Earlier this week, the reality of asteroid mining came a step closer when President Obama signed into law the Space Act of 2015, which includes in it provisions that allow U.S. companies to mine asteroids and profit from the materials garnered from them. Many are lauding this as an important step in the future of space exploration – others are less enthusiastic.
Why was this necessary?
Two previous treaties/agreements, the Outer Space Treaty of 1967 and the Moon Agreement of 1979, actually prevented commercialization of ‘celestial bodies.’ Some are calling this new legislation a travesty – and I’m just not sure why. Essentially they say that our home, Earth, which weighs in at .00003% of all the mass in the solar system, should be the only place where we can mine for natural resources. In essence we should deplete and pollute our home first. Sorry, but that just doesn’t make sense to me. Anyway, the point is moot. The legislation is now law.
Rather than getting embroiled of the politics of it all, I want to discuss asteroid mining and why it makes sense. I’m a sucker for the Discovery Channel show, Gold Rush, so let’s use gold mining as an example.
The Earth was formed by celestial debris (asteroids) coalescing into a planet. About 99% of all gold on Earth is deep in its core, drawn there during planetary formation by gravitational forces which naturally pull heavier elements inward. So the vast majority of all that gold and other valuable heavier metals was taken out of our reach very early on – but there are a lot of asteroids out there that didn’t form into a planet, and the thought is that most still have all those valuable minerals that their siblings contributed to Earth billions of years ago. In fact, much of the gold that’s near the surface of the Earth is thought to have been deposited by asteroid/meteor impacts. Looking at asteroids in our solar system is like looking at the Klondike – we know the riches are there, we just have to find them and get them out.
Step 1: Prospecting
Gold miners don’t just drop stakes in the ground and start digging, they go out and prospect (or let someone else do it and buy the claim). Asteroid mining is essentially the same. A company called Deep Space Industries has designed briefcase sized prospecting spacecraft that will intercept near-Earth asteroids and perform spectral analysis to determine if each is viable for mining. On the last episode of Gold Rush, the Hoffman crew went on a prospecting mission to El Dorado creek. They were sure they’d find gold, but when they brought back a sample, there was none. What would have happened had they packed up their entire operation, moved it to El Dorado creek, then started mining – only to come up empty? Now think about the expense of doing the same with an asteroid millions of miles from Earth.
Step 2: Get the ‘Pay’
On Gold Rush, the gold-rich pay dirt, or pay, is typically under a layer of what is called over-burden, or relatively worthless soil. The crews must clear that before extracting the pay dirt and delivering it to the wash plant. They use bulldozers to clear, then dig pay out of the ground using excavators. Then they load it in trucks and drive it to where it needs to be processed. On asteroids, there is no over-burden. On Earth, over-burden represents layers of dirt fallen in place after the gold was deposited. Asteroids don’t have that problem – any ‘dirt’ is celestial material and likely rich in resources. Okay, so you don’t need to clear before you excavate, but how do you get an excavator out there to do the dirty work? Deep Space Industries is banking on the loose rocks and debris sitting on the asteroid’s surface. They plan to send harvesting spacecraft to successfully prospected asteroids, land them, then scoop up surface material and return it for processing. They even plan on using water ‘mined’ on asteroids to produce hydrogen to fuel the trip back.
Step 3: Process the ‘Pay’
Back to Gold Rush – all the mining operations take the pay dirt and process it through their wash plants. What they are doing is separating the valuable gold from the worthless rocks, sand and dirt that surrounds it. For asteroid mining, the “wash plant” is a space-based processing facility that extracts all the viable resources from the material – pay dirt – brought back.
So now you’ve got all this great, valuable material up in space. How do you get it back down to Earth? For most of it, the answer is you don’t. It’s expensive to get materials off Earth and up into space, why mine in space just to bring it back down again? One of the benefits of asteroid mining is saving the launch expense for much of what you may need in space. One of the more important materials for this is water. Asteroids tend to be packed full of it in the form of ice. Water can be broken down into oxygen and hydrogen to provide fuel and oxidizer for engines. One of the most “expensive” parts of space missions is getting fuel into space. If we could just launch the spacecraft and fuel it in orbit, then we can dramatically lower the cost of the mission. Utilizing in-space processed materials for resupply and repair/refit means spacecraft can be designed with less redundancy and will live longer operational lives.
Considering the first asteroid and comet encounters, such as the Deep Impact mission depicted in the main image of this post, only recently successfully completed their intercepts, it will likely be years before the first prospecting missions get off the ground and they will likely take time to perfect. NASA’s Asteroid Redirect Mission isn’t due to analyze its asteroid until the mid-2020s. Still, billions of dollars are being invested into this industry and this latest legislation being signed into law will only open the spigot for more to flow in.
I’m not sure that asteroid mining is something that will take off in the near future, but it surely will happen. Companies like Deep Space Industries and another in the business, Planetary Resources, are getting a head start on the competition. It will be interesting to see how this plays out in the coming years.
Photo credit: NASA/JPL