Space Resources: Exploring the Final Frontier, with Alex Gilbert

Notable Quotes

• Prospecting for minerals and metals outside Earth: “We have an idea that these resources are out there, but we don't know how much. We don't know necessarily where all of them are. One of the key things that we need to figure out is, How do we establish enough ground truth about the resources that are there before we can start a commercial extraction mission? We're really at a prospecting stage.” (8:15)
• Investing in space is a necessity, not a luxury: “There's often a question of, Is it worth it for us to spend money on space when we have so many problems back on Earth? That's why we need to spend money on space. Space helps issues back on Earth. What if we didn't have our weather satellite system? The potential safety risks involved, the economic damages—so many countries benefit from that [technology].” (21:48)
• Economic development in outer space cannot ignore environmental impacts: “There's this idea that space resources are virtually unlimited—that, because there's no one up there, we can't do any sort of environmental damage. I reject that categorically. A lot of those arguments ... mirror arguments that we've seen in the past about the American West, or about the oceans being unlimited and pristine areas that we can do whatever we want with. Every single time those arguments occur, usually what happens is that we then over-exploited things, and we caused damages that have all sorts of social and economic [consequences] years later. When we look to outer space, we really need to think about things from an environmental perspective from the very beginning.” (27:20)

Top of the Stack

• “Life on Venus? Astronomers See a Signal in Its Clouds” by Shannon Stirone, Kenneth Chang, and Dennis Overbye
• “Phosphine gas in the cloud decks of Venus” by Jane S. Greaves , Anita M. S. Richards , William Bains, Paul B. Rimmer, Hideo Sagawa , David L. Clements, Sara Seager, Janusz J. Petkowski, Clara Sousa-Silva, Sukrit Ranjan, Emily Drabek-Maunder, Helen J. Fraser, Annabel Cartwright, Ingo Mueller-Wodarg , Zhuchang Zhan, Per Friberg , Iain Coulson, E’lisa Lee, and Jim Hoge
• “The Space Force has a horse, for some reason” by Kathryn Krawczyk

The Full Transcript

Daniel Raimi: Hello, and welcome to Resources Radio, a weekly podcast from Resources for the Future. I'm your host, Daniel Raimi. This week, we learn about space mining with Alex Gilbert, a fellow at the Payne Institute for Public Policy at the Colorado School of Mines. Alex will help us understand the fundamentals of space mining, including key questions like: what resources are people interested in mining? What technologies will be needed to extract those resources? How will ownership of the resources be governed? And what environmental risks might we encounter—or perhaps create—in space? The answers to all of these questions are truly fascinating. So, I hope you'll stay with us.

Alright, Alex Gilbert from the Payne Institute, thank you so much for joining us today on Resources Radio.

Alex Gilbert: Thank you, Daniel.

Daniel Raimi: So, Alex, we are going to talk today about space mining. And as I was telling you before we started recording, I'm really excited because this is so far from anything that I know even the remotest amount about. I'm really excited to learn about this. But I want to ask you the first question that we ask all of our guests, which is: how did you get started thinking about and becoming interested in environmental topics in the first place?

Alex Gilbert: Yeah, thanks. I'm also really excited. I think this will be a fun conversation. So, I'm originally from Colorado, and when I was growing up, I used to do a lot of backpacking, a lot of outdoor recreation. And particularly, one of my favorite things then that is relevant for this conversation is that I did a lot of stargazing, and so I always had that outdoor aesthetic. And then when I got to undergrad, I took a geography class, and the professor started the geography class with a poem, “Something There is that Doesn't Love a Wall.” And I thought it was a really interesting way to think about geography. And then I started looking more and more into the environment as a career field and just realized that it was an interdisciplinary field. And I really liked using interdisciplinary approaches to try and identify and solve those problems. And so from there, it just kind of snowballed into energy issues, climate issues, and then now increasingly space issues.

Daniel Raimi: Yeah, fantastic. So let's start talking about those space issues. So, the first question that I wanted to start us off with was, if you can help us understand, what are the resources that people might be interested in mining in space. What are the types of things that people might be looking for? And also, this is a question born out of ignorance, but how do we on Earth even know that a given object in space, whether it's a moon or an asteroid or something else would even have resources that we would be interested in mining?

Alex Gilbert: Yeah. So, that's a great way to start really. What is there, how do we know, and why do we want to get it? So maybe to start, I'll start by rebutting an existing preconception about space mining. There are these stories that consistently come out saying that the first trillionaire on Earth is going to be a space miner, or that you look at some of these asteroids and they're worth however many quadrillion of dollars in terms of the resources available.

When we are looking at space mining, it's a very different approach to that focus on the economic riches, because a lot of that analysis is very superficial. When you really start looking at space resources today, and for the next 50 years, we're only talking about a handful of resources on certain asteroids, the moon, and potentially Mars. And for the most part, when we're talking about the resources, we're very unlikely to be bringing much of these resources back to Earth. The economics are just too challenging.

And so, when people are talking about asteroid mining in particular, they often talk about platinum or rare earth or other types of metals that have very high values. There's work going into this question right now to understand the economics of returning those to Earth. But it seems like it's going to be highly uncompetitive with traditional Earth resources. Just with the launch cost and then going back down into the atmosphere, you end up getting so many different costs along the way that even if you can get something that is very high value on a mass basis, it's unlikely to be competitive in Earth markets.

So why do we care about space resources? Really we care about space resources because it enhances our ability to do things in space. The primary one that we are focused on right now, and which will likely be the first major space resource produced, is water. Water's great for a number of reasons. You can drink it. You can split it into oxygen, hydrogen, and use that oxygen to breathe. But really the big thing that is useful about water in space is that we can use it to make propellant. We can refuel satellites and spaceships with water that we have found and then processed in space. And because the space environment has abundant solar power, it's relatively straightforward for us to take water and split it into hydrogen and oxygen, which we can then burn in a rocket engine.

And so, once we have this ability to produce propellant, it makes it much easier and cheaper to access areas that are farther away. Most activities right now are just low Earth orbit. We can do more things in geosynchronous Earth orbit. We can do more things in the system or space. We can also do more interplanetary missions. And particularly if you're looking at some sort of crude mission to Mars in the future, having refueling in space once you get out of Earth's gravity well is going to probably be an enabling technology. It's going to be really hard for you to launch all the mass that you need on one rocket.

So really, if we're trying to think about these resources, there's three big areas. There are the asteroids, which we are learning a lot more about. We're probably going to be looking in the near term at what are called near-Earth asteroids, asteroids that pass near to Earth and are within our orbital area. Those we could use for a number of resources, including water, metals, and some other materials. The moon is probably where we're going to get that first water. We have found in the last 15 to 20 years that early estimates about the moon having water have largely borne out.

And it seems like the moon has relatively—compared to what we thought—a lot of water, especially in a number of locations near the lunar poles. Both the southern and northern poles of the moon have water, and this is water ice. So it's water in the form of a rock, and often in what are called permanently shadowed regions, which are craters. And so we know that that water's there. We don't know how much of it's there, but that's probably what we're looking at first. There's some other things on the moon that we could use, but most likely anything else that we use on the moon will be to support lunar operations for either lunar research or for lunar water mining.

And then finally, for Mars, at least in the time frame I was mentioning about the next 50 years, most of what we would be using for any sort of space resource there, it could involve refueling, but it's largely going to be focused on things that we use to enable us to have a mission there. So instead of having to take all the resources that you need with you from the Earth, you'll bring technologies that allow you to extract water, extract other things, building materials, potentially chemicals, and other things that you can use for food and other types of resource production to enable to you to do more things there than you could do on your own.

Now, how do we know this? That's really where the intersection with the space resources field and space science and planetary science comes into play. In the last 10, 20 years, we've seen large strides in our understanding of the solar system and our understanding of how planets and asteroids form, and that knowledge is continuing to increase. There are a number of groundbreaking missions that have happened and are in the works that are visiting asteroids for the first time, that are bringing materials back potentially. One of the US missions right now is sending a Mars Rover that will collect samples that we will then hopefully bring back to Earth in the 2030s. And so, we're already starting to do space resource-like activities at a scientific level, and that's informing how we can do any sort of space resources activities from a commercial objective, or in support of a scientific mission later on.

One thing that is critical for the stage that the industry is at right now is prospecting. We have an idea that these resources are out there, but we don't know how much. We don't know necessarily where all of them are. And so, one of the key things that we need to figure out is: how do we establish enough ground truth about the resources that are there before we can start a commercial extraction mission? So we're really at a prospecting stage. That's really what we're moving towards right now.

Daniel Raimi: That's all so interesting and such a great way to start us off. Thank you for that foundation. So, now that we have at least a cursory knowledge of the resources and the intentions we might have with those resources, can you help us understand some of the relevant technologies that might be at play here? So for example, if we know that the moon has a certain amount of water that we want to try to process, or an asteroid has a certain amount of precious metal, how might those materials be retrieved and either used in space or brought back to Earth?

Alex Gilbert: This is one of those big questions that we're trying to figure out right now. So at the very basic level, some of the technologies are the same as what we use on Earth. I mean, you effectively could have a shovel or have a drill that you use in space. The thing though is that the space environment is very different from normal operating environments on Earth. Most of the locations are in vacuum, you are subject to substantial temperature swings depending on whether you're in direct sunlight or not. In the case of the moon, because it’s tidally locked to the Earth, the moon doesn't have a normal 24-hour daylight cycle like the Earth does. And so you have to use solar panels for most parts of the moon. You have 14 days of light and 14 days of dark, and so powering your facilities then becomes a big question.

One of the things that is challenging when we actually look at the materials themselves, we don't necessarily have dirt or geology that is the same on asteroids or the moon as is on Earth. So one big scientific challenge that we're dealing with right now is how do we create analog materials on Earth to allow us to test our technologies if you have a space shovel, is it actually going to work under the same gravity conditions that you have on the moon with the same type of regolith that you have on the moon, which isn't soil. It's a completely different process to create the regolith. We’re figuring that out right now.

Some are technologies that are on Earth. Some are radically different. One of the big ones when it comes to water—and that there's probably going to be a lot of work on it in maybe the first way we do things—is using heat to essentially bake out the water from a material. And so that's especially true when we're looking at water on the moon and some of these cold areas in the craters. If we can redirect heat towards that, either with solar energy or mirrors or some other technology, we could even put things on rovers that are sending microwaves into the ground. The water that is mixed up in that regolith can then change and it can come out as gas. And then we can use things to capture that.

There's another idea out there right now from a company called TransAstra that would capture a small asteroid, maybe five meters in diameter or so, and put it in a big bag and heat that up, and then the water would come out.

Daniel Raimi: Wow.

Alex Gilbert: Yeah. So it's some weird technologies, some new technologies. It's an open question about how economic each of those technologies is going to be. And also, how we do the technology development process because we are very early in the technology development cycle, particularly when we get to that question I mentioned earlier about the prospecting phase versus the extraction phase. And so we have ideas on how to do a lot of these things.

If you look historically, the moon and asteroids have been talked-about areas that we could use resources on and get resources from for many, many years, but now, we're actually getting to the point where we have to start designing those systems, and we're figuring out what that entails, and it's going to be difficult. We think it's likely that we'll be able to get the technologies there. We don't know how economics is going to be until we actually see what space markets look like in 10 to 20 years.

Daniel Raimi: Great. And a quick technical question, there was a term you used that I actually don't know. I think it was “regolith.” You said it a couple times. What is that term?

Alex Gilbert: Yeah, regolith. So, if you look at the material that is on the moon, Mars, asteroids, it’s not quite dirt or soil. Soil on Earth has a large biological component because there are organic materials in there. There are things that have broken down over time. When you're talking about regolith, it is a layer of loose dust, broken rocks, fragments depending on where you are. And so it's really small bits that are essentially at the top.

And so, if you've ever seen a picture from the Apollo program, and they're walking on that kind of very dusty-looking thing, that's what the regolith is. And the regolith characteristics vary a lot depending on where you are. Figuring out what resources are in that regolith and also how deep that regolith goes is an important science question when you're trying to figure out what you can do with that material.

Daniel Raimi: Great. Thank you for that. So Alex, when we're thinking about Earth, we have pretty clear—if sometimes contested—rules about which countries have the right to extract or develop resources from, let's say a patch of land or seabed, but what about the rules governing objects in space? What types of governance systems are currently in place?

Alex Gilbert: So that's a really good question, Daniel. This is one of the primary areas of uncertainty that space mining faces right now. So when you look at how space governance works, there are five major international space treaties. The two most relevant for this question are the Outer Space Treaty and then the Moon Agreement. The Moon Agreement was only signed by a handful of countries, none of which are major space faring countries. And it has provisions in it that would treat space resources for commercial purposes, similar to how we do things for the deep seabeds. So if you've ever heard of deep sea mining, there is an entity, the International Seabed Authority that oversees the permitting and determines how countries are able to exploit and use the deep seabed. The Moon Agreement would envision a similar type of organization for space resources, but it's not in effect.

The only commonly accepted treaty that governs space resource extraction is the Outer Space Treaty. Now the Outer Space Treaty does not say anything explicitly about space, but it does have a very important provision. It's called the non-appropriation provision. And that is due to the history of the outer space for years. So, this treaty was originally negotiated in the 60s. It was signed in 1967. It established the constitution of International Space Law. So it's a 50-year-old treaty. At the time it was signed, it was only the Soviet Union and the United States as major space countries. And the point of the treaty actually was primarily to be a non-proliferation and a security treaty. It wanted to try and prevent a nuclear weapons race occurring in space.

And so, it has a number of provisions that are focused on that, but the non-appropriation clause was an aspect of that. It didn't want to create a space land rush. So, it didn't want the US to fly to the moon and plant a flag and say that “we own the moon.” And so, under the non-appropriation clause, a country or a nation cannot claim any celestial body in outer space. When it comes to space resources, it's a difficult question to figure out what that means legally. So clearly, the US cannot go to the moon and go to a place it wants to mine and say that we own this land and we are going to mine it. But there is emerging legal interpretation, which is based on state practice from how the US extracted lunar rocks during the Apollo mission and the Soviet Union as well, that says that even though you don't necessarily own part of the celestial body, once you take resources that are in place, you then are granted ownership of those resources.

And this has been an emerging debate and discussion for a while. There are now several countries that have legal frameworks around that question specifically. The US is one of them. In 2015, we passed a space law. And under that law, it guaranteed the ownership rights of a US citizen that extracts abiotic resources in outer space. Abiotic means that if you find life, you don't own it, but if you go and you find water or you find metal and you extract it from the moon, once you've extracted it, you now—under US law—own that material. The degree to which that is an okay claim under international law is hotly debated right now. There is a bunch of international work that's happening. And this is something that the US government both under the Obama administration, but increasingly under the Trump administration, is considering to be a major policy question. They're trying to get this resolved in a way that facilitates future space commerce.

Daniel Raimi: Wow. That is so interesting. And so, if I wanted to put a bag around an asteroid and heat it up and extract something, I could own the thing that I extracted, but I wouldn't own the asteroid itself. Is that about right?

Alex Gilbert: Yes. And that is one of the interesting cases, because in theory, if you extract every single thing from that asteroid and then use it, that asteroid will no longer exist, but you own all the resources. So it's a question of where do you draw the line? That's a very specific case, but it creates a new type of legal system compared to how we do a lot of things on Earth. And it's still highly uncertain about how much this will be recognized. I think generally the way that most interpretations are going right now is that if you have scientific resources, so if you extract something like the Apollo moon rocks, or you send a mission to an asteroid to extract scientific samples, I think that's clearly accepted, particularly if it's done by governments. The big question is: what about commercial property rights? How does a commercial company get involved with this?

Daniel Raimi: Yeah. Well, so a related question that came to mind: before our interview, I was reading parts of the Outer Space Treaty, and there's a provision in there that says, and I quote, "the use of outer space shall be carried out for the benefit and in the interests of all countries." And so, when I read that, the question came to mind, the reality is that there will be geopolitical and commercial interests that are at play. So how realistic is that aspiration when we think about future space mining and distributing those benefits equitably across society?

Alex Gilbert: So, this is a really critical question, and it's actually one of the reasons that I'm starting to do work in this area. If we're looking at outer space mining as a future part of the economic sphere, as part of the geostrategic sphere, how do we manage that in a way that's equitable? How do we manage that in a way that's fair? And also, how do we make sure that that does not lead to future conflict back on Earth? That's going to be a challenge, but if you look at the text of the treaty and you look at the principles, it differs somewhat from the Moon Agreement and the UN Convention Law of the Sea, which address a different model for how benefits are supposed to be given.

Under that model, the benefits are financial. So when you get a permit to drill and extract resources from the deep seabed, you actually put aside some amount of your profit that is then distributed to other countries. And so there's financial profit sharing. Under the Outer Space Treaty, you don't have a clear mechanism for that, and you don't necessarily need to have that. Benefits does not mean that you need to have a company that's profiting commercially, needs to share those profits in order for there to be benefits. To the degree that an improved space economy benefits all of humanity, you can meet the requirements of the Outer Space Treaty, both in principle, and just also what we want to do. Particularly if we can do what we want to do with space resources, we can greatly expand space science. We can make it much easier to do space activities.

If you look at GPS, for example, GPS has done wonders for the global economy, people all around the world benefit from that for various simple things, from getting directions on your phone, to having products delivered to you on time, to having services saved, to being able to fly in the airplane and know that you're going to be able to get to where you're going. And that is US-funded, but everyone benefits from that service.

And so, when we look at space mining, if we do it in the right way, we can make sure that it benefits science for all of humanity. We make sure that the economic benefits—at least indirectly—benefit people. And also one of the things that we can do politically is we can make sure to involve other countries. If other countries want to be involved with US space activities, we should welcome that. We should really welcome a group of nations working together in outer space for our joint interest and figure out ways to do technology sharing and other activities to make sure that this is something that benefits everyone. We don't want to have conflict in space. Let's figure out how to do that.

Daniel Raimi: That makes me think of that phrase, “a rising tide lifts all boats.” Is there a space equivalent for that? Because that's kind of what this sounds like.

Alex Gilbert: I would argue so. I think if you look at a lot of things that are happening with space activities, there are major benefits from having outer space technologies. There's often a question of: is it worth it for us to spend money on space when we have so many problems back on Earth? That's why we need to spend money on space. Space helps issues back on Earth. What if we didn't have our weather satellite system? The potential safety risks involved, the economic damages—so many countries benefit from that. Right now, there's a big controversy about the mega-satellite constellations that Elon Musk and others are proposing that would provide internet service around the world. If those actually go through and they're successful, we could change how much of humanity is connected to the internet in a way that is as revolutionary as getting cell phones to the developing world.

So, it's possible. I think that if you look at things academically, there has not been as much work on that just because it's still in very early phase, but we want to try and figure out how to make sure at this early stage in the industry to make those ethics and those values a key part of how we do things.

Daniel Raimi: Yeah. And I'll just point listeners also to the RFF initiative called VALUABLES, which is a project that's all about trying to understand the economic benefits of observing Earth from outer space and how having satellites and technologies like those you're describing benefit all of us. So, one last policy question, which is, you mentioned US policy around space a couple of minutes ago. Can you expand on that a little bit more and tell us about how US policy is looking to incentivize exploration and developing governance structures in space?

Alex Gilbert: Yeah, certainly. So, the US is quickly emerging as one of the major—if not the only—leader in actual space resources development. There's a number of other countries that are looking at this right now. Luxembourg and the United Arab Emirates in particular are looking at developing space law frameworks that would facilitate space resources development, but the US uniquely has a set of characteristics that give it a big head start.

First of all, it's got a really good innovative business culture. We have a very strong aerospace industry and that in particular is being led by a number of very innovative rocket companies that are reducing launch costs considerably. We also have a very strong university and public-private partnership system on the side of NASA to help us develop a lot of these technologies. And so we have a lot of opportunity here, and I think policy and governance is following accordingly.

So, there was the 2015 law that I mentioned, which was really kind of groundbreaking in that it guaranteed the right to own resources. It didn't actually authorize people to go up and go get stuff in space yet. So we're working on that right now, but there've been a number of actions from the Trump administration to support space resources in the last several years. They are looking at space as a big area of strategic competition but also of economic value. And so they're promoting the private and commercial space industry.

NASA has been really effective at using public-private partnerships to extend its capabilities and its capacities. And I was actually really excited about when we had this podcast date set, because I just found out last week, NASA released a new solicitation. And under that solicitation, NASA is asking companies about whether they will provide a service, and that service is scooping some regolith from the moon and selling it to NASA. So if that's done and that solicitation has a goal of 2024, that would technically be the first commercial space money. That could happen within four years.

And that's part of the overall Artemis program that NASA is pursuing. NASA wants to use private companies because it makes things a lot cheaper for them. And it also reduced the technology development risk. If they have two or three companies competing for a service that they themselves would have to provide, they would have to use a lot of their limited science dollars to try and develop that capability in house. Instead, they can put the risks on the private companies. Private companies can drive the cost down. And when it comes to space resources, if NASA is doing anything on the moon like it wants to with the Artemis program, they're probably going to look at commercial companies to provide that for them.

And so, NASA as a government-anchored client is probably going to be the chief source of space resource purchases in the next 10 years. And meanwhile, the US is starting to look internationally as well. So, the Trump administration is currently developing a set of bilateral treaties called the Artemis Accords. The accords themselves are not overtly revolutionary. They largely enshrine existing principles from the Outer Space Treaty and other relevant international law, but they provide a path forward to have a country start engaging with us on a lunar program. And if we can be successful at that, if we can get our traditional space partners to buy into our space resource ideas, then it's possible that we can address a lot of that regulatory uncertainty and really start moving forward towards extracting these resources and using them to benefit people.

Daniel Raimi: Yeah, that's great. That's so interesting. It's going to be really fascinating to watch that develop over the coming years. And so we only have a couple minutes left, but because this area is so new to me and I imagine it's new to many of our listeners as well. I'm sure there are a million good questions that I simply haven't thought of to ask you. So I want to just use our last couple of minutes to open it up and ask you to talk about any other topic that we haven't touched on yet that you think is important for us to know about.

Alex Gilbert: Yeah. So thanks for that question. I was excited when you mentioned you'd be asking this. So right now, I'm working on my PhD and I'm looking at a number of different areas, but one area that I'm really interested in is environmental protection. So when we talk about space, there's this idea that space resources are virtually unlimited—that because there's no one up there, we can't do any sort of environmental damage. I personally just reject that categorically. I think if you look at a lot of those arguments, they mirror arguments that we've seen in the past about the US West, about the oceans being unlimited and pristine areas that we can do whatever we want with. Every single time those arguments occur, usually what happens is that we then overexploited things and we caused damages that have all sorts of social and economic and other negative aspects years later.

When we look to outer space, we really need to think about things from an environmental perspective from the very beginning. The number one safety threat in low Earth orbit right now is not the fact that you're in space so much as the fact that there's space debris that other humans put up there. There's a bunch of things that's up there that it could hit the International Space Station. It could hit satellites. We have satellites consistently damaged. We've had satellites have collisions before. And so that's a space environmental problem that is clearly being accepted right now, but most policy conversations about space sustainability are limited space debris.

If we're talking about seriously going to the moon and mining the moon, we need to be thinking about environmental protection and sustainability from the beginning. The lunar environment is hostile in certain ways, and it does not have people. And we think it probably does not have life on it. That does not mean that the lunar environment's not fragile, and particularly the regolith in many locations on the moon. If you land on that regolith in the wrong way with a rocket, you will shoot that regolith into the atmosphere of the moon. And because the gravity is so low, you could actually end up in the situation where enough of these landings could start creating a regolith of dust cloud around the moon, which would then impact all sorts of future lunar activities.

Now, that's an extreme example. There's one way we can get around that and not do that. And that's creating lunar landing pads. There's a lot of enduring focus on that right now, but until we ingrain our environmental values into our outer space activities, we have the risk of unforeseen impacts happening. And that could limit what we do in the future. And particularly if you're a company, even though there might be some concern about environmental regulations stymieing you, it also helps protect that company.

One area that I've been looking at and particularly lately is the National Environmental Policy Act (NEPA). There's an open legal question about whether NEPA applies to outer space. A coauthor and I have some work that we've been doing in this area that we think indicates it probably should, but that has not been tested by the courts yet. And if NEPA does apply to outer space, that could provide the initial framework to start environmental law in outer space. Now the Clean Air Act, or the rest of the environmental tools that we have in our toolbox, might not be as applicable in outer space, but NEPA could work because NEPA is a precautionary regulation that requires you to look at your impacts before they happen.

And that's exactly what we need at this stage for environment protection in outer space. We need to know what things could happen before we make decisions, even if we decide that we're willing to risk it. One related aspect of that—that we have seen some legislative progress on—is protecting lunar heritage sites. So there are places all over the moon and actually all over the solar system that we've sent past missions to that we think as a country, we might want to value. And so particularly the Apollo sites, we don't want to necessarily have tourists visiting those sites. The environment and the area could be very fragile. And so there is a possibility that we could have legislation that would protect those sites from any sort of future interference.

Daniel Raimi: Wow. So many interesting issues to think about just on that one topic on environmental protection in space. And so this has really piqued my interest so much in all these topics and I'm sure it has for our listeners as well. So thank you again, Alex, for coming on and sharing your knowledge about space mining. It's going to be a really interesting area to watch in the future. So let me close us out with the question that we ask all of our guests, which is asking you to recommend something that you've read or watched or heard related to the environment or otherwise that you think is interesting and our listeners might enjoy.

And I'll start with a very brief recommendation for an article that just has my favorite headline that I've read in probably a few years. And the headline is “The Space Force Has a Horse, for Some Reason.” So, the Space Force, the newly established wing of the US military, has a mustang named Ghost. Ghost is part of an equine patrol unit that patrols Vandenberg Air Force Base in South Carolina. Their program's actually been around since 1996, but this I presume is the first time that the Space Force has gotten a horse. So just a fun little article and I enjoyed reading it and getting a little chuckle. But how about you, Alex? What's on the top of your literal or metaphorical reading stack?

Alex Gilbert: So, there's an article that just came out today that's really interesting. And it reports on observations of phosphene in the atmosphere of Venus. And this is really exciting from a planetary science perspective because it is a potential biomarker, meaning that phosphene might be coming from biological material from life on Venus. Now there's a number of reasons that that might not actually be the case, but the researchers themselves weren't expecting to find this, and this is actually a technique that we're planning on using to look at exoplanets, planets beyond our solar system to see if they have life.

And so, this could be a really interesting moment. There's going to be a lot of talk about this week, but in terms of our conversation, I think it's really interesting because the reason that I really care about space resources and think it's interesting and important, is it will allow us to do so much more space science. If we actually think there could be life on Venus, it would be much easier to do a mission to Venus if we have a robust and vibrant space sector. And so I'm going to be digging into that article later on. And I imagine there's going to be a lot of media on that topic this week.

Daniel Raimi: Very cool. Well, so just to people know, we're recording this on September 14th, but we will have a link to at least one article about this on the show notes. So people can go check it out. Well, we'll end it there. And once again, Alex Gilbert from the Colorado School of Mines and the Payne Institute for Public Policy. Thank you so much for joining us today on Resources Radio.

Alex Gilbert: Thanks for having me. This was really fun.

Daniel Raimi: You've been listening to Resources Radio. If you have a minute, we'd really appreciate you leaving us a rating or a comment on your podcast platform of choice. Also, feel free to send us your suggestions for future episodes. Resources Radio is a podcast from Resources for the Future. RFF is an independent, nonprofit research institution in Washington, DC. Our mission is to improve environmental, energy, and natural resource decisions through impartial economic research and policy engagement. Learn more about us at rff.org.

The views expressed on this podcast are solely those of the participants. They do not necessarily represent the views of Resources for the Future, which does not take institutional positions on public policies. Resources Radio is produced by Elizabeth Wason with music by me, Daniel Raimi. Join us next week for another episode.