It is prohibitively expensive to send building materials from Earth to Mars, which is why future habitats will need to be constructed primarily using materials already found on the Red Planet. According to research from the University of Manchester, compounds from urine and blood produced by astronauts may play a key role in this construction process.
Mars is covered in soil called regolith that can be used to create concrete for shelters and other buildings. Rather than just mixing this material with water, however, future efforts to produce building materials on the Red Planet may also include protein from blood plasma and urea from urine and sweat.
Combining the Martian dust with compounds from blood and sweat resulted in a material stronger than the typical concrete used on Earth, according to the study. The researchers call their material ‘AstroCrete,’ noting that of the materials created, the best-performing sample had a compressive strength of 40 Megapascals; that’s considerably higher than ordinary concrete’s 20 – 32MPa strength.
A six-person crew on Mars could contribute the biological materials needed to produce around 1,100lbs of the AstroCrete material in two years, the study estimates. The amount of the Martian concrete produced would expand with each new crew member added to a long-term mission, producing greater amounts of concrete for building expansions.
The concrete recipe may prove more useful than other suggested building methods for future Mars missions, including ones that involve 3D printing systems or other types of regolith-based building materials. The idea of mixing blood with soil to make concrete isn’t new — ancient civilizations used animal blood as a binder in their mortars, for example.