From Earth orbit to the Moon and Mars, explore the world of human spaceflight with NASA each week on the official podcast of the Johnson Space Center in Houston, Texas. Listen to in-depth conversations with the astronauts, scientists and engineers who make it possible.

On Episode 236, David Kring and Julie Stopar detail interesting lunar research and how they’re preparing for continued lunar surface exploration through the Artemis program. This episode was recorded on March 4th, 2022.

Transcript

Gary Jordan (Host): Houston, we have a podcast! Welcome to the official podcast of the NASA Johnson Space Center, Episode 236, “Moon Geology.” I’m Gary Jordan and I’ll be your host today. On this podcast, we bring in the experts, scientists, engineers, and astronauts, all to let you know what’s going on in the world of human spaceflight and more. We’ve talked a lot about Artemis missions and the technology and infrastructure to actually make these missions possible. And the Artemis missions are to, of course, return humans to the Moon in a sustainable way. There’s a lot of reasons why we want to continue human presence on the Moon, and one of the biggest is science. And a lot of researchers are excited for what’s to come and are already contributing to the mission. Right here in Houston, very close to NASA’s Johnson Space Center, is the Lunar and Planetary Institute, or LPI. LPI is a scientific research facility studying the solar system, and they contribute some of this research to NASA, as we learn more about our Earth, Moon, Mars, and beyond. On this episode we’re bringing in LPI Principal Scientist Dr. David Kring and LPI Staff Scientist Dr. Julie Stopar. They describe their lunar research and why they’re excited to return humans to the Moon as part of the Artemis program. Let’s get into it. Enjoy!

[Music]

Host: Julie and David, thank you so much for coming on Houston We Have a Podcast today.

Julie Stopar: Thanks, very happy to be here today.

David Kring: Delighted to talk about Artemis today.

Host: Oh, it’s going to be a very exciting topic. I can’t wait to get into the science. You guys have been doing a lot of work around the Moon and, and in support of the Artemis program, so, so that’s what I wanted to dive into today. But I wanted to first start with just understanding a little bit about what it took for you guys to, to be where you are today at LPI working on the things that you’re working on. Your, your backgrounds are, are quite extensive. So, so David, we’ll, we’ll start with you first: just how you ended up having an interest in geology and, and what led you to do some of the research that you’re doing, go on the fantastic excursions that you’re going on, and then ultimately, start working on the Artemis program.

David Kring: Well, I have to say, I, I’m old enough to actually remember Apollo. And so as a young child I saw Neil Armstrong and Buzz Aldrin walk on the lunar surface, as well as their colleagues in subsequent missions, and that inspired me to go into science. And I have to say that planetary science as a field did not exist at that time, and so when I went through school I had to study geology and astrophysics hoping that the two types of science would help me better understand the Moon. I had an opportunity as an undergraduate student to be an intern at the NASA Johnson Space Center, studying the Apollo samples, and in fact I had an undergraduate thesis analyzing Apollo soil samples. I then had an opportunity to do a Ph.D. at Harvard University, then had a professional post teaching at the University of Arizona before I was pulled back to Houston to help with the Constellation program’s effort to land astronauts on the lunar surface. And so I am still here and anxious to apply those talents to the NASA team and, and help our Artemis astronauts on the lunar surface.

Host: Very awesome. Can’t wait to dive into some, some of the ways that you are doing exactly that, David, but first let’s go over to Julie. Julie, you’ve also, you also have a lot of awesome research that you’re doing in support of NASA. Can you tell us a little bit about your interest in geology and what got you to where you are today?

Julie Stopar: Yeah, yeah. I began my professional career as a geologist, for sure. My first job was actually as a hydrologist, so I was doing things like testing well water for contaminants and measuring stream flow. And then after that I, I decided I wanted to go to grad[uate] school for a while and it was really great because that was really the part where I was able to really get involved in planetary science. As an undergraduate I hadn’t really considered planetary science as a field or a career, and it really wasn’t even until, you know, my final year of study as an undergrad that I had the opportunity to take a class that introduced me to a lot of the planets and the moons and the solar system in general. So, you know, it wasn’t really a thing that I had considered much until that point. Yeah, but it, it’s kind of funny because like, I didn’t really have the Apollo experience and the textbooks that I did have, well, most of them were pretty like low-quality reproductions of Apollo images, so it didn’t really look as amazing as I know it is now. [Laughter] But yeah, it was just like lots of low-resolution, low-quality reproductions, things, but it did really open my mind to this idea of studying geology and other planets. And so after I took a few years off to get some work experience, then I, I made the decision to go to grad school for planetary geology. Yeah, and, and after that pretty much, you know, it just, I kept getting amazing opportunities to work on different things. I, I did a masters at the University of Hawaii and got an opportunity to join the Lunar Reconnaissance Orbiter camera operations team, and that was such an amazing opportunity and experience. And that was really the moment that inspired me to study the Moon and lunar science. It was just like the whole, whole world opened up, because I had the opportunity to see these amazing new images and really actually see the Moon as this wonderful place.

Host: It was the imagery then that sold you; it was, you know, from, I guess from if looking at the Moon, it just looks like a ball, but as you get closer you realize, is it, is it, like you realize all the wonderful features about the Moon as you get that better imagery?

Julie Stopar: Yeah, yeah, so it’s definitely the images. Yeah, like just it’s sort of became like this real world to me, like not just like, like a thumbnail in a book somewhere but like, it actually felt like a real world, just like the Earth feels like a real world.

Host: Yeah. And you, and you both have been, have a lot of research into the Moon as this very dynamic, very interesting place. And that’s what I want to talk about today is, all, all of the different ways that you guys have, have been fascinated and sold by just how interesting the Moon is and all the great science that, that that’s there. So let’s dive into a little bit of your research. Julie, let’s continue with you because you mentioned the Lunar Reconnaissance Orbiter. Can you tell us a little bit about what that is, and, and what kinds of things you’re doing with the Lunar Reconnaissance Orbiter to support Moon geologies and science?

Julie Stopar: Yeah, yeah. The Lunar Reconnaissance Orbiter, or LRO, which is much shorter acronym, is still orbiting the Moon right now. It launched in June of 2009, so we’ve been there, I guess it’s about 13 years now, orbiting in a polar orbit, so we pass over portions of the Moon in this polar orbit every day. And there are seven science instruments on board. There is a radiation detector, a thermal radiometer, a radar instrument bar, ultraviolet detector, a neutron detector, the laser altimeter, and of course the camera system, which I’m most familiar with. And that has the, the catchy acronym of LROC or Lunar Reconnaissance Orbiter Camera.

Host: Nice.

Julie Stopar: And so, there’s actually, it’s interesting because there’s actually two components to that system. So when you hear the word camera, you think, oh, it’s just a single camera, but it’s actually a set of cameras. There’s a wide-angle camera, which gives us wide field of view perspectives, and it’s also the basis for a lot of the global mosaics that you’ve probably seen out there. And there’s two narrow-angle cameras, which look a lot like, say, like a 10-inch telescope that you might have in your backyard, actually. And those two are pointed mostly down at the surface, and those give us the high-resolution images that you’ve probably seen. And those can give us details about on the human scale down to about 50 centimeters scale per pixel.

Host: Unbelievable. And so, so you’re, that’s a lot of great imagery. That’s a lot of different ways to capture that imagery. And so, high-level, what are some of the things that you’re working on when you, when you take a look at these images, what, what are the pieces of science that you’re pulling out to help describe the story of Moon, and, and find those interesting locations and, and like what, what are these, what are the, what are the stories that are, that these images are telling you?

Julie Stopar: Yeah, well, the, the thing that is really great about LROC is not only do we have these amazing global mosaics, which give us a very consistent picture of the Moon from place to place, but the, the high-resolution images really filled a gap in lunar knowledge beginning back when we, when we first started orbiting. Prior to that we had Clementine, Clementine and, you know, earlier lunar Surveyor, lunar orbiter, but this was really the first time we had a large volume of high-resolution images. So, like, there’s kind of funny story, like, just my first couple of years at the LROC operation center, I had the really fun task of sitting at the console and handling the images as they were downloaded from the spacecraft. And so, as part of that, I made it kind of my personal task to actually look at all of the images each day as they came down, and some of them were just like amazing to look at. And it was, it was so exciting because it was like the first time anyone had seen this particular image or this particular feature. And there, the one that really stands out in my mind is there’s this relatively young crater called Giordano Bruno, it’s a super-bright crater on the Moon. And the first high-resolution, high-resolution images we got of this crater, there’s, one of them showed this big glob and everyone was so excited when we saw it because it is just so different than everything else on the Moon that we had seen up to that point. And we looked at this glob and it looks basically like some honey had been thrown out of this impact crater and it had kind of dribbled down, down the outside of this crater. And we just sat there, like, staring at it like, oh my gosh, this is like the most amazing thing. And, you know, then of course like the science brain kicks in, like, OK, so what is this really? And started, you know, talking about it. And it’s like, oh, OK, so this is actually some impact melt; so, melted rock that was produced during the impact that was thrown out of the crater towards the end of this really dynamic, powerful impact event. And it just sort of oozed slowly down the outside of this crater. And, yeah, so that’s kind of like just an example of like, the power of some of the new images that we’ve been getting, just it’s really the first time we’ve had the amazing detail for a lot of these features.

Host: Unbelievable. Yeah, I want to explore that a little bit more Julie, but, but I, I want to go over to, to David for a second and talk about, some of your research as well. And, and it’s both of you have, doing very interesting things. David, what I found fascinating about some of your research is the cool places on Earth that you get to go to try to explain some of the fascinating things in the, in the solar system. So can you tell me about some of, some of the cool things you’re doing, some of the, some of the research you’re, you’re participating in for, for lunar science?

David Kring: Sure. And, and in fact, if I can actually capture that in a high-level, and explain to the audience that there are different ways to explore the geology of the, the Moon, and so Julie very eloquently a moment ago spoke about how we can use images to explore the geology of the Moon; in my own case, I use samples that were collected on the lunar surface, and on Earth I study similar geologic structures, as analogs to what occurred on the Moon. So I think what you were alluding to, there was my work with impact craters here on the Earth; the Artemis exploration zone is an impact cratered terrain at the lunar South Pole, and so it makes a lot of sense to study and understand impact cratering processes as they exist on the Earth because you can get to them a little bit easier. So I’ve done a lot of work with Meteor Crater, which is the best-preserved impact site on Earth. It’s very famously in Northern Arizona, it was used by Apollo astronauts for training, and I still take NASA’s astronauts there today for, for training. And then there’s, at the other end of the scale, the Chicxulub impact event, which occurred 66, which was produced 66 million years ago in the Yucatan of Mexico, and, and that particular impact crater we link to the extinction of dinosaurs and most life on Earth. And so, that’s a, that’s a, quite a different and dramatic example of, of impact crater on the, on the planet Earth. What’s fascinating is the Moon contains a record of even larger impact events, so some of the craters on the lunar surface are actually the size of continents.

Host: Oh, wow; awesome. So, so, so, so tell me about that. So tell me about, let, let’s start with some of the, you mentioned, you’re, you’re taking astronauts out to the Arizona desert. So, so obviously, and, and you started with making a connection to we can learn a lot on the Earth that could be applied to Moon, you know, research: basically, training, training the astronauts to understand what to look for and what to do. Tell, tell me about that. Tell me about, what, what you’re doing when you take astronauts out to Arizona and, and what, and what you can apply there that is good for doing research in space?

David Kring: The first lesson that astronauts learn is the topography of an impact crater terrain. It’s pretty dramatic. And so, astronauts, the first thing I do with the astronaut is, is we walk around the impact crater, and then we walk down into the bottom of the impact crater, and then we walk out of the impact crater. And, and that is not easy. And of course it now put, you put it in the minds that they have to do this in a spacesuit, they may have to do it in one-sixth gravity, but it is a challenging exercise. There is a metabolic load that is required and, and they must deal with, if they’re going to explore similar terrains on the lunar surface. But then there is, the second part of that education process is to understand the process of impact cratering, how the process of impact cratering samples the subsurface of the Moon and redistributes that material on the surface. And so the astronauts learn where in a crater or around a crater they should go to collect the best samples to answer the scientific questions that we have posed for them to address. And this was done with the Apollo astronauts, we continue to do it with NASA’s astronauts today, and I am sure that we’ll continue those training processes as we get closer to the launch of Artemis III.

Host: Very, very cool. Now of course, a lot of this training that’s happening on Earth is preparing for exploring the Moon as part of the Artemis program, and you referred to the Artemis exploration zone. I, I believe you, you pointed to the lunar South Pole. Can you tell me about that, that exploration zone and, some, some of the features about it that are interesting? Why of all the places on the Moon this is one of the, one of the places at least up front in the near term, that we’d like to explore?

David Kring: Yes. So the agency defined the Artemis exploration zone as being in the area within six degrees of the lunar South Pole. This is an area that both Julie and I have, have mapped; in fact, we have a wonderful atlas of, of the lunar South Pole online, if your listeners want to go looking for it. It is an impact crater terrain. It is a target of interest in part because there are very tall summits on the rims of craters and on the tops of mountains that are illuminated more than 50% of the time, and so they provide potentially solar power for astronauts in any habitats that they might deploy. This area of the Moon also has some very cold, permanently-shadowed regions that may have been, over geologic time, traps for volatiles: volatile elements and volatile materials like water or carbon dioxide. And these are materials that potentially can be harvested as resources. So, for example, water can be used and consumed directly by astronauts; water also can be used to shield astronauts from space radiation; and water can be separated into its oxygen and hydrogen components for rocket propellant. And so these are kind of the exploration drivers for targeting the, the lunar South Pole, for, for exploration. But scientifically, geologically, it’s also a fascinating terrain. As I said, it’s an impact crater terrain, it’s on the rim of the South Pole-Aitken basin, which is the largest basin on the lunar surface: this, this impact basin is 2,500 kilometers across, it’s 13 kilometers deep, and when you’re standing on the South Pole you’re standing on the rim of that basin. And, and as you look out from the South Pole, you’re looking at craters in size from a meter to several tens of kilometers, all produced on top of that South Pole-Aitken basin impact site. And so collectively, by going to that part of the lunar surface and collecting appropriate samples, you can unravel the bombardment history of the Moon, and by doing so unravel the bombardment history of the Earth, which has since been erased, and the bombardment history of the entire inner solar system. So, it is a geologic gemstone, if you will, in terms of the scientific insights that we can glean from that type of exploration.

Host: Yeah. If you understand, if, if this can truly reveal the bombardment history of the solar system, what does that help scientists reveal about, about the formation of the solar system? What, what gaps are we trying to fill with that knowledge?

David Kring: OK. There are, I would say three big ideas that come out, that, that actually derive in part from our analyses of the Apollo samples. In fact, so the, these are some of the scientific legacies of Apollo that we now know enough to pursue with more advanced questions. But, but one of those issues is the idea that the early Earth-Moon system and other inner solar system planets was severely bombarded in the first billion years. And you can see that the record of that bombardment when you look up at the Moon and the night sky from your own backyard, you see circular structures, most of which were produced in the first billion years of solar system history. And so by going to the Moon and collecting those samples, we can deduce the types of material that hit the lunar surface and the Earth’s surface, we can determine the ages, or the time in solar system history when those impacts were, were occurring, and the sequence and the cadence, of, of that impact history. Now interestingly enough, that period of bombardment coincides with the first evidence of life on Earth. And so there is a hypothesis, it’s called the impact-origin of life hypothesis, that suggests that that bombardment may be entwined with the origin of, of life on our planet. And if that’s the case, then potentially it’s entwined with the origin of life on other planets, such as Mars. The studies of impact cratering are also important because of its effect on the subsequent evolution of life on planets. I mentioned Chicxulub and, a very famous impact crater here on Earth; that crater demonstrated to us that impact events can modify, in dramatic fashion, the evolution of life on a planet…in that case, extinguishing most life on planet Earth, including dinosaurs, ushering in the age of mammals which eventually, of course, led to the human species. We’re also interested in that impact cratering record because impact cratering is an ongoing geologic process. It can and will affect Earth in the future, and so this poses a hazard; we want to understand those hazards so that hopefully we can mitigate those hazards in the future and prevent our own extinction.

Host: Wow. Lots of, lots of things you’re tackling there. That’s absolutely incredible. I, I want to, I want to focus on the lunar exploration site a little bit more and go to Julie for a second because one of the things, David, that you mentioned, is that both you and Julie are mapping, the, the Artemis exploration zone. And so, Julie, I, I wonder, you know, David pointed out a couple of interesting features about the Artemis exploration zone, scientific reasons why, why it is a very interesting place to go. As you’re mapping, one of the, what are some of the things that you are revealing about the lunar surface that, that would be very, good to know for the scientists, for the engineers, for the mission planners that are trying to, actually form a human mission at this, at the zone.

Julie Stopar: Oh, sure. Well, I think, mainly I would characterize my role in the mapping as presenting the data that LRO and other spacecraft and instruments have collected in visual ways that are easily accessible by mission planners and the, you know, the Artemis team, who are making those decisions on where is the best place to land and where is the best place to set up a base camp, and, you know, what are the hazards at these various sites. So all of that data, you know, comes from these different spacecraft. And particularly the, you know, LRO mission has collected a lot of the more modern data sets that are being used, like the high-resolution global topography, along with some special areas near the South Pole where they have specifically collected and iterated on their data, produced the highest quality products that they can. Also got high-resolution stereo coming from the LROC images themselves, so if you actually, if you have like, you think about what you would see at the surface in an image it’s, there’s going to be a lot of shadows near the pole, because the Sun is always low on the horizon, but if you do collect enough of those images you would basically see over the course of the year the Sun moving around the horizon, and so the shadows would actually basically rotate around the scene. So much of the scene can be illuminated over the course of the year, even if just very briefly; of course, not the case for the permanently shaded region. But taking all of that data together, you can produce a model of the surface and its topography and, and characterize all the hazards like the small impact craters and, and some of the larger boulders, which are relatively few, but we can identify those as well. And then of course there’s the thermal data set from the Diviner instrument, which has been used along with the topography to understand exactly where the permanently-shaded regions are and where areas in those shaded regions support trapping of water ice, the places are the coldest and, and forever dark, at least in the, in recent history, right, over geologic time. And so, with those, those are maps basically of possible resources that can be used, and taken into account when people are looking into where is the best place to set up a base camp they can, they can take into account what kind of, what kind of resources they need, what kind of science questions they want to address be it, what is, you know, what is the range of volatiles, what does it tell us about the beginning of the solar system, or if they’re looking more towards an ice deposit that might be useful for utilization purposes they might be looking for different characteristic.

Host: Hmm. Utilization, meaning like a resource that can be used to support a mission, like fuel or oxygen or something?

Julie Stopar: Right, right. So trying to extract it in larger volumes and then –

Host: Got it.

Julie Stopar: — you know, producing oxygen or something, water to drink, for example.

Host: OK. Yeah. And then, and then I think, David, you were mentioning like, you know, samples, so of course, there’s a lot of, one of the, one of the best, I think thing, one of the best scientific things about going to the Moon and having an Artemis program is that, David, you were mentioning the value of Apollo samples and actually holding, you know, like, like pristine, you know, samples of the Moon in your hands that were collected. And so, we have that opportunity again. And so, you know, Julie, Julie, and you guys are both mapping the, the, the surface and I’m sure you’re pointing out not only interesting sites and some of these things that Julie’s talking about, but you’re thinking, I want to get a hold of that: I want that kind of sample, because that’s going to, that’s going to reveal something interesting to me. So can you tell me about some of your work with samples so far: what, why they’re interesting, and then what some, what are some of the samples that you’re already thinking about for Artemis?

David Kring: Yes. So I think it’s very important for people to understand that the samples that the Apollo astronauts collected are just incredible treasures. And, and there’s oftentimes said in our community that they’re the treasures that keep on giving because, of course, with, as new analytical techniques are developed we can go back into that collection and reanalyze the samples. But the important thing to, to take away about that is, most of the big ideas that you hear about when you, when you tune into a Discovery or a PBS or a History Channel show about lunar geology comes from the analyses of those samples. So when you, when you hear about the giant impact hypothesis for the origin of the Moon, that comes from an Apollo sample or Apollo samples; when you hear about the lunar magma ocean hypothesis, or the lunar cataclysm hypothesis, or the impact-origin of life hypothesis, all of those come from analyses of these Apollo samples. And so, we, we now understand the value of landing on the, the lunar surface and collecting samples and bringing them back home to Earth for analyses. And so, yes, I’m very much looking forward to Artemis astronauts doing similar activities in the South Polar region of the Moon and collecting samples, and using the imagery that Julie’s team has been collecting over the last decade, we have identified specific boulders and soil site, sample sites, that we would like to direct the astronauts to. And, and that actually is an amazing thing: because of the imagery that Julie was describing is so good, we are able to do such high-fidelity studies that we’ve already identified rocks — specific rocks — we’d like the astronauts collect. I mean, it’s just the, it’s just stunning, and, so yes, we are making plans. Now the, the crews have not been selected, the Artemis science team has not been selected, so I may actually not have any role in those decisions or conversations but we’re at least doing all of the preliminary work that can be used as a, as a baseline or a foundation for those decisions in the future.

Host: And that’s part of the reason that I wanted to talk to you both today is because, you’re right, there’s still a lot of work to do to actually, you know, think about some of the science that we’re actually going to do, but the idea that Artemis is exciting the scientific community as much as it is, I think is a, a very valuable note: that you guys are putting forward a lot of effort ahead of time to think about something as specific as, of the entire lunar surface, a rock that you have in mind that you would like to as a, as a sample to bring back, because you’re just that excited, you’ve, you’ve done a lot of homework to, to pick out that rock. I, I bet. And that’s, and that’s really what I wanted to talk about today is — really just, the — science that can be, that can be had from some of these samples. David, you went, you described a lot about, I want to, I want to pull back some of the samples, the Apollo samples, and you described some theories that, that help us to understand the formation of, of the Moon, the formation of Earth, and really the, the, the history, the story of the solar system. Can you pull out a couple of those in specific that, that you have worked on, I think one of them is lunar cataclysm, I think, I think you’ve written some, you’ve done some research on that hypothesis specifically, but, but just give, to give our listeners some context on some of the grand stories of the universe that are being revealed from some of these samples.

David Kring: Sure. And let me, let me describe the cataclysm hypothesis and then, because it’s relevant to the South Pole, let me also speak about the lunar magma ocean hypothesis.

Host: Yes. Please.

David Kring: Beginning with that, that lunar cataclysm hypothesis, what, what we’re speaking about there is a potentially intense period of bombardment that occurred early in solar system history, notionally about 4 billion years ago. That idea emerged from analyses of Apollo samples when sample after sample after sample, when its age was measured, had a 3.9- or 4.0-billion-year-old age. And so, my, my mentors, my, the, the colleagues who taught me about lunar science, who were doing those analyses, deduced that many of the basins that you see from your backyard on the lunar surface were produced at that time, 3.9, 4 billion years ago. So they envisioned this really intense period of bombardment, and they called that the lunar impact cataclysm hypothesis. We’ve since, since showed that, that bombardment affected the Earth and planets throughout the, the solar system, so we sometimes refer to it now as the, the solar system cataclysm hypothesis. But the Apollo landing sites had no knowledge of that hypothesis when they, when they were selected, they were, we had no knowledge of, of that hypothesis, and, and of course we were constrained for engineering reasons to land on the near side, near equatorial region for safety. And so, the, we now know that there are better landing sites, better samples to collect, to explore that idea better; we, we, we still don’t understand the magnitude and the duration of that bombardment, in fact there’s a great debate about that within the lunar community. And so, we want to go to specific, other areas of the lunar surface to, to tease apart that, those questions. Now, the other big idea that I mentioned is the, the lunar magma ocean hypothesis. This actually emerged from Apollo 11. Neil Armstrong and Buzz Aldrin landed on a basaltic plain, again because it was a relatively flat and safe place to land, but in the soil they found these bright white particles of rock, which geologists call anorthosite. And there was no anorthosite to be found at, at the Apollo 11 landing site, and so the question emerged, where did those rock fragments come from? And well, they came from the mountainous highlands in the distance, and impact events on the lunar surface were throwing bits and pieces of those mountains all the way to the Apollo 11 landing site. Well, that anorthosite was a fascinating rock. In fact, it was my advisor, John Wood at Harvard University, that deduced that those were rock fragments that crystallized from an ocean of magma that used to surround the Moon. And, as it turns out, some wonderful samples of that rock, anorthosite, appear to exist in the crater walls of Shackleton Crater beneath the South Pole. And Shackleton Crater probably excavated some of that material and distributed it across the lunar surface in the vicinity of the South Pole. And so we’re very much hoping that the Artemis astronauts will collect some of that anorthocidic material, return it to Earth, so that we can probe this ocean of magma that used to exist around the Moon in greater detail.

Host: Unbelievable. So, it’s so exciting. You guys, you guys just seem so excited about just, just the possibilities that can reveal. And so, so Julie, I’ll continue this excitement, right, you you’ve done a lot of work with the LRO and the, and the cameras of the imaging. I’m sure you have your own research that you’re looking at, some of the, some of these questions that, that, that David’s posing, and so, and, and working on, I’m sure you’re doing some of the same things. Can, can you tell me about some of the, some of the work that you are doing, and some of the sites and, and features about the Moon that you’re interested in researching through Artemis?

Julie Stopar: Oh, sure. I was first just going to say, like, that it is absolutely energizing; like, everyone I talk to is so excited about Artemis landing and especially getting samples back. I mean, it’s, it’s not only exciting for our science community, but just general people that I talk to, lots of young people, super-excited about possibly being part of Artemis generation. Just lots of people requesting, how can I work with JSC? How can I work with the LPI? They just really want to get involved. And it’s, it’s just wonderful to see all of that excitement out there and it’s, it’s, it’s great. So yeah, I mean, David really touched on just one of the things that was so amazing, too, about the samples; like, they do keep giving. But it’s also such a fabulous story of like how just those few grains of soil in, in the early days of Apollo helped scientists like John Wood figure out the basic framework of how the Moon formed and how it evolved. And then each additional sample giving more and more context and telling us more about it, but also raising new questions. And even today there’s still things about the Moon that we don’t fully understand, like, some of the magmatic processes, which surely must be different than those on the Earth because the Moon is relatively dry compared to the Earth. So things like silicic volcanism, how can we get that on the Moon when we don’t have plate tectonics and let, tectonic plate interactions? And there’s just, it really speaks to like how geologists have to kind of think out of the box that we kind of grew up in, but also getting that new perspective, we can turn that around and, you know, it gives a new perspective on the Earth as well. So some of the work that was done on lunar volcanism, with the large flood basalts, the mare deposits, and then looking at that and how it compares to terrestrial basalt eruptions, and sort of in step these hypotheses about the processes involved in those eruptions kind of, kind of took stuff together. And so, these ideas about the Moon also help us evolve ideas about our own planet.

Host: Very interesting. Oh my gosh. Yeah. Yeah. And I, and I love that the, the excitement that you’re witnessing in the scientific community, that’s, I, I love that so much. And so, you, you mentioned samples too, and, and how exciting those are, and, and so, I kind of wanted to continue that conversation for just a bit, because I wonder, you know, what, what considerations should be, should be put forward for that sample collection, the actual task of collecting the samples? You can of course, scientifically point out the rock, which is amazing that you can do that, but then from a scientific perspective, what tools, what, what, what constraints are needed to collect the rock? So for example, if you want to preserve it, so if you want to, like, if, if you need to vacuum-seal it or, or put it in a very specific container or something like that, so, so David, is that something that, that you and your team are already thinking about — OK, we want that rock, yes, we’ve, we’ve pointed out that one, but, but when we get it, here, here are some of the ways that we would like it to be retrieved, like in terms of the tools and hardware that’s needed for the astronauts to actually collect it?

David Kring: OK. There’s a couple of different levels of answers to that question. And so let me, let me kind of step through them chronologically. So the, the first step is, is actually to train the astronauts to collect the right sample. And, and so you need to take them in the field to analog terrains, you need, which, which is basically, basic training, and then once a crew is selected there will need to be mission-specific training. And through the course of that training the crew will understand what the scientific questions are, and so when they are on the surface these now-very-smart assets will make good decisions as to what sample is collected that best answers those questions. And, and it’s, and it’s, I have to say it’s incredibly exciting to work with those individuals. As you probably know, our astronauts are just brilliant people, and, and it’s, it’s wonderful working with them and passing on our, our, our knowledge of geology so that they can make smart decisions during, during flight. But then there’s the, the second question, part of that question that you alluded to, and that’s the, what we call the curation issue. How is the sample handled? How, how is it returned to Earth? What happens to it when it is returned to Earth? And that’s something that I bump into because I analyze the Apollo samples, but I have to say that there is an entire group of, of experts on that — I mean, they are truly the world experts — right there at JSC. They’re in, in Building 31, it’s, it’s the ARES (Astromaterials Research and Exploration Science) group. And, yes, they had protocols in place for handling Apollo samples, they’re developing protocols for the Artemis samples, some of which will be different than Apollo samples. So for example, we’ve, we’ve bumped into a couple of times this notion of volatile materials in the South Polar terrain, and so techniques, potentially sample containers, will need to be designed for recovering and returning that material to Earth so that it’s suitable for analyses here. So, but, but that level of questions or that series of questions are really best addressed and best answered by, my colleagues there in Building 31. You, you also mentioned tools; the tools are basically going to be those of Apollo. You know, there will be scoops, there will be tongs to grab samples, there will be hammers, but these, these are fairly basic geologic tools, modified slightly because astronauts will be working in a pressurized spacesuit as opposed to shirt sleeves, which makes it a little bit more challenging. But, but the tools of Apollo were well-designed and won’t require a lot of modification.

Host: Understood. Let me, let me ask then, I mean, your, your, in terms of the sample collection, of course, when, when it gets, when it gets back down to, to the Johnson Space Center, to the ARES group, like you’re mentioning, for processing for storage and everything, you, of course, from the LPI, you guys want to get a, a hold of it; so what sorts of equipment, what sorts of tools do you have at your disposal so that when, when you get that sample, you have, you have the capabilities to research what you want to research?

David Kring: Oh; so I should probably explain that our institute was founded by President [Lyndon B.] Johnson and chartered by the National Academy of Sciences to help NASA with its Apollo program and to be an interface with the university community for the analyses of the Apollo samples.

Host: Got it.

David Kring: Since we are, we are so closely co-located with JSC, we actually use the instrumentation at JSC.

Host: Cool.

David Kring: And so, that instrumentation will involve a lot of what we call microbeam instruments, so we will use beams of electrons or beams of ions, either a cesium or oxygen, to chemically and structurally analyze those materials. We will use old-fashioned microscopes for assessing the textures and the mineralogical composition of samples. And, and I should say that that’s a fascinating little twist there. Most people, when they see our boxes of rocks, they say they’re just gray rocks, but of course, us geologists know better: we will make these microscopic-thin sections of them and shine light through them, and then they just illuminate, brilliantly, like stained glass in your favorite cathedral. The, the rocks themselves, once you look at them closely, are, are truly, spectacular. So we do most of that work at the Johnson Space Center.

Host: Amazing. Amazing. And you guys are the interface, that’s so cool. Well, well then, then I’d like to understand, Julie, from the actual, you know, when you’re talking about LRO and you’re talking about like getting these photos and monitoring them and working with a team and, and analyzing really cool, you know, the, this, that, that, lava drip that you were talking about earlier, what, what was, what, what are you actually doing, like, what is the setup, that, that you’re, that you’re, using to actually work with the images as they come down to support LRO?

Julie Stopar: Oh, yeah. Well, all of our images are processed and calibrated, and then they are actually released to the public within six months of us downloading them. So in terms of like helping other people with the images, the team will often, you know, give tutorials on how to, how to access the data or how to interpret it. But I was actually thinking while you, you all were talking was, you know, the samples are absolutely wonderful; they’re beautiful, like David said. And one of the really great things about samples is that they do compliment and they’re there for long-term studies, they are really great for answering specific kinds of questions, like very detailed questions about the history of the rocks and things that you need very precise instruments for. But also that the, the orbital data provide a different framework for discovery. And there’s certain things that just are, better assessed or better analyzed with the orbital data. So say, like, I think earlier in the conversation we were talking about, like the current impact rate and understanding if there’s any hazards associated with that, and so, actually, one of the things that is really amazing about the fact that LRO has been in orbit so long is we do have oodles — thousands, hundreds of, I’m not sure exactly but it’s a lot of data – of the surface, and some of that does get re-imaged again over time, and from those re-imagining events we are able to identify new impact craters that have formed on the surface since the last time we imaged it. So, and from now we can actually calculate what are the sizes and frequencies of the new impact craters that are forming, and look for, like, spatial patterns in their distribution. And so that is one thing that has really kind of transformed our understanding of like the current activity on the lunar surface in terms of meteorite bombardment and solar, solar radiation and weathering. But the other thing that you touched on, too, is the volatiles. So like David very eloquently said, we have a lot of experience from Apollo on how to handle traditional lunar samples, but that there’s probably going to be you some special samples, maybe those with volatiles, that we want to preserve in a very pristine state for detailed chemical analysis here on Earth. And actually, from my own research, one of the questions that has kind of been in my mind for years is, like, as we’ve started over the past decade or so understanding that the Moon is not entirely completely dry, but that there is some water there, there’s probably some pretty significant polar deposits, trace amounts of surface water nearly everywhere at least during some parts of the day, you know, it kind of occurred to me like why don’t we see any chemical of changes on the Moon surface as a result of that, especially in areas where we think it might have been, you know, to use this quote, buckets full of water, right? Like it happens nearly everywhere else where we see water there’s usually some chemical reactions. And so that was one thing that was kind of driving some of my research, and then working with some folks at JSC and Washington University to understand not only are there indicators on the lunar surface of where water and some of these larger deposits of volatiles might be, but also what happens when you bring back soil that contains some of these materials, what happens to the water ice, some of the other elements like sulfur, mercury, organics, and what do you really need to accommodate for in terms of sampling, the sampling method, how much do you need to preserve on the way back in order to answer the science questions that people are interested in answering? And so, that’s work in progress and there’s wonderful teams at JSC, and I think David alluded to a number of these groups over there that are just really experts in this stuff and they’re working on it. But for me, that’s like one of the things I’m actually, like, hoping to get, research-wise, out of this is understanding, like, so why, under what conditions would we see chemical changes on the lunar surface, or understanding like what effects our own disturbing of that material would have, in terms of our interpretations of, of those deposits?

Host: Both of you are, are, are just very, very transparently excited about all of this. And it, it’s, it’s certainly exciting me just listening to the possibilities that are opening up. So I wanted to, to close with some thoughts about the Artemis program, the importance of, of exploring the Moon, and then how that opens up the possibility for exploring more of the solar system. Just, ending with a thought of, of why, why this kind of science, why understanding more about the formation of the Moon, the planets, the solar system, is important for, for us as a species and, and for, for to, to have that sort of knowledge. What, what is the value that you see? I mean, you’ve, you’ve dedicated your careers to studying such fascinating things; I’m sure you’ve, you’ve put some thought into why this is important. David, I wanted to first toss to you; thinking about all of those things about, about Artemis, about, about this continued research, just why this kind of research is important and why this upcoming time is so exciting?

David Kring: And there, there’s a three-part answer to that question.

Host: Do all three, yes.

David Kring: The first, the first answer is that, as I’ve said earlier, the, the Moon has preserved an extraordinary geologic record over 4.5 billion years. And that record does not exist anywhere else in the solar system, not in the detail that it exists on the Moon. And so if you want to understand the early evolution of the Earth, if you want to understand the early evolution of Venus or Mars, you have to go to the Moon and study its geology. The second answer to that question is that if in fact we do want to go deeper into the solar system, such as Mars, we need to develop and test and be comfortable utilizing technologies in a deep space environment. And there’s no better place to do that than the Moon, which is just three days away. And so, lunar exploration, the Artemis exploration program, is going to prepare us in a way to safely go deeper into the solar system. And then the third answer to that question is that the, the excitement that, that you’ve noted that Julie and I have, we want that excitement to pervade society. I mean, I know, since I was a child at, during Apollo, that Apollo inspired a generation, and it didn’t inspire just people like me, it inspired people that went into computer technologies, that went into medical science, that went into a lot of different fields simply because they were inspired by Apollo and realized they could do anything if they put their mind to it. And I’m hoping that Artemis does exactly the same thing with a new generation of students, but in a more diverse way. I think that that would be a huge measure of success of Artemis.

Host: Wonderfully said, David, wonderful. Go ahead, Julie.

Julie Stopar: Yeah, I was just going to say, I absolutely agree with everything David said, and I don’t, I don’t think I could say it any better. Maybe, I would just, like, drop a hint to maybe people who are listening: you know, wouldn’t it be really awesome if we could make use of some of our more advanced computers and technology to actually involve the community and people and the public in this exploration with the astronauts on the ground in real time, or through virtual reality, so that we could all kind of go along with them and feel like we’re standing there on the surface, too?

Host: Yeah, yeah. Share, share the moment, even better than, than we’ve done before, and, and continue that inspiration that, that David was talking about. David and Julie, this was just such a, a fascinating conversation to have; there’s, there’s so much to unpack. I mean, we’re talking about all kinds of different science and possibilities that are coming up here in the very near future, and you guys are working hard preparing for that future. And, and it’s, it’s certainly inspiring and, and very exciting. So I want to thank you both, David and Julie, for coming on, representing LPI and, and the great work you’re doing over there in support of the Artemis program, and, and hopefully it inspires more of a movement in the scientific community to have that same level of excitement if it’s, if it’s not already there, which I’m sure based on what you guys are saying it, it might already be. But at least inspire some, some folks to go into this world. Thanks again, guys. Appreciate the time.

David Kring: My pleasure.

Julie Stopar: Yeah. Thank you. It’s great to be here.

[Music]

Host: Hey, thanks for sticking around. A lot of excitement in this episode. It’s really good to hear just how many of the researchers and the research community are excited for the Artemis program and what’s to come. Of course, you can always check out the entire program and, and see what the latest updates are, at NASA.gov/Artemis. If you want to check out just this podcast, we’re one of many at NASA.gov/podcasts; you can check out some of the other shows and you can also go to our website and check out our Artemis collection. Just click on the Houston We Have a Podcast link there at NASA.gov/podcasts, and off to left you can see our Artemis episodes. You can listen to any of them in no particular order. If you want to talk to us, we are on the NASA Johnson Space Center pages of Facebook, Twitter, and Instagram; use the hashtag #AskNASA on your favorite platform to submit an idea or ask a question for the show, just make sure to mention it’s for us at Houston We Have a Podcast. This episode was recorded on March 4th, 2022. Thanks to Alex Perryman, Pat Ryan, Heidi Lavelle, Belinda Pulido, and Jaden Jennings. And of course, thanks again to Dr. Julie Stopar and Dr. David Kring for taking the time to come on the show. Give us a rating and feedback on whatever platform you’re listening to us on and tell us what you think of our podcast. We’ll be back next week.