IISc Bengaluru team finds bacteria-based method to fix Moon bricks

IISc’s Brick-Repairing Bacteria May Help Build Lunar Homes.

Picture using living microbes to restore homes on the moon. Indian researchers are now exploring just that for future space missions.

Researchers at the Indian Institute of Science (IISc) have come up with a bacteria-based method to fix lunar bricks. It could be helpful in building or maintaining habitats on the harsh conditions of the moon.

Bricks and Bacteria: An Unlikely Couple

The bacteria, Sporosarcina pasteurii, employs calcium and urea to form calcium carbonate crystals. The crystals hold lunar soil particles together when combined with guar gum. The result? cost-effective and environmentally friendly brick-like structures.
IISc's mechanical engineering department applied this technique to Martian and lunar soil simulants a couple of years ago. Their goal was to make bricks without cement, which is difficult to transport to space.

They also tried sintering, another process. It involves heating the temperature of a mixture of soil and polymer. This process yields stronger bricks suitable for building homes.

According to Prof. Aloke Kumar, "sintered bricks have very high strength." "They can easily support loads associated with conventional housing."

But the Moon Isn’t Easy on Buildings

Compared to Earth, the lunar environment is much more harsh. In a single day, temperatures can range from 121°C to -133°C. In addition, there is continuous exposure to meteorites and solar radiation.

IISc scientists reactivated their bacterial technique to solve this. They used a slurry mixture and created simulated fissures in the sintered bricks. This consisted of lunar soil simulant, guar gum, and microbes.

Prof. Kumar said, "Initially, we did not think it would work." "But the bacteria hardened the mixture and retained it well."

Between 100°C and 175°C, the bricks that were restored were intact. Even when subjected to stress, they showed enhanced bonding and strength.

Next Action: Space Testing

The team's next aim is to test the bacterium in microgravity. A plan to send samples on India's upcoming Gaganyaan mission is being readied. Prof. Kumar said, "We want to see how the bacteria behave in space."

If successful, this method could assist NASA's Artemis and other long-duration lunar missions. Costs could be significantly minimized through the utilization of native lunar soil instead of hauling heavy materials from Earth.

Lunar homes could soon be more than science fiction with the help of microorganisms, nature's smallest engineers.

(Inputs from PTI)