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Reid: If we as a species ever want to get off this planet, we’re gonna need to find stuff we can use to build things and survive in space. Lucky for us, there’s a lot of it. I’m talking about water, iron, platinum, gold: you name it. It’s just locked up in asteroids. And a growing number of people believe that if we want to live in space, we have to mine them.

Most of the asteroids in our solar system are in the asteroid belt, which is between Mars and Jupiter. But there are over 14,000 NEOs, or Near Earth Objects, which are asteroids floating around a lot closer to home.

Right now, we’re most interested in carbonaceous chondrite asteroids, or C-type asteroids. They’re mostly made of life-friendly stuff like carbon, phosphorous, and nitrogen. Any future space settlement will need a lot of these elements, because that’s what makes up breathable air, and fertilizer for growing crops.

But the best thing about C-type asteroids is that they’re basically chunks of clay. So you’ve got all those organic elements stuck together with water. And in space, water is more valuable than gold. We need to drink it, obviously. But we can also separate it into hydrogen and oxygen to make rocket fuel – y’know, for those interplanetary gas stations. And due to its density, water can even protect us from radiation, which is one of the biggest dangers of spending a long time in space.

Launching a single gallon of water from Earth into orbit costs about 83,000 U. S. dollars. Not to mention, the astronauts have to bring up all the water they’ll need for their entire stay in space. So if we could just mine our water from asteroids, that would be way better. There are also S-type asteroids, which are made of rocky minerals and some metals, and M-type, which have a bunch of metals.

Since they’re both denser than the C-type asteroids, they’d be more difficult to mine. But, more important than precious metals, they hold materials we need to build machinery or tools in space. Iron, nickel, cobalt, and silicon can make semiconductors and glass, and platinum-group metals can make ultra-conductive parts that won’t corrode. Try to imagine anything cooler than putting a 3D printer in space, filling up its cartridges with materials mined from asteroids, and printing out pieces of a space station.

So what’s stopping us? Why’s Babylon 5 not already a thing? Well, the first thing we need to do is survey the asteroids. To do that, we need telescopes -- lots of telescopes, like, hundreds of them -- that we can send out to look at our NEOs and tell us what we could find inside of them. And simple optical telescopes aren’t good enough. We need spectrometers, which are special instruments that can tell us what elements are present in a sample by looking at how they reflect light and heat. Ideally, those telescopes would be able to latch onto an asteroid’s surface and do a chemical analysis on the spot.

We do have the technology to do that now: Curiosity, the Mars rover, has an onboard lab called the ChemCam, for analyzing the composition of Martian soil. But the ChemCam was expensive to build and get to Mars, and it’s one of a kind. Mass producing hundreds of spectrographic chemistry-lab-slash-telescopes and then sending them up into space... it’s not something we know how to do in a cost-efficient way.

There are people working on those instruments, though. Two American companies, Planetary Resources and Deep Space Industries, are looking to crack into the asteroid mining business. The country of Luxembourg wants in on the asteroid boom too – it’s offered a 200 million euro line of credit to any asteroid-mining company that wants to set up headquarters inside its borders. And NASA is launching a mission in September 2016 to send a spectrometer-equipped, sample-collecting space lab to a nearby C-type asteroid.

This is the OSIRIS-REx mission, and one of its goals is to tell us how accurate spectrometers are. The OSIRIS-REx spacecraft will measure a bunch of stuff, including the materials on the surface of the asteroid, then collect a sample to send back to Earth. If the spectrometers say there are compounds in the asteroid clay that aren’t actually there... then we’ll need to figure out how to improve our technology. But if the instruments turn out to be right, we’re in business.

Once we know how to find asteroids, and figure out what’s inside them, we can start thinking about ways to mine those materials and use them for our space technologies. If asteroid mining pans out – especially if we have more water in space for drinking, refueling, and radiation protection – the frontier of the solar system will really start to open up. And space stations, lunar colonies, and Mars settlements start to sound like something that could happen in our lifetimes.

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