Astrobiologists have proposed extracting valuable elements from the rocks of the Moon and Mars using extremophile bacteria. Scientists have successfully tested their method on board the ISS.
We are talking about rare earth elements (REE) and their compounds. They possess unique magnetic and catalytic properties and, importantly, are essential components of electronics and industrial equipment. They will be needed when exploring other planets, but it will be difficult to deliver them from Earth.
We have shown that bacterial mining is feasible throughout the solar system. It will be unprofitable to transport them to Earth, but thanks to a similar technique, it will be possible to create autonomous colonies in space. For example, bacteria and robots can be sent to extract resources in the Ocean of Storms on the Moon, where rocks rich in rare earth metals are found.
Charles Cockell, one of the study authors, professor at the University of Edinburgh in the UK
On Earth, microorganisms are regularly used to extract gold and copper from rocks. This is the so-called bio-extraction method. Scientists decided to test how it would work in the absence of gravity.
The group has created what are called bioprospecting reactors. These are such small devices that maintain conditions typical of the Moon and Mars. The researchers conducted a series of experiments onboard the ISS called BioRock: scientists sent several test tubes filled with basalt and cultures of three types of similar bacteria to the station – Sphingomonas desiccabilis, Bacillus subtilis and Cupriavidus metallidurans.
Zero gravity conditions negatively affected only one type of bacteria. The rest continued to extract rare earth and heavy metals from the rock.
The authors believe that bacteria in space can be used not only for mining, but also for decomposing rocks to form soil and then growing crops on it or to provide the necessary mineral raw materials for systems that produce air and water.