One of the most frequent questions I get is regarding how and where asteroid mining will happen. As in golf, asteroid miners “will play it as it lays.”
Starting with the water-rich carbonaceous asteroids, every precious liter of water will be extracted and purified on-site, right in the same orbit around the Sun that asteroid has been in for millions of years. Asteroid mining will make use of the abundant and free thermal energy from our Sun, the vacuum of space for vapor transport, and the cold dark sky to vaporize, purify and collect this material which costs 10s of millions per ton to launch into space.
As we have discussed before, in space everything comes down to how much rocket fuel you need to do a job. It would be a waste of rocket power to bring back anything to the Earth-Moon system that we don’t need. That drives the need to make sure the extraction occurs at the asteroid, far from Earth.
This is actually the same way that traditional mining works. In many cases tons of ore are reduced to mere grams of profitable minerals (sometimes by a mass ratio of a million to one). For many minerals, this is done as close to the mine-site as possible, in order to ensure the greatest profit, and reduce the extreme cost and energy of transporting vast quantities of heavy, useless material (the gangue). For the same transportation cost reasons, mining of asteroids will be motivated to do the same – mine and refine at the source.
NASA’s Asteroid Retrieval Mission (ARM) has perhaps confused the issue, as NASA has chosen to capture and return up to 500 tons of a Near Earth asteroid, and bring it to a distant retrograde storage orbit around the Moon. NASA’s reasons for doing this are different than for us asteroid miners, as they are looking to demonstrate advanced high power propulsion systems, and provide astronauts an interesting destination and research opportunity for growing the capability for human exploration of deep space. While many of the technologies and approaches used in accomplishing this feat will advance the state of the art, this is not how we would propose to mine an asteroid.
Last, even though Bruce Willis and his crew make it look relatively easy in the movies, perturbing the orbit of an asteroid is an extraordinary challenging and precision activity. For the very few asteroids that are on a near-collision course with Earth (see the JPL Sentry Risk Table), its fortunate that only a slight nudge is necessary to avert disaster and protect us Earthlings from the fate of the dinosaurs. For the 1000’s of asteroids minding their own business orbiting the Sun, they will continue to do so even as they are mined for the materials that will open up the Solar System for humanity. As Isaac Newton deduced – “an object in motion stays in motion” – and separating useful material from the rest does not change its orbit.
If life gives you the opportunity to study the fascinating field of celestial mechanics, you’ll get to learn all the incredible and fun physics that keep the Earth orbiting the Sun, day, night and the seasons proceeding according to schedule, and the wonderful dance of the asteroids, comets and planets around the Sun. You’ll be more connected with the universe, and realize how truly blessed we are to have these wonderful resources in our Solar System, just waiting to support our lives and livelihood as we venture off this planet and towards being a multi-planetary species.
-Chris Lewicki. President & Chief Asteroid Miner
Planetary Resources, Inc.