Space Fungus: Mining Asteroids for Precious Metals Like Palladium
Fungus outperforms chemistry in space, extracting metals from meteorites.
Top Summary
- What happened: An experiment on the International Space Station (ISS) showed that the fungus *Penicillium simplicissimum* is highly effective at extracting palladium from meteorite fragments in microgravity.
- Why it matters: This research suggests that biomining, using microorganisms to extract resources, could be crucial for establishing long-term settlements on the Moon, Mars, or in orbiting habitats. It offers a potential alternative to the prohibitively expensive option of shipping materials from Earth.
- What changes for people: This could lead to the development of sustainable resource extraction methods in space, reducing dependence on Earth-based supplies for future space missions and settlements.
- Who is affected: Space agencies, future space settlers, the mining industry, and researchers in astrobiology and biotechnology will all be impacted.
BioAsteroid Experiment: A Giant Leap for Space Mining?
Scientists have demonstrated that fungi can outperform traditional chemical methods in extracting valuable metals from meteorites in space. The BioAsteroid experiment, conducted on the International Space Station (ISS), showed promising results for future space resource utilization.
The experiment involved sending millimeter-sized fragments of an L-chondrite meteorite, originally from northwest Africa, to the ISS aboard a SpaceX Falcon-9 rocket in December 2020. The meteorite pieces were then exposed to two types of microorganisms for 19 days in weightlessness.
Fungus vs. Bacteria in Microgravity
The team, led by Rosa Santomartino at Cornell University and in collaboration with Charles Cockell at the University of Edinburgh, tested a bacterium, *Sphingomonas desiccabilis*, and a fungus, *Penicillium simplicissimum*.
NASA astronaut Michael Scott Hopkins loaded the experiment containers into KUBIK incubators aboard the ISS. The goal was to observe and measure the bioleaching capabilities of each microorganism.
The results revealed that *P. simplicissimum* significantly outperformed the bacterium. In microgravity, the fungus boosted palladium extraction to roughly 550 percent of what non-biological leaching achieved.
Palladium Extraction in Space
The fungus was able to extract nearly 12 percent of the palladium from the meteorite within the 19-day period. It also enhanced the release of ruthenium and platinum.
In contrast, the bacterium performed no better than the sterile control for most platinum group elements and, in some cases, even inhibited leaching. Abiotic palladium leaching plummeted 13.6-fold in microgravity compared with Earth, demonstrating the fungus's vital role.
The Economics of Space Biomining
Although the economics remain challenging, the experiment highlighted the potential of biomining in space. Based on current palladium prices, the team calculated that a fully scaled-up bioleaching operation using their experimental conditions would recover roughly $10 worth of the metal.
However, removing the fungus from the equation would result in a 545 percent economic loss, due to the poor performance of abiotic leaching in microgravity.
Rosa Santomartino said the team wanted to understand the mechanisms at work in space precisely because so little is currently known. "We wanted to keep the approach tailored in a way, but also general to increase its impact," she said, adding that "not much is known about the mechanisms that influence microbial behavior in space."
Future Implications
The experiment serves as a proof of concept, showcasing the potential of biology to overcome limitations in physics and chemistry in low gravity environments. This could pave the way for turning microbes into an essential component of any self-sustaining settlement beyond Earth.
- Asteroids are rich in metals like palladium and platinum.
- Shipping resources from Earth costs roughly tens of thousands of pounds per kilogram to low Earth orbit.
- Biomining already extracts about 20% of the world’s copper on Earth.
What to Watch Next
Future research will focus on understanding the specific mechanisms that influence microbial behavior in space, with the aim of optimizing biomining processes for various space environments. The team also plans to explore the potential of other microorganisms and their synergistic interactions for enhanced resource extraction from asteroids and other extraterrestrial materials.