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The Value of the Moon

Season 1Episode 114Oct 18, 2019

Samuel Lawrence, planetary scientist and lead lunar exploration scientist, discusses what we’ve learned about the Moon and some of the more interesting questions that we hope to answer when humans return in the Artemis program. HWHAP Episode 114.

Value of the Moon

Value of the Moon

If you’re fascinated by the idea of humans traveling through space and curious about how that all works, you’ve come to the right place.

“Houston We Have a Podcast” is the official podcast of the NASA Johnson Space Center from Houston, Texas, home for NASA’s astronauts and Mission Control Center. Listen to the brightest minds of America’s space agency – astronauts, engineers, scientists and program leaders – discuss exciting topics in engineering, science and technology, sharing their personal stories and expertise on every aspect of human spaceflight. Learn more about how the work being done will help send humans forward to the Moon and on to Mars in the Artemis program.

For Episode 114, Samuel Lawrence, planetary scientist and lead lunar exploration scientist, discusses what we’ve learned about the Moon and some of the more interesting questions that we hope to answer when humans return in the Artemis program. This episode was recorded on August 28th, 2019.

Houston, we have a podcast


Pat Ryan (Host): Houston, We Have a Podcast. Welcome to the official podcast of the NASA Johnson Space Center. This is Episode 114: “The Value of the Moon”. I’m Pat Ryan. On this podcast we talk with scientists, engineers, astronauts and other folks about their part in America’s space exploration program. And today we’re going to talk about the target of a lot of our current efforts: the Moon. NASA’s Artemis program is focused on returning American astronauts to the Moon by 2024 through the use of the Space Launch System rocket, the Orion Spacecraft, the Gateway Lunar Outpost and a new lunar lander. And to do so in a sustainable way, that is to go to the Moon to stay, to learn how to support astronauts in that environment and in the process get ourselves ready to go on from there to Mars. As a part of that mission, we mean to make the best use of the natural resources on the Moon, and that’s very different than what the Apollo program set out to do 50 years ago. It also prompts an echo of President Kennedy’s question: why the Moon? Well today we’re going to start scratching the surface of answering that question by talking to the self-described cheerleader-in-chief for the Moon. Dr. Samuel Lawrence is a planetary scientist in the Astromaterials Research and Exploration Science Division here at the Johnson Space Center in Houston. And he is the lead lunar exploration scientist at JSC. His research is focused on using petrology which is the study of rocks and the conditions under which they form. I know because I looked it up. His research is focused on using petrology and remote sensing to investigate the composition, origin and evolution of planetary surfaces. He’s been heavily involved in the development and testing and the science operations of the Lunar Reconnaissance Orbiter which is now ten years into studying the Moon up close. He is also busy in Project Artemis in the formulation of science objectives and operations for the next generation of exploration on the Moon. As they say, “we are going.” And today we talk about what we hope to do and to learn when we get there. Okay then. Here we go.

[ Music ]

Host: Let me start by helping to introduce the audience to who you are. Where does your interest in the Moon come from? Does it come out of the Apollo missions from 50 years ago or some other aspect of astronomy or geology?

Samuel Lawrence: Well, that’s a very good question. Back when I started into graduate school in the 2000’s, discovery of the potential microfossils in Meteorite ALH84001 was in the news and so like many people I actually went to graduate school to do Mars work.

Host: Yeah.

Samuel Lawrence: Mars. But I’ve always been interested in lunar exploration. Starting when I was a kid growing up, we had the space shuttle, had just started to fly. That’s the reason why I’m here, and one of my earliest memories is watching Columbia launch on her first flight as STS-1. And so that’s very inspirational. It has an effect on people. And keep in mind the space shuttle wasn’t just — at the time it was first launching, it was the tool that was going to open up the space frontier to the human species and we were all going to get a chance to ride in the space shuttle.

Host: You were going to go there, back and forth all the time.

Samuel Lawrence: We were going to go, yeah. I had a pamphlet that was put into a lot of Cheerios boxes when Columbia’s first flights were going on. It was like, “You will ride to work one day on a space shuttle.” And you read that stuff and it does have an impact on you. And I think that actually did pull in a lot of young people in the early 1980’s into the science, technology, engineering and math fields. So it does have, you know — the space program does have a demonstrable impact on what young people choose to do with their careers. But again, during the 80’s it was sort of assumed that we would all be — you know, the 21st century was right around the corner. We would have moon bases and people on Mars. And the first President Bush hopped up there in 1988 and says, “We’re going to back to the Moon to stay and then on to Mars.”

Host: Right.

Samuel Lawrence: And so like most people, like most fourth-graders, when the president hops up there and says that, you might reasonably expect it’s going to happen. And it’s really kind of a shame it really didn’t turn out the way we had been told. That is truly unfortunate because it does indicate something about our ability to make and follow long-term plans as a culture and as a society. But anyway, to answer your actual question, I’d always figured I would go to college to be an aerospace engineer. But I read — you know, growing up in the 90’s, you know, there was a lot of backing and forthing. And I read some op-eds by a guy named Paul Spudis and I was like, “Wow, this makes really good sense.” And so I was very excited about aerospace. I was going to go to college to be aerospace. And then I read a book by the legendary lunar geologist Don Wilhelms who did a lot of work during Apollo. And it was very interesting and I had this very epiphany that if you’re really going to do space in the 21st century, then understanding where the resources are to enable human exploration is going to be a really important question.

Host: And you’re talking about the resources that are out there in space.

Samuel Lawrence: Out there in space, that’s right. Yes.

Host: Yeah.

Samuel Lawrence: And so I changed course slightly and became a geologist. And you know, geology’s a very interesting field. It’s very integrated. Any given day you might have to understand biology and physics and thermodynamics and chemistry in order to understand the history of rocks and how it worked on this planet. And in the book that Don Wilhelms wrote, “To a Rocky Moon,” he made the really cogent point that up until the space age, the Moon had been an object of fascination for astronomers. But the space program and the space race converted it into an object we could explore and understand using principles of terrestrial geology to understand how the Moon worked. And the great gift of Apollo was that it essentially opened up our understanding of the entire solar system and the universe around us in a way we could understand. And so when I went to college, I went — or when I went to graduate school rather to get my doctorate in planetary science, I originally did it to do Mars work. And then I met — and then I just sort of realized there was a lot of interesting stuff to be done on the Moon. And everyone else was doing Mars work, so I figured, I might as well just switch over to moon work and then I’ll have less competition.

Host: Yeah.

Samuel Lawrence: Which proved to be an interesting choice.

Host: Have you been at NASA for your whole career?

Samuel Lawrence: No. No. I was hired three — I was on the research faculty at Arizona State University and I was hired at Johnson Space Center three years ago specifically to shore up their lunar expertise in anticipation of a new program of lunar exploration.

Host: I read an article in getting ready for today that quoted you as saying the “Moon is the Rosetta Stone for the whole solar system.”

Samuel Lawrence: That’s actually true.

Host: That’s pretty high praise.

Samuel Lawrence: Yeah.

Host: Tell me why you think that? What is it that we can learn studying the Moon that teaches us about the rest of the solar system?

Samuel Lawrence: Well, that is a very good question. So in general, when we went to the Moon the first time, we didn’t really understand — there were still major questions in the 60’s about where did the Moon come from? There are these features on the lunar surface that look very much like rivers. And so there were people, serious scientists making serious suggestions there might have been liquid water on the Moon at one point. They look just like rivers. So they must be.

Host: Well if it’s the evidence of your eyes and it’s the only evidence you have.

Samuel Lawrence: That’s right. That’s right. So then we went to the Moon and we discovered, as I sort of alluded to previously, that the Moon gave us this insight into planetary processes, the way geology works in other planets. And one of the reasons — so we actually landed on one of things that looks like a river.

Host: Right.

Samuel Lawrence: And discovered it was actually a lava channel and the Moon had never had liquid water on its surface and that the Moon was not just an asteroid that had been captured in lunar orbit. But we discovered that it was very similar to a rocky planet. It had a crust, a mantel and a core and it had very likely been created by a Mars-size impactor hitting the primordial earth and then the materials thrown off by that impact aggregated in low Earth orbit and differentiated into the Moon.

Host: It’s formerly a piece of this planet.

Samuel Lawrence: Right. Which explains why the chemistries of the two bodies are so similar in some respects. They’re very different in others. But in some respects they are actually pretty similar. And so but the biggest reason why I say that Moon is the Rosetta Stone of the solar system is we landed with astronauts who did field work in key locations on the lunar surface. From that field work — they picked up samples, they did geology in the field, they selected — they carefully selected samples, well more carefully in some cases than others. But they selected samples that were tied back to specific locations on the lunar surface. And from that we brought it back here to Houston and then distributed those samples all over the world and did radiometric age dating, figured out how old the samples were. And very similarly to — you know when you cut down a tree you count the number of rings?

Host: Right.

Samuel Lawrence: And that tells you how old the tree is. Well, on another planet, especially ones that don’t have atmospheres, it’s the number of craters that tells you — they can be used to infer how old the surface is. The more craters there are, the older the surface is.

Host: The longer it’s been there exposed to passing asteroids.

Samuel Lawrence: That’s right. That’s right. And so there are always exceptions to every rule and that’s sort of a gross oversimplification of it. But in general that rule holds. The older the surface, the more craters there are. So what you could do is you could count the areas near the Apollo landing sites, see how many craters are on those areas and then figure out because we have samples, the radiometric age dates, you know, see how old they were. And then that time scale has actually been extended to every single one of the inner terrestrial planets. Mercury, Mars, Vesta. And it really is this gift that has kept on giving. You can make a pretty good case in a sense it is actually what happened that most of the discoveries we’ve made in planetary science for the past five decades are directly or indirectly related to the discoveries made by the Apollo astronauts on the surface of the Moon. That was landing in six locations for only a few days at a time.

Host: Right.

Samuel Lawrence: For over a two-year period. So imagine what’s going to happen when we go back to stay. I cannot predict it. That’s why you explore, right? But in general we do really need to go back to the Moon and get more samples and understand the radiometric age dates of other locations on the Moon. Because it sort of turned out that the Apollo — the six Apollo landing sites and the Soviet landing sites were all actually in a very narrow band along the equator of the Moon and they’re not actually truly representative of the Moon as a whole.

Host: Not distributed across, around the whole body.

Samuel Lawrence: That’s right. Yeah. So we do actually need to go back and get more samples and understand when things happened on the Moon. And that will actually help us to understand when things happened in all the other terrestrial planets too. So that’s one of the key objectives for what we’re going to do for future lunar missions as well.

Host: I must ask for everyone like me that doesn’t know precisely what radiometric dating is.

Samuel Lawrence: Well, there are certain isotopes that decay over time. If you’ve — I guess it’s — for those of us who grew up during the Cold War, it’s probably an easier story to tell than others. But basically when a rock is erupted and forms onto a planetary body, it has certain elements that degrade naturally over time, radioactive decay. You can measure the abundances. And the way the decay rates are known. They’ve been measured in laboratories. You can measure the amount of these radionuclides in a rock and figure out based on what the abundances are how old the rock is.

Host: How long it’s been deteriorating.

Samuel Lawrence: Yeah, that’s right. How long the radioelements have been decaying over time. And then do math and figure it out.

Host: See, the math part is the hard part that keeps —

Samuel Lawrence: That’s actually the easy part. It’s the measurement that’s the hard part, but sure.

Host: You’ve started to touch on some of the importance of the science of what we can learn at the Moon. We learned about the age of the planets from the Moon. How do you characterize generally — and then we’ll get more specific — about the value of the science that we can get from going to the Moon?

Samuel Lawrence: Oh, it’s immense. And the value you get from sending human explorers is going to be even larger. I think one of the key points I like to make which I sort of already have made is that we only landed on the Moon with human beings six times. And they only explored a very small, vanishingly small area of the lunar surface. And they had intense schedule pressure, intense time pressure. And you’ll always have that in spaceflight. But if you’re going back and our paradigm this time around is different. We’re not going on camping trips. We’re going to stay. And that means we’re going to — if you’ve listened — so right now at NASA our focus right now is the 2024 landing, the Artemis III mission. But beyond, yeah, what comes after that, we’re still working on it. It’s still in development.

Host: Right.

Samuel Lawrence: But the Space Council and the Vice President and the administrator have all been very clear we’re going this time to stay and that requires a paradigm shift. It’s not a camping expedition. We’re going to go back and establish some sort of permanent presence on the lunar surface. And hopefully enable sustainable exploration in a way that doesn’t — you know, Apollo was fantastic but Apollo got cancelled and we don’t want to have that happen again.

Host: And Apollo wasn’t meant to go there to stay. Those missions were meant to go there for those short periods of time and come home.

Samuel Lawrence: That’s right.

Host: It’s not like it was their fault. But now we’re doing something different.

Samuel Lawrence: That’s right.

Host: We’re going there to stay there to learn more about the place and to learn how we can stay there for a long time.

Samuel Lawrence: That’s right.

Host: Long periods of time.

Samuel Lawrence: That’s right.

Host: Are there certain aspects that you think of lunar science, if that’s the right phrase to use, that are more valuable? What are the more valuable areas of science that we can learn about?

Samuel Lawrence: Well, I think there’s a lot. Obviously there’s — in terms of understanding fundamental processes in the solar system, you know, the impact process. It affects every single planet in the solar system, not just the Moon. It affects Earth. That’s why we’re having this conversation, not, you know, some dinosaur radio show or something, right? I mean, that’s why we’re here.

Host: Right.

Samuel Lawrence: So the impact process is fundamental. Understanding what exposure to the space environment does to a surface. Understanding the physics of how light interacts with the surface to understand how do you use remote sensing techniques to interpret mineralogy and composition. All of these are fundamental processes across the solar system, and the Moon is a natural laboratory for them. The Moon also records the first billion years of the history of the Earth/Moon system. So on earth we have plate tectonics and that tends to recycle, you know, the continents. You know, materials from the earliest part of earth when one-celled organisms were starting to crawl out from under the ground and get onto the surface and start the long evolutionary path that resulted in us — that’s all gone. We don’t have that record on this planet anymore.

Host: Because it shuffled up the evidence.

Samuel Lawrence: Yes. Well, evidence was destroyed by plate tectonics.

Host: Right.

Samuel Lawrence: But that evidence is there on the Moon. The Moon actually does record because it’s the Earth/Moon system. It does — the first billion years is available and can be found on the Moon. It’s not saying you can say, “Well, we’re going to go to this spot and find it.” But with a long-term presence on the lunar surface and lots of astronaut field work, you will find it eventually.

Host: Because there aren’t plates and tectonics on the Moon.

Samuel Lawrence: That’s right. There’s no plates. There’s no tectonics. There’s no recycling. You know, you will find it on the Moon and that’s very interesting. That will tell us a lot about the rise — you know, we’re always talking about how to find life in the solar system, but how life evolved on Earth is a very, very important question for us. And a key part of that story is told on the Moon and only accessible there.

Host: It’s not just the lack of plate tectonics. The Moon doesn’t have weather or other things.

Samuel Lawrence: That’s right.

Host: Or other things that would disturb the evidence of these ancient events.

Samuel Lawrence: That’s right, yeah.

Host: Does the Moon have natural resources?

Samuel Lawrence: Well, that’s one of the great discoveries we made during Apollo. So even before — even before we started to understand the nature of the polar volatile deposits that everyone is talking about today, even during the Apollo missions we began to have an understanding that the Moon actually did have a lot of resources that could enable future human exploration. Jack Schmidt, the only geologist who ever flew to the Moon, sampled a thing called a pyroclastic deposit at the Apollo 17 site. And it turns out those are spread across the near side of the Moon. They have a uniform chemical composition. We can use simple chemistry to extract water and oxygen from these materials. They’re large. And so this field — we had, you know, lunar base concepts in the 80’s that would have worked that used these deposits as the feedstock to sustain astronauts on the lunar surface. So you know, we’ve been thinking about this problem for a long time. And then in 1994, the Clementine mission was flown and that discovered the first tantalizing hints of potential water deposits or potential volatile deposits I should say at the lunar poles.

Host: You want to make the distinction between water deposits and volatile deposits?

Samuel Lawrence: Well, there’s a perception out there that there are these skating rinks hidden in the lunar poles. And unfortunately or that is not in fact the case. Our lunar reconnaissance orbiter mission has shown that there is no observable skating rinks at the lunar poles.

Host: No big slabs of ice.

Samuel Lawrence: No big slabs of ice. But it has detected pretty conclusively — and there was a mission called LCROSS, the Lunar Crater Remote Observation Sensing Satellite.

Host: Good for you.

Samuel Lawrence: It was co-manifested on the LRO launch in 2009 that impacted into Cabeus Crater on the Moon and discovered the unambiguous presence of water, H2O. And a lot of other possibly economically useful materials as well like methane. And the reason this works — we sort of skipped a step there — is that the Moon has a slightly tilted orbit. And so there are areas at the lunar poles where the sun both never stops shining or effectively, you know, where you have a lot of illumination, and where the sun never shines.

Host: And when you say tilted, you’re saying — is that in reference to —

Samuel Lawrence: To the sun.

Host: To the sun.

Samuel Lawrence: That’s right.

Host: And the side of the Moon that we see is the same side all the time.

Samuel Lawrence: That’s right. Because the Moon is tidally locked. And there is no dark side of the Moon. This isn’t an Isaac Asimov novel. There’s a far side of the Moon which we never get to see, but it does get the same day/night cycle that the rest of the Moon does. But at the lunar poles, and this is why this is the target for the Artemis program, there are these areas of near-permanent illumination. And that has a couple of very positive effects. It means that the lunar night only lasts for something like 6-7 days at a stretch as opposed to 14 days. And you get 200-day periods each year where the sun never stops shining. And so it’s a great spot to put down a stake hold and try to figure out how to live and work on other planets.

Host: Because you would have 200 days of sunlight to provide power?

Samuel Lawrence: That’s right. And it’s also a benign thermal environment. So on the moon there’s this diurnal day/night cycle with an extreme of temperatures. And at the poles the swing is much less. It makes it easier to design habitats. It makes it easier to design systems to enable astronaut habitation on the surface.

Host: The change is less but still what’s the temperature we’re talking about? It’s not an Earth kind of temperature.

Samuel Lawrence: It’s equivalent to what you’d see on the International Space Station. So you’re looking at around 200 degrees Fahrenheit in the daytime.

Host: Okay. So it’s an environment that we already kind of know how to live in?

Samuel Lawrence: That’s right.

Host: We’re talking about natural resources. Are these natural resources — it sounds like they would be useful to us in order to be able to go there and stay, as opposed to resources that are valuable that people would want to go and take away and sell somewhere.

Samuel Lawrence: It’s very difficult to make the case that anything you mine in space is ever going to come back to Earth, for now. That could change in the future, but for right now the most near-term utility for lunar resources or any space resources — and asteroids are chock full of useful things too, useful for people in space. So the things we’re interested in are oxygen. Oxygen is rocket propellant, the stuff you breathe. We’re interested in the possible, you know, volatiles which is hydroxyl, because that can be easily split off into oxygen and hydrogen which is rocket fuel. So there are — you know, the near-term things —

Host: And the oxygen is water? Or the other way around?

Samuel Lawrence: Yeah.

Host: Yeah.

Samuel Lawrence: Yes.

Host: Yeah.

Samuel Lawrence: The water can easily be converted into oxygen and hydrogen.

Host: Right.

Samuel Lawrence: So you know, we care about these things because oxygen is not only the stuff you breathe but it’s oxidizer for rocket fuel. The hydrogen could also be rocket fuel. And so, like I said, the near-term thing is going to be focusing on enabling and making human exploration more sustainable. And the reason why is that it takes roughly six times — there’s a six-to-one gear ratio for getting stuff to the Moon, is sort of the lingo. And that’s because for every pound you have to take to the lunar surface it takes roughly six pounds of fuel to get it there.

Host: Okay.

Samuel Lawrence: So give or take. So anything you can make on the lunar surface will eventually pay for itself, no matter how — you know, and you always hear people talk about, “Oh, you know, launch prices will go down eventually.” Sure. Maybe. But it still doesn’t change the fact you’re still going to take six times as much fuel to get something to the lunar surface. So the more you can make on the Moon, the easier it will be to sustain a human presence there.

Host: The less you have to take.

Samuel Lawrence: The less you have to take.

Host: And the less of your resources here on Earth you have to expend for that portion of it.

Samuel Lawrence: That’s right. And also you have to learn how to live off the land if you’re ever going to do Mars sustainably too. Because you’re much, much farther away than, you know — going to Mars is a much bigger technological leap and to really do it right, again, if you’re going to do it in a way that doesn’t eventually get cancelled, you want to have a sustainable presence on the Martian surface. You have to learn how to live off the land and use local resources. So it’s an important paradigm shift and we can get started doing it on the Moon.

Host: You made reference to the lunar South Pole as a place where water, ice, has been found. Are there other of these valuable materials also in that same general region, making it a nice target for us to want to go to first?

Samuel Lawrence: I mean, what do you mean valuable materials?

Host: Well, the other natural resources.

Samuel Lawrence: Oh, other natural resources. Well, you can take lunar regolith and craft oxygen out of it pretty much anywhere on the Moon.

Host: And regolith is?

Samuel Lawrence: Lunar soil.

Host: Okay.

Samuel Lawrence: Yeah.

Host: And you can get oxygen out of the dirt?

Samuel Lawrence: Yeah. It’s chemistry. You can do it. So you can — some of the higher-grade resources are only found in equatorial regions of the Moon. So we’ll have to — like I said, this is a marathon, not a sprint. So we want to try to establish a beach head at the lunar South Pole and then eventually branch out to doing other missions to other places with gradually increasing capability. And that is why the Moon is very interesting, because it’s not just an interesting scientific target. It’s an interesting aspiration target. And we are not — we don’t just want to go to Moon and stay there. Going to the Moon actually gives you the capabilities you need to go anywhere you want in the solar system with any capability you might actually have.

Host: The things we can learn by going to the Moon and staying teach us.

Samuel Lawrence: And the workforce and technologies required to go back to the Moon will reenergize the aerospace industrial base and give us a body of knowledge which you know, I mean, has been lost or is on the verge of being lost. The Apollo generation is leaving us. No one alive, or very few people present at the agency today have designed a vehicle that’s landed human beings on another world.

Host: Right.

Samuel Lawrence: And so we actually need to relearn how to do stuff we once learned how to do.

Host: We’ve been talking for a few minutes about what there is on the Moon and it occurs to me to make sure I understand how we know that. I mean, we didn’t — it’s been 50 — almost 50 years since the last human beings went there and gathered up samples for us to bring back. But is that the primary way that we know about what’s on the Moon? Or have we learned it from other things? And I’m thinking particularly of the Lunar Reconnaissance Orbiter that you also worked on.

Samuel Lawrence: Right. Well, over the past two decades we’ve had a nice renaissance in lunar exploration. Because it’s not — yeah, like I said, the Moon is a very accessible target and so it’s something we can actually get to relatively straightforwardly. And so we’ve had certain — the Clementine mission which gave us our first global mineralogical maps of the Moon and the first tantalizing hints of polar volatile deposits. We’ve also had a series of international missions. So we’ve had our colleagues in India launch the Chandrayaan mission, Chandrayaan I. And you have Chandrayaan II on its way to the Moon right now. We have had the European Space Agency launch SMART I. Our colleagues in Japan launched the KAGUYA mission. And KAGUYA was a fantastic mission. It produced a tremendously valuable global dataset for mineralogy and composition and topography. Then we also finally had the Lunar Reconnaissance Orbiter which was launched in 2009 as the first step of the — first actual mission launched as part of the vision for space exploration, President Bush’s former program to return to the Moon and stay and go on to Mars. And so LRO really I think is an example of how you know — how science can enable human exploration. The mission was an exploration mission, an ESMD, Exploration Systems Mission Directorate mission, but it was staffed by Science Mission Directorate scientists and it was expressly designed to collect the data needed to enable a program of lunar exploration. But along the way, it also produced fantastic paradigm-shifting science and reinforced the Moon’s status as the cornerstone of planetary science. So it made a series of very important discoveries. Among them abundance of volatile deposits at the lunar polar regions, but also new details of lunar mineralogy, lunar chemistry, the lunar landforms we can see with LRO’s camera system, land forms as small as a meter in diameter.

Host: Wow.

Samuel Lawrence: So we’ve discovered all kinds of interesting things about lunar geology and the physics of the impact process, and created a whole new set of places we really want to send astronauts and their robotic precursors. So ten years into the mission, we have fuel for six or seven more years of operations. It’s my finest hope that we can actually have LRO still in orbit and taking images when the next American steps onto the surface are taken. That would be a nice shot.

Host: Overhead shot.

Samuel Lawrence: Yeah, that would be a nice symbolic closure of the mission.

Host: It would. I’ve wanted to set the stage for what there is there on the Moon to talk about what we would find when we go back. And part of your current portfolio is that you’re working on developing the scientific objectives and the ways to do research during the Artemis missions that are coming up. It’s still early in Artemis.

Samuel Lawrence: Still early.

Host: To the extent that you can, what’s the outline of flights as we understand it so far?

Samuel Lawrence: Sure.

Host: What’s the early plan?

Samuel Lawrence: Well, we had an exciting conference in January of 2018 called the Lunar Science for Landed Missions Workshop that went through and it was a great meeting and it went through — it was sponsored by our friends at the Solar System Exploration Research Virtual Institute. And it was at the Ames Research Center. And that was a great meeting. It was the science community coming together and going, “These are our high-priority targets for where we’d like to send precursor missions and also” — it was mainly focused on precursor missions, but all the stuff from that workshop is equally applicable to the human missions. So an inherent part of the Artemis concept is that we have this thing called the Lunar Discovery and Exploration Program. So part of that is going to be — it’s an exciting program. It’s leveraging the power of American enterprise and American industry to create a whole new set of lunar landing vehicles and designs to carry payloads to the lunar surface. And as part of that program, or actually as part of LDEP we’re going to be landing exciting new missions for science at various spots around the lunar surface. I don’t know where they’re going to be landing, but they’ve selected instruments and they’ve selected payloads and there’s several contractors working right now to create new American lunar landing systems that will take US payloads to the lunar surface. So that’s really exciting, and that’s a key capability. Because as I mentioned previously it’s been five decades since the United States landed a spacecraft on the lunar surface. So I view LDEP as a really important part of our lunar portfolio and I’m really looking forward to the discoveries those missions are going to make.

Host: And if I can, to be clear, the LDEP payloads are not humans down to the Moon.

Samuel Lawrence: That’s right.

Host: These are research missions.

Samuel Lawrence: That’s right. But for this to work and work sustainably, we’re going to have to have robots and humans working together. And I think that really does act as a force multiplier and it’s going to make our exploration more effective and efficient and affordable when we can have regular cadence of missions going to the lunar surface. Because I could see scenarios where you are flying payloads designed to understand how to produce resources on the lunar surface to the moon on these LDEP payloads.

Host: If we’re going to make use of those resources, we’ve got to have the tools to do it.

Samuel Lawrence: You’ve got to have the tools to do it. So I think it’s a very good synergy between the mission directorates. It’s a very exciting program. It’s very innovative. It’s going to be I think really exciting to see what American commerce can bring to the game in a way that is designed to enable innovation. And then moving on beyond LDEP which is our first missions as part of so-called Artemis umbrella are going to be LDEP missions.

Host: Okay.

Samuel Lawrence: In the early 2020’s. And then we have the Artemis III and that’s the first human mission as part of the Artemis program, presumably the seventh human lunar landing. And we have clear direction from above to land at the lunar South Pole which is a very interesting location. Like I said, there are — it’s an interesting environment that is enabling for future human exploration for long durations on the lunar surface. There’s potential access to these volatile deposits which are not only interesting as a potential resource but are also interesting scientifically because it’s that — like I said, the first billion years of history. So we can go to these volatile deposits and presumably understand how organics and other cometary materials evolved over time in the solar system. That’s an interesting thing scientifically. And there’s also rocks we can pick up, and potential multiple — potentially sampling multiple lunar terrains with access to the — or excuse me, which could be accessed by landing at the South Pole. And by astronauts doing field work. So it’s an interesting location. We’re still working on some of the details here, but in general the idea is astronauts will land there and get out of the spacecraft, do space walks and make some very interesting new discoveries as they start to figure out what it’s going to take to learn how to live and work on other planets.

Host: So if that’s Artemis III, Artemis I and II and LDEP missions?

Samuel Lawrence: No, no.

Host: No? Okay.

Samuel Lawrence: Those are the missions formerly referred to as Exploration Mission I and Exploration Mission II on the space launch system.

Host: I see.

Samuel Lawrence: So those are Orion test flights in lunar space.

Host: Okay. And Artemis III gets the first humans back to the Moon?

Samuel Lawrence: That’s right.

Host: And you made reference there, if I can — there’s a little exit ramp there. You were talking about doing exploration and finding evidence of the evolution of comets?

Samuel Lawrence: Well, sort of.

Host: Okay.

Samuel Lawrence: That was perhaps inelegantly phrased by me. What I’m alluding to here is again the Moon preserves its first billion years of history of the Earth/Moon system. And the reason why you have these polar volatile deposits is that again the Moon has these areas where the sun never shines. And when comets which are sort of wet, muddy ice balls hit the Moon, those volatiles during the lunar day/night cycle literally hop from one spot to another on the lunar surface. And eventually they get trapped in these cold traps at the poles. That process has presumably been going on for most of the history of the solar system. So by going to these volatile deposits in the lunar Polar Regions and studying them — and we will get some of this data as we use these resource deposits for resources as we do resource extraction. As you start to really dig down into these deposits, you will get interesting information about how these volatile rich compounds, you know, water, methane, have involved over the complete four-billion-year history of the solar system.

Host: Because you will have had evidence of them from throughout that timeline.

Samuel Lawrence: That’s right. That’s right. And we just went to the Moon and found it. And so it’s going to be very interesting to see what develops out of this.

Host: How do they hop from one place to another on the Moon?

Samuel Lawrence: Boiling. So the water boils and then it gets so far — some of it gets lost to the space environment, obviously.

Host: Okay.

Samuel Lawrence: Some of it lands when the sun goes down, and then the sun rises and the process repeats. And then eventually, so you know, from the giant ice ball that hit the Moon at the equator, a few molecules wind up in the lunar poles.

Host: It’s dispersed.

Samuel Lawrence: Yeah. But they get trapped in the polar environment. That’s a gross oversimplification. I’m sure some of my colleagues are cringing at the thought of it.

Host: Well, but you can imagine why when I heard it hops from one place to another that you had more clarification than that.

Samuel Lawrence: Indeed.

Host: So you talked about up to Artemis III and the first humans that would land by 2024. Are there plans for further human missions in that timeline beyond that?

Samuel Lawrence: Sure. I mean, the idea is —

Host: Do we know much yet?

Samuel Lawrence: A lot of this is still under development. But you’ve seen in some of the public talks given recently at the NASA advisory council and other places, there is essentially — there are plans for other missions beyond 2024. So usually —

Host: Since we’re going to stay.

Samuel Lawrence: Since we’re going to stay, yes. So you’ve seen charts shown that show, you know, one mission a year in ’25, ’26, ’27, ’28 and continuing thereafter. So it should be interesting.

Host: Yeah.

Samuel Lawrence: As we establish this capability to do human planetary exploration.

Host: What would you say are both the immediate and the long-term goals of Artemis at the moment?

Samuel Lawrence: Well the long-term — the immediate goal is to reestablish a credible capability to get human beings onto another planet. And you know, this, like I said, it’s something we haven’t done in a while. And if you’re really going to be credible about saying, “Yes, we can go to Mars or go to Sirius,” or go to other places we want to go to, it makes sense to establish that capability in a place that’s really only a few days away. Where you can take risks and have some confidence you might be able to get back to earth in a reasonable timeframe to preserve human life. The other — there are other near-term objectives too. I mean, one of them besides reestablishing planetary exploration with human beings is understanding the lunar resource potential and understanding how to use it. Understanding how to incorporate that into human space flight architectures I think is a really key paradigm shift.

Host: Knowing more about what’s actually there on the ground.

Samuel Lawrence: Knowing — well, both. More about know what’s actually there in the ground and providing ground trips, but also figuring out how to design systems that can leverage it once you find it there. Because again, you have to do that for just about anywhere else you want to go in the solar system.

Host: Sure.

Samuel Lawrence: So it’s a key paradigm shift. And understanding how to, you know, refuel a spacecraft in microgravity or fractional gravity environments is a thing we’ve never — don’t have a lot of experience with. So we need to get some of that. Understanding and developing systems that can handle not just days on the lunar surface but months or even years of surface operations is critical for understanding, for enabling again longer journeys to Mars and beyond. So I think there’s this whole host of technology development things that should and will come out of the Artemis program. There’s scientific discoveries about the nature of the early Earth/Moon system, of fundamental planetary science processes. There’s also things you can do on the Moon that aren’t related to geology. There’s interesting — there’s interesting things you can do from materials science. There’s interesting scientific objectives for understanding the biological impacts of fractional gravity on human beings. Again, we have lots of data from ISS. We have lots of data at 1G on this planet.

Host: Yeah.

Samuel Lawrence: Very little between those two extremes. So having astronauts on the lunar surface for months or even years at a time or for weeks or months, possibly even years at a time will provide a critical data point for understanding what fractional gravity — what the effects of fractional gravity are in human beings and possibly also developing coherent mitigation strategies for them. It is possible there is some number between zero and one where the deleterious effects of microgravity exposure are mitigated to some large degree. And that could be very useful for future exploration.

Host: I think it’s very important that you point that out. Because a lot of times we, I think, maybe overlook the fact that the microgravity environment that we’re learning about on the space station is not what you have on the Moon.

Samuel Lawrence: No. It’s not what you have on Mars either. Yeah.

Host: There is gravity there. Not as much as Earth, but there is gravity.

Samuel Lawrence: There is gravity. And it turns out, you know, there are areas on the Moon, like I said, the far side is shielded. It never sees the near side. So there are interesting things you can do from radio astronomy, looking for the early cosmic dawn. There’s teams of astronomers who are really excited about putting a radio telescope on the lunar far side. Again, with a field station on the lunar surface, permanent power production infrastructure, these kind of long-duration experiments become very possible. And the Moon I think will eventually become a platform very much like the ISS where you can use it for a variety of interesting things. And that’s really exciting. You know, I can’t — it’s difficult to predict the future. You know, always in motion, the future is. But once you establish the capability to access the Moon’s surface on a regular basis, have infrastructure there to support long-duration experiments and activities, very exciting things are going to start happening. It’s going to be very interesting to see.

Host: Set up on the far side of the Moon and able to look out in a way that we can’t do from earth.

Samuel Lawrence: That’s right. Because it shields all the radio transmissions, right?

Host: Those coming from Earth?

Samuel Lawrence: Those coming from Earth. Earth is very noisy, but the far side of the moon is very quiet so you can actually do interesting radio astronomy from the lunar far side that is unique for the solar system.

Host: Talk a little bit about what kind of work we’re doing now and work we need to be doing in the near-term future in order to support these goals of Artemis on the Moon.

Samuel Lawrence: Yeah, it’s very interesting. So some of this work, you know, we’ve restarted it. It was quiescent for some time. So some of that work is slowly coming back to life as we realize we have to do this again. We’re looking at where do you actually land? Where are the spots on the lunar surface that are safe that can be accessed by astronauts and robotic precursor missions? How do you account for, is there enough space to put landers down close together without having dust impingement on each other? So there’s a lot of applied science research going on right now as we try to answer these questions in a way that makes sense and enables value to the taxpayer. We’re working on the new space suits that will enable lunar missions. We’re working on developing mobility systems that will let astronauts — you know, like rovers that will let them go.

Host: Yeah.

Samuel Lawrence: From their lander and go out to do exploration, working on ISRU systems, in-situ resource utilization designed to use lunar resources and produce things of value to human explorers. We have American companies working on commercial landers right now to enable the goals of the Lunar Discovery and Exploration Program. So there’s a lot of work which has all of the sudden come into very clear focus thanks to the challenge of the 2024 deadline.

Host: You’ve mentioned just then and earlier too about international and private or commercial participation in all of this. This is not just a NASA by itself effort, is it?

Samuel Lawrence: No. No, it’s not. We have — there’s been for the last decade significant international interest in lunar exploration. And I think to paraphrase John Kennedy, you know, it’s as true now as it was when he said it back in 1962 at Rice University. Whatever human beings undertake, free humans must fully share. There is a lot of international interest in the Moon. And I think, you know, it is incumbent upon the United States to lead the way back. And so I think there’s a lot of — I think there’s going to be a lot of opportunities, good opportunities for our international partners to make meaningful contributions to the success of the program. All that is being worked on right now, so I would imagine there’s a lot of excitement out there in the domestic United States community about a renewed emphasis on lunar exploration. And there’s a lot of excitement from international partners about the United States finally committing to go back to the lunar surface.

Host: Well, the European Space Agency is already participating in the Orion Spacecraft.

Samuel Lawrence: That’s right.

Host: But other national space agencies are I guess — are they being encouraged to participate?

Samuel Lawrence: Yes, they’re being strongly encouraged to participate and I think that would be most welcome.

Host: And you talked about in the LDEP missions, private companies are already working on some of these — I don’t know what the right way to put it is — but science experiments that will be going and landing on the Moon on their own.

Samuel Lawrence: That’s right, yes.

Host: As well as, you know, work has begun somewhere I’m sure on figuring out the actual mechanism of putting the human beings down on the Moon too.

Samuel Lawrence: Yeah, that’s right. While that process — there’s already — there was already a set of — there was an action taken earlier this year. We call it on the inside appendix E which were essentially study contracts given to industry to study human lunar landing systems. And that’s in progress right now.

Host: Before we get too far away from the mention of it, we were talking a minute ago about dust, moon dust. And one of the things that I learned a lot about during all the recent attention to the 50th anniversary of the first Moon landing was how much of a real problem the dust was in how it messes up our stuff that we bring there.

Samuel Lawrence: Yeah. That’s actually true. But this is not — so the dust is a problem. But keep in mind-

Host: I’m not saying that it can’t be defeated, but it is one of the really — one of the big things that people have to —

Samuel Lawrence: Yeah it is. It’s something you’re going to have to do anyway, no matter where you go in the solar system.

Host: Right.

Samuel Lawrence: It turns out you find dust. So it’s something we’re going to have to address. And also keep in mind that most of the Apollo systems were designed in the early 1960’s before we had any sense of what the lunar surface was like. So yes, they had a lot of problems during the Apollo missions. Some of that was caused by the fact they took good guesses, guesses that pretty much actually worked.

Host: Yeah.

Samuel Lawrence: We’d go to the Moon, we landed safely, we returned safely. We brought back 800 pounds of lunar rocks. But you know, most of those systems were designed well in advance of any realistic or actual knowledge of what the lunar surface was going to be like. So now that we have that knowledge, now that we fully understand the characteristics of the lunar environment, I’m actually pretty confident we can come up with engineering-based solutions to most of the dust issues that people are presently worried about. So I mean, it is something you have to worry about. It is something you pay attention to. But at the same time, we actually do know what the lunar environment is like and that will make I think all the difference in the world this time.

Host: Yeah. You’re starting further ahead.

Samuel Lawrence: We’re not starting from zero, yeah.

Host: As we did before.

Samuel Lawrence: Yeah.

Host: You’ve mentioned that a big part of the goal of the Artemis program is to return human beings to the Moon to stay, to create a sustainable presence. And we’ve talked about how we want to use the resources that we will find there in order to support this sustainable presence. Is a sustainable presence on the moon the same kind of thing — or is it the same thing as a sustainable presence on Mars, which is the long, long-term goal of this?

Samuel Lawrence: Well, I would contend that the knowledge you get from going back to the Moon to establish a sustainable presence there will actually make a Mars mission happen a lot sooner. Because you have that workforce and industrial base recapitalized, I think it actually makes Mars missions more feasible, not less. It’ll happen more quickly, not farther away. But that’s common sense, right? Once you’ve done it on the Moon, it should be a lot easier to get the confidence back to go back to thinking about how to do Mars.

Host: You learn at least the general outlines of what you have to do. But there are going to be differences between the environments.

Samuel Lawrence: There will be key differences. Yeah, there are. But I would — they are actually probably going to be pretty similar. I mean, if you look at the body of work that’s been done recently for the — there’s been a lot of series of conferences and people have thought about this a lot. There’s this concept of the Mars field station. And if you look at what that is, it’s shockingly similar to what you might actually envision for a lunar field station too. So I guarantee you that establishing a sustainable presence on the lunar surface will buy down a significant amount of risk and develop a significant amount of industrial experience in how to create and fabricate habitats and have them be successful for the Martian experience. You know, there is a big difference — it will shock you I’m sure to learn — from going from a PowerPoint slide to actual hardware. [Laughter] And that is a gap we need to figure out how to jump to before we can start to really credibly talk about going to Mars with human beings. And you will do that on the Moon in a place where you can make mistakes and it’s less bad.

Host: Yeah. It’s exciting to be looking at really doing something like this, doing something that we did 50 years ago, but on steroids, in a different way. No?

Samuel Lawrence: It’s different.

Host: Okay.

Samuel Lawrence: Again, 50 years ago we did camping trips.

Host: Right.

Samuel Lawrence: We have never established a permanent or semi-permanent, whatever you choose to call it — I mean, humans won’t be there the whole time. They’ll be there some of the time. But we’ve never put down permanent human-tended infrastructure on another planet before, another world I should say. The Moon is not a planet. It’s a world. But we’ve never done that before. It’s new, it’s exciting, it’s a capability we have never had before, and I think people say, “Oh, the Moon, we’ve been there, we’ve done that.” No, we really haven’t. We went there five decades ago. We landed in six spots and we only stayed there for a few days. When we go back, this time sustainably, this time to stay, that is something we have never done before. And it will accrue incredible value for the United States, for our allies and it will send a powerful message to the rest of the world of what we can do when we can put our minds to it. Because you see the moon with your naked eye. You can see it every day. No matter how dark the sky is, no matter how much pollution there is, no matter how much light pollution there is, you can still see the moon. And when you have Americans living and working on the surface of the Moon that sends a powerful message to the rest of the world about what we can accomplish.

Host: And that’s exciting.

Samuel Lawrence: Yes, it is.

Host: I think that’s exciting. This is not the first time that the United States has said we’re going to return to the Moon and build on what we’ve learned from Apollo. What needs to happen so that Artemis can succeed where those previous efforts didn’t?

Samuel Lawrence: Well, I think — this is just me speaking personally. I’m not going to speak for the agency in this case. This is my perspective.

Host: What do you think is required for this effort to work?

Samuel Lawrence: I think we have to be very good stewards of US taxpayer dollars, more than anything else. They trust us. It is a special obligation and a special privilege to work for the American people. And I think when you go to them and say, “We need your support to do something really exciting and provide value,” it is incumbent upon us to make it work. It’s up to us. So we have to say, here’s the value proposition. These are all of the different ways. These are all of the different industries here in the United States we’re going to be creating as part of this effort. Here’s all the different ways we’re going to enhance science, technology, engineering, medicine in this country. And here is the value proposition. It’s up to us to sell it. You know, we have to be good stewards with taxpayer dollars, but in return we have to deliver. It’s up to us. So that’s my answer to that question. It is up to us. We have to deliver. We have to provide value. We have to do it in a way that is different and actually works this time. It is not sufficient to say we’re going to do something and not do it. If we say we’re going to do it, we have to do it. We have to deliver.

Host: Dr. Samuel Lawrence, thank you very much.

Samuel Lawrence: Yeah, you’re very welcome.

[ Music ]

Host: If you listened to the first part of our “Heroes Behind the Heroes” series about recovering recordings of the Apollo 11 mission control team — by the way its Episode 88 posted on April 19th — it’s still there online if you didn’t. Well, you know I tried to set the scene with some historical precedent for the attraction of exploring the Moon. And now I wish I had talked to Sam Lawrence too so I could have mixed in some delicious scientific reasons why bringing the Moon into our orbit in a symbolic sense was such a draw for folks back in the 1960’s and for many still is today. To get more into the details of what’s on the drawing boards for the Artemis program right now, go to, or check out and follow the links to Moon to Mars, and to humans in space. I’ll remind you that you can go online to keep up with all things NASA at Also, it would be a good idea for you to follow us on Facebook, Twitter and Instagram. You will thank me. When you go to those sites, use the hashtag #AskNASA to submit a question or suggest a topic for us. Make sure to make a note that it’s for Houston, We Have a Podcast. You can find the full catalog of all of our episodes by going to and scrolling for our name. You’ll also find other exciting NASA podcasts right there at the same spot where you can find us. Very convenient. This episode was recorded on August 28th, 2019. Thanks to Alex Perryman, Gary Jordan, Norah Moran and Belinda Pulido for their help with the production. To Noah Michaelson for his help in arranging the guests, and to Sam Lawrence for sharing his knowledge and insights about the object of our affection. We’ll be back next week.