Astronauts could use their own urine to build moon bases one day

Will future lunar homes be made with the help of human urine? (Image credit: ESA, Foster and Partners)

When humans return to the moon to stay, where will they live? Well, it turns out they might live in lunar bases made of astronaut pee.

In a new study, researchers have found that urea, the major organic compound found in human urine, could be useful for making concrete for lunar structures.

Obviously, many people might immediately think: Why!? We seem to have no issue making concrete without urine in it here on Earth, why would urea be important in making concrete on the moon?

Video: Astronauts drink recycled urine and celebrate
More: Skywatcher spots astronaut pee in space

A 3D printing device used in this recent study. — A 3D printing device used to create construction material made in part from human urine. A similar technique could one day be used for moon bases. (Image credit: Shima Pilehvar et al./ Journal of Cleaner Production)

Well, the surface of the moon is a lot harsher than the Earth's surface. From extreme temperature fluctuations to radiation and the occasional meteorite impact, future astronauts living on the moon's surface will have to endure much more intense conditions. This means that the buildings they live in will have to be able to withstand the pitfalls of this unique environment.

Additionally, when considering lunar building materials, researchers have to consider how heavy it might be to transport from Earth to the moon and whether it can be 3D printed, because scientists are currently considering 3D printing as a method for building on the lunar surface.

In this new study, researchers from Norway, Spain, the Netherlands and Italy, in cooperation with the European Space Agency (ESA), conducted a number of experiments testing the use of urea from human urine as a plasticizer — a substance that can be added to materials like concrete to make it more flexible before it hardens.

Researchers tested possible lunar building materials with urea from human urine as a plasticizer. They compared the urea mixture to mixtures with other plasticizers. (Yes we know what it looks like.) (Image credit: Shima Pilehvar et al. / Journal of Cleaner Production)

To create and test the use of urea as a plasticizer, the team used a material developed by ESA that is similar to lunar regolith, or loose material from the moon's surface. They tested the material with urea and with other plasticizers, seeing how much weight it could support, testing its resistance after heating the materials to 176 degrees Fahrenheit (80 degrees Celsius) and went further to test it after repeatedly freezing and thawing it to replicate the extreme temperature cycles that happen on the moon's surface.

"We have not yet investigated how the urea would be extracted from the urine, as we are assessing whether this would really be necessary, because perhaps its other components could also be used to form the geopolymer concrete," Anna-Lena Kjøniksen, one of the researchers from the Norwegian university, said in a statement. "The actual water in the urine could be used for the mixture, together with that which can be obtained on the Moon, or a combination of both."

The team found that samples that used urea as a plasticizer were able to support heavy weight, remain stable and keep their shape. So, while the team will be testing this concept further to figure out what the best building material for future lunar structures will be, they got some promising results with this study.

This work was published Feb. 20 in the Journal of Cleaner Production.

Follow Chelsea Gohd on Twitter @chelsea_gohd. 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.

Chelsea “Foxanne” Gohd joined Space.com 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.

More about tech robots

Ruko F11PRO 2 drone review

Meta Quest 3S review: Fantastic VR performance at a budget price

SpaceX Falcon 9 rocket launches Starlink satellites from California, lands on ship at sea

See more latest

5 Comments Comment from the forums

fr rapp

this stands to reason of a sort, if i remember right the Romans used pig blood (we hope) to mix in to their concrete to make it set up under water , a similar process with urine or perhaps chemicals found on the moon or mars might help to make stronger structures we need to be doing comprehensive analysis of the available chemicals and how to extract them now before we try building on these hostile environments
Reply
Stacklightning2

That's go

Admin said:
When humans return to the moon to stay, where will they live? Well, it turns out they might stay in buildings made out of astronaut pee.

Astronauts could use their own urine to build moon bases one day : Read more
That's going to require a lot of water!
It might be more practical to build their accommodation out of food...
Reply
dfjchem721

It would take a lot of urine to build up structures like this. It would seem a lot easier just to take urea up in bulk then relying on people peeing into a "community urine jug" to slowly build up the structure.

Better idea:

Don't send humans at all since they are so costly to maintain. Do everything with robots, which are 1000x cheaper and can do just about everything people can. With all the advanced electronics and sensors being developed, the robots would be equally successful at returning data and material from the moon than any manned mission. Keep the cost low, and use all those spared funds to deal with all the problems on the moon's neighbor, Mother Earth. There are a lot of problems on Earth, in case people haven't been paying attention.

Humans on the moon - been there, done that!
Reply
fr rapp

dfjchem721 said:
It would take a lot of urine to build up structures like this. It would seem a lot easier just to take urea up in bulk then relying on people peeing into a "community urine jug" to slowly build up the structure.

Better idea:

Don't send humans at all since they are so costly to maintain. Do everything with robots, which are 1000x cheaper and can do just about everything people can. With all the advanced electronics and sensors being developed, the robots would be equally successful at returning data and material from the moon than any manned mission. Keep the cost low, and use all those spared funds to deal with all the problems on the moon's neighbor, Mother Earth. There are a lot of problems on Earth, in case people haven't been paying attention.

Humans on the moon - been there, done that!
and when we have another 5 billion people where do we put them or feed them getting colonies on other worlds is the only way to solve the problems. just try and tell a catholic they have to practice birth control
Reply
dfjchem721

Let's see what our options are:

1) Go to distant, totally barren, hostile planet with resupply depending on another distant planet. That distant planet is going bad with over -crowding (as noted above) and will likely give you up for lost over time - so no hope of surviving long-term on barren planet. (Please don't respond with terraforming and other idiotic notions vastly beyond our abilities. I see enough of that in sci-fi movies.)

2) Stay where you are, spend money on remediation and/or let mother nature take care of over-crowding etc. and hope for survival rather than going to distant barren hostile planet and assure your demise.

Tough call. I will go with # 2.
Reply

Show more comments

Get the Space.com Newsletter