Space Mining

Rockets, Robots and Platinum-Studded Asteroids

By | Updated Aug 28, 2015 6:57 AM UTC

Swirling through the cosmos, within striking distance of Earth, are thousands of extraordinarily valuable rocks. At least, that’s the theory: Asteroids, known to science since 1801, have of late become the object of a minor boom in speculative investment. At least two companies plan to mine near-earth asteroids for precious metals, and many scientists think their resources could be instrumental in future spacefaring. Yet who would rightfully own this celestial abundance isn’t a settled question under international law. And plenty of skeptics think the whole pursuit is daft.

The Situation

In August 2015, the number of near-earth asteroids identified topped 13,000, with an average of three more being confirmed every day. The month before, a spacecraft built by Planetary Resources took off from the International Space Station on a mission to test the instruments and software needed for a robotic mining expedition. Many asteroids are rich in water and precious metals, notably platinum, a prime ingredient in everything from catalytic converters to cell phones. NASA is planning its own mission in 2016 to visit an asteroid and bring some of its surface material back home. The U.S. Congress is mulling legislation that would confer property rights on companies that extract extraterrestrial resources. And the U.S. Federal Aviation Administration, which regulates some private space activity, has been quietly encouraging aerospace companies that want to commercialize the cosmos. Peter Diamandis, a co-founder of Planetary Resources, estimates that a single asteroid 30 meters in diameter could yield $50 billion of platinum, and there are thousands that are larger. In 10 years, the company — which counts Eric Schmidt and Larry Page of Google among its financial backers — hopes to have produced its first liter of extraterrestrial water. Deep Space Industries, a competitor, says it plans to use 3-D printing to build a zero-gravity manufacturing plant. In space, as in Silicon Valley, hyperbole is not unknown.

The Background

Asteroid mining is a fairly old idea. The Russian physicist Konstantin Tsiolkovsky proposed something similar in 1903, as part of a plan for human development of space. More than a century of science fiction, from Jules Verne to Antoine de Saint-Exupery, expressed variations on the idea. As the Space Age dawned in the 1960s, asteroid mining gained more real-world adherents (Lyndon Johnson was reportedly an enthusiast) and scientists proposed a series of mining schemes, practical and otherwise. More recently — as propulsion technology has improved, satellite components have grown cheaper and asteroid research has progressed — commercial mining has inched closer to reality. In the near term, it may have larger scientific benefits than economic ones, by making human space travel more feasible: The water on asteroids could theoretically be used as a propellant (when split into hydrogen and oxygen), as shielding (to absorb cosmic radiation), for hydration (you probably don’t want to be the first to try this) or to fuel communications satellites.

The Argument

By some approximations, all this adds up to a trillion-dollar industry in the making. By others, it adds up to a galactic delusion. A recent study by a Harvard University astrophysicist concluded that a grand total of 10 near-Earth asteroids would be worth even trying to mine: Most are either too small, too far away or too barren to make the mission economically feasible. The mining companies, unsurprisingly, dispute that estimate. Other obstacles abound: Asteroids have variable surface conditions, unstable interiors and negligible gravity, which means mining them will require some novel technology. Bringing back huge amounts of platinum could drive its market price down, likely limiting potential profits. And it all may well be illegal: Relevant international treaties clearly prohibit the appropriation of territory in outer space, but they aren’t very clear about the legality of extracting natural resources or the ownership status of any valuables dredged up. That’s one question, among many, that still requires an earthly answer.

The Reference Shelf

  • A Bloomberg View editorial argued that new guidelines for commercial space activity would help reassure asteroid-mining investors.
  • NASA helpfully tracks asteroids near Earth.
  • The Keck Institute for Space Studies published a report on the feasibility of retrieving an asteroid.
  • Popular Mechanics explains the nuts and bolts of mining.
  • The Outer Space Treaty of 1967 lays out the principles governing international space law.
  • Matt Novak of the BBC investigated past attempts to mine asteroids.

First published Aug. 27, 2015

To contact the writer of this QuickTake:
Timothy Lavin in Hong Kong at

To contact the editor responsible for this QuickTake:
John O'Neil at