Valued at over $8.4 trillion and growing at a 4.1% compound annual growth rate, energy is the largest industry on Earth.
Humans are prolific energy consumers, and soon there will be more humans in space.
Jeff Bezos, Founder and CEO of Amazon, anticipates “millions of people living and working in space” in the coming decades. Bezos is so confident of this outcome that he is investing more than $1 billion per year into his space transportation firm, Blue Origin. An in-space population of this magnitude will require enormous amounts of energy to live, work, and transit. This energy will come from solar power, which is more effective when gathered in space due to the lack of a filtering atmosphere; and chemical rockets, which will be the primary transportation mechanism for the foreseeable future.

The most efficient chemical rocket propellants are composed of cryogenic liquid oxygen combined with liquid hydrogen or methane. Initially, the propellant needed to fuel the space economy will be launched from Earth, as both the United Launch Alliance (a joint-venture of Lockheed Martin and Boeing) and SpaceX have proposed to do in the near future. However, there is a much more attractive way to source the propellants needed to support a sustained human presence in space: mining it.