In a lengthy proposal released last week, former NASA researcher and current University of Central Florida professor Dr. Phil Metzger argues that the development of a mining and manufacturing supply chain in space is both plausible and beneficial. Metzger, whose work at NASA included developing Lunar and Martian architecture, writes that offworld manufacturing would benefit the economy, the environment, and science.

“The main challenge for this concept,” he writes, “is neither technology nor cost but simply convincing people it is realistic.”

Metzger describes a three-stage path to what he calls a Self-sufficient Replicating Space Industry, or SRSI, in which largely robotic mining operations would extract resources that would be transformed into useful goods in offworld robotic manufacturing facilities. The Moon and nearby asteroids contain hydrogen, carbon, silicon, metals, and other materials necessary for industry.

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Though sending all of the equipment needed for mining and manufacturing operations into space from Earth is impractical, Metzger argues that a small amount of autonomous equipment could be used to “bootstrap” materials into a more and more complex operation. He projects that only 12 tons of initial assets on the Moon could build themselves out into 150 tons of equipment (close to the amount that has been deemed necessary for a lunar colony) using local resources.

In its early stages, the SRSI would build structures from mined metal and produce propellant from water. Eventually, those structures would house manufacturing facilities to produce equipment for further exploration. As Metzger points out, the most easily and thoroughly automated industries on Earth today are also those most necessary for space development – the manufacturing of electronics, transportation equipment, and machinery. Several factories on Earth already operate with zero human supervision.

Reaching self-sufficiency through a combination of bootstrapping and equipment from Earth could take “only a few decades given adequate funding.” Metzger’s estimates suggest that, spread over three decades, the project would cost between 3-12% of NASA’s current budget annually, though the plan also depends on investment from private space operators. But, according to Metzger, the benefits of the project would be immediate.

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Metzger defends the plan to develop space against critics who have said economic activity could harm scientific inquiry. Metzger points out that there are far more asteroids near Earth than could ever be explored solely through scientific funding, and highlights the role terrestrial mining operations have played in expanding geologic knowledge.

And though he says the scientific benefits of supporting space industrialization alone justify the project, Metzger lays out a scenario where major economic and environmental benefits could return to Earth. Like many before him, Metzger argues that space industry could expand the availability of rare minerals. More adventurously, he suggests that new communications technology could allow computing to be moved off of the Earth, reducing demand for energy.

In addition to automated manufacturing, Metzger says technologies for mining and mineral processing are already nearly ready for use in space.

“Therefore,” he writes, “we can begin now.”