Ifan Investigates… Asteroid mining

After watching Oxygen I was fascinated by the amount of scientific concepts there was in the episode. Yet a part of me was wondering how much of it was actually accurate, specifically the asteroid mining.

So asteroid mining is particularly self explainable it is the exploitation of raw materials from asteroids and other minor planets. Minerals and volatiles could be mined from an asteroid or spent comet and then used either in the station or be transported back to earth.

Now in Oxygen we see a mining station called Chasm Forge which looks seems to be mining from a nearby asteroid. It’s noted in the episode that they’re mining copper or more specifically copper ore. However, is any of this scientifically accurate?

There are 3 major types of asteroids, C-type, M-type and S-type. These stand for Carbon, Metal(s) and Silicate respectively, there’s also a D-type yet it’s lesser known and less common. Carbonaceous asteroids (C-types) are the most abundant type of asteroid with 75%, then there’s Siliceous asteroids (S-types)with 17% and the majority of the rest are Metallic asteroids (M-types). Now if we want to find copper, the best chance to find it is in a Metallic asteroid as copper is a metal.

A Metallic asteroid is typically 20% nickel and 80% iron (which is why they’re magnetic) however they do sometimes have special cases where they contain other metals such as copper ore. These are more specifically the subtype 1 asteroids of the Metallic type. However as Copper isn’t fused in a star, this asteroid must come from a supernova explosion where fusion can exceed past iron. Copper can be formed in other ways such as molten rock, yet on an asteroid in space, geological processes don’t occur the same. For instance the earth has 4 layers, the inner core, outer core, mantel and lithosphere (crust), however an asteroid doesn’t have these layers. Also, the layers of asteroid can vary a lot due to it’s distance from the sun and as a result of bombardment.

So it’s perfectly possible for an asteroid to have copper, however could the crew on board the space station extract it to get pure copper?

To get copper out of a copper ore you have to heat it with carbon, this seems easy as the station looked like it could easily do it, also carbon is an abundant element (and can be found in a C-type asteroid!) However, the copper is impure, so to pure it you can use electrolysis (this process was mentioned in the episode yet wasn’t used in this context). Knowing this, we know the station is capable of doing electrolysis. So it could’ve easily done electrolysis to get pure copper.

However, does this method make sense? Is it economically well thought out?

Well first thing first, we must consider how much copper is in an asteroid, it’s a very small percentage overall and it’s only in one subtype (1) of a major type (M). Also, the asteroid must’ve been formed by a supernova which occurs about 3 times every century. This means not only that the chances of finding a copper asteroid is low, but the percentage of copper in that asteroid is also low. Yet, this could work as copper is something that runs out it’s not renewable (excluding recycling), once it’s gone it’s gone, this means that maybe copper was very scarce and finding a little bit could be profitable. This is all to do with supply and demand, if the supply is low, the demand is high and even a little bit will help, also the price of copper would greatly increase. Also the cost of space travel would be far lower, meaning that this strategy could work. This also perhaps explains the ruthlessness of the cooperate dominance in the episode as the metal was running out and the price was very high.

However, there is a flaw in this logic as in the episode, someone said “You had to steal a mountain to make it worth your while”. This means that the price of copper is low which shatters the line of reasoning.