Corporations are discussing asteroid mining again. You may not have noticed, but last November President Obama signed a law establishing mineral rights for asteroid mining. It seems inevitable that, as human population continues to explode, demand for raw materials will explode with it, driving corporations and nations to search space – first the moon and then the asteroid belt – for additional resources. This suggests a scenario that, due to human mistakes or terrorist action, could create an extinction event that could wipe out all or most life on the planet, similar to the event that “did in” the dinosaurs and almost all life on the planet. So how could such a disaster could occur?
Human population growth is still going up like a rocket though it has shown signs of slowing slightly in the past decade. It seems inevitable that the demands of our exploding population will exhaust the earth’s resources, one by one, and drive resource extraction companies to mine the asteroids, and it is no secret that they are already working on this. First, possibly in the next decade, one or more companies will launch their own missions to do prospecting on the moon. Since not much of value is expected there, based on past exploratory missions, they will reach for the asteroids soon after that.
At first asteroids will be mined slowly and at astronomical cost, mostly as a proof of concept and to establish feasibility. Carrying the output of asteroid mines back to Earth in ships will be prohibitively costly, both due to the cost of the ships and propellant but also due to the small quantities that could be brought back. Asteroid mining has been discussed for decades, and companies like Planetary Resources have been looking for ways to move higher volumes of material back to Earth at lower cost. One of the ideas that has long been considered is to use a “rail gun”, a magnetic linear accelerator, to propel streams of chunks of raw material towards Earth where they would have to be caught and then transferred down from orbit. Many expect this to be the best option once asteroid miners begins to operate commercially.
What if a projectile hits the Earth? There is risk, of course, that a chunk of material in the stream would accidentally be deflected off its route and hit the earth as a meteor. Perhaps that would occur fairly often, especially at first, but with the chunks being basketball sized or smaller they would burn up on entry and never near the ground. As long as they didn’t hit a satellite or high flying airplane they would provide little more than a light show in the sky, and the odds of hitting anything would be astronomically small.
Increasing efficiency could eventually involve moving whole asteroids. Companies always work to improve what they do and reduce their cost, so it is likely that soon companies would be lobbying (would they need to ask anyone’s permission?) for permission to shoot larger and larger chunks back to earth. Eventually one of them would want to move an entire asteroid back to Earth, probably to park it in an orbit from which it can be mined much more cheaply. And if that is successful then other companies will follow and there will be more and more moved until the Earth could be surrounded by many small asteroids in orbit. Could an asteroid’s orbit decay until it falls to Earth?
Complex systems designed and governed by humans always develop problems. Once such a system is in place, sooner or later, something will go wrong, a number of human errors will compound, or someone will lose their mind, and an asteroid or really large chunk of material will get out of control or be aimed wrong, and it will endanger the Earth. This could occur as a result of terrorist action or simple compounded human errors. If an asteroid a quarter mile across or larger should end up hitting the Earth, as happened millions of years ago, it could wipe out more than 97% of all species on earth, leaving behind a planet with the kind of pollution and ecological destruction we see more and more today, only thousands of times more severe. Life on the planet could be completely disrupted and quite possibly wiped out by years of “nuclear winter” and the effects of the incredible impact, blast, and rain of fire that would extend over part or all of the globe.
Humans equal risk. The risk, clearly, is of having an extinction event resulting from corporate asteroid mining. Asteroid mining seems inevitable given the demands of the population explosion, and this suggests an asteroid mining accident is also inevitable. Given the risk of both mistakes and the possibility that no government will be able to regulate the practice or prevent a dangerous event, is there any way to avoid calamitous outcomes? I don’t know the answer to that, but I do know that, through this or a similar chain of events, the population explosion could create circumstances under which a human-caused extinction event could result. If, however, our population growth rate can be reduced to unity soon enough, and the population can be brought under control before we run out of terrestrial resources, humanity might be able to avoid causing an extinction event. We can only hope.
Thanks for reading. — Tim
Planetary Resources, Inc.