As we reported last week, several tech billionaires have teamed up to back a new company called Planetary Resources, with the goal of identifying and then mining near-Earth asteroids for valuable minerals. The company is founded by Eric Anderson and Peter Diamandis, the latter of whom started the X Prize foundation to incentivize private space-faring rocket research. Other backers of the project include Google's Larry Page and Eric Schmidt, and James Cameron has a seat on the company's advisory committee.
The strategy for mining asteroids, as explained by Anderson, has three parts, each with unique technical challenges. First, they have to identify which of the near-Earth asteroids would be ideal for mining. Some of this job has already been done by astronomers and astrophysicists, who have cataloged over 7,000 (out of the estimated 9,000) near-Earth objects--partly to assess impact risk and "killer asteroid" potential. Of these objects, only about a thousand are larger than 1km in diameter, and lie within a wide range of spectral types. Planetary Resources will use Earth-based sensors and satellite-telescopes like WISE to infer the composition of these asteroids, which they hope will yield rare minerals or water. In fact, the current plan is to launch a telescope in 24 months to find asteroids suitable for mining before the end of the decade.
The next phase will be the most difficult, as it involves not only accessing the asteroids with in-development rocket technology, but creating robots that can effectively mine the target asteroids efficiently. Unlike mining on Earth, mineral deposits on asteroids may be spread throughout the object's body, so robot can't just dig in one place and load platinum into cargo load. The mining robots have to be cost-effective enough to justify the expenditure, too. Planetary Resources estimates that its costs will range in the tens of millions per launch, as opposed to the hundreds of millions NASA spent to launch each Space Shuttle mission. It also does not plan on sending any humans for mining--Anderson's Space Adventures business is still the place for aspiring space tourists to contact.
Finally, Planetary Resources has to develop the ability to return those harvested minerals back to Earth, again, cost-effectively to make the trip worthwhile. One of the more exciting prospects of asteroid mining is that we might not even want to bring harvested materials back--metals like iron, nickel, and aluminum can collected in space to use in construction habitats, spacecraft, or shielding. Water is another potential resource that would be incredibly valuable to collect. Having stores of water in space for consumption and oxygen production would make future long-term space programs much more affordable.
Skeptics of the program don't see the practicality of spending billions to mine asteroids when other areas of space exploration haven't reached a point where mining's benefits could be fully utilized. Aside from the International Space Station, we don't have long-term space habitats yet, nor have we developed the technology to use space-based resources for construction. Reaching an asteroid with a man-made craft is absolutely possible--we've done it several times before--but the only time we have ever retrieved sample material back from an asteroid was Japan's Hayabusa mission, and that was only for a few dust particles, not tons of rare metals.
Still, Anderson and Diamandis, along with their high-profile supporters, are optimistic about the economic benefits of the enterprise. The Platinum-group metals that they seek, including palladium, iridium, and platinum, are used heavily in computing, electronics, and automotive industries. While we're not short on any of these materials on Earth, they are still rare and expensive--about 200,000kg of Platinum and Palladium was each mined in 2011, with most coming from South Africa. Having more access and control of these minerals could be lucrative, but Planetary Resources also wants to drive their prices down, much like how the commodification of aluminum in the late 1800s affected industry. Planetary Resources is calling the space economy a trillion-dollar industry, and they're willing to invest billions to tap into it. Asteroid mining may indeed be the next gold rush, but as of now, the people behind Planetary Resources are the only ones reaching out to this new frontier. And even space mining yields no tangible mineral rewards, all of us Earth-side will undoubtedly benefit from the research and technology developed for the endeavor. If there's one thing we've learned from NASA, science is often best furthered as a side-benefit of other goals, whether they be military or economic.