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Lecture: Colonizing the Moon: Narrator: Listen part of a lecture in an astronomy class. Professor: There's long been talk about colonizing the Moon, both for research and as a stepping stone to Mars. But its currently impossible to sustain astronauts on the Moon on a long-term basis. Astronauts need water, food, and oxygen among other things. And right now, our only option is regularly hauling those resources from Earth. Which is ... Student: Really expensive? Professor: Prohibitively expensive I'd say. So the most logical solution is to find a way to obtain what we need from the Moon itself. From the lunar soil, the Moon's covered with a blanket of soil called the regolith. We need to figure out how to process this soil and turn it into usable resources. And we need to be able to do it right there onsite. One thing we've been investigating is how to extract oxygen from the regolith. A question Bobbie? Student: I thought there wasn't any oxygen on the Moon? How can you extract oxygen if there isn't any to extract? Professor: Well, it's true that there are only trace amounts of oxygen in the Moon's atmosphere. But in the regolith, it's a different story. Okay, you know that compounds containing oxygen are called oxide. And lunar soil is about 43% oxygen, mostly locked up in silicon dioxide, or silicon, the primary component of sand and grass. Other oxides in the regolith include aluminum oxide. Aluminum is largely responsible for the Moon's color even though it comprises just 6% of the regolith. There's also iron oxide and a few others. Student: So if the regolith has so much oxygen, can't we get it out somehow? Professor: Certainty that's easier said than done. The first step is developing the technology here on Earth. But, unfortunately there's not enough lunar soil left to work with. Some of the samples from the Apollo missions of the 1960's and early 70's, are almost gone now. We've been using them in experiments and for educational purposes for decades. And even if we still had a lot of lunar soil left, remember whatever we do have left, has been exposed to Earth's gravity and atmosphere for quite a while now. It's been many years since the samples were in a near vacuum, like they were in the Moon. And they've been jostled around and handled a lot. So, it's possible they've lost a lot of their critical properties. So in order to conduct more experiments without going back to the Moon to get more soil, that is, we need imitation lunar soil, simulated lunar soil, tons of it. So you might think, how hard could that be? We know the chemical makeup of lunar particles. Well, it's been attempted. But the product wasn't entirely satisfactory. Remember, the Moon's atmosphere is very thin, too thin to screen out radiations from solar flares, or to burn up small meteors before they hit the surface. So lunar soil's been radiated and battered by meteorites, vaporized, and weakened for countless of times over billions of years. Obviously, we can't recreate those conditions here on Earth. But even if lunar soil can be more precisely simulated on Earth, in large enough quantities, that's just the first step. Next, we need to test ways of extracting the oxygen. And there's several potential methods. One, is vacuum hydrolysis. Vacuum hydrolysis uses heat. When we heat up the materials to a high enough temperature, they separate into atoms, atoms we can capture and use. Student: So we know how to do it, how to get oxygen from lunar soil, what's the problem? Professor: Say that we can manufacture perfect, fake, lunar soil, and test vacuum hydrolysis, and the test said 'yes, we can do it'. We'd still have to transport equipment to the Moon and set it up. And also, we'd also have to harness enough solar energy or energy from other source there to operate the equipment. Okay, and let's say we can do all that. Then we're back to the lunar soil itself, which is very fine. For the most part, its consistency is dust, very abrasive and charged with static electricity. This electrical charge makes it stick to everything, lenses, mirrors, moving parts of any kind. Now these problems are not insurmountable. But it looks like it'll be a while before the dream of colonizing the Moon becomes a reality.