Asteroid mining has often been portrayed as a potential gold rush, with astronomical valuations like $10 quintillion attached to metallic asteroids such as Psyche. However, a recent paper funded by asteroid mining startup AstroForge and authored by a professor from the Colorado School of Mines’ Space Resources Program provides a more grounded perspective on the real value of asteroid resources.
The study highlights that metals on asteroids fall into two distinct categories: those worth returning to Earth and those better suited for in-space use. Platinum-group metals (PGMs), like platinum and rhodium, stand out as the only economically viable materials to bring back to Earth due to their scarcity, high value, and technological importance. Conversely, common metals like iron, aluminum, and magnesium, while not cost-effective to transport back, could prove invaluable for constructing space infrastructure, such as solar power stations or habitats.
Revisiting the Psyche Hype
The assumption that asteroids like Psyche are composed of “pure metal” is increasingly seen as unrealistic. Instead, most asteroids are likely to contain mixed materials, with potentially lower but still significant concentrations of valuable metals. Recent meteorite studies, which serve as analogs for asteroids, reveal that even less metal-rich asteroids may hold economically extractable quantities of PGMs.
A key discovery is the presence of refractory metal nuggets (RMNs) in certain asteroids, particularly L-type asteroids. These rare celestial bodies may have up to 30% calcium aluminum inclusions (CAIs), structures rich in PGMs. While RMNs boast higher concentrations of PGMs than terrestrial sources, their microscopic size presents significant extraction challenges.
Mining common metals for in-space use faces its own hurdles, particularly in processing them from their oxidized forms. Techniques like molten regolith electrolysis require substantial energy, but building the necessary power infrastructure in space would demand the very materials these processes aim to produce.
AstroForge, the company behind the study, aims to tackle these challenges head-on. With a mission planned for January to survey near-Earth metallic asteroids, the company hopes to refine our understanding of asteroid compositions and their economic viability. While the $10 quintillion figure may be far-fetched, asteroid mining holds promise for the future of space exploration and industry.
By addressing the technical and economic hurdles one step at a time, companies like AstroForge are bringing asteroid mining closer to reality.
