Editorial: “Space gold rush should not be a free-for-all“
FOLLOW the money and you will end up in space. That’s the message from a on mining beyond Earth.
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Convened last week in Sydney by the Australian Centre for Space Engineering Research, the event brought together mining companies, robotics experts, lunar scientists and government agencies that are all working to make space mining a reality.
The forum comes hot on the heels of the unveiling last year of two private asteroid-mining firms. Planetary Resources of Washington says it will launch its first prospecting telescopes in two years, while Deep Space Industries of Virginia hopes to be harvesting metals from asteroids by 2020. Another commercial venture that sprung up last year, Golden Spike of Colorado, will be offering trips to the moon, including to potential lunar miners.
Within a few decades, these firms may be meeting earthly demands for precious metals, such as platinum and gold, and the rare earth elements vital for personal electronics, such as yttrium and lanthanum. But like the gold rush pioneers who transformed the western US, the first space miners won’t just enrich themselves. They also hope to build an off-planet economy free of any bonds with Earth, in which the materials extracted and processed from the moon and asteroids are delivered for space-based projects.
“The hope is to build an off-planet economy, in which moon materials are used for space-based projects”
In this scenario, water mined from other worlds could become the most desired commodity. “In the desert, what’s worth more: a kilogram of gold or a kilogram of water?” asks Kris Zacny of in New York. “Gold is useless. Water will let you live.”
Water ice from the moon’s poles could be sent to astronauts on the International Space Station for drinking or as a radiation shield. Splitting water into oxygen and hydrogen makes spacecraft fuel, so ice-rich asteroids could become interplanetary refuelling stations.
Companies are eyeing the iron, silicon and aluminium in lunar soil and asteroids, which could be used in 3D printers to make spare parts or machinery. Others want to turn space dirt into concrete for landing pads, shelters and roads.
“Anything that can be extracted from asteroids and brought back to Earth orbit – provided it can be used – has a value similar to the launch cost of the material it’s replacing,” says Mark Sonter, one of the founders of Deep Space Industries. Back-of-the-envelope calculations show that a tonne of asteroid dust should be worth $1 million in orbit.
The first big hurdle will be building the mining robots and ensuring they work as expected before launch. “This is a standard procedure for all space missions: testing, testing and more testing,” says Zacny. The problem is that space soil, called regolith, has a few unique properties that makes testing on Earth difficult.
On the moon, continual bombardment by meteorites makes the top layers of regolith very fine-grained and abrasive, full of sharp-edged glass particles that can damage equipment. Apollo astronauts were also surprised to find that radiation from the sun has given moon dust electrostatic charge. When it gets kicked up, it clings to just about everything, and doesn’t flow readily over surfaces. The same is probably true for asteroid dust.
Without a supply of samples from space, labs are having to develop their own materials that simulate the regolith, to see how it will move through or wear down machine parts.
, at ’s Kennedy Space Center, used several different versions of fake moon dust to test a simple funnel that would deliver regolith to a reactor so that oxygen can be chemically extracted. Conducted under low-gravity conditions, the test showed that the soil won’t move through the funnel unless it is shaken significantly. “If we did this today, we would use pneumatics,” says Mueller.
, from the University of New South Wales in Sydney, Australia, is one step ahead. Rather than scooping up regolith, he has created a machine that sucks it in, and has tested it using his own brand of simulated dust. “Terrestrial technology has evolved over thousands of years. You can’t just copy and paste it onto the moon,” he says.
“Terrestrial technology evolved over thousands of years. You can’t copy and paste it onto the moon”
Since vacuum suction won’t work on the airless moon, his collection tube is instead encased in a larger tube. When they are both placed in the regolith, gas is pumped through the outer tube so that it flows into the inner one, pulling dust in with it. The fine particles suspended in the gas then move easily through the pipes, he says.
Extracting water from the moon or other space rocks presents a different challenge. Spacecraft fly-bys hint at abundant water around the moon’s poles, on asteroids and on Mars, usually trapped in layers of a dust-ice mix.
To work out the best way to dig it up, Zacny turned to Antarctica, where it is so cold that much of the ice has been created through vapour deposition, the way icy soil is thought to have formed on space rocks. “We found it to be super hard, almost as hard as concrete,” he says.
After a series of drilling tests in Antarctica and in the lab, Zacny and his colleagues developed an automated technique to extract water. First, a drill bit is driven into the ground before pulling back out with captured soil. The bit is placed in a sealed tube and heated, so that the ice in the soil vaporises, and this water vapour is captured. The drill then withdraws from the tube and spins rapidly to lose the leftover dirt. In lab tests, they found the system extracts 92 per cent of the water from samples.
“Soils on the moon have a lot of corrosive substances and toxic substances. The benefit of going through a vapour transition is that you get clean water that is not going to corrode your pipes,” Zacny says. His team has also designed a spider-like mechanism that uses the same extraction technique but for asteroids.
The work presented at the forum highlights the fact that, until recently, the real barrier to space mining hasn’t been technological, but what Sonter describes as a chicken-and-egg problem. If there’s no market in space for water and parts, it won’t be profitable to launch traditional mining operations. But if there’s no space mining, the industry that would create such a market can’t develop. That seems ready to change thanks to advances in 3D printing and robotic construction, which would allow companies to build their machines in space and save on launch costs.
Graphic: “Extraterrestrial trade routes”
“Advances in 3D printing and robotic construction would allow firms to build their machines in space”
In a , Philip Metzger, also at the Kennedy Space Center, modelled the growth of a lunar station that uses materials on the moon to build and launch new spacecraft and printers, allowing infrastructure to spread through to the asteroid belt (Journal of Aerospace Engineering, ). His calculations show that this type of self-sufficient manufacturing could eventually rival Earth-based industry.
Metzger admits that this model requires further analysis, and that there are areas in need of technological development. “It’s not any new physics, but there is a lot of engineering that has to be done,” he told the forum.
That’s not the only hurdle. Space remains a legal grey area, since the UN’s 1979 Moon Agreement is still unratified by major spacefaring nations, says commercial satellite lawyer Donna Lawler.
Mining could also be a risk to lunar heritage sites such as Tranquility Base, where the Apollo 11 lander touched down and Neil Armstrong left the first human footprints in lunar soil. In 2011, NASA recommended steps such as designating 2-kilometre buffer zones around lunar sites.
But not everyone will see rovers and tracks left on the moon as something to protect, especially if they become a barrier to human expansion in space, says Alice Gorman of consulting firm . Asked how he feels about his footprints being on the moon for thousands of years, Neil Armstrong famously said: “I kind of hope that somebody goes up there one of these days and cleans them up.”
Where curiosity leads, we follow
If the idea of space mining seems fantastical, it’s worth remembering that robots have already made some key advances. ’s Curiosity rover has drilled on Mars, a first for any machine. And Japan’s Hayabusa spacecraft recently visited and then sent back samples from an asteroid.
“Robotic prospecting is already happening,” says Gordon Roesler, a visiting researcher at the University of New South Wales in Sydney, Australia. In fact, Hayabusa is like a compressed version of the five-step mining plan outlined by asteroid-mining firm Planetary Resources, which says it will send different craft for surveying, remote sensing, sampling, mining and transportation.
“Planetary Resources’s idea is exactly the same format as Hayabusa. It’s just a matter of how we can implement it on a larger scale,” says Hajime Yano of Japan’s space agency, JAXA, who developed the mission’s sampling device.
On Mars, meanwhile, Curiosity bored into a rock and sucked in samples of pulverised material for analysis in its on-board chemistry lab. Although it only drilled down 6.4 centimetres, the technology could inform future efforts on industrial scales. “We’ve built up a good body of knowledge that can be leveraged in the future, in case that ability is needed,” NASA drill engineer Avi Okon recently told 91av.
’s next Mars rover, slated for launch in 2020, will also carry a drill and is set to return rock samples to Earth, which will allow scientists – and aspiring space miners – to do hands-on analysis of pristine pieces of the Red Planet.
This article appeared in print under the headline “Space mining: the next gold rush?”
