Stand by to start space mining – not on an asteroid, but aboard the International Space Station (ISS). Delivered to the station by an unmanned Dragon cargo ship on July 27, an experimental mining kit developed by a team led by the University of Edinburgh will use bacteria to study how microorganisms can be used to extract minerals and metals from rocks on asteroids, moons, and planets.
Mining asteroids has an economic potential that's so great that it may one day force lexicographers to come up with a new word for rich, but setting up operations takes a lot more than just showing up in a space suit with a pick axe. As on Earth, extracting metals and minerals often requires a complex series of processes that turn ores into a useful material.
One way to do this is a technique called biomining, which uses microorganisms or fungi to act as tiny chemical factories to break down rocks and draw out elements like iron, copper, zinc, gold, uranium, and thorium. First used experimentally in the 1950s, today, it's not only widely used in mining, but also as a way to reclaim areas that have been contaminated by toxic heavy metals.
To apply this principle to space mining, astrobiologists from the UK Centre for Astrobiology at the University of Edinburgh spent the past decade building 18 matchbox-sized biomining reactors that are now aboard the ISS. Inside these, astronauts will place bits of basaltic rock similar to those found on the Moon and Mars, which will be immersed in a solution of bacteria and nutrients.
The goal is to see how well the bacteria work in zero gravity to extract minerals. As the microbes grow, the experiment will monitor how they form colonies and biofilms, which will be analyzed back on Earth at Edinburgh and Stanford University. These biofilms will not only help to develop space biomining, but also provide a better understanding of how microbes grow back on Earth.
"Microbes are everywhere, and this experiment is giving us new ideas about how they grow on surfaces and how we might use them to explore space," says Rosa Santomartino of the University of Edinburgh's School of Physics and Astronomy.
Source: University of Edinburgh
