It can cost more than 100 million rubles to transport a single brick to Mars, so building a Martian colony in the future seems prohibitively expensive. Scientists at the University of Manchester have developed a way to potentially overcome this problem by creating a concrete-like material from extraterrestrial dust, as well as the blood, sweat and tears of astronauts.
In their study, published today in Materials Today Bio, human blood protein combined with the composition of urine, sweat or tears can glue simulated lunar or Martian soil to create a material that is stronger than conventional concrete, ideal for construction work in extraterrestrial environments. …
The cost of transporting one brick to Mars is estimated at about $ 2 million, which means that future Martian colonists cannot bring their own building materials with them, but will have to use the resources they can obtain locally to build shelters. This is known as in-situ resource use and usually focuses on the use of loose rock and Martian soil (known as regolith) and thin water sediments. However, there is one overlooked resource that, by definition, will also be available on any crewed mission to the Red Planet: the crews themselves.
In an article published today in Materials Today Bio, scientists demonstrated that a common plasma protein - human serum albumin - can act as a binder for simulated lunar or Martian dust, creating a concrete-like material. The resulting new material, called AstroCrete, had a compressive strength of up to 25 MPa (megapascals), about the same as 20-32 MPa for conventional concrete.
However, scientists have found that the inclusion of urea - biological waste that the body produces and excretes in urine, sweat and tears - can further increase compressive strength by more than 300%, with the most effective material having a compressive strength of nearly 40 MPa., is significantly stronger than conventional concrete.
Dr. Aled Roberts of the University of Manchester, who worked on the project, said the new method has significant advantages over many other proposed construction methods on the Moon and Mars.
“Scientists have tried to develop viable technologies to produce materials like concrete on the surface of Mars, but we never stopped thinking that the answer could be within us all the time,” he said.
Scientists estimate that over 500 kg of the high-strength AstroCrete could be produced during a two-year mission to the surface of Mars by a team of six astronauts. When used as sandbag mortar or regolith fused bricks, each crew member could produce enough AstroCrete to expand the habitat to support an additional crew member, doubling the available housing with each successive mission.
Animal blood has historically been used as a binder for a solution. “It's amazing that the main problem of the space age may have found a solution based on the inspiration of medieval technology,” said Dr. Roberts.
Scientists investigated the underlying binding mechanism and found that blood proteins denature, or "fold," to form an extended structure with interactions known as "beta sheets" that hold the material tightly together.
“This concept is literally chilling,” explained Dr. Roberts.