BENGALURU: This wont be just another brick in the wall. In what holds potential of aiding construction of future settlements on Moon, a team of Indian Institute of Science (IISc) and Isro researchers has developed “space bricks” using Lunar Soil Simulant (LSS).
The team led by Aloke Kumar, an assistant professor from the mechanical engineering department at IISc, took up the research on manufacturing bricks using LSS given that prospects of in situ resource utilisation — using local resources available on Moon — have gained favour for proposed habitat projects on Moon planned by different agencies around the world.
They used LSS developed by Isro for the purpose. And, as reported first by TOI in February 2018, Isro has mastered the process of creating LSS whose properties match 99.6% with the samples brought back from Moon by the Apollo missions.
Also, a futuristic project of building Igloos on Moon is already underway in Isro, but it is yet to be officially budgeted. The space agency has more than 60 tonnes of LSS lying with it.
“The name (space brick) itself conveys an idea of settlements outside Earth. We started working on this about two-and-a-half years ago, trying to answer one question: Can we make bricks out of lunar soil? We began working on the process, and today, weve manufactured bricks in our lab,” Kumar told TOI.
Kumar said they used “bacterial growth induced biocementation technology” to manufacture bricks. They wanted to organically grow bricks and therefore chose bacteria and tried a process called “microbial induced calcite precipitation”, wherein, in the right conditions, the bacteria can precipitate calcium carbonate.
Now, heres what all this means in laymans terms: Bacteria are very versatile and certain species are capable of bio-mineralisation — process by which living organisms produce minerals to harden or stiffen existing tissues — which was done to make this brick.
So, the team used one specific bacteria (Sporosarcina pasteurii), which was introduced into LSS, which then hardened. “In perfect condition, the LSS, which is a powder, slowly turns into a brick after 15-20 days of introducing the bacteria,” Kumar explained.
However, the first set of bricks lacked strength and could be broken with bare hands. “We then used guar gum, a naturally occurring polymer, as an additive. The results were fantastic and the brick exhibited an approximate 10-fold increase in strength,” Kumar said.
Guar gum, extracted from guar beans has thickening and stabilizing properties useful in food, feed, and industrial applications.
On whether, this bacteria can function in the same manner in the lunar environment, Kumar said: “All organisms change their behaviour in varying conditions. Therefore, in order toRead More – Source