Context: Recently, Researchers from the Indian Space Research Organisation (ISRO) and the Indian Institute of Science (IISc) have developed a way to make bricks from Martian soil with the help of bacteria and urea.
Space Bricks

• ISRO and IISc have collaborated to develop a novel scalable technique of manufacturing space bricks using Martian Simulant Soil (MSS).
• The team first made the slurry by mixing Martian soil with guar gum, a bacterium called Sporosarcina pasteurii, urea and nickel chloride (NiCl2).
• This slurry can be poured into moulds of any desired shape, and over a few days the bacteria convert the urea into crystals of calcium carbonate.
• These crystals, along with biopolymers secreted by the microbes act as cement holding the soil particles together.
• This method ensures that the bricks are less porous, which was a problem with other methods used to make Martian bricks.
• The bacteria seep deep into the pore spaces, using their own proteins to bind the particles together, decreasing porosity and leading to stronger bricks.

Their significance

• In the past, the team had made bricks out of lunar soil using a similar method.
• These ‘space bricks’ can be used to construct building-like structures on Mars that could facilitate human settlement on the red planet.