The PHASTT Network

Denis Scot / CORBIS

Lately, asteroids have been getting a lot of press. Especially the potentially hazardous ones. It makes sense because the threat is very real with potential consequences far greater than any other natural disaster that we can think of (apart from maybe when the Sun turns into a red giant). But is that the only reason that we’re hearing about these rocks as they go zinging by the Earth? Probably not. As it turns out, there is also a monetary interest in near-Earth asteroids. The exploitation of near-Earth resources could be big money some day. So much so, that at least two companies are betting on it.

With more than 10,000 near-Earth objects greater than 140m in diameter already known and, potentially, more than a million greater than 50m in size, asteroid miners of the future will have no shortage of resources to chase. Technologies are being developed today to make resource extraction possible and it is quite likely that a PHASTT-like network will be instrumental in the discovery and characterization of some of these resources.

But what is the magnitude of resources that we’re talking about here? Let’s say, for example, that we’ve just found a small asteroid that is about 150m in diameter with 1% water. And let’s say, for the moment, that we can get to it relatively easily and that we have the technology to extract the water from it. What would that water be worth to us? Well, as a very rough estimate, we calculate the volume of water to be about 140,000,000 litres. On Earth, this would be about 280,000,000 or so Perrier dollars. A lot of dosh to be sure, but, how much would it cost to put those 140,000,000 litres into space? With launch costs somewhere between $2,200/kg to low-Earth orbit (Falcon Heavy) and $27,000/kg to geostationary transfer orbit (Atlas V) we’d be looking at something between $300 billion and about $3.8 trillion. So we can start to understand how it might make sense to extract water from an asteroid in space if it just happens to be close to where we need it, when we need it. Of course, there is a cost associated with the actual mission and you wouldn’t get 100% recovery but, still, there’s probably still a profit to be found…

So, near-Earth asteroids are of interest both because they could, one-day, hit the Earth (doing a lot of damage when they do) and they can make a ‘shed-load’ of money for those investing in the asteroid mining business. Although, I’d like to think that it’s the threat of impact that piques our interest, I suspect that it’s the prospect of asteroid exploration that will really capture our imaginations in the future.