ISRO-IISc develop 'space bricks' for habitat construction on Moon and Mars

In a major leap toward planetary exploration, scientists from the Indian Space Research Organisation (ISRO) and Bengaluru’s Indian Institute of Science (IISc) have developed a sustainable process to make ‘space bricks’. If successful, the process would allow the construction of habitats on the Moon and eventually on Mars. In a special report, IISc revealed that the method uses bacteria and guar beans and exploits the lunar and Martian soil to consolidate the content into tough, load-bearing brick-like structures.

Indian scientists find ways for lunar & Martian habitation

(Martian brick sample; Image: IISC)

Aloke Kumar, Assistant Professor in the Department of Mechanical Engineering, IISc said in the university’s statement, “It is really exciting because it brings two different fields — biology and mechanical engineering — together”. The scientists argue that the use of such methods is important because space exploration has grown exponentially and these ideas would help in settling humans on other planets while Earth’s resources continue to dwindle. 

Talking about the process of 'space brick' manufacturing, IISc revealed that the raw material required for manufacturing the bricks are urea— which can be sourced from human urine — and lunar soil. The team of scientists created brick samples for habitats on both Mars and Moon by using soil simulants mixed with guar gum, a bacterium called Sporosarcina pasteurii, urea and nickel chloride. IISc explained that once combined, the resulting content can be poured into moulds of desired shape. In the next step, the bacteria used in the mixture would convert the urea into calcium carbonate crystals after a few days. These microbes then secrete biopolymers that act as cement which holds the soil particles together. 

(Lunar brick sample; Image: IISC)

Koushik Viswanathan, a professor at IISc revealed that "Martian soil contains a lot of iron, which causes toxicity to organisms. In the beginning, our bacteria did not grow at all. Adding nickel chloride was the key step in making the soil hospitable to the bacteria". Meanwhile, the scientists are planning to investigate the effect of Martian atmosphere and low gravity on the durability of the 'space bricks'. Another problem is ensuring thriving conditions for the bacteria as they cannot survive in the Martian atmosphere that is 100 times thinner than the Earth’s and contains over 95% carbon dioxide.

To tackle this problem, they have created a device called MARS (Martian AtmospheRe Simulator), that can create atmospheric conditions similar to Mars inside a lab. In addition to this, the scientists have also created a lab-on-a-chip device that aims to measure bacterial activity in micro-gravity conditions. Interestingly, these devices will soon be sent into space with ISRO's help to study bacterial growth in low gravity. 

Image: IISc