Latest / Art of the Question / Why We Still Need Humans in Space - Prof. Ian Crawford - #34

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Why We Still Need Humans in Space - Prof. Ian Crawford - #34 · Art of the Question

• Julius Moorman: Yes. So, ⁓ Ian, ⁓ thank you so much for for coming on the show. like I said, I'm I'm very interested to talk ⁓ about the moon today. First of all, I was very curious to understand, have you always been interested in space? ⁓ well, yeah, first of all, thank you thank you for having me. Pleasure to be here. Yes, I've been interested in space for ⁓ pretty much as long as I can remember. I'm a child of Apollo in a way. I mean, I was seven in ⁓ July nineteen sixty nine. So I grew up with ⁓ people landing on the moon and it just seemed like you know, normal thing for people to be landing on the moon. And that was very exciting for a while and then not much has happened in the last fifty years. So, ⁓ well that's not quite fair, but one one might have hoped that we'd be a little bit further along in space exploration given where we were sixty years ago. So I've been interested ⁓ that was part of the reason. I ⁓ read a lot of science fiction as a young person and that also had quite a quite influence on me. And and last but not least, my late father was ⁓ interested in astronomy. I mean he was a dentist, but he he was interested in astronomy as an amateur level and and some of that doubtless rubbed off on me. So yeah, for all of those reasons I've been interested in space exploration for a long time. I can imagine, and of course you're very young when you're seven years old, but I can imagine that this must have been such an impactful moment on you that you probably still have some memories about that moment when we first landed on the moon, or is that a blur? Well, it's slightly a blur. I mean the the problem is you rewatch some of the old footage so many times you can't quite remember what was an original memory and what's been implanted. ⁓ since I I do remember being ⁓ got up to look to watch Neil Armstrong step on the moon. ⁓ and that that was a ⁓ I mean that was I would say w where it's a formative experience isn't quite sure. I mean my interest was there already. So like I said, it does kind of seem natural. Pe people are on the moon. So this is, you know, this is what people do. So I was it's sort of young enough to to dot not really see it as the sort of epochal ⁓ moment in human history that that actually with retrospect It it probably it probably was. Yeah. And you mentioned there ⁓ that obviously not much has happened. I mean we have been looking at the moon and and science hasn't exactly come to a total stop. But I do agree that I mean being on the moon and sending robots to the moon and and looking at the moon are are two different things. Now there seems to be some momentum again, which we'll touch on later. But why has it been such a long time? Why did we initially go to the moon during that era and why has it kind of died down after? Well, yeah, okay. Firstly, I should I should caveat what I said earlier. I mean a tremendous amount of space exploration has been done in the last sixty years. Right. I mean, ⁓ so I d I don't want to downplay that at all. It's been in many ways a triumph of human engineering, engineering and ingenuity and science, the things that we've been learning about not only the moon but the rest of the solar system through unmanned space exploration. I it I mean I I don't I don't think that should be downplayed at all. It's all it's all it's all fantastic. But a as regards why ⁓ humans haven't been back to the moon for fifty years, I mean there are there are several reasons, but the The the most important reason is is clearly that Apollo was a geopolitical project. I mean science we got a lot of science out of Apollo but but Kennedy didn't ⁓ didn't initiate the Apollo program for science. It was clearly a Cold War race between the United States and the then Soviet Union. So from that perspective, once you've won the race, what is the point of continuing? I mean not from a scientific perspective, but from a political standpoint. Especially given that the programme is firstly very expensive and secondly very dangerous. So the longer you keep it running, the more the more money you have to spend, despite having already won the race, and the greater the chance that someone's going to die on your watch ⁓ on the moon, which isn't gonna be an enticing prospect for any US president. So for these reasons, I think these are these are the these are the reasons Apollo came to an end when it did. But there's there is a subsidiary reason. ⁓ it has taken a long time for science to integrate all the knowledge that we learnt from the Apollo program, especially all the lunar samples. I mean, these have taken decades, and we're still not finished analysing them. Plus all the ⁓ geo f geophysical in measurements that were made on the moon. It took a long time to assimilate all of that knowledge. So for a while, you could argue that we've been to the moon, we've done that. Apollo's told us everything we need to know. So even from a scientific perspective, why would we want to go back? And it's taken quite a long time for the science community to realise that actually Apollo didn't tell us everything we needed to know about the moon. ⁓ Apollo in many ways opened up lots of new questions as exploration always does. You discover some things and you discover things you don't know. And then this poses new questions. And then gradually within the science community there's been a realization that actually, yeah, we haven't really finished the moon at all. And so there's in there's also a scientific case for returning to the moon. and that that's been developing over the last several several decades. ⁓ but I I do think I I mean in all honesty, the main reason we haven't been back to the moon is a lack of political will, because the US did win that race, so wasn't predisposed to keep running. Right. Yeah, and I can imagine that ⁓ it also helps that we or doesn't help, it depends on on how you look at it, ⁓ that We've made some significant improvements in in building more advanced robots as well. So, first of all, we won that race, or we, like I I I'm not even American, but let's say the the the the West, the West, the US won the race. They were the front runners in this race. ⁓ I mean, I believe even Russia shifted its focus on exploring different planets in the solar system, albeit ⁓ non-manned ⁓ mission. They believe they did many missions to Venus, for example, with some unmanned missions after that. I believe so I believe the entire focus shifted, but also we were getting better at building robots and building unmanned crafts. ⁓ is the d is that true or or do you think that doesn't really play a role? Well it is it it plays a role. Clearly it plays a role. But I I would say the Soviet Union, yes, having lost the race to the moon I mean both the US and and and and the Soviet Union continued their robotic exploration of the solar system, and you're correct that the Soviet Union had much more success with Venus and the United States had much more success with Mars ⁓ and and the outer solar system. But that was kind of going on in parallel with the human space flight program. I mean that didn't stop after Apollo. So the Soviet Union did pull itself back to low Earth orbit and developed a string of space stations in in Earth orbit. ⁓ having lost the race to the moon. And of course the United States did the same. Its human space flight program continued, but it continued with the space shuttle and the development of what ⁓ was Skylab as our first space station and then what became the International Space Station. So the human space activity has carried been going on kind of in parallel ⁓ with the robotic exploration of the solar system. It's just that it's been restricted to low Earth orbit and hopefully now we're going to extend back. beyond low Earth orbit. As we've already seen a start, right, with the Artemis II ⁓ mission round the moon earlier earlier this year. So it's true that we can build better robots. And it is true that there are places in the solar system you have to send robots, right? You can't send a human to the surface of Venus or to Titan or somewhere. Just it's just not not going to happen, probably ever, or certainly not in any realistic timescale. So robots are best suited to those environments. But I do think a strong case can be made that planetary surfaces where humans can operate, obviously we can operate on the moon, because we've demonstrated that. And we will be able to operate on Mars. And I I do think that planetary surfaces where humans can operate, there will still be a net added value of having human explorers, ⁓ in addition to robot explorers. ⁓ And there are multiple reasons for this, which I could enumerate if if you want. But I I I think it's a kind of a false dichotomy, humans or robots. I think in space exploration both have their place, and whether you would send humans or robots or both depends on where you're going to and what scientific questions you want to answer, gauged against the relative capabilities of humans and robots. And so the th th this is the calculation that needs to be made. Yeah, and it's exactly one of the questions I had for today. So I think it might be a good ⁓ yeah moment to to dive into those reasons. ⁓ what are the I mean, obviously there are obvious differences between robots and and humans, and there are obvious scenarios when we should use a robot over a human. For example, when exploring when the Russians ex explored Venus. To go back to that example, their robot lasted about 30 minutes at best, I believe. It was able to to s to shoot a a couple of photos, send it back to Earth, record some some audio, if I'm not mistaken, ⁓ which yeah, which gave us incredible footage. But of course, even the robot, given the the heat and the sheer Hell, hellish landscape of Venus did not survive long. So obviously, it makes sense to use robots in those scenarios and perhaps for scenarios where we haven't really explored yet. So Mars is a good example. We may send humans there one day, but it will help to understand the environment better if we send robots first. But what what are some of the things that humans At this point in time, humans can do that that robots are just unable to do? So I think there are several there are several things. There's ⁓ firstly, there's human versatility and the fact that humans can think, we can think on our feet. And we've had millions of years of evolution driving our ability to think on our feet. And part part of this ⁓ is the ability to ⁓ spot things that are important. Just out of the corner of your eye, spot something that's important and go and investigate it. ⁓ which robots ⁓ depending on their training model, aren't really trained to do. We can't got you can't really train even an AI system, perhaps we'll talk about AI later, because this is obviously a big new development. ⁓ even an AI training model, unless you've got access to an XA pl an extra a place where no one has ever been before, it's going to be difficult to get an AI. model to just recognize have the same kind of instinctive versatility that humans have, because we've had millions of years realizing that our survival might depend on something strange caught out of the corner of our eye and sort of take notice of it. ⁓ But partly it's versatility. And even versatility in ⁓ encumbered by a spacesuit. So the the geologist ⁓ Stephen Squires ⁓ Steam Squires ⁓ was the principal investigator for the ⁓ spirit and opportunity Mars rovers. ⁓ and so he's obviously ⁓ been familiar with robotic exploration of Mars ⁓ intimately. ⁓ and and and you might expect him ⁓ to ⁓ therefore think that these rovers are going to be much better than humans, because he was le led their development. ⁓ but ⁓ if you read his book Roving Mars, he's actually quite scathing about their capabilities. ⁓ he he makes the point that What his rovers could do in a in a Martian day, a perfect Martian day where nothing goes wrong, still what they can achieve in terms of planetary exploration a human astronaut in a spacesuit could achieve in thirty minutes. Sorry, it's thirty seconds. See a rock of interest, bend over, examine it, decide whether it's important or not, put it to one side to be sampled or not. It t it takes the current the current generation of rovers, ⁓ hours or days to make those kind of decisions that a ⁓ a a human geo a human geologist can just sort of sort of make instantly. So th there's the versatility argument. ⁓ there's also a ⁓ slight it may seem a slightly facetious point to make, but I I I do think it is it's it is it is it's important and often overlooked. If we send astronauts to the moon or Mars, then these astronauts are gonna want to come back. And this is important. We should bring the astronauts back. But as soon as you design a space mission that has to carry heavy human beings and all their life support ⁓ equipment and everything a and bring them back, you've suddenly designed a mission architecture that has a very generous mass budget, such that you can then the whole thing's engineered to ha of necessity to carry a large mass to the moon or Mars. And therefore fitting in as ⁓ a spare capacity for a few extra hundred kilograms of scientific equipment or returning with a few hundred kilograms of moon rocks. This is no longer a massive showstopper in designing the mission architecture because the mission is has to be so big it can accommodate these things. That was a key lesson from Apollo, I I I think. ⁓ so yeah, of course the the the the fact that the the missions are so ⁓ large because they have to take people and everything, this is what makes them so expensive. But having committed to them, they've got a much greater capability both for carrying scientific instruments and for returning samples, just because the scale of the activity is so much bigger than a little rover scraping around on the on on the surface of a planet. I I could ⁓ ill illustrate some some of these points by comparing ⁓ the efficiency of the Apollo astronauts with ⁓ the efficiency of the of the latest generation of Mars rovers. And bear in mind the astronauts were like fifty years ago with fifty year old fifty year old technology compared with the modern rovers like perseverance and curiosity, and indeed spirit and opportunity, ⁓ on on on on Mars. So consider Apollo seventeen, ⁓ which was the last Apollo mission. Apollo seventeen, the astronauts were on the lunar surface for about three days. And during that time they traversed a total distance of about thirty five kilometers with their lunar roving vehicle. Now you compare that to Perseverance. Perseverance has been on Mars for five years now, and it has just traversed about thirty five kilometers, thirty-seven or something. So the Apollo seventeen astronauts covered a distance in three days that it has taken five years for even a fairly large nuclear powered rover like Perseverance to cover on Mars. But then you compare the ⁓ the other aspects of the scientific productivity. ⁓ the Apollo 17 astronauts during their three days drilled the deepest core, drill core, that's ever been drilled on a body other than the Earth. I mean, it was only three meters, but compared to planetary exploration, that's enormous. Certainly bigger than anything. Any rover no rover on Mars has drilled any into the subsurface deeper than about 30 centimetres. And but in addition to that, this drill core didn't stay on the moon, it's come back to the Earth, along with 110 kilograms of moon rock. I mean that's an enormous haul, just Apollo seventeen, a hundred and ten kilograms. And currently we haven't got any rock samples returned from Mars. ⁓ if we're lucky, we'll we'll get we'll get a kilogram, half a kilogram in the in the early twenty thirties. But that that's still to be determined. And of course, but the reason we've got these minrocks is as I mentioned, they're having stick commits to sending the astronauts, we have to bring them back. If you're going to rely on r relatively cheap rovers to do all this for you One of the reasons they're relatively cheap is you're gonna once they've finished working, you're gonna l leave them there. And they're not coming back. And therefore you've then lost the opportunity to bring back rock samples ⁓ with them. I could go on about Apollo seventeen. I mean, during those three days, they also deployed the only active geophysical seismic survey that's been conducted on another planet. I mean, as they were driving their thirty-five kilometers around their landing site. which is place called the Taurus Litro Valley, ⁓ in Mare Serenatis on ⁓ on on the near side of the moon, obviously. They carried with them eight, eight explosive packages. I mean, it's just incredible. Eight ba eight eight small bombs basically which were carried to the moon ⁓ and deployed around their landing site. And then these explosive packages were exploded once the astronaut by remote control, once the astronauts had left, in order to provide seismic signals For the ⁓ seismometers to do a geophysics survey. Plus there was also a whole load of other geophysical instruments deployed. And you look at all of that, and it was all done within three days. With with nineteen sixties, basically a early 70s equipment. This this that's a tremendously productive three days as far as lunar field geology is concerned on another planet. And and the rovers have not have not approximated it yet. Of course they may. Artificial intelligence may become a thing and the rovers may be the the robots may be made humanoid instead of on wheels. And everything. And and you could imagine them becoming more efficient. But as things currently stand, I mean, I th I do think the Apollo missions demonstrate that human exploration of other planets, although it is clearly expensive, is also very efficient. Yeah, and it's those are incredible examples. Honestly, I I had no idea that they were so much more efficient, but I think it's a very good argument as to ⁓ why we should continue to pursue manned missions. You mentioned humanoid robots there, and it's something I wanted to touch on as well. Because obviously there's multiple companies currently working on humanoid robots, which are powered by artificial intelligence systems. And if you break it down how they work. You can now take a picture with your phone and then you can upload it to ChatGPT or Claud or whichever AI model you're using and it will kind of understand what it's seeing, right? So if you take a picture of of a table and you put a glass at the very edge of the table and you ask, hey, what is likely to happen next It will tell you the glass may fall off, which is, of course, an incredible leap in technology compared to what we have had three to four years ago. However, robotics and and letting a robot loose in the real world is still incredibly complex. And if we're looking at why Tesla is currently why why Tesla has managed to even have self-driving vehicles on the road is because they had millions of vehicles continuously recording every possible scenario and then train their AIs based on all those different scenarios and now it looks like magic and now they are able to drive through the streets of New York. and Las Vegas and every other busy city ⁓ they are currently allowed in. So that's again an incredible leap in technology. However, it still doesn't solve the training data issue we have for everyday tasks. I mean, I believe Elon is currently working on gathering data from like regular computer workers. So ⁓ any task we are now doing on the computer may one day be automated as well. And it's something that perhaps a combination of humanoid robots and and and computers itself can do. But still if you have a humanoid robot on the surface of a different planet. yeah, we don't really have a lot of training data for those scenarios and I don't see any possibility at this point how we can generate enough trustworthy and high quality data in order to just let humanoid AI robots lose on a different planet and have them operate in a completely functional and and safe, fruitful way. So, I mean I I I I agree and and partly it's partly it's because the point we touched on earlier is that how do you provide training data for a place that's not been that's that's been unexplored? I mean the whole point of exploration is to is to discover things that are not known yet. So obviously the things that we do know, we think we know, we can obviously train, but the the discovery of the unexpected, I'm not I'm I'm yet to be convinced that ⁓ that that that that r the artificial intelligence is gonna be really helpful with that. But but perhaps I'm wrong. Perhaps you could train it to spot the r the unexpected. But the the other thing that I'm slightly concerned about with artificial intelligence on on other planetary bodies is where the energy comes from. I mean the the the I mean like I mentioned the Perseverance Rover is nuclear powered. It's powered by a ⁓ a radioactive isotope thermoelectric generator, which is basically a ⁓ container of plutonium salts and then the the this gets hot as the plutonium decays and thermocouples around the plutonium core convert the heat into electricity. But that that produces a hundred and ten watts. Now you don't get much artificial intelligence for a hundred watts. I mean I I I I I I I mean I I I don't I don't know but I think you need probably hundreds of watts or kilowatts, depends how much artificial intelligence you need currently, ⁓ for a really capable AI system. So unless you've got a large energy source on Mars, then you've got to ask the question where is this where's the energy gonna come from to to maintain ⁓ a a really capable AI system? Of course you can have the AI on the earth ⁓ and make decisions and beam them up. to the ⁓ up to the the robot on Mars, but then you've immediately got the latency problem. I mean it can take twenty minutes to get a signal from the Earth to Mars and twenty minutes back. I mean that is the extreme. It can be as little as as as four minutes each way, depending on where Mars is in its orbit. But in any case you've got this large latency which is going to greatly reduce many of the advantages, the purported advantages of AR. if you have to keep your AI system on the earth because of this long time delay to and fro. Whereas a human being on the surface would, as we've discussed, be making their decisions sort of instantly in in real time. ⁓ having said all of this, I I suspect it'll pan out to be a balance. I mean obviously artificial intelligence is going to have a role in space exploration, and so is robotics. So I do think it's gonna I do think it's a false dichotomy, like I said, to ⁓ make it an either or thing. I think as we explore the solar system I can see good reasons for having both humans and robots. ⁓ Yeah, no, I agree. ⁓ I th I think I I I also don't wanna present it as as an either or. I think it's great that we are creating humanoid robots to to explore space alongside us. ⁓ but I'm also happy that ⁓ interest in in going back to the moon is back. because it's it's exciting and it's fun. And You mentioned earlier in our conversation that we initially thought we figured out the moon and that there was not much science to be to be done anymore, but that part of the reason that we're going back now is that we apparently understand now that there is still a lot more to learn about the moon. So why are we going back right now? What prompted this return to the moon? Well, I I do think it's important to again separate the scientific reasons. I mean, I'm happy to enunciate all the scientific reasons. I think we need to return to the moon. ⁓ but of course there's also a geopolitical aspect to the Artemis program. I mean, there is new geopolitical competition in the world, this time between principally the US and China. But not only though, between the US and China. I mean, one of the things that's happened in lunar exploration over the last twenty years. Is that many countries in newly for space develop developing countries developing their space capabilities? So European Space Agency, ⁓ India, Japan, Korea, ⁓ they've all realized that if you want to demonstrate your space capability And Mars is too far away, then the moon is the only show in town, really. And part of this is driven by science, but part of it is also driven by geopolitical competition and national ⁓ prestige. So I don't I think it would be naive to claim that although I I'm I'm gonna give you in a minute, if you want, a whole long list of the scientific reasons for going back to the moon. I'm not I'm not I'm not so naive as to think this is the end this is the main or only reason. But but still I can see a great many scientific benefits. of a a human return to the moon. Yeah, no, I I'm think I think both are interesting. I think both the scientific reasons are interesting as well as the the geopolitical reasons. And I'm in a way happy that it's still seen as prestigious a prestigious feat to to go to moon. And if that what it if that's what it takes to drive manned space space exploration further. Then so be it. At least that's my personal ⁓ opinion. But I'm also very interested in the scientific reasons. So ⁓ please. Okay. Well I think the main th th there were s ⁓ at least three broad categories, broad scientific categories of why ⁓ why we want to go back to the moon. And I think the Apollo program provide the ⁓ the background knowledge as to why we've come to realise these things. But Apollo didn't answer all of these questions, in part because there were only six successful Apollo missions. They all landed on the near side of the Moon. They all landed at roughly, well, quite low latitudes on the near side of the Moon. So immediately it's clear the geographical coverage is not very representative. So we ha no no Apollo missions landed at high latitudes or the poles or or or on the lunar far side. ⁓ so since then there have been some robotic missions. ⁓ well only Chinese missions have landed on the far side so far. But so but the geographical coverage has been expended somewhat expanded somewhat since Apollo by robotic robotic missions to the Moon. I think what the what what what we've learned, the three broad categories, are one is the Moon is a ⁓ a small planet, obviously, a small planetary body, which means it's cooled down ⁓ long ago and has been geologically not active for billions of years. And this is part of the things that we learnt from Apollo. So that at first sight makes the moon sound very boring. It's if it's geologically dead, then why is it so interesting? ⁓ but the answer is it's interesting because it's like a time capsule. It's an example of a planet ⁓ whose early evolution is still preserved at the present day, four and a half billion years after the solar system formed, ⁓ because it hasn't had all the active geological processes like plate tectonics on the earth or atmospheric. it doesn't have an active hydrosphere or biosphere or anything that's kind of destroys rocks or buries or buries them. ⁓ and it's a geological processes which bury rocks, namely volcanism. Yes, it had these in its early history, but not for billions of years. So the consequence is the c the near the current currently accessible surface of the moon provides access to what the kind of geo geological processes that all the rocky planets were going through shortly after they formed. It's just the moon then shut down and so it's preserved this early state. Whereas more geologically active planets like the Earth and Mars have largely ⁓ and the Earth especially, Mars is kind of intermediate, have kind of ⁓ lost this early the record of the early what they're what they were like immediately post formation. So from a planetary science point of view, the surface of the moon provides this. So that's one reason. the second reason is ⁓ kind of relatedly Because the ⁓ because the moon has no erosional processes and it has no atmosphere and for most of its history it's had no magnetic field. ⁓ things coming in from space, everything from meteorites to ⁓ charged particles from the sun and and the galaxy, everything coming in from space is implanted into the solar the surface the lunar surface, which is like a dusty pulverized rock layer called a regolith. And so the lunar regolith ⁓ has preserved all these Everything that's been falling on the moon for billions of years. So it too is like a museum. But this time it's not a museum of the early history of the moon. That that information is in the moon rocks. But these lunar soils are a history of the is the space environment of the inner solar system, especially obviously the Earth environment, because the Moon's been orbiting the Earth all this time, of things that have been going on which we might like to know about, like how active was the sun in the distant past. Has the solar system ever been close to exploding stars as it's wandered around the galaxy? ⁓ there will be records of all of this in in the lunar soils if we can access them. So so that's using the moon as a ⁓ a kind of museum of solar system history. And then the third the third broad category is using the moon as a platform for further astronomical observations. So the far side of the moon ⁓ is by far the most radio quiet place anywhere in the solar system, because it's permanently shielded from the earth. And during night time on the far side of the moon, it's shielded from the sun. So it's it this this means the most radio quiet place in the solar system, probably certainly the inner solar system. And so it's an ideal location for radio ⁓ radio telescopes. So this this would be a using the moon as a platform for radio astronomy. ⁓ that's the far side. We've also realized that at the lunar poles there are craters that the flo floors of craters which never see the sun because the sun is always on the horizon at the lunar poles. ⁓ and so these craters are very cold and very dark, and these are also potentially quite useful places for p putting infrared telescopes, and also, as it turns out, gravitational wave telescopes. So th these are examples of using the moon as a a platform ⁓ for for for astronomy. So those are the three broad categories. And then, you know, within those there are lots and lots of more detailed studies we could talk about, but probably don't have time for. But broadly that's the scientific the scientific justification for going back to the moon. Right. And in order to do ⁓ some of that science, for example, the ⁓ equipment that we would need on the moon, but perhaps also for some of the other studies. I believe it is the plan to build ⁓ lunar bases as well and eventually send humans to be ⁓ on within those bases similar to what we currently have ⁓ with the International ⁓ space station where astronauts Come and go ⁓ for for stay for a couple months and then head back home. That is the eventual goal, I believe, from NASA, but also from China, perhaps the EU. I'm not sure about that one. Is that necessary to explore this science, or is that ⁓ also or ⁓ perhaps even more driven by the the political ⁓ race that is again ⁓ going on? So it's both. But I d I do th I do think from a scientific point of view, yes, our Moonbase would be a tremendously enabling piece of infrastructure on the Moon. I mean the best analogy I think is not so much the ISS, but the Antarctic, the research stations that we have in in Antarctica. So the the the Antarctic research stations like ⁓ well Concordia, that's a ⁓ European one, and McMurdo and Amundson Scott, those are these American bases. they they provide scientific infrastructure that enables the exploration of the Antarctic continent that otherwise would not be feasible. So these bases, every year from these bases, scientists go out into the field in Antarctica to Cover a whole range of sciences. I mean astronomy is a casing point. There are telescopes, radio and infrared and neutrino telescopes in Antarctica that wouldn't be possible without these bases to provide infrastructural support. There's the astrobiologists who travel out to the dry valleys in Antarctica because they're Mars analog locations. People go to Antarctica to search for meteorites because meteorites get trapped in the ice and then can be relatively easily identified. There's geologists, obviously doing the geology of Antarctica, there are the bio in the case of Antarctica, well they're not not obviously on the moon, there are all the biological sciences, zoological sciences, and also the meteorological sciences. I mean, this is how we studied the ozone whole. All of these sciences are supported by the fact that there are permanent bases ⁓ which provide scientific infrastructure. And I think the same would be true on the moon and ultimately on Mars. The Antarctic style research stations, even if part of their justification is geopolitical, will enable a lot of science which isn't going to be possible otherwise. So I would see them as very enabling pieces of scientific infrastructure. And incidentally, many of the reasons these bases are in Antarctica are for geopolitical reasons as well. ⁓ is because despite the Antarctic ⁓ treaty system, which has put national claims on Antarctica on hold, ⁓ in order to have a say in the governance of the Antarctic Treaty system, ⁓ you have to have boots on the ground in Antarctica. So there are reasons that nations maintain these these research stations in Antarctica that do go beyond their scientific utility. But they are scientifically useful nonetheless. And that this is is the analogy I think I would make. ⁓ for the main. Yeah, it seems to be a recurring theme then that we ⁓ need need boots in the underground in in those scenarios. ⁓ what about the technical feasibility of building a moonbase? I mean, obviously we currently do not have a moonbase, multiple nations are working on it. Is it something that is with the technology we have today? Absolutely feasible, or are there still some advancements necessary in order to build something like that? Well, I think it is to will be technically feasible, but there are still some unknowns, or at least there are known unknowns. I guess whether they're also unknown unknowns, this is why we explore and we'll we'll we'll find out. But based on what we currently know. I mean, obviously the main the main limitation is just the sh the sheer cod difficulty of getting a lot of stuff up to the moon, right? So this does require a large commitment in launch capabilities, getting a lot of mass to the moon. ⁓ but if given that you can do that, then I think with the main ⁓ the main problems that we would know about, ⁓ we do know about is obviously the radiation environment on the moon is extremely ⁓ hazardous, at least it would be for long stays. So any moon base will require radiation protection, ditto protection against micrometeorites, because the moon doesn't have the atmosphere that the Earth does. So radiation, protection from radiation micrometeorites, yeah, this is a known issue. But then it's not a particularly hard issue to solve. I mean, the highest energy charged particles from the sun, which occur when the sun has solar flares, these are the most dangerous ones. Or the high energy ⁓ cosmic rays that come in from the galaxy. by the way, th those are part of the scientific record we'd like to dig up in the lunar soils, these high energy cosmic rays coming in from the galaxy. But you don't want them going through your astronauts. ⁓ on assembly micrometeorites. But the point is you can the shielding against these only requires a meter or so of shielding. And on the moon ⁓ there is plenty of shielding material available. It's the regolith that we've talked about. So you would need to have your habitat covered by a metre or two of regolith, probably to protect from the solar wind and the the the the the the cosmic rays and the micrometeorites, ⁓ especially. ⁓ so you'd be looking, I think n I not quite subterranean bases, but they could be on the surface, but they would need covering. And the obvious cover would be a meter or two of lunar lunar regolith. That would also keep the temperature ⁓ the temperature much more stable inside your habitats. That's the other problem with the lunar environment. Is that unless you're at the poles where the temperature is very cold but pretty stable, if you're at an equatorial, near equatorial site on the moon, there's this huge three hundred degrees Celsius temperature variation every lunar day, from like plus one hundred and twenty at midday to about minus a hundred and eighty just before sunrise. And that that is also g obviously gonna cause ⁓ problems on equipment as things expand and contract under this diurnal temperature range. But shielding with the the the the the the the the the same shielding that you've employed to protect yourself against radiation is also gonna shield against these extreme temperature fluctuations. I think the b the big unknown ⁓ the biggest the biggest unknown is the lunar dust. I mean the lunar regolith does contain a fraction that is extremely Extremely fine-grained, micron-sized particles of ground-up rocks. These are hazardous. They'll be hazardous if they're inhaled. And they will also get into equipment and where they will start wearing down, wearing things down that you don't want to be worn down, like ⁓ airtight seals in airlocks and spacesuits. And so mitigation from the dust. I mean Apollo didn't last long dust was also a problem in Apollo, even after three only three days. But for long duration stays on the moon, mitigating lunar dust is gonna be a a learning curve. We're gonna have to go up to go go up. And I I I I doubt I doubt it's technically infeasible to deal with, but it probably is the biggest, the most concerning known un known unknown that we can all see is is the effect of lunar dust and how to mitigate against it. Yeah, and let's say we we figure we figure figure it out to to we we overcome all these hurdles and we manage to build a a lunar settlement that is shielded from the radiation and the the micro meteorites. How long can astronauts ⁓ likely stay at the lunar surface for yeah uninterrupted amount of time? So I think this is to be determined. a lot would depend so this would be learning as we go go along, right? ⁓ a lot would depend on the effectiveness of the radiation shielding. Bearing in mind that astronauts outside of a covered habitat would be exposed to the background cosmic rays. That that will impose a limit, but I don't think it's a very severe one. ⁓ but they would have to be c ⁓ seek cover if the sun if there was a major solar flare on the surface of the sun, because that can could result in lethal doses of radiation to an unprotected astronaut. But with the caveat that that's ⁓ under control, ⁓ and the dust inhalation problem is as under control. I mean, but these are things that we need to learn as we as we go. I mean your your next biggest thing is the is the low gravity. So obviously the ⁓ the the surface gravity on the moon is one sixth of what it is on the Earth. And the Apollo missions were not there long enough for this to have an obvious effect. But if someone was there for a lot on the moon for six months, this is something that does need studying. Obviously, we've got a lot of expertise now on ⁓ the effects of zero gravity on human beings thanks to research in the space station and whatnot. And we know human beings can survive in the space station for a year or so. And presumably the moon is less bad because there is some gravity. not not no gravity. But the but what we don't know, because just haven't had people on the moon for long enough to study, is is it like a linear a linear effect that the gravity is you know I mean a sixth of a gravity is one sixth of an Earth gravity, but it's infinitely more than zero gravity. So just where does the biological cutoff happen for this to become serious? Is is is one sixth of a gravity Would it pose long term health risks or not? And we don't know. But it's unlikely to be as bad as zero gravity. And so I think that the that it's unlikely to be a major limitation for how long people can stay on the moon. Certainly if you're talking about like what is mo mo more most likely based on both the ISS and the Antarctic base analogies, is people on ⁓ cruise on something like six month rotations. I can't myself see the gravity being a serious issue there compared to the dust and the radiation. But but it does need studying. I should say, ⁓ we haven't touched on it yet, but a lot of these things if we do want to send humans to Mars in the more distant ⁓ future, we are also gonna have to learn about these things, right? We haven't done Mars too is a dusty environment. The dust is different, it's probably much more reactive, the Martian dust than the lunar dust. But so there's there'll be a dust mitigation problem on Mars. The radiation environment on Mars is also very bad. Not not as bad as the Moon, but it's it's also very bad. And the gravity is also low. I mean it's more than the Moon, but it's ⁓ less than the Earth's. So learning how to cope with high radiation, dusty, low gravity environments, we'd need to learn how to control these things if we ever want to send people to Mars. But the difference is The moon is only three days away, so if things go really ⁓ wrong on the moon, it is possible to rescue people from the moon. Once you've committed them to Mars, then it is not. I mean it takes eight months to get to Mars, but having got to Mars you can't just turn around and come back. Most of the trajectories would require you to be three hundred days or something at Mars before the planets are back in the right configuration to return, and then it would be another eight months back. Well it becomes really important to learn how to cope with these ⁓ these issues of learning on learn learning how to live and operate on a hostile planetary surface ⁓ before we send people to Mars and and the Moon is the obvious place to learn how to do that. While of course, at the same time, it's not just that the people on the moon be preparing to go to Mars, they'll also be looking at the lunar rocks, digging up the ancient soils and setting up radio telescopes So it could be learning a lot about the moon as well. But in addition to that, I think it probably is important preparatory work for sending humans to Mars or anywhere, you know, more distant in the solar system. I think it makes perfect sense. It's a logical stepping stone and it would be pretty Yeah. I I don't know if it would be smart to just send out humans to ⁓ to Mars ⁓ when we haven't even figured out the moon ⁓ completely yet. So once you I think it'd be Yeah, I mean I think it'd be very irresponsible for multiple reasons. One one is we just haven't learned how to handle all these things like the radiation, the low gravity and everything, which we can learn on the moon. ⁓ but the there are there are more significant issues. I mean for Mars we still don't know that Mars definitely doesn't have a biosphere of its own. So before we jump in with human I mean, probably it doesn't. The consensus is at least the near surface environment of Mars probably is is not inhabited. But we actually don't know that definitely yet. So probably we should we should l we should get a definitive answer to that as insofar as we can before we commit humans to Mars. And that probably a start at least can be made with robotic spacecraft. So I d I do I do think it comes back to our discussion earlier. ⁓ I do think the robotic exploration on Mars Can and should continue robotically for probably many, many more ⁓ I'd say decades, but at least a decade or so, in parallel with the development of a human space capability on the moon. ⁓ such that when when when when we're ready ⁓ to send people to Mars or we will reach a point where we are ready, we'll learn enough from our robotic exploration of Mars to say yeah, the ro so to just make the judgment Mars is probably not inhabited. By its own microbes. And we've probably learned enough as much about Martian geology and whatnot as we can with robots. And now is the time to send humans. And maybe maybe that point will be reached by the middle of this century. But in parallel to that, we'll be ready to do we'll be ready to send people to Mars if we built up this human spacefaring capability on the moon at the same time while we're exploring Mars with robots. So to my mind, this is the most irrational way. I mean, if you were trying to design a solar system exploration strategy, this seems the most rational one to me. ⁓ but not not everybody agrees. Wha what would be the consequence if we do happen to discover ⁓ biology on Mars? Would that stop us from from pursuing our our plans to have humans on on the moon, at least for the foreseeable future, or because I can imagine it would be even more interesting to go than on on Mars, yes. Well I think this is this is the there will be there are big questions there. And the the ultimately political questions ⁓ in the in the broadest sense. so you can see this this can be this can be cut several ways. If we were to discover life on Mars You could argue that we can't send humans to Mars because we will disturb the Martian life. And indeed it might we might risk since since the people we send to Mars are probably going to want to come back to the Earth, we might also risk back contaminating the Earth with Martian organisms. So probably one wouldn't want to do that. And and so that would require pretty strict sterilization protocols, at least for returning astronauts, that might not be compatible with. Sending humans to Mars. I mean, I I I don't know. It would be a big issue. ⁓ but then you've got there's also behind lurking beyond that, you've got this huge ethical question. I mean, if Mars has its own life, then who are we to suddenly transplant Earth life to Mars? I mean, Carl Sagan ⁓ made the point, and I think he was right, ⁓ that if we find that Mars has life, then Mars should belong to the Martians. I mean, it's not humans shouldn't just come in and appropriate it. Having said that, you're also right. If there turns out to be life on Mars, it may be that to properly understand it, its habitat, its evolutionary history, it's going to require such a big program of Mars exploration that little rovers ⁓ aren't going to be able to cope, and so maybe it would be a case for sending humans to Mars. So then the but then the question is and this is the political question, who decides? Right? Does a certain a certain does a certain billion trillionaire Shabby Nameless, who has a big rocket company. Does he decide? Does the President of the United States decide? Does the Secretary General of the United Nations decide? Who decides? The point is we don't that we're going off on a different ⁓ tangent here. It would be a different podcast, I think. ⁓ but the world does not currently have the kind of global political institutions that we will actually require to make these kind of decisions. ⁓ and I think there's a case for case for developing them. ⁓ so so I so I don't know. I yeah and you can see arguments either way. I mean I I personally am with Carl Sagan that if we find life on Mars then probably we should at least have a moratorium on human missions to Mars until we've learnt as much about it as we can using sterilized robots. ⁓ but there will be arguments on the other side. I mean I I had this argument ⁓ with a taxi driver once when ⁓ he was asking me, you know, what do I do? And I'm an astronomer, do you believe in life on Mars? And you know, how the conversations typically start. ⁓ and I I I made this point that if there's life on Mars, we probably shouldn't be aiming to colonize Mars, ⁓ because we might destroy the Martian microbes. Because obviously it will only be microbes. I think we know enough about Mars to know that it would only be microbes. And his argument was, Well, okay, but they're only microbes. You know, you kill millions of microbes every time you wash your hands and brush your teeth, and that's why we do wash our hands and brush our teeth. So So, you know, why are these microbes so important? Humans are more important than microbes, so if we need this planet for ourselves, you know, we shouldn't let the microbes stop us. So and there will be powerful voices that will agree with the taxi driver. ⁓ you know, in addition to those who see it from a more ethical perspective. 'cause I would argue, perspective, that we shouldn't be taking over somebody else's planet. So then it boil given that there will be these two powerful arguments on both sides of this debate, it does boil down to a political question. ⁓ who decides? And currently we don't actually have a political infrastructure that will let us make a the decision that would everyone would view as legitimate. ⁓ as far as I can see, I mean so we've gone off we've gone off the the ⁓ It's okay it's okay. But that's There are these deep questions lurking in the future. The good news is though they don't apply to the moon. The moon is not inhabited. I mean cannot be inhabited. I think we can be very confident about that. So these these issues that will will will apply downstream for Mars and not issues as regards the exploration of the Moon, which is just another reason why we should be starting with the Moon instead of rushing to Mars. No, I think it was a super interesting tangent and ⁓ but you're right to say it might be might be a conversation for a different day. But I'm I'm always deeply interested in ethical problems like this because I do if we're if we're talking about the the the the anonymous man with the the trillionaire ⁓ with the with the rocket company I believe his argument is that we his mission, it's the entire mission of SpaceX is to preserve consciousness in the universe, right? And then one can argue whether microbes are even conscious or not, but if we assume they're not as conscious as humans are and that there's a certain hierarchy, ⁓ yeah, there could be a case that we should try and and not put all our eggs in in one basket for God forbid something were to to happen with Earth, which is inevitable, I I feel like. But yeah. So I dunno I don't disagree. I mean, I think this is this is one of the powerful arguments on the on on the the the pro colonizing Mars ⁓ side of the argument. So what interests me really is is who's going to adjudicate between these arguments. I mean you could Just to be a devil's advocate, yeah, you could say the microbes currently are not sentient on Mars, assuming there are any. But two billion years ago the Earth was inhabited only by microbes and none of them were sentient. But if some alien space species had come in from outside and taken over the Earth two billion years ago, then we wouldn't be here. And the the two billion year old Earth microbes would never have had their chance to evolve into sentient life forms. So we wouldn't know that if we were to intervene on Mars, we might be precluding some enormous future for the Martian life forms, bearing in mind that on the longest time scales, as the sun as the sun gets brighter, ⁓ the earth is going to become uninhabitable and Mars is going to warm up. So so Mars will have a future, where if it does have indigenous life, you know, it might evolve to a greater degree of complexity than what it is now. Assuming there is any. So who are we? Who would we be to put an end to that Martian evolution? Bearing in mind that we would not have wanted ⁓ anyone ⁓ to interfere with our evolution two billion years ago because we wouldn't be here if they have. So I mean that that's the ethical argument. Yeah. No, it's it's deeply deeply fascinating. If we if we if we go back ⁓ to the moon, ⁓ finally some some some final questions I have regarding ⁓ lunar exploration. You mentioned earlier that one of the challenges is ⁓ getting stuff to the moon. ⁓ we're currently at least ⁓ SpaceX is is building bigger and bigger rockets, so it seems that we will be able to to send more stuff to the moon pretty soon. How much do we need though? Because sometimes I read articles that seem to imply that the moon is ⁓ very ⁓ rich and that it has a lot of ⁓ yeah materials to to build and and we can even build structures from the materials that are already there. ⁓ there seems to be water on the moon as well ⁓ in in some of the poles. So a lot of the the building blocks we need in order to build certain basis or or or other things we might need are there. But what are the some of the things we should absolutely carry and and have no way of building there? Well it's going to be it's gonna have to be bootstrapped from nothing because currently there is nothing on the moon. ⁓ that's an industrial s d an industrial capability on the moon where th where you can use the moon's resources to build things in situ. So ⁓ I think we would start with the water. I mean the water is the low hanging fruit. There probably is water in the permanently shadowed craters at the lunar poles. And therefore, if you're setting up a moon base, ⁓ I mean water's obviously a very useful material 'cause it obviously we need the water if we're gonna have humans living on the moon for all sorts of purposes. But then the water is ⁓ splittable into hydrogen and oxygen. The oxygen's obviously also very useful. The hydrogen's also useful as a as a rocket fuel. ⁓ and so water's a very useful material, but a cubic meter of water weighs a thousand kilograms. So if you've got a local source of water, you can save an awful lot of rocket launches not transporting water to the moon. So that makes a lot of sense. So you'd start with that. Further downstream, yes, all the common elements iron, aluminium, magnesium, silicon, they're all there in the in the lunar rocks. But to extract them, of course, requires a bit of industrial capability and industrial infrastructure. It takes quite a lot of energy to take a rock that contains iron and ⁓ And extract these atoms from them from the minerals that they're in. So that requires quite a lot of energy. and ul but ultimately if you ⁓ the moon needn't be short of energy though, because the and this in sunlit areas, the unadulterated sunlight is extremely intense. ⁓ but and if you needed more you could supplement it with nuclear power sources without the same kind of environmental problems that we have on the earth with nuclear power sources. So energy ought not to be a problem on the moon. ⁓ and then yes, it does have all the common or so if you need iron or titanium or aluminium to make alloys to construct the moon base or silicon to make solar panels, these materials do exist on the moon, but you can't get them from a standing start. I mean currently the moon is just a surface of the moon is just a dusty desert. There is nothing there. So until we build up a capability in Sitchi, we'll have to bring everything from the earth. ⁓ But I ⁓ and it'll be a sliding scale. I think we'll start by bringing everything from the earth, but then eventually we'll start using water from the moon and then later on we'll start extracting the common metals that we might need for construction purposes. But anything really high tech, like the ⁓ like the GPUs in the artificial intelligence systems that we're probably gonna have to bring, right? or or computers or whatnot. Obviously we're a if you if you imagine the kind of infrastructure it takes to build a computer or anything comparable. And not just the sophistication of it, but the clean rooms. The sophistically is not a clean environment. Building like a clean room, ⁓ where and and thus where you could build something really sophisticated, like a computer core or something. I think for a long time those high tech products are gonna have to be brought from the earth. Yeah, no, that makes sense. But it it does seem like as soon that it will get easier with time as soon as we the more stuff we get there the the easier it will be to ⁓ to build stuff there. It will be a snowballing a snowballing bootstrapping exercise starting small and gradually building building upper capability. Yeah. Well, Ian, we've already ⁓ been been doing this for for an hour and I could go on forever because this is ⁓ endlessly ⁓ fascinating to me. ⁓ is there anything we haven't touched on that you think is important for for our discussion today still? Yeah, I I wanted to come back to the geopolitics. Yes. So I think the geopolitics, ⁓ obviously in a sense, this looks bad. The net like the Cold War competition that drove Apollo. I mean, yes, you got Apollo out of it. But it was kind of not really desirable to have confrontation between superpowers if you can avoid it. And now we're seeing a new competition arising between the US and China. I think there is a more positive spin on the geopolitics of space exploration, and that is space exploration can be a natural focus for international cooperation, as we see with the space station. So I think a what we should be trying to do is to make Cooperation, a key geopolitical driver for space exploration, rather than competition. ⁓ so this may this may seem naive, but I think ⁓ it it it it it did work with the space station in that the s the ⁓ following the collapse of the Soviet Union, Russia was brought on board to ⁓ as a partner on the space station and Europe and Japan. ⁓ and it's true that China was excluded, and that was probably a geopolitical mistake because had China been included on the space station, we might now be looking to have an international space station including China and therefore building on that an international moon base that included both the US and China. And that would be better than having two moon bases on the moon. One American s ⁓ and its allies plus a China a China moon base. I mean Karak lands at a sip si both of these moon bases are very close together near the South Pole of the Moon. Partly 'cause that's where we think the water is. ⁓ and it doesn't really make much sense. ⁓ all that duplication of efforts, having two moon bases next to each other. But worse, if you have two moon bases next to each other, then you're setting yourself up for conflict. You're setting yourself up for one party to ⁓ start complaining that the other party's treading on its toes or encroaching into its space, and all of a sudden You've got a South China Sea situation developing at the south side of South Pole of the Moon. And we can foresee it in advance. So since we can foresee it in advance, I think we should be working to avoid it in advance and making the case that actually what we want is one moon base, ⁓ and use international cooperation as a c as a geopolitical ⁓ driver for the future exploration of the well, the moon in the first instance, and and then the rest of the solar system. So ⁓ yeah, I I would I would like to end on on that thought. I think space exploration is a it does I mean it's not a panacea, obviously. The world has many problems and there are many political difficulties, but space exploration has the advantage that it's all it's obviously always going to be a very high profile activity. Setting up a moon base is gonna be a high profile activity that everyone on the world is going to is going to know about. So if they can see all the nations of the world cooperating in this high profile, dangerous environment on the moon, making in a common a common project to make a common moon base. I mean this would be a good example to the world, wouldn't it? At a time when arguably we we need more examples of international ⁓ cooperation rather than conflict. So yeah, so you can say that I'm naive, but I I think that in in a sense Even though I can see the immense scientific benefits of returning to the moon, I can see ⁓ some of the geopolitical benefits ⁓ potentially could be even more important, ⁓ provided we play our cards right. I believe, yeah, I you you call it naive, ⁓ s some may call it hopeful, but also I believe that most of the astronauts and and people from these different space organizations, all the scientists and engineers, They I believe they love to work together. It's it's mostly the presidents and and people higher up that are preventing those scientists and engineers from from working together. But it is my understanding at least that most people in the space of the respective space organization ⁓ would love to to join forces ⁓ on project. Yeah, I'm I'm sure that I'm sure that's right. Yeah. Finally, ⁓ in w ⁓ where can where can people go if they if they wanna keep up with your work? You mentioned earlier that you were working on a book as well. Is that something ⁓ to be ⁓ to be expected or or where can people do you have a website where people can learn more about your ⁓ your science? Well yeah, yeah. All right. All right, I'll make sure to ⁓ to put it in the in the show notes. Thank you so much for today. I had a great time. This was incredibly interesting. And yeah, like I said, I I could go on for for many, many hours, but ⁓ yeah, maybe we'll just have to run it back in the future. For now, I'd like to ⁓ thank you so much, ⁓ Ian. This was great.