Magnets and drill swarms: ways to mine an asteroid

This is a comet, but it's very cool anyway. (Image: CC)

Planetary Resources, one of the premier researchers of commercial deep space exploration, has highlighted potential methods to mine asteroids in future.

Asteroids are high in valuable mineral content, and there are over 16,000 near-Earth asteroids that could contain a wealth of resources. Asteroids are considered extremely difficult to land on; in 2014 the European Space Agency’s Rosetta probe managed to land on a comet, but generally the gravitational pull of asteroids is too small for large landings.

As such, the company has theorised the possibility of using mining bot swarms for material collection from C-type (water holding) asteroids using proboscis-like drills. The drills could collect underwater soil and then heat it using a processor.

For metal-heavy asteroids, primarily S-type asteroids, it has been theorised that magnets could be used in lieu of drills, so high is the concentration of metals in the regolith of certain asteroids.

“You have to wonder whether you could just bring the whole thing back,” said Professor John Lewis of the University of Arizona.

Early technological escapades could prove hugely expensive – NASA last year launched its $US1 billion ($1.3 billion) OSIRIS-REx mission, which will take two years to reach the asteroid Bennu in order to collect small samples of ‘carbonaceous regolith’. However, the expenses could be justified by the rewards; the most lucrative known asteroid is a large 160 kilometre-wide B-type asteroid (a subset of the C-type), 241 Germania, which has been theorised as containing a mineral wealth of up to $US96 trillion ($126.5 trillion).

Planetary Resources’ exploration program is expected to begin in 2020.