- Are planets, moons and asteroids our new flying platinum mines?
- All that glitters ain’t gold: there’s water there, too
- The Psyche asteroid could be a stepping stone to the outer solar system
- Space could be the only insurance we’ve got
You probably don’t give asteroids much thought unless the media reports one passing ‘near’ Earth. And a massive asteroid impact is truly a doomsday scenario. But asteroids aren’t just a threat; they may well be the key to humanity’s future. As we race to consume scarce resources here on Earth, we’re killing ourselves as surely as an asteroid impact killed the dinosaurs, just not as quickly. Finding an alternative source for the materials we need is a priority. Asteroids, it turns out, are often giant clusters of the rare metals we mine at incredible environmental cost. Sourcing these substances in space could help us slow or reverse global warming. Moreover, they contain the components of the fuel spacecraft need to reach and extract them, making the economics of developing space mining technology more than merely attractive.
But the mineral wealth space mining can produce pales in comparison to the real value of asteroids as sources of water to power deep space exploration. As visionaries like Stephen Hawking warn, while we’re slowly destroying our planet, the probability of a cosmic disaster over the long-term is high. Even if we change our habits, the Earth is a limited-time refuge for humanity. Our future as a species requires that we explore space.
Are planets, moons and asteroids our new flying platinum mines?
Planets, moons, and asteroids offer incredible mineral wealth to the companies that first develop the expertise and tech to exploit them. With little to no competition, and with rare metals like platinum and palladium abundant and accessible, experts think that the early days of space mining will resemble the gold rush of the 19th century, fueling a new era of exploration. Planetary Resources, a space mining startup with support from Google’s Larry Page and Eric Schmidt, as well as the backing of the government of Luxembourg, recently valued the mineral content of just one asteroid at $5 trillion. Designated 2011 UW158, think of this floating chunk of rock and metal as a flying platinum mine. Asteroids like this one - nearer the sun than Mars - tend to be rich in rare metals, offering enticing targets for businesses with the acumen to exploit them.
Instead of transporting these materials to Earth, Chris Lewicki, the president and CEO of Planetary Resources, believes that the future of space mining is in orbit. Given the cost of sending commercial payloads into space, he envisions space-based construction instead. Using large-scale 3D printers, nearly anything we need for exploration could be constructed there. And once in orbit, Lewicki says, “you are halfway to anywhere in the Solar System.”
But as potentially profitable as platinum and titanium are, there’s an even more valuable commodity waiting in space: water. The chief operating officer of Shackleton Energy, Jim Keravala, is another pioneer in space mining. He’s assessing its viability, but it’s the moon and the water ice trapped in its cratered surface and hidden from the sun in deep pools of permanent shadow that capture his interest.
All that glitters ain’t gold: there’s water there, too
To understand why, it’s important to realise that a single astronaut in the International Space Station requires nearly 117 kg of water per month. That may not sound like much, but every drop must be ferried from the earth to orbit, and all that weight is expensive. For future explorers, the price and logistics of moving water to space presents an insuperable barrier; the cost of sending a six-month supply of the life-sustaining liquid to Mars, for instance, approaches $50 million. Consider that the journey to the Red Planet is longer than that, and you begin to see the challenges involved. Indeed, it’s not just that finding an extraterrestrial source starts to make financial sense, it’s a necessity for human space exploration.
To send a rocket into space, engineers need to generate incredible thrust. The larger and heavier the rocket, the more energy is required. While this sounds simple enough, that energy comes from rocket fuel, which itself is heavy. Filling a rocket with water for the crew and then adding fuel to lift that liquid quickly reaches a point of diminishing return. This leads directly to a counter-intuitive figure: the vast majority - more than 90 percent - of the weight of a spacecraft is fuel. For journeys to even our closest neighbours like Mars, it isn’t possible to carry enough, because of the fuel needed to lift the fuel… a cruel paradox of planetary physics.
But we can turn physics to our advantage. A better strategy is to minimise the initial weight of the spacecraft, making it easier (and much, much cheaper) to get into space. Once in orbit, water mined from the moon could be converted into rocket fuel through electrolysis, a process in which water is split into its component hydrogen and oxygen. As experts agree, if we want to explore Mars and the rest of the solar system, it simply isn’t practical to do so from Earth’s surface - but physics is on our side in space. What we need are low Earth orbit (LEO) fueling stations, basically gas stations between the Earth and the moon, gas stations that can fuel our spacecraft where the weight won’t matter, supplying the astronauts who pilot them with the water and oxygen they need to live.
The Psyche asteroid could be a stepping stone to the outer solar system
But as we go deeper into space, these LEO stations won’t be enough. For many years, 16 Psyche, a massive asteroid that shows signs of being the iron core of a protoplanet, was the topic of conversation for space-mining experts. The only such asteroid yet found, 16 Psyche is not only a scientific curiosity, it’s also a testing ground for the potential of mining in space. In October, 2016, the NASA Infrared Telescope Facility detected the presence of water (or hydroxyl ions) on the asteroid, probably as the result of impacts with smaller, water bearing asteroids. The US based space agency has approved a mission set to launch in October, 2023, and arrive sometime in 2030. As Lindy Elkins-Tanton, NASA’s lead investigator on the project, explains, "If we go there and we discover it's easily minable and it has mineral resources that could be converted to water, then Psyche could be the perfect stepping stone to the outer solar system.” 16 Psyche, then, could be used as a second refueling stop for deep space exploration, extending our potential reach into the solar system.
Fortunately, researchers are hard at work on the tech we’ll need to exploit asteroids for their water. The Spider Water Extraction System is a result of collaboration between NASA, KSC Swampworks, Honeybee Robotics, and Embry-Riddle Aeronautical University. The SPIDER is a lightweight spacecraft capable of landing on an asteroid and taking icy soil samples. It can extract the water from them before disposing of the dry soil that remains. Projects like the SPIDER and NASA’s Psyche are leading the way into deep space.
Space could be the only insurance we’ve got
Most people don’t think of space exploration as a priority. But as Stephen Hawking, the noted physicist and master of all things mathematical, warns, “...the long-term future of the human race must be in space. It will be difficult enough to avoid disaster on planet Earth in the next hundred years, let alone the next thousand, or million. The human race shouldn't have all its eggs in one basket, or on one planet.” Developing colonies on Mars or the moon isn’t just good science, it’s smart insurance against global catastrophe.
But to reach for the stars, we need to set our sights on unsightly hunks of space rock first. In the frozen vastness between the Sun and Mars, ice-bearing asteroids promise the mineral wealth to spur private exploration and the water we need to colonise the solar system and secure the future of the human race. The first steps in this direction have already begun with investments in technology that can realise this dream.