Chapter 1: Microbial Astronauts and Their Potential

Microbial life forms may play a crucial role in ensuring life persists on our planet.

Photo by Manouchehr Hejazi | Unsplash

If you’ve delved into James S. A. Corey’s ‘The Expanse’ series, either through the books or the television adaptation, you’re familiar with a future where humanity has extended its reach across the solar system. The inhabitants known as the ‘Belters,’ residing in the asteroid belt, engage in mining for essential resources. The reduced gravity experienced on these celestial bodies results in unique physical adaptations among the Belters, who develop elongated limbs and fragile bones. As Kevin Fong notes, environments with low gravity, like those on Mars, lead to a condition akin to ‘space-flight-induced osteoporosis,’ among various other detrimental health effects related to long-duration space travel.

One thing is clear: life as a Belter presents significant challenges.

The Escalating Demand for Rare Earth Elements

In our current reality, the need for rare earth elements (REEs) is on the rise. These crucial elements are integral to the production of electronics, alloys, and magnets, such as neodymium. As our dependence on technology increases, so does our reliance on REEs. Although these elements are not particularly scarce on Earth, they are seldom found in high concentrations, making commercial extraction challenging.

A method known as ‘bioleaching’—a specialized form of biomining—utilizes specific bacterial species to extract metals from ores. This technique alleviates many of the difficulties associated with conventional mining. The bacteria facilitate the extraction of metals, producing a liquid known as leachate that concentrates the REEs into a more accessible form. Biomining holds significant promise for the economically viable recovery of metals, especially from ores that are of lower grades.

Ultrapure neodymium under argon, 5 grams. Original size in cm: 1 | By Unknown author — http://images-of-elements.com/ | CC BY 1.0

Despite the assistance of these microorganisms, further exploration for REE deposits may be necessary, particularly on asteroids, moons, and other planetary bodies.

Can Microbes Operate in Space?

The findings from Cockell et al. (2020) indicate a resounding ‘yes.’ Their research involved sending specially chosen bacterial species to the International Space Station to investigate their capability to mine basaltic rock under two distinct gravity conditions: microgravity and simulated Martian gravity. The basaltic rock was selected for its resemblance to the types of rocks found on the Moon and Mars. Surprisingly, the study revealed no significant differences in the bacteria's mining capabilities between lower gravity environments and Earth.

This research builds on earlier experiments conducted aboard the International Space Station, demonstrating that various microbial species can thrive in space. For instance, Deinococcus radiodurans has been shown to endure the vacuum of space and the harsh radiation for up to three years.

Microbes = 1, Humans = 0.

What Lies Ahead for Microbial Mining in Space?

Cockell et al. employed a miniaturized reactor in their experiments.

1. Experimental container with culture chamber and medium, b) Cross-section of culture chamber, c) Basalt slide in a petri dish, d) Luca Parmitano, an astronaut for the European Space Agency (ESA), carefully placing the experimental container into the incubator onboard the International Space Station (Credit: ESA) | Cockell et al., 2020 | CC BY 4.0

According to the authors, the subsequent step involves scaling up and refining the technique. KREEP rocks, found on the lunar surface, are rich in potassium (K), phosphorus (P), and notably, REEs. Given that the Moon’s gravitational pull is intermediate between microgravity and that of Mars, it presents a promising target for future mining endeavors, particularly in KREEP-rich areas like Oceanus Procellarum and Mare Imbrium.

Image of the Oceanus Procellarum and Mare Imbrium (darker areas) | By NASA (mosaic of images by Lunar Reconnaissance Orbiter), Public domain, via Wikimedia Commons.

It may sound fantastical to suggest that microbial astronauts could be pivotal in sustaining life on Earth. Yet, as Mark Twain aptly stated, ‘Truth is stranger than fiction […]’.

Future Perspectives on Microbial Mining

As we look ahead, the integration of microbial technology in space exploration could redefine our approach to resource extraction beyond our planet.

The first video titled "Using Microbes to Mine Mars: The Future of Biomining" delves into the potential of microbial techniques in extraterrestrial mining, revealing how these organisms could revolutionize resource acquisition in space.

The second video, "Microbes Study on Space Station for Future Biomining on the Moon, Mars," explores ongoing research examining how microbes can thrive and be utilized in future lunar and Martian mining missions.