What Elon Musk Won’t Tell You About Settling Mars

Zach Weinersmith


Paris Marx is joined by Zach Weinersmith to discuss why building space colonies will be much more difficult than the space billionaires want us to believe.


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Paris Marx: Zach, welcome to Tech Won’t Save Us.

Zach Weinersmith: I’m excited to be here.

PM: I’m really excited to chat with you. You and Kelly have this new book called a “A City on Mars” that really digs into the nitty gritty of what it would actually take if we wanted to set up life in the solar system, on the Moon, on Mars, on space stations, what would really go into that. I feel like even though it’s approached in a really light way, it gets to these details in a really concrete way that we often don’t hear discussed when we get into these discussions. So I want to dig into all this with you. But before we start, I do have to ask there’s a lot of mention of Canada in this book. I’m obviously Canadian, and there’s a random mention of Corner Brook, Newfoundland. Now, I’m from Newfoundland, where’s all the cannabis stuff coming from? Is there a specific reason?

ZW: I hadn’t thought about it. I’m suddenly wondering if I have an implicit bias or something that I need to reckon with? I’m just thinking off-hand as a joke about how under international law, you could technically pack a Moon base full of soldiers and I believe we use Canada as the country perpetrating that because Canada is generally perceived as well-governed and probably wouldn’t do that [Paris laughs]. Maybe that was the reason, I didn’t put too much thought into it. Corner Brook comes up. Have you heard of Corner Brook? You’re familiar with this place?

PM: I’ve been there.

ZW: Really?!

PM: Yes!

ZW: Say it comes up in the specific context of company towns, because it’s the well-studied company town. There’s a book that dedicates a significant portion to it as an example of how company towns are actually more cluster-fucky, than you might imagine from the stereotype. So, Corner Brook being an example of a company town that was set up and actually went bankrupt repeatedly for decades before making a profit. Maybe I shouldn’t get into the weeds. But actually, Canada comes up a lot in the study of company towns, because you have a sparse country with lots of resources. Someone was telling me once that everyone makes fun of Canadians for Tim Hortons, but he was like: Look, Canadians are really brand loyal because this giant continent was shaped by company towns, setting up cities around the country. I don’t know if that’s true. But when you’re researching company towns in North America, Americans tend to think Appalachia, but actually, of course, there’s a rich tradition in Canada, which seems to be qualitatively quite different.

PM: That’s fascinating. I felt like Corner Brook in particular, when it came up, it just came up in a way where it was like: Company towns and Corner Brook, obviously, you should all know about the history of Corner Brook, right? And I was like: What? Me maybe, but the general reader?

ZW: No! Well, if you want to talk about company towns, I could go into this whole thing.

PM: I just found it funny. Especially being a Canadian, and particularly someone from Newfoundland, reading your book, and just having all these references come up.

ZW: That must have felt really weird. Like, 80% into the space of a book, let’s talk about Newfoundland [both laugh].

PM: So anyway, getting back to the book more generally. Why did you and Kelly set out to write this book in particular, and how did it evolve from the idea that you initially had to what you ended up writing?

ZW: We had written a book called “Soonish,” which is a more typical book, it’s like: Here’s some cool technology stuff and we’ll kind of explain it to you. What we came across is that there, and this is true, there’s been a genuine revolution in the pricing of getting mass to space, and that is largely down to SpaceX. There are now a couple other competitors, well, SpaceX via a government program to accelerate. It’s a whole story. But basically, the sine qua non of this is this company called SpaceX, that for a variety of reasons, drastically dropped the costs. So big picture, if you go back to Sputnik in 1957, it’s extremely expensive to be put in space, let’s say it’s something like one to $10 million per kilogram. That drops, depending on your estimate, 90 to 99%, by 1970, at the end of the Apollo program. The view at that time, especially if you read books from the early 70s is like: This just just gonna keep going, there’s gonna be a vast expansion, but we have the data and it’s a little hard to compare, because you get apples to oranges stuff.

But loosely speaking, the price actually went up from the early 70s, plateaued at a high level that the shuttle, in particular, the Space Shuttle was extraordinarily expensive. That was the way things were. You’ll read books from the 90s, it’s very cynical. It’s like: Oh, my God, we had all these dream. Blame is cast everywhere, but a pretty good place to point the finger is just that space is really hard. There was not a lot of downward cost pressure. I won’t get into the weeds, but basically, SpaceX comes along. They successfully dropped the price by, depending on your estimate, three-quarters to four-fifths. That’s where we are now, which is a big reason, you’re seeing this huge uptick in all sorts of space stuff and th fantasies that existed in the early 70s are coming back.

We were sort of excited! Because this is really cool tech and it really did change things. So, the number of satellites we have up now is getting close to the number of satellites that were ever launched, prior to the modern era. It’s really changed. So, we’re like: Oh, space settlement, and it is coming back. But we talked about it, they weren’t focusing that much on the human factors, economics, psychology, and biology. We were like: Let’s write that book, but how we’re going to do all this stuff. So, the big change that we went through — and this is like two years into our research, it was way deep — we’d accumulated so many things where we were like: Well, this seems much harder than advertised in lot of the books by advocates or random articles you might read, but in reputable publications

It also seems like a lot of obviously undesirable stuff is being treated as sort of marginal. To give a concrete example, the general existential risk of having a vast million ton objects orbiting close to what’s called Earth’s gravity. Well, meaning if they fall, bad stuff happens. And then the absolute dearth of talk about the existence of international law, that is broadly agreed upon by many nations when it comes to creating states in space. And so by that time, we were just kind of like: Oh, my God, there’s this whole big picture that is, I would say, broadly negative about near-term settlement that is not being reckoned with. That’s a little less true now, I should say, there’s a couple of books that came out around when ours came about. So there are a couple other books on this. So I think there’s starting to be a movement, which is maybe in response to the drop in cost and the greater access, but that’s where we fit in.

PM: I feel like the book arrives at this perfect time, as you say, because there is all this interest in space. There is all this discussion about: Are we going to go to the Moon; are we going to go to Mars? What is this future endeavor that we are going to take off? It has really infected the narrative coming from NASA as well and some of the programs that they are putting out there. But as you say, there is a lot of discussion about the possibility and what we might be able to achieve and why we should do this, but not so much is in the public discourse about the reasons that we should maybe a bit more, not even skeptical, but even just realistic about what we can achieve here. I feel like the book does a really good job of saying: Here’s all the things that you should know that you don’t hear very often. But also, we’re going to present it to you in this way where it’s not just this really bland, dry text, but it’s really fun to engage with and learn about. So it’s perfect for average people who want to know more about all this stuff.

ZW: Yes, for me, a good pop-sci book is a lot of depth that’s presented well on something you’ve never heard of, or never thought about. And that’s what we were going for.

PM: It’s fantastic. Why is it that so many of the things that we hear about space settlement come so much from the enthusiasts, often libertarian ones? And how does that shaped the way that we think about building a base on the Moon or a city on Mars? How does it distort the public conversation about those things?

ZW: It often comes from libertarians, it’s not without exception, there have even been a few people who proposed — we have a whole paper out that’s not in the book about space communes. Because there is a much smaller leftist thread of: We’ll leave capitalism behind, which I think is wrong for opposite reasons. But the reason the discourse is probably bad is essentially that most of it is by advocates. I’m all for advocacy, but the problem is, on a lot of issues, you have advocates on both sides, but usually in the context — like I said, that’s changing — but usually in the context of space, one of the things we did was read basically as many books as we could find from the past trying to predict the future of space settlement. I don’t know that there are hardly any, I can think of a small number of very recent books that take a broadly negative view. But mostly, they’re very pro. It’s not too surprising.

Actually, even when I was showing this manuscript to other pop-sci authors, and I was like: Yeah, we’re going come in with a negative view of whether this is a good idea. They’re like: You can’t do that. You can’t write a book for nerds about how you don’t get the thing. Writing a book sucks. You’ve written books. It’s wonderful to have done and to imagine doing, but there’s a part in the middle where it’s just absolute misery. So, you probably wouldn’t power through that, generally, if you didn’t really believe in the thing or think there’s something really interesting. So I think that’s a lot of what’s going on. Just as an example, the kind of seminal book on Mars missions is by Robert Zubrin called “The Case for Mars.” I would broadly construe him as something as not exactly libertarian, but right-leaning and very pro-America, frontier type of stuff, libertarian-conservative, maybe you’d say. It’s a 400 page book on this topic of space. So basically, it completely leaves out international law that would bar a lot of the stuff he’s saying we should do, but also leaves out stuff like radiation, which is a big open question, like what it does.

He actually has a section on what’s called hormesis, which is not definitely wrong, but it’s the idea that exposure to some of something might actually be good for you. Let’s say it’s insufficient. But that’s what I mean. So a really good example, we were talking a little beforehand, the Moon where people talk about setting up a gas station, this is a Jeff Bezos thing. The idea is: Well, the Moon has some water, and that’s true. Water can be cracked into hydrogen and oxygen. Those are typical rocket propellants, so we can have a Moon gas station. The problem is there’s not that much water — end of story [laughs]. There’s just not that much! We compared it to, we found a small manmade lake we found, I think it was in Mississippi or Alabama, just just one that happened to about the right area. It’s is quite small, but it’s also very hard to get. But setting that aside, if you could get it all, it’s just not that much. It doesn’t ever renew, well, not on the scale of human lifespans. This stuff is really salient and it gets left out, I could guess as to why, but I think when you’re motivated on one side, you tend to emphasize some things and demphasize others.

PM: It also doesn’t sound good for these billionaires who are trying to build these space companies to say: Actually, all these visions that we’re giving you to justify what we’re doing, are going to be way harder to achieve than you’ve been led to believe.

ZW: Companies have to have vision statements. But if your vision statement is: We’ll have a permanent waystation on the Moon, it’s just not true, you cannot do it with the water supplies that are available.

PM: Before we dig into the deeper issues there, the final question I have about this is: We have all these big visions that are out there now, that have really gained steam, that people have been hearing, I would say more and more often over the past decade. Especially as you say, as SpaceX has become bigger, and as Blue Origin has been competing with it, and as that has kicked off further investment in the private space industry, in particular. Why is NASA increasingly embracing these visions? As you see, it’s Artemis missions and going to the Moon and talking about that being a stepping stone to Mars and stuff. Why has the public space agency embraced these visions that, as you say, have a lot of fundamental issues with them?

ZW: Well, it’s always dangerous to try to get the motivation. Sometimes with some billionaires, they tell you and then you can go off that. Let me lay some things on the table and not say for sure I know why. Because it’s a good question. But let’s say so for one thing, these agencies are essentially political. The right view of NASA, is that it was created as a political act and it is essentially to gain… All space agencies especially for human spacefaring, it’s 100% about prestige. It’s a political behavior. I always feel bad saying that Apollo was a political action, more than it was a scientific action. But these agencies need to get funded; they need to have an identity. So I think on the robotics, that’s highly justifiable as good science, people are interested in that. To put a dude on the Moon — or now it’s going to be one man, one woman on the Moon — there’s not really a good justification for that.

But the public, we know this from history, is super interested, and really respond strongly to it, so that’s probably part of it. One thing that really irks me — and this comes out of Department of Defense people around the world, comes out of agency heads, comes out of politicians — is this almost salivating for Cold War part two, with China or whoever. So, you’ll hear people say things like: Well, we have to have a Western government on the Moon, because of the Chinese get there first x, y, z. And I’m over here, like: There’s nothing worth doing on the Moon, plenty of awesome science, but there’s nothing worth doing in the sense of an investor gives you money, and you come back with more money and give it back to them. There’s nothing in this traditional economic sense worth doin on the Moon. It’s not going to make us richer, it’s not going to end poverty or any of these other outlandish claims. It’s purely down to politics. So, again, without wanting to second guess people’s motivations, I do think there are obvious funding reasons, and PR prestige reasons, why people are motivated to do this stuff.

PM: That makes a ton of sense and it’s a really good way to understand it. Maybe we’ll come back to that history, because that was a really interesting part of the book as well. But let’s get to some of these bigger visions and what is wrong with them. So, if we hear Elon Musk talk about it, the idea is always: We’re going to go to Mars, we’re going to set up a city there. We’re probably going to do it by the end of the decade, if we really believe his more outlandish claims. His timeline keeps moving, but I know that’s one of the timelines that he’s put out there, st least to start this settlement project. I imagine part of that is about going to the Moon on the way to Mars, though, he talks way more about Mars than then going to the Moon. I know that the Moon is more part of the NASA mission that he is talking about going there and SpaceX is involved with and things like that as well. So if we’re just thinking more broadly, if we were going to set up a settlement on the Moon or on Mars, thinking about the environmental conditions first. What is the real roadblock there?

ZW: The first thing to say before I even launch in, is everywhere else is worse! [Paris laughs]. That is what I’m about to describe, sounds everywhere else is substantially worse in space that you might go: Okay! Just a super quick rundown, if you go to the Moon you’ve got 1/6 Earth’s gravity — we actually don’t have a lot of data on this — and we think probably rapidly, fairly rapidly, degrades bones, muscles, and then other more subtle stuff.

PM: Not a big deal.

ZW: Not a big deal. Well, I mean, to be honest it’s possible, it isn’t a big deal. It is a big deal on the International Space Station where you’re in zero gravity. It’s possible 1/6 gravity, which you have in the Moon, is enough to at least stretch out the damage. But just for reference on the ISS, you lose something like 1% of hip bone density per month. It’s a zany, Harry Potter spell rate of bone loss. But could be fine on the Moon, could be not. But we’ve been to the Moon, it’s true. We’ve been there for weeks. So Aldrin and Armstrong walked on the Moon for about three hours, we calculate about 1% of their time was trying to get the flag to stand up. So, we just don’t have a lot of medical data on that kind of thing. You’re also exposed to radiation, even when you’re in the International Space Station, you’re under the magnetosphere, sorry, the Van Allen belts. Down here we have more protection, because we have the atmosphere, but at least up there you have some. On the Moon, you have none.

The Moon is only very weakly magnetic and no atmosphere. By the way, no atmosphere is also bad because you die really fast. It’s basically the same as if you’ve ever been diving, which I have not, but if you surface too soon, nitrogen comes out of your blood, and you get enormous pain and maybe die. Space is of course much worse, because the pressure difference between inside and outside is like infinity. So for reasons I could go into, that’s actually really non-trivial because it means there’s a lot of management of breathing gases and stuff. The dust on the lunar surface, you see pictures and it looks like a black and white photo of Arizona, it’s actually much worse than that. So the Moon is this rock, that’s a product of stuff slamming in it for eons. There’s no wind; there’s no water; there’s no life — no nothing.

The results of that is if you put it under a microscope, it looks like knives. It’s little jagged bits of stone and glass. Seems to be bad for equipment. By the way, it’s also statically charged because you’re just exposed to radiation. So astronauts described it as clinging to your suit, which is a problem in all sorts of ways. Just to give one example, you might not think of, those suits or white to reflect sunlight. If you fall into this dust — which inevitably they did, because they’re carrying around these giant suits in this unfamiliar gravity regime — you get covered with this plastic color, so you absorb more heat, while also being a little bit insulated by the dust. So it’s like: Oh! This is a major problem. We think maybe if you breathe too much of it, it would cause silicosis which is when you lose the ability to breathe easily because your lungs are so scarified over time. It’s also known as stone grinders disease.

Lunar days are 14 earth days long extreme heat, lunar nights are 14 earth days long, extreme cold and your solar panels are not going to work. But that’s enough about the Moon. Really quick, Mars is broadly similar, it has more gravity, it’s 40% of gravity, roughly. Has an atmosphere quite thin, you still die immediately if you go outside, but it has a thin carbon dioxide atmosphere. Which is nice, because your plants can consume it. It’s not true on the Moon, which is very poor in carbon, which is a really non-trivial problem for any farming operations. Carbon has to be made in stars — you can’t just make it from scratch. But the downside of that atmosphere is that you get worldwide dust storms. So even though you might be tempted to just have solar panels, because Mars has earth-like days, the sun gets blotted out worldwide for weeks at a time.

By the way, that soil that gets kicked up has a high concentration of perchlorate — this is a hormone disrupting chemical. If we talked about reproduction, think about trying to have kids in an environment where there are hormone disruptor storms. Then last thing I would say is also there’s distance. So the Moon is relatively close, you can almost have a live conversation, about two and a half seconds the signal gets there and back. So it’s like a little bit of lag but not bad, which is good for a variety of reasons, psychological, equipment, help in an emergency. Mars, the closest rendezvous, you’re about three minutes each way. There is no live call to mom, 22 minutes at the longest distance. Equally important, if you’re on Mars, the launch window to Earth only opens up every two years, for orbital mechanic reasons.

You can only go home every two years unless we have super futuristic technology. It’s six months there, six months back, again, unless we have super futuristic technology. So it’s a much bigger long-term venture, much more dangerous. Then the last thing then is Mars is also exposed to radiation. Another problem with solar panels on Mars is there’s an inverse square law for how much light you get. So, if you double the distance, you get a quarter of the light. Mars gets about 40% the light of Earth, I believe. It’s a little better because of the thin atmosphere. If you are doing solar panels with a battery system, they’re going to have to be tremendous, double any solar setup you would have on earth at least. Perhaps, I’m all in on solar, it’s great. It’s the future, but it has a huge land footprint, which means a huge maintenance operation on this hostile world. That’s your best place.

PM: Sounds very appealing. My main takeaway was that I could record a podcast with somebody on the Moon, but not on Mars.

ZW: That’s right, it would still be a little bit annoying.

PM: But doable, but doable. I knew, going into reading the book, that there were a lot of challenges that went into going to the Moon and going to Mars. Obviously, I knew that you couldn’t breathe on these planets, without manufactured oxygen and tanks and special settlements and stuff like that. But the thing that really got me, that I didn’t know as much, was the stuff about the soil, or the dirt or whatever, on Mars, just being jagged glass and stone that’s also electrically charged. The soil on Mars being toxic, basically. I was like: Oh, these are things that I hadn’t heard before, that you don’t hear Elon Musk telling you all about when he’s talking about our great future in space.

ZW: What drives me crazy, and we’ve gotten this critique. For a lot of engineers, my brother’s an engineer. Some of my best friends are engineers! But there is this kind of mindset that says: If there is a solution to the problem, then it’s no longer a problem. But we actually had people were mad at us for even mentioning perchlorate, which struck me as bizarre because they were like: Well, you just have to cleanse them. It’s fine. You can use water, and it’s true. If you put them in a moist environment, you can cook off the perchlorates, but they also do seep into plants.

Our joke was like: We live on a little farm and we are about to buy it. They’re like: Oh, by the way, this soil is 1% hormone disruptors, but it’s okay if you just run a little water through it, and you’re good. It’s a bizarre standard. I don’t know if we want to get into it, but all that stuff I described, people say there is a solution. That’s true. I’m not saying it’s impossible! Humans could one day do this. It’s just that when people double book their astronauts or triple or quadruple. They’ll be like: Well, I have to run the farm and the fission reactor, and they have to clean the solar panels and have to do all this stuff that no human could possibly do. Then of course, when you add in, I don’t know if we’ll get to the lack of an economic return, it gets pretty dicey.

PM: I think before we get to the economic piece of it, you also mentioned the human side of this. You mentioned reproduction and the issues that might cause there. But just in general, our body has evolved to live on this planet, and in this gravity and in these kind of biological conditions. What would it mean for us then to go to somewhere like the Moon or like Mars, and then try to live there? Do we know what that would mean for human biology? Do we have a good grasp of that?

ZW: Broadly speaking, I would say no, we don’t. I should note, too, you’re absolutely right. I think it’s a great way to think about it to say evolution designed us for this one place. And the rest of the universe we know of is not like this one place. I would add though, about something like 60-70% of the surface of this planet, you die pretty quickly, if you’re just transported to it. So you’re were adapted for parts of this planet. So the data we have come from about 50 years we’ve had space stations. That’s obviously the best data on human physiology in space because the other trips are really short. So I’ve already talked about the loss of bone density, loss of muscle mas, seem to lose vision. So the main thing I want to say though, is take all that stuff and imagine trying to have children under those conditions.

So this is where we really don’t have data. We absolutely don’t know enough about whether you can even survive for a long time on the Moon or Mars because you can imagine if you are losing, let’s say it’s a lower rate, like maybe 0.2% bone density per month, you’re still in real trouble eventually. But try to imagine having children, we have nothing on this. Your listeners might think that NASA is a systematic program for humans spacefaring. It is not, space station’s our political activity, embodied in metal and plastic. You would think if: I want to know about humans, can we have babies in space? That I could look up the textbook or the sequence of experiments we’ve done. The experiments done on space stations don’t work that way, they’re ‘grab bag-y.’ People ask for time, and sometimes they get it.

So if you look at all the reproductive date, it’s like: Well, one time we sent quail eggs; one time we said geckos; one time we sent lizards; couple times we sent rats. We find a variety of results. There have been cases where there was stillbirth. There’s some ominous hormone results, like low testosterone in males, low oxytocin in females, which is especially worrying if they’re trying to give birth. Is it the microgravity? Is it the radiation? Is it just the enormous stress of being a rat that can suddenly float and doesn’t know why? What you really would want, if you wanted to know if humans could reproduce in this environment, is a longitudinal study where you would start with something like gerbils or whatever, and have them do generations.

So, the other big question here, often when this comes up, it’s like: Can you have a baby in space? But if you want a settlement — and the sine qua non settlement is permanent, is families that have kids who have kids who have kids — then you would want to do that with a rodent first, and then you would want, to do it ethically, or at least borderline ethically, I think you can even debate the animal part of this, you would want to scale up taxonomy towards primates and then, ultimately, to humans. We don’t have anything like this. By the way, often the experiments we do have show scary stuff, like cell deformation, stillbirth, as I said, the hormone stuf. You have this prima facie if you expose people to all this radiation, all these weird conditions, like on the Moon or Mars, because of all the stuff they described, they’re probably living underground in tight quarters.

All this stuff put together suggests it would not be shocking if you had a higher than normal rate of kids born who have difficulties. And where this gets really scary is on earth, when you have kids with special needs. Some of us might complain about the quality of services they get, but there are services, there are places for those kids. And frankly, you’re just in an environment where people have regular lives, where they’re not trying to survive every day, so they can take care of these kids as well as possible. On the Moon or Mars, it’s going to be very difficult. And you find, we found three different quotes of space advocate saying some version of well: We’ll have to let natural selection do its thing, which is, obviously, ethically horrific, I think to anybody. I would say notably, ethically horrific in any posture.

It doesn’t require you to have a stance toward economics or politics or anything to think mass experimentations on babies is a no, no. But I would say those quotes we found are the people saying it out loud. If you have 1000 people on Mars, trying to make a go of it, without this science saying that it’s okay under some conditions, then it is just obviously, ethically a catastrophe. So, the idea that we’re going to have a million people on Mars in 2030 years, as Elon Musk says, is either just bogus, which I think it probably is, or an ethical calamity in waiting. Notably, none of the people making these claims are spending the kind of vast money you would need to get a handbook on orbital obstetrics, probably because there is no return on investment. So yikes.

PM: Yikes is right, especially when you start talking about space eugenics and stuff like that. It gets really dicey, really quick. And like you say about Musk, I often feel a lot of these grand visions are more like PR for his company than something he really thinks he’s going to achieve. But I’m sure there’s a mix.

ZW: It’s weird, right? Because we have this question of is Elon Musk, is he just a grifter? Is he just saying stuff to take money? But if you read his biography, I think that the smart money is that he’s at least to a great extent, a true believer. Which is like whether that’s good or bad, if the true belief is: If we just go to the Mars frontier, everything will work out fine. That’s much scarier than just grifting. Probably, it’s like you say, there’s a spectrum from a pure grift to a pure belief, and he’s somewhere in between showmanship level, but it’s hard to know what’s in people’s true beliefs, of course, even when it’s your own beliefs.

PM: Taking the belief and really deceiving on the timeline.

ZW: Absolutely, yes.

PM: Before we get into the economic piece of it, there’s another proposal out there, as well. You mentioned Jeff Bezos and how he wants to use the Moon as this gas station for, not so much the settlement of Mars, but more the creation of these large floating habitats in space where we’ll live and will move industrial production and we’ll do do all our farming and earth will become this big natural park that we go visit every now and then. So it can be our little eden, and can just exist and we’re not destroying it and whatnot. What is the issue with the idea of building all these big space colonies? Is this the solution to the problem of colonizing Mars or the Moon?

ZW: So Bezos is in a very long tradition. So, people have been proposing giant orbital space station since the late 1920s, but the big fleshing out comes in the early 70s, the main guy is Gerard K. O’Neill. I think there’s a documentary about him now. But it’s an interesting story, he is a Princeton particle physicist. It’s the late 60s, and it’s hard to attract physics students anymore, because people want to be more politically engaged at this time for obvious reasons. So, he comes up with this idea where we’ll have a course on: Could you put a big space station and put people there? And the set of problems this solves, especially for an idealistic college students in the 60s, is: Well, is simultaneously a fix for the environment, because we’ll offload stuff from the biosphere while generating solar energy. And you’ll get a chance to try out new governments, like the back to the land movement that was going on then and they will try out communes will try this and that.

So there are detailed proposals, the main book on it is “The High Frontier.” And the short version is, and I could go off in a whole detailed thing on this, but basically a big problem is you have to have mass. So typically, you want to situate these in a Lagrange point, without going to detail that’s basically the point where stuff sits in space relative to some other things, so relative to Earth. Which is nice, it just sits there. It can face the sun all the time, so you get the solar power. The problem you need to build the damn thing. So usual proposal — this was O’Neill’s proposal, although you’d have to fix the carbon problem — is you launch mass from the Moon. So if you want to visualize this, imagine a mass driver, which is a sort of maglev train that goes up and then the track just ends.

You would load up sealed containers of moon rock, and you would fling it and there’d be a giant space catcher’s mitt, which by some means, or another — descending from the massive amount of energy you supposedly could have — you convert it into suburbs. So people have seen these pictures of dinner partiers years of the 70s and there’s a toroidal Tuscan village. O’Neill knew that was ‘BS’ at the time, even if you could do this, it would be so expensive, you’d be living in submarine barracks. But set that aside. That’s the grand vision. We even say, like acknowledged in early 70s makes a bit of sense, because renewables are not really there yet, other than hydro. O’Neill himself says, in the early 80s, he thinks solar is never going to work. There are really big concerns. There’s Paul Ehrlich stuff, “Limits to Growth” stuff. There’s a view that resources are going to run out soon and there’ll be unavoidable mass famines, like hundreds of millions of deaths in the Third World, sometime in the 80s.

I don’t want to poopoo environmentalism, or any of this stuff, but the particular claims being made at that time were much more catastrophic that turned out to be true. So these people see it as a third way, like we don’t have to degrowth. We could still have this lifestyle, we just had to move people off planet. So one is that they’re hard to build because of that mass problem. Another thing though, you can calculate how many people do you have to boost to tread water? Right now it’s about 200,000 people a day would have to go, just to keep population stable. 200,000 a decimal a day, 80 million people a year. More than Germany in a year has to go up right now. There are under 20 people in space. That’s pretty high on a historical scale.

So, the idea is that this is one, going to happen anytime soon, but two, going to solve climate change, because right now rocket launches quite pollutive, is just crazy. Jeff Bezos says we’ll move heavy industry. We checked one heavy industry, I think it was concrete — I always mix up concrete and cement. But anyway, produces a lot of CO2 doing this and the amount of tonnage per year on Earth is in the billions, which weighs much more than the standard 200,000 people we already can’t boost. It’s just not serious. Even if you could do it, if you want to talk about lowering the risk of environmental calamity, spend some money on putting some solar panels in New Mexico. Don’t do this the zany stuff, it’s almost certainly not going to pay off. If you started doing it immediately it would make the environment worse. So, no.

PM: Damn! I was really hoping this one would work.

ZW: [laughs] Yeah, they are awesome. They’re the coolest visuals in the history of space!

PM: They look really nice. It’s interesting because in the book, you point out if we were really concerned about what is going to happen for the future of humanity and where we should be living, even an earth that is climate ravaged, where a bunch of nuclear bombs have been dropped, it’s way harder to live than the conditions that we have right now, is still so much more livable, and a good place to be than anywhere else in the solar system, or the universe that we know of.

ZW: Yes, it’s not even close. Go to the bottom of the ocean; go to the worst part of Antarctica, you can still get water, you can still breathe. At least in the ocean, there’s still life you can eat. It’s just not even close.

PM: If we talk about the economic angle of it, because this is really core, especially when you start to talk about Bezos and moving heavy industry into space. But so much of the discourse that has arisen around this growth of the private space industry is that: Yes, you have the blue origins and the SpaceX was doing the rocket launches and they’re bringing the satellites up and stuff like that. But this is the first step to building a space economy where we’re going to be mining all these asteroids that have trillions of dollars in value associated with them. And that is going to make us unbelievably prosperous. Is this economic argument one that actually makes any sense?

ZW: We don’t think so. So I would say the money’s — If you want to make money doing space stuff everywhere out to geosynchronous orbit, that’s about 24,000 miles high, is good money. So you can do remote sensing, navigation — we all access our phones all day long for stuff that talks to space. You can do data acquisition, data transmission, military stuff is obviously quite valuable to have space technology. Beyond geosynchronous though, there’s nothing that exciting. You don’t need to get further out. You don’t get a better view on Earth. Actually, the trend now is for lower Earth orbit stuff, like a couple hundred miles high. So the more zany stuff, which is usually Moon mining, Moon mining just seems to be objectively crazy.

Someone in your audience is being like: What about the valuable helium-3? We talked about it very briefly. We originally had a whole long thing and our editor was just like: No, you can’t have 2% of your book be about helium isotopes that are not irrelevant. We have a whole rant about why it’s a bad idea, but if you want details, there’s a paper we put in the footnote which goes into detail basically. Actually, there’s a Canadian reactor that can make helium-3 as a byproduct, a fission reactor. It’s called a CANDU reactor, which is really good acronym game. I think it’s like Canadian Deuterium, something. I don’t remember. Anyway, other than that, there’s really nothing worth getting.

There’s a quote, I can’t remember used this, from Michel van Pelt, who’s a guy at ESA (European Space Agency). He said, “If there were bars of gold on the surface of the Moon, it would not be worth it to go get them.” You can sort of visualize why. Imagine Apollo program, you walk up the rocket, it’s the size of a skyscraper, most of it’s propellant. You dispose of the rocket when you go up. By the time it gets, at last, to the Moon, it’s a little tiny, dinghy a little tiny bell. I think a grand total of half a ton was taken back from the Moon. So, you try to imagine the extraordinary costs of this program, hundreds of billions of modern dollars. The idea that you’re going to make money getting stuff from the Moon. I mean, course you can drop the costs, you probably would, but it’s still not even close. Especially versus just digging a big hole on Earth.

The other big claim is asteroid mining. People somehow have this idea that there are platinum asteroids floating around, or gold asteroids — there aren’t. There are asteroids that are relatively high in some relatively high value metals, but the ones that are worth getting, at least anytime soon, which come kind of closest to Earth. We found one estimate that said they were on the order of 10. So you imagine creating all this specialized equipment to go get this stuff, it’s pretty questionable. Throw in that risk of what are the rules on if you want to kick a million tons of iron or nickel toward the home planet? Seems like there should be a little concern about that. Beyond that, there’s not a lot of economic cases, I don’t think I’ve seen. But the basic deal is, it probably always is going to be a better idea to do it on Earth, the case is probably just not there.

PM: You always got these bad answers for us — nothing is possible [both laugh].

ZW: Well, let me just say. So we have been accused of saying it’s impossible. I would never want to be saying it’s impossible, because there’s a whole history field saying things are possible. But it’s much more boring than that. It’s about the marginal dollar. So it’s like: if you have 10 bucks to spend and your goal is to lower existential risk, anytime soon, it’s obviously not go to space. If your goal is return investment, look at the bones of all the companies that were asteroid mining startups. It’s not like someone had a zany energy startup and got there, but then the price dropped and the thing they were selling. They haven’t even got off the paper stage before they went bankrupt. I’m a kind of optimistic person. I’m like a bit of a tech nerd. I’m excited about many other things. But this one is just kind of like in the silly zone.

PM: The question about asteroid mining is really fascinating and whether the economic piece of it makes sense. And what you say about the low earth orbit, and the things closer to earth actually being something that these companies can make money doing makes sense, when you see exactly what SpaceX is doing. Where it’s firing up all these satellites, where it’s controlling so many satellites with its Starlink system. That is where the money is, and that is where it is making its money, it’s not going to try to colonize a planet and where it is going further than that it’s doing it with NASA money in order to do it. But there’s another really big piece of this book, which is really important, and which you really don’t hear Elon Musk talk about or any of these advocates really. So, that is the question of space law and international law and how this all applies to what is going on in space. You talk about some of the different treaties that exist out there and that do govern space or could potentially govern space into the future.

You can go back to the earlier days, to the Cold War, and they had the Outer Space Treaty, which started to set a framework in order to make sure that these great powers weren’t going to be warring over space. But also to give some degree of confidence, I guess, to other countries around the world that these parties weren’t just going to control it. There were efforts after that to do a follow up, which didn’t work out, which would have made space more of a commons. So, that is being challenged today by new regulations that are not happening on the international stage, but are coming from the United States, and from other countries allied with it, that seek to promote this idea of a private space economy and the private ownership of resources or control of resources in space. This is a really broad way of saying, how should we understand the way that space law is actually going to impact what is going on here and what barriers does it throw up to these grand visions that billionaires and space advocates promote to us?

ZW: How it will play out, I don’t know. I can tell you, what we try to do is say, first of all, there is international law. It’s important because it’s often left out. International law does bind to the behavior of nations. It’s not infinite, and obviously, there are power dynamics. But on the other hand, when you have a treaty, if you think it’s all about power than the treaty is a statement of what the powerful nations think the rules should be. So it does matter. Also, international law kin tells you what would be a provocation or not. One example I could give you, we obviously have this whole war between Russia and Ukraine. Russia could start dropping nuclear weapons. Obviously, they are constrained in some way there is some limit.

I think part of that is down to international law, which it would just be considered such a massive violation of norms and treaties. The response would be complete isolation, even from nominal allies. So there is international law, it matters. As you say, the big document for space is the Outer Space Treaty when it comes to space settlement in particular. Most relevant is Article Two, which says no sovereignty and space. Basically, no space countries. The US can’t, as Newt Gingrich proposed, claimed the Moon should be a US state. Likewise, you can’t start a new state on the Moon. People will argue about this, but very few legal scholars will say you can.

PM: I always thought Canada was the 51st state, but now I’m learning it’s actually going to be the Moon.

ZW: It’s one of my favorite tidbits is Newt Gingrich just being like: We need it, it’ll be like the Old West, only it’s the Moon. We just need to get enough people. So, the Outer Space Treaty answer is basically no. Which is important because a lot of people who are advocates for going to space want to start nations. Robert Zubrin says this, Elon Musk hasn’t said it particularly but it’s looming in a lot of proposals. And part of that is this idea that Earth sucks and somewhere other, like it’s insufficiently libertarian, as you said, is a common one. But also there’s a more, maybe a centrist version of that, which is: Well, most people feel the Earth has some problems, a lot people think it’s too bureaucratic, or we’re getting like a monoculture. If we could escape from that and start new stuff on Mars, that’d be awesome.

The basic deal is legally you can’t and when I say legally, it is important. So when people hear illegal, they think domestic law, but in international law, which is law by the usual scholars definition, there’s not an enforcement agency. There’s no police who like show up and put you in country jail. There’s cultural responses by the countries who agreed to these things. But if say, tomorrow, you found out Russia had secretly put a base on one of the lunar poles and said: This is ours, that would under international law be like drastic provocation. Even if you agree with me that there’s no good reason to do this. That it would be a broadly stupid move in terms of resources. It would still be a massive provocation. I don’t know what would happen, but it would be a big deal.

So that’s the sense in which I mean, it constrained behavior. And the question is this going to stick around? Because a lot of people think it’ll go away. Smetimes it’s because they want it to go away. Sometimes I think it’s a cynical view of the international order that it’s all bs anyway. One thing we’re really big about is that you have to understand Space Law, which does make space probably a sort of commons, depending on definition, is not some sort of one-off. So in the 20th century, there were three times humanity had to decide what how to deal with a whole lot of territory that opened up due to technology. That’s in Antarctica, that’s in the bottom of the sea, and that’s the rest of the solar system. But worth noting Antarctica, the seabed, that’s 60% of the surface of this planet. You’d be you sound crazy, if you were like: I’m goingn claim this. Well, Antarctica did have claims.

In all three cases, by different means, but broadly speaking, all three were regulated as commons. That is what humanity decided to do in the second half of the 20th century. We’re not going to fight about these things, because we don’t want to repeat of the battle days where we fought over territory, but also because it’s probably nothing worth getting in these places. So we really don’t want to fight over it. Let’s just do science and leave it alone. So in Antarctica, there’s a chunk of Antarctica, non-trivial one that’s claimed by three countries, Chile, Argentina and the UK, and it’s just cool. They don’t relinquish their claims. They don’t make new claims. They just promised not to be jerks about it. That is held since 1961, I think. This is how we regulate things where it gets weird is you can’t have sovereignty, but you can probably claim infinite resource,. Which leads to all sorts of perverse outcomes. So like, you can’t claim the Moon as sovereign territory, you could write Elon Musk in big letters on it with a laser beam. There’s no explicit prohibition against. Though, there’d be some environmental contamination questions, but no prohibition,

PM: Pease don’t give him any ideas!

ZW: He might do worse things than that. Maybe that’s a good trade. So that the long-standing US view, which is starting to become the international norm, is that you can access resources ad libitum, as much as you want. That includes that scarce water resource. So as you said, we tried — we meaning the international community — tried to regulate all this in a way that would have been broadly like the seabed is regulated now. Which there’s an international agency which bureaucratizes and slows down the process of territorial claims. That became the main agreement, which is technically enforced, because enough nations signed it, but none of the space powers, none of the big powers signed it. So it’s kind of a dud. Into the breach comes the Artemis Accords, put up by the US, in line with a bill passed under Obama and an EA, an executive order, signed by Trump basically saying Americans could do what we want. 20 nations have signed on this, not like little strong arm nations. It’s like Germany, the UK is real, and Australia. Serious countries have signed this.

PM: I think Canada is on there, again.

ZW: Canada, right! Alright, so there will be Moon Canadians. Basically, it’s scary, because you can start under this agreement to make quasi-turf like claims. You can designate what are called safety zones. They’re explicitly not sovereignty claims, but they’re kind of like: This is ours, don’t land here, you’re going to mess up our stuff, we can’t guarantee your safety, you’re in our safety zone. These have unspecified radius. The way we say it is, whereas in the 60s, you had to fight to do a stunt on anywhere on the Moon. You could get into a turf battle, the best spots on the Moon are actually quite limited. They’re on the orders of hundreds of acres, probably. So to me, that’s scary. It’s all pointless. The science would be awesome. But you worry you get into these quasi-turf like claims that escalate international tensions down here.

PM: On that point, if, as we’ve been talking about, this idea of settling the Moon, let’s not even talk about Mars for now, seems so distant and remote and difficult to do and having very little economic case. Why is there such a push, when you see the US government and these other 20 countries passing these laws or signing these accords. That are aimed at making it so private companies can access resources on this far off body that is not even on our own planet? Whereas, as you say, what happens in Antarctica can stand and has stood for 60 years, and there’s no attempt to disrupt, that I know of, what is going on down there and the regulatory framework and international law framework that’s been set up there. Why is there so much focus on space when it seems like something that is far less accessible? Whereas something that’s so much closer, and is regulated as a Commons can just stand and there’s no attempt to overthrow that.

ZW: People who disagree with me would probably point out, it’s not a bad point on its own, which is: Well, space, we could just go do stuff. There’s a lot of regulations down here and maybe there should be. So, you can’t make the Moon worse. It’s already horribly inhospitable, so let’s just go to resources there. But as I said, it’s not worth it. Like, it’s just not even close. You probably have to do some environmental damage. Then there’s a question about, do we want to actually tear up huge chunks of the Moon? Which is this destructable record of what’s happened to Earth over time. Why there’s a push for it is really hard to say. I would point out two things. So one, there really has been a drop in the cost, it will probably be the case that before long, it’s cheaper to do stuff on the Moon. So I think that gives people the idea that it’d be worth doing, I just think a cold calculation of the numbers doesn’t bear it out.

One thing I would point to, though, it is really hard to overstate the salience of space activity as a prestige activity for companies and people. There’s a wonderful book by Alex MacDonald, I think he’s still the chief economist at NASA called “The Long Space Age,” I highly recommend it. His theory is: Even if you go back to observatories, doing stuff in space is mostly costly signaling, either by individuals or countries. It’s basically a way to display prestige. One of my favorite stories from the history. Famously, both Khrushchev and Eisenhower don’t realize satellites are going to be a big deal. They think they’ll be a big deal for data, but they don’t think the public is going care, it’s a science project among many.Then Sputnik goes up. The story from I think Khrushchev’s memoir, is that he sort of says: Good job, everybody. Goodnight. Then wakes up and the whole world is on fire. Just every headline of every newspaper everywhere is Sputnik.

And Eisenhower is also caught off-guard. He thought all the space stuff was kind of crazy. Especially the moonray stuff he thought was completely bonkers, and there’s a good argument he was right. But the world went wild and you can see there’s polling from this time, where there’s a big shift towards thinking the Soviet system is better. It’s not overwhelming but it’s something like a double digit swing in a lot of Europe. Now, I should say there’s a big point to be made here, which is, this is, of course, during the period of high decolonization from like 1945 to 1975. So trying to get alignment is a bigger deal than it is now, although it’s still a big deal. So, if people are talking a lot about the importance of this step, and it is to an extent.

The way I like to say it: Let’s just say tomorrow, you found out China, not only had a base at the bottom of the Arctic Circle, but was saying: This is China, we’re claiming a two mile radius at the bottom of the sea. You’d probably be like: Well, that’s weird. But I don’t really care. Whereas for whatever historical reasons, it’s in the public consciousness space. If China did the exact same thing on the poles of the Moon, I think there’d be a massive response, because it would broadly be considered that China was way ahead of us on everything. That’s what happened with the Soviet Union. The basic deal is they weren’t, but this stuff is so deep in people’s heads — and maybe that’s just biological, the Moon just seems different. Whereas, if you found out China had a city on the bottom of the ocean, you’d be like: Cool. If you found out they had a city on the Moon, you’d be like: Wow, China is going to win the next century, period. So I don’t know where it comes, from my perspective, I really don’t know. There’s just a kind of salience that is unique to space.

PM: Kind of the result of stories that we’ve been collectively telling ourselves for a very long time, basically.

ZW: I think that’s a good guess. I honestly wish there was a detailed treatment of why we feel this way. And I don’t know what the answer is.

PM: No, that’s interesting, though. There have been a ton of interesting facts that you’ve given us through this conversation, and we could go on and on and talk about even more. But after looking at all this, what is your assessment of what space settlement would actually look like, is this a realistic thing? And if it was something that we wanted to do? What would be the best way to do it? Is what Elon Musk wants to do, to try to get us there as soon as possible, and just start throwing people onto Mars and hopefully building up a city? Or would our approach look much different if we really wanted to do this in a responsible way?

ZW: So a couple of things there. So the first bit was: Is this feasible? I think you could sort of turn Earth into a Garrison planet where all resources are devoted to getting people on board. You can imagine a sci-fi story where there’s some giant object that’s going to hit Earth and we’re toast and you’re like: We have to do this, period. I think it’s literally doable, you’d have to obviously deal with the reproduction stuff. We didn’t even get into, like handling any ecology, which is a whole other question. But I would actually say that, to me, that’s one of the few situations where you could justify moving a lot of humans quickly without a lot of this data, if the alternative was worse. That seems unlikely. The objects that are there are quite rare. But I think it is literally feasible. I don’t want to say it’s not it’s just it would require an extraordinary amount of money and be ethically dicey outside of sort of particular circumstances.

I do want to add too there is a non-trivial thread of argument that we just shouldn’t do it. That it actually just increases existential risk without benefit. And Daniel Deudney is the guy for that, not very popular in the space settlement community. He’s an international relations guy who’s also a space geek. He wrote a book called “Dark Skies,” which analyzes a lot of this in extraordinary depth. It’s kind of like a scholarly book. It’s not a sit on the beach and read book, but if you want the ‘just say no’ version of this, he’s the guy. If we wanted to do it, what we argue for is something we call “wait and go big.” So, the wait part is scientific, basically. We need the reproductive science, we need ecological science, which is a whole other thing.I think that rockets and that kind of technology, is stuff that will probably take care of itself because it’s economically remunerative, at least a lot of it is. But the like: Can we have babies? Can we run a sustainable ecosystem in space? That you need to just shell out for and it’s going to take a long time to get the data. That’s the wait part.

Go big, is something we thought about at the end of a lot of these steps. A lot of stuff we didn’t get into benefits from scale. So probably ecosystems benefit from scale, because you have more redundancy and less risk of calamity. Human psychology, which we didn’t get into, probably benefits from scale because you just have more resources for people more opportunities for getting help. Likewise, if you are in a situation where a lot of people have special needs, or other stuff, or need special treatment, again, scale means division of labor. One thing we didn’t really get into is we talked about company towns economics. If you want to have better working conditions a classic important thing is labour mobility, that is to say: Do workers have a choice? That’s a really hard thing to get in space, which is like the most isolated you can be and also where you have to have enough oxygen to move to somebody else’s place. So again, scale probably improves labor mobility, which would be a good way to make conditions better for workers.

PM: I remember Elon Musk talking about space indentured servants, so.

ZW: Yes, I don’t think he said indentured servants!

PM: Yeah, not the term.

ZW: It’ll be great. They’ll just owe the company, their existence and million dollars in debt. That will happen. So again, to say having just a lot of scale. In other words, instead of trying to bootstrap if you can quickly get to like a million people. If you had all this other stuff solved, you’re probably better off for a variety of reasons. The one last caveat I’ll offer and then I’ll give my slightly optimistic conclusion. We talk a little about war in space mostly to dispel some myths, because I really don’t know what war will be like in the distant future. We don’t like to speculate too much. But it is worth noting that there’s categories of weapons that we don’t often use on Earth. Part of why we have these interdictions is because of risk to everyone else.

Part of why these Nuclear test ban treaties came along is there was a big experiment in the 50s that showed up — strontium-90 in baby teeth. Strontium-90 is a nasty radioactive isotope also shows up cesium-137 is a water soluble, nasty isotope. When you blow up nuclear weapons, either for war or not, you put the stuff in the atmosphere, you harm all of us. You kill some of us due to premature cancer death. Likewise, with biological or chemical weapons, there’s similar problems with blowback or escape. So we don’t like to use these, they do occasionally get used, but generally they’re prohibited. There is a debate about why but one reason is thought to be the risk to everyone. Well, if you throw one of these from Mars to Earth, or vice versa, you’re safe, and they might shoot it back at you. But at least you’ve taken this issue off the table.

So, usually, when we talk about going to Mars, wherever is as a reduction of human existential risk, because one plus one equals two, you have two options. But we say the math is more complicated and I think it’s trivial that it is a bit more complicated. But actually, even in the long term with a lot of development, we might have higher existential risk. So with that said, if we really had to do this, if I was running the agency for getting this done, and had the budget, where I would spend would be three places. One would be that reproductive science, we went through that, eventually, you’d want to get maybe on the Moon to see how partial gravity works and this and that.

Two would be closed loop ecologies, which you didn’t get into. But basically, the idea is you need a sealed bubble, where you can have an ecosystem that doesn’t destroy itself, and provides enough food and oxygen and clean water. That’s a big problem. Biggest one ever was three acres, had eight people in it. We need to scale to a million people. If it’s linear that would require a greenhouse the size of two Singapores. That would be part two, ideally, those two things merge on the Moon somewhere. You have a sustaining ecosystem on the Moon, where people can have children, then maybe you can do Mars. That would obviously take many decades. Last thing, I want to shout this to everyone who’s 18. There’s this whole thing called international law, it sounds boring, but it’s like only area in human life where you can scribble ideas on a piece of paper, and they just changed the hinge of history.

Part of why sea law is what it is, is because people were writing in the 17th century about what they thought it should be. So it’s an area where you could really make a difference by doing scholarship and showing up at conferences and talking to people about what the ideal space law should be. We think it should be a slow bureaucratic space law, other people want a kind of dynamic, more capitalist version. This is a fight we’re going to have during the next 100 years, and it will shape much of the future. So, all of these three things: space babies, closed loop ecology, international space law research, which are just objectively awesome. Separate from what the best ideas are, they’re just really cool stuff to study. That’s what we should be looking at, if we want to settle space and not cause harm to ourselves.

PM: I love that. That gives us a really good insight into what we should actually be thinking about if we do want to one day realize this. When I was reading the book, my real takeaway was, this is theoretically something that’s possible, there’s a lot of roadblocks to achieving it. But if it is something that we want to set ourselves up for in the future, there are steps that we can start to take. There is science that we can start to do to make sure that we are heading in that direction aearning if this is something that is really feasible. That these issues of reproduction and things like that are not going to be hard lines that we just cannot overcome, and that that research needs to be done in order for us to get there.

But I feel like the important thing was simply that this is not something that’s going to happen in the next decade or two, as a lot of these tech billionaires and advocates seem to want us to believe it’s not going to be something that is going to save us from climate change or protect us from the existential risk of something going wrong on this planet. Ultimately, the bigger question, the bigger priority is to make sure that Earth is a good planet to make sure that we are stewarding it well. First of all, because it’s going to take way more time if we ever hope to settle the Moon or Mars in any real capacity beyond maybe a science outpost at some point. But further than that, because we should want to have our house in order here before we try to go anywhere else and set up a human colony, civilization, whatever we want to call it there.

ZW: I think that’s it. I appreciate that it took a while to say it because like we really tried to be nuanced. It’s complicated. Space is a real actual place that lives outside fantasies. The way I’ve come to think of it — I don’t know if Kelly would agree with me on this, but let me just state my view — which is essentially that space settlement done right, is an activity for a very advanced and very harmonious future civilization. It’s for Star Trek, it is not an economic proposition, most likely, it’s an aesthetic proposition. That’s sufficient as long as we’ve taken care of the existential aspects. But to get to be that Star Trek civilization, you have to survive the next 100, 200, 300 centuries while still developing. So, that’s where the husbanding our resources on Earth property comes in. Because people tend to say: Well, why are we spending on space when we could be spending down here. And I think often that’s a false trade off because if we reduce funding for NASA, it’s not obvious to be that we’d all get piled into solar panels or something. It’s a more complicated story

PM: Maybe just tax cuts?

ZW: Quite plausibly. And so to me, it’s really all about, we need to make sure we don’t destroy ourselves down here. That means reducing existential risk. And space is not going to do that and might do the opposite of we don’t do it the right way.

PM: I think that’s a really important way to understand it. And it also says: Don’t stop being excited about space; don’t stop being interested in space, but be realistic about the settlement piece of it. Let’s do our science. Let’s learn about it because that’s the real interesting thing. But let’s not follow Elon Musk and his big dreams and get obsessed with his vision of the future because we can still do really cool things without joining the cult of Musk.

ZW: A hundred percent. I think we did talk about there were these lava tubes on the Moon that are maybe hundreds of times bigger than the ones on Earth, that we’ve never been inside. There’s no economic value of this. There’s maybe cool space base value, but I just want to pee. I know I’m broadly negative or whatever. But I’m not in any way against space exploration. You could debate whether it’s the best use of funding for science, but whatever, we have the funding, and it’s awesome. So, that’s all good. Where it gets dicey is when you talk about permanent populations, having babies and trying to declare a nation state,

PM: Then things really go off the rails. Zach, it’s been really great to speak with you. I would highly recommend that book for anyone interested in learning more about this because it’s fun to read, but it’s also super informative. Thanks so much for taking the time. I really appreciate it.

ZW: Thanks very much. This is a lot of fun.