, titled "NASA's Lunar Loo Challenge." 

The challenge is being overseen by the NASA Tournament Lab and organized on the HeroX crowdsourcing site.

Video: Space Toilet Technique: NASA's How-To Guide (Video)
More: How to Pee in Space (and What to Do If the Toilet Breaks)

Anyone can apply to this challenge and the winning design will receive a $20,000 prize, the second-place design will win $10,000 and the third-place winner will win $5,000. The contest even includes a "junior" category in which children (anyone under the age of 18) can apply with their innovative space toilet idea. Children in the junior category can win "public recognition and an item of official NASA-logoed merchandise," according to the challenge overview. 

Specifically, the contest calls for designs that work in lunar gravity, which is about one-sixth Earth's gravity and microgravity. Designs should also take up no more than 4.2 cubic feet (0.12 cubic meters) of space and shouldn't be louder than 60 decibels (that's about the same volume as a bathroom fan on Earth, according to the same statement). 

The space toilet will have to be able to collect both urine and feces at the same time and hold at least a quarter gallon (1 liter) of liquid waste and 17.6 ounces (500 grams) of solid waste. The device also has to be able to capture at least 114 grams of menstrual blood per day. 

Related: SpaceX has a new space toilet for astronauts. But how does it work?

The final requirements are that the system must be able to store or get rid of waste and should be able to be cleaned and maintained "with 5 minute turnaround time or less between uses," the statement reads. 

Hopefully, this next-gen space toilet will be a major step up from some of the more, ahem, challenging waste removal systems that have been used in space throughout human spaceflight history. 

During NASA's Apollo program in the 1960s and early 1970s, astronauts would urinate into a "relief tube" (designed only for male astronauts, since women were not yet allowed in NASA's astronaut corps) which they would dispose of urine into space where the urine would freeze. Apollo astronauts would also have to figure out how to get their solid waste into plastic bags which they had to bring back to Earth to be studied. 

The space shuttle had toilets known as the Waste Collection System, which emptied waste out into the vacuum of space. But it didn't always work perfectly. The International Space Station improved on the space toilet with a new design, and NASA is working on a new space toilet known as the Universal Waste Management System (UWMS).

To learn more about NASA's Lunar Loo challenge, including rules and registration requirements, visit the contest website here.

Email Chelsea Gohd at or follow her on Twitter @chelsea_gohd. Follow us on Twitter @Spacedotcom and on Facebook.

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Chelsea Gohd
Senior Writer

Chelsea “Foxanne” Gohd joined in 2018 and is now a Senior Writer, writing about everything from climate change to planetary science and human spaceflight in both articles and on-camera in videos. With a degree in Public Health and biological sciences, Chelsea has written and worked for institutions including the American Museum of Natural History, Scientific American, Discover Magazine Blog, Astronomy Magazine and Live Science. When not writing, editing or filming something space-y, Chelsea "Foxanne" Gohd is writing music and performing as Foxanne, even launching a song to space in 2021 with Inspiration4. You can follow her on Twitter @chelsea_gohd and @foxannemusic.

  • kristianna276
    The poop on the issue. When it comes to space the prevailing view is, space is for professionals and please don't try this at home. If we as a developing space ferrying society, we need to think of what "human" cities would be like. Whether the cities have a population of 1000 or one million, it all boils down to infrastructure and technology. How does water flow in microgravity, or do we use water in getting our <<stuff>> together. There are many techies that are developing better water purification systems here on Earth. The only problem is that they seem to go no where outside the lab, and nothing changes in the wake of these new techniques. What happens when you are transporting 900 + passengers to Luna or Mars? How much water, food and means of dealing with all the human waste? Astronauts will forever play a vital role in space exploration, but the rest of us peons should never be taken for granted.