This Week in Space 224 Transcript

Please be advised that this transcript is AI-generated and may not be word-for-word. Time codes refer to the approximate times in the ad-free version of the show.

Rod Pyle [00:00:00]:
Hey, space fans! Starship Flight 12 is still floating. The Chinese are about to send hopping robots to the Moon. And we talk to Dr. David Kring of the University Space Research Association about how, where, and why the Artemis program will be doing science on the Moon. Stick around. Podcasts you love.

Dr. Rick Jenet [00:00:22]:
From people you trust. This is To It.

Rod Pyle [00:00:25]:
This is This Week in Space, episode number 224, recorded on August 21th, 2026: The Science of Artemis.

Rod Pyle [00:00:31]:
Hello everyone and welcome to yet another episode of This Week in Space, the Science of Artemis edition. I'm Rod Pyle, editor-in-chief of Ad Astra magazine, and I'm here with guest co-host Dr., Dr. Rick Jenet, who's the founder and CEO of Expanding Frontiers, Vice President of Technology and Entrepreneurship of the National Space Society, and also on their board of directors. So he's important to me because, uh, he's one of the people that waves his hands over my paycheck.

Rod Pyle [00:01:03]:
Hi, Rick.

Dr. Rick Jenet [00:01:05]:
Hey, Rod. Great to be here.

Rod Pyle [00:01:07]:
How are you?

Dr. Rick Jenet [00:01:08]:
Oh, not too bad.

Rod Pyle [00:01:09]:
I just, I just gave you an organizational promotion there. Um, today we're going to be speaking with Dr. David Kring from the University Space Research Association about the science of the Artemis program, what we're looking to discover, how we'll do it, where we'll do it, and a lot more. So I think you're really going to enjoy this one. But first, before you start enjoying yourselves, Let me put a crusher on your spirits by telling you a new space joke from listener Steve Werzer. Last week, an alien spaceship crashed in Las Vegas. When the police arrived, they found Elvis unconscious at the crash site. They rushed him to the hospital.

Rod Pyle [00:01:44]:
When he woke up, the doctor asked, how are you feeling? And what do you think Elvis said, Rick?

Dr. Rick Jenet [00:01:50]:
I don't know.

Rod Pyle [00:01:52]:
He said, I'm all shook up.

Dr. David Kring [00:01:56]:
Oh boy.

Rod Pyle [00:01:57]:
Okay, thanks for the, for the, the, the kind rim shot. I didn't deserve that.

Dr. Rick Jenet [00:02:03]:
Now the jokes are getting better, Rod. Uh, do you now?

Rod Pyle [00:02:08]:
I've heard that some people want to shake us at Adams this joke time in this show, but you can help, please, by sending us— and actually, Steve, I appreciate that, that was a pretty good one. Um, but you can send us your best, worst, or most indifferent space joke at twistedtwit.tv. And we'll tell it on the air and we'll blame it on you if it goes over like some do. All right. But for now, let's do an abbreviated headline news.

John Ashley [00:02:39]:
Headline news.

Rod Pyle [00:02:41]:
Oh, there you go. Thanks for that, John. So, gosh, Rick, Starship test number 12 and the Starship itself, which touched down in the Indian Ocean but did not explode. Shockingly, has been at sea for a long time. I think it's been at sea longer than some freight journeys take. And shockingly, they've actually been able to keep it in one piece while they slowly towed it back. And I gather it's now sitting just offshore at Christmas Island near Australia, is it? Or New Zealand? Australia. So I guess it's kind of important that we get a look at that, at the very least, so they can see what happened with the heat shield, right?

Dr. Rick Jenet [00:03:21]:
I think that's one of the key issues. I also just think of the amazing engineering feat that went behind that, that it's still keeping water out. It's never easy, especially saltwater and saltwater conditions. So kudos to the engineering team there for what they did.

Rod Pyle [00:03:42]:
Yeah. And structurally, obviously anybody who knows anything about engineering knows this, but you have to construct these things very lightly. It's always shocking When I see a genuine spacecraft and get in there and start knocking my knuckles on things, they're lightly constructed because they're rockets and they have to fly and they're supposed to carry a ton of fuel. So it's a bit surprising when you actually start, you know, you go to something like the Apollo lunar module and put your finger, which I've done once, I wasn't supposed to, on the main pressure hull and go ba-doink like that because, you know, a lot of parts of it are pretty thin. And Starship is a big, thin stainless steel structure. So kudos to SpaceX engineering for keeping that thing in one piece. And fingers crossed their next test flight.

Rod Pyle [00:04:29]:
All right.

Rod Pyle [00:04:30]:
And we coming up, we have the launch of China's next great robotic mission to the Moon, Chang'e 7. Which in this case has a lander, a rover, and a hopper. And where are they going?

Dr. Rick Jenet [00:04:44]:
So I'm very excited about this mission. I think China is once again going to show its prowess in lunar exploration and just how far that they are able to succeed. And they're going to go to a permanently shadowed terrain. First time, at least in my memory and background, first time that humanity will have ever done anything like this. So it's going to be pretty exciting to see what they find.

Rod Pyle [00:05:14]:
Yeah, it is. And each of these missions gets more and more ambitious. And, you know, there was a lot learned by the Soviet Union and the US back in the '60s and '70s. I always rant about this, you know, that you can borrow the technological know-how from. But the Chinese have taken that, as they often do with technology, and really honed it to a sharp edge and are doing amazing things, new things with each mission, not the least of which was being the first to land something on the far side of the Moon and put up the 2 Magpie communication satellites so they could actually talk to it, because otherwise you can't do that. So this would be impressive. And also, nobody's done a hopper before.

Dr. Rick Jenet [00:05:55]:
That will also be—

Rod Pyle [00:05:57]:
It was planned but, but never happened. I don't know how, how much fuel it carries and how long it could do what it does, but in the lower gravitational field of the Moon, that's going to be a very cool thing.

Rod Pyle [00:06:08]:
All right.

Rod Pyle [00:06:08]:
And lastly, we have the whopping big National Space Transportation Policy that came out earlier in the week, I guess.

Dr. Rick Jenet [00:06:17]:
I think it was yesterday.

Rod Pyle [00:06:18]:
Oh, was it yesterday?

Dr. Rick Jenet [00:06:20]:
Yeah.

Rod Pyle [00:06:21]:
Tell us what it said that caught your eye.

Dr. Rick Jenet [00:06:24]:
So the administration wants US infrastructure to support more than 1,000 launches and reentries per year by 2030. That is an exciting number.

Rod Pyle [00:06:37]:
It sounds kind of like an arbitrary number in some ways.

Dr. Rick Jenet [00:06:41]:
Well, it is 1,000. It's not like 936.2 or something like that, but it's definitely a nice round number. It's hefty, but if they're going to take commercial space seriously, if we're going to take you know, humanity and the United States developing a space presence, we have to move into this phase where we are doing hundreds of launches on a monthly basis. So, you know, I guess we can all say it's like, well, is this real? Is it not real? But at least there's a goal in place and at least it's being discussed at the highest level. So that's what I'm— that's what I see as being exciting, that this is actually being discussed seriously. And setting, you know, drawing the line and setting the goal.

Rod Pyle [00:07:36]:
So now I often get a bit of a slapdown if I say anything political on this show, so I try not to. But what puzzles me is these kind of directives coming from, in an era, let's just say, where NASA was basically shoved in a box, shaken up, and then half of it poured out and left to rot in the sun. and the 70% or so of the agency that's still in place and effective— that's a very gross guess— you know, is now charged with this new thing. I mean, I'm all for it, but if you're going to do that, it's probably not the best thing to jettison 20%, 30% of your top people and your most senior minds. You can argue that, you know, there were some people that probably needed to be cycled out.

Rod Pyle [00:08:25]:
You see that in any endeavor, whether it's private industry or government.

Rod Pyle [00:08:29]:
and that, uh, you know, you want to bring in young blood. But that wasn't the directive here. It was just cut, cut, cut, trim, trim, trim, doge, doge, doge. And a lot of people weren't replaced until recently, and we're still seeing the beginnings of this. Jared Isaacman said, okay, you know, we're going to stop working with so many contractors and bring more people back in on staff, which is fine, but it kind of puts them back where they were in a slightly different way, if that makes sense. any thoughts on this?

Dr. Rick Jenet [00:08:59]:
Well, it's, it's interesting that it's— is this is a US national space transportation policy. So, um, I think what you're pointing at is it— they're not going to necessarily lean on NASA to do this. And what they're hoping is that the commercial entities are the ones that take up, uh, that take this up. Uh, and we, we do need, um, we know we need, um, dissimilar redundancy in our launch systems. Uh, so we have to promote it somehow. Um, and until, uh, we get to, uh, commercially sustainable business plans for space development, uh, the government is going to be funding this somehow, uh, one way, one way or another. And I kind of see this as a move in that direction. It's like, all right, let's put, you know, let's at least say that this has to be, you know, this, we need to have the infrastructure to support this.

Dr. Rick Jenet [00:09:47]:
And this is coming from, uh, you know, from it, from the administration, or at least from that level.

Rod Pyle [00:09:53]:
Yeah.

Dr. Rick Jenet [00:09:53]:
Uh, how exactly it gets implemented, that's going to be the interesting the interesting question. And does this mean this is going to promote other launch systems and other launch companies coming into this space? No pun intended. I hope that it actually does. And in some sense, like what you said, a lot of very good minds were let go from government service because of this. A lot of them might actually find homes in some of these commercial companies. these commercial entities. So overall, I think it's— I definitely think it's a positive thing for space development.

Rod Pyle [00:10:32]:
You know, that last point of yours kind of strikes home for me. I was talking to some senior people at JPL recently, and one of the— and they were not trash-talking private industry at all. In fact, they're all in favor of it. And NASA's been kind of pivoting this direction since about 2010, where they want to use more and more private vendors. What we have suffered from a bit though, intuitive machines, uh, was a little bit of what, what I and other people would call hubris on the private side when designing, say, something that's as thought to be as simple as a new lunar lander.

Rod Pyle [00:11:12]:
You know, we have a lot of engineering knowledge starting from the 1960s when the Surveyor spacecraft with nice wide footpad stance and a low center of gravity landed on the moon and stayed upright. And then we had a series of missions that landed on the moon, didn't stay upright, and there seems to be a failure of learning there. And a number of the NASA people I've talked to are on advisory boards, for instance, with some of these organizations and have said, you know, you might want to look into this and look into that. And in some cases, those suggestions were warmly embraced, and in other cases My sense indirectly is that they got kind of a, yeah, that's nice. Don't worry your pretty head. We're young engineers and we like to move fast and break things. The problem with breaking things in space is it's really expensive. It's not Facebook where you have a software error that you can then round off a couple minutes later.

Rod Pyle [00:12:06]:
It's obviously all the way out to the moon, lunar orbit, on the surface or near Mars or something.

Rod Pyle [00:12:12]:
And when things fail out there, it costs a lot. So I guess what I'm whining about here is I would just like to see a little more embrace of the hard-won knowledge of the first space age when we learned how to do this stuff. It was expensive as hell, but there's a lot of knowledge there that can be scooped up and you don't always have to do it in a new, bright, shiny way.

Dr. Rick Jenet [00:12:33]:
All right. Well, you know, humans are— humans are always going to fall into the trap of hubris. That's just— that's just what's going to happen. But hopefully, like you said, it's not— it's not Facebook where you can just, you know, throw something together see if it works and, you know, fail fast. But I do think we have to get ourselves— if space will really take off when we are at that point where we can iterate very fast and we can try different things out and the cost isn't there that much. Hopefully, you know, in the next decade or two we'll be at that point, and then things will really, will really take off. But I think that's— that is an important point of us moving forward, um, in this thing, is that we do have to learn how to fail fast and fail often. And some might claim that the current success stories we're seeing live that mantra.

Rod Pyle [00:13:25]:
Where might you have encountered hubris in your recent career, Rick? No, I don't want you to answer that. I was just kidding. That's a rhetorical question. All right. We will be back in just a few minutes with Dr. David Kring, so stay with us. And we are back with Dr. David Kring, who is the principal scientist for lunar programs at the University Space Research Association.

Rod Pyle [00:13:47]:
And director of the NASA Space Imagery Center at the Department of Planetary Sciences, Lunar and Planetary Laboratory, University of Arizona. Is that second credit past tense or present tense?

Dr. David Kring [00:13:57]:
That's past tense, so you want to scrap that.

Rod Pyle [00:14:00]:
Okay, did I miss anything though?

Dr. David Kring [00:14:02]:
Uh, so the USRA title is good. You could add that I was recently a fellow at the Harvard-Radcliffe Institute And Cambridge, Massachusetts.

Rod Pyle [00:14:16]:
Well, it doesn't sound to me like you need any more credits, but clearly you have them. And as I was scrolling down the page of your achievements, I thought, I need to pick 1 or 2 of these instead of the 10 or 20 that, that are listed here. But, uh, thank you for joining us today. We do appreciate it. We're here to talk primarily about the science of the Artemis lunar landing program, what we want to do, what we want to learn, and how we're going to do it. Uh, so I guess I'll start with the fact that the USRA has conducted lots and lots of research on this topic and generated a number of, of important papers. Um, so maybe we could start with where we go. What, what characterizes in your mind a good candidate for a lunar landing site besides safety and geological interest?

Dr. David Kring [00:15:03]:
Oh, um, well, when you've select the final landing site, of course, you have to take into account not only the scientific objectives, but, uh, what the hardware can accommodate and where that hardware and crew capabilities are in the development of a new era of lunar surface exploration. Um, there's, there's two— from a scientific point of view, there's, there's two ways to look at this. One, Uh, during the Constellation program, which preceded Artemis, um, NASA went to the National Academy of Sciences and asked, what are the nation's science priorities? And they produced a wonderful document. It was published in 2007 called, um, uh, roughly, uh, The Scientific Objectives for a New Era of Exploration on the Lunar Surface. And we actually spent 6 years, um, evaluating that document and where on the lunar surface that you could accomplish that science. And we did something completely unique. Uh, we did it objectively. That is, there were 8 goals and about 35 investigations in that report.

Dr. David Kring [00:16:17]:
And we took each one of those investigations and we said, where on the lunar surface can you address this investigation? And, and there's, you know, dozens if not hundreds of sites for each one of those investigations. And at the end of that 6 years, we then stacked those maps And we asked ourselves, where could you accomplish the most science, uh, and, and the most high-priority science? And the answer was the Schrödinger Impact Basin on the lunar far side. Uh, and so from a purely academy-level science perspective, the Schrödinger Impact Basin is, is where we should be going. Now, that's not where we're going. Uh, the Artemis program, uh, Uh, was languishing in schedule. And so, uh, the vice president of the nation says, well, I'm gonna help you out. You're going to land at the lunar south pole. And so, uh, the Artemis exploration zone, at least the initial Artemis exploration zone, is within 6 degrees of the, of the south pole.

Dr. David Kring [00:17:20]:
And knowing that, we've now conducted, again, 6, 7, maybe even 8 years now, studies of that region. And published, uh, as you noted, about 2 dozen peer-reviewed studies of potential landing sites in that area. The science is going to be different. That's all there is to it. And we could talk more about those science objectives if you would like.

Dr. Rick Jenet [00:17:42]:
So I'm curious, we— of course, there's always a scientific value and how we're using resources to get the most science. And that was one particular approach that you were just mentioning there. But then of course you mentioned another one, which was NASA said this is where we're going, which I think is an interesting piece there. I'm curious, what do you think is driving that? Is it other— is it resources, commercial, water?

Dr. David Kring [00:18:10]:
Yeah, well, actually it was the Vice President, not NASA, that said where we're going, and NASA's—

Dr. Rick Jenet [00:18:14]:
Oh yeah.

Dr. David Kring [00:18:15]:
And so we're going to the lunar south pole polar region, at least as it's configured today. As we speak, there are discussions of maybe landing elsewhere for the first or second mission. But, but at the moment, um, we are targeting the, the, uh, lunar south polar region, and that was driven in part by resources. And there's 2 different types of resources that NASA has now highlighted. Uh, one of those is solar power. Um, in, in the south polar region— Actually, let me take a step back. Uh, During Apollo, we were landing in the equatorial region on the near side. And in that portion of the Moon, the Sun is rotating overhead every 28 days.

Dr. David Kring [00:19:07]:
And so you have 14 days of daylight and then 14 days of darkness. And that 14 days of darkness is a challenge to survive. And so the polar region is attractive in that the Sun is orbiting the polar region just a few degrees off the horizon. It doesn't set unless it passes behind a peak. And so, there are locations in the South Polar region where sunlight is, is, is always present for 86% of the time. And the duration when you do not have access to solar power are quite short. And that's attractive to mission architects. The other resource I want to— the solar resource is a known.

Dr. David Kring [00:19:57]:
It's there. How we harvest it, how we distribute it are issues I think that are still being worked out. But there's another resource that is a potential resource, and it's going to take some exploration to verify its presence and whether it is actually recoverable. And that is volatiles. So, there have been models since the 1960s that in the polar regions, there are permanently shadowed areas where the temperatures are quite cold, and volatiles like water ice and carbon dioxide ice, dry ice as you know it, and other gases might be trapped. And if that's the case, that would be very useful. So, for example, the water. If water could be recovered, that would obviously be useful as a crew consumable.

Dr. David Kring [00:20:55]:
Water is a very useful shield against space ionizing radiation. And third, you can break up the water and form rocket propellant, which can move you about the lunar surface or take you off the Moon to deeper solar system destinations. So those are— those resources, or potential resources in the case of volatiles, I think are what's driving a lot of attention in the South Polar region.

Rod Pyle [00:21:25]:
We're going to go to a break in a couple minutes, but just a short one. What's very attractive about the Schrödinger Impact Basin?

Dr. David Kring [00:21:35]:
Schrödinger Impact Basin, it's a marvel. Well, first of all, in that original NRC 2007 report, the highest— the first and second highest priorities for lunar science was to test the idea that the Moon and the Earth and the entire inner solar system had been severely bombarded by asteroids and comets early in solar system history. And so to test that, you actually need to go to some basins and determine their radiometric ages. And the Schrödinger impact basin is the second to the last basin formed, and so it has not been overprinted by impact events that occurred later.

Rod Pyle [00:22:16]:
Right.

Dr. David Kring [00:22:17]:
That is the things that has vexed us with the Apollo samples. They're messed up. And, and, and in addition to being— Schrödinger being the second youngest, it actually is within the largest impact basin on the Moon, the oldest impact basin on the Moon, which is the South whole Aitken Basin. And so we're hoping in one location to get the ages of both. And then later, the volcanism spewed lavas and pyroclastic material out on the surface. Our calculations indicate that that is the largest indigenous source of volatiles in the South Polar region. So if we do find them in the South Polar region, many of those volatiles in fact may can come from Schroedinger. And basically, most of the objectives in that NRC 2007 report can be addressed.

Dr. David Kring [00:23:10]:
They may not always be resolved, but you can address a majority of those NRC 2007 objectives within the Schroedinger Impact Basin.

Rod Pyle [00:23:21]:
All right, we're going to go explore our way into a break, so we'll be right back. Go nowhere.

Dr. Rick Jenet [00:23:27]:
Well, David, first off, I didn't get a chance to say before I started asking questions just how excited I am that you are here to join us. And I definitely enjoyed learning more and more about what you've been doing in your career. It's been very exceptional, to say the least. And I really thank Rod for giving me the opportunity to be able to talk to you about these. everything that's going on the lunar surface and so forth. Something that you may be aware of, of course, is the United Nations Office of Outer Space Affairs and the Committee on the Peaceful Uses of Outer Space. And in that is this committee of ATLAC, which is the Action Team for Lunar Activities Consultation. So we know that lunar surface exploration is heating up, if you will.

Dr. Rick Jenet [00:24:20]:
And there is a very interesting conversation at those levels which has to do with protecting science on the lunar surface. And I'm curious to see what your thoughts are about, you know, is— do we need to have protected zones on the lunar surface to protect science? Or is it, you know, is it not necessary? Is there another way of doing that? Or, you know, anything? I'm just curious about what your thoughts might be there.

Dr. David Kring [00:24:49]:
Um, that's a tangled area. It's a little bit outside of my expertise. Um, I, at the end of the day, I think the answers to those questions will depend on how many missions to the lunar surface there are. And, and we can talk about that on an annual basis or a decadal basis, because each one of those landers is disturbing the lunar regolith. And not only is it disturbing it in the local area of the landing, that, that material gets plumed and, and can be distributed globally. Okay, and so that can have a consequence on areas far, far, far from the impact, uh, the, the landing site. And that is particularly true for the largest landers. Uh, so we, we did do a calculation, uh, and, and I have to acknowledge that this is a preliminary calculations because we, we don't yet know the, the final specifications of the SpaceX Human Landing System, but that appears to have a dramatic pluming effect and will definitely distribute material globally.

Dr. David Kring [00:25:59]:
So, you know, we can refine those calculations once we better understand what that lander's final configurations will be, but that preliminary calculation illustrated immediately that this has a potential consequence for landing sites far, far from your base of operations. And then there is— there has been in the meetings that I have attended discussion of recovering a lot of these components such as, well, volatiles of various types. And Then the question is, how do you recover those volatiles? And if you are doing basically the equivalent of shaft mining, the consequences will be rather limited. If, on the other hand, you are having to strip mine multiple hundreds of kilometers of the lunar surface, that's a completely different— ballgame. And we don't know between those extremes where reality will land. So I'm glad that the conversations are going on. And because that means people are mindful of the potential problems, and they will monitor those activities and see where they do in fact land and what the potential consequences are. I don't know that you— we have the capability to make rules or regulations without better understanding the scope of the activity.

Dr. Rick Jenet [00:27:40]:
No, fair enough. Fair enough. And no, I agree that it's exciting to be living in a time where people, delegates, state actors are at the point where they feel it is necessary to have these conversations. But I guess going back to something that I'd love to hear your opinion on related to the science. And I'm sure being an astrophysicist myself, there's always kind of the, man, the Holy Grail. Be like, this is the thing that I would love that we could see or discover that could really change like everything. Do you have something like that? But like here, like this will change lunar science or?

Dr. David Kring [00:28:20]:
No, I mean, this, We have explored a very tiny portion of the lunar surface. And so basically the Artemis Exploration Zone, or any place on the far side, uh, with the exception of the small region that, that China had recently explored, is, is unknown. And, and so anything we do is by definition going to be exploration and, uh, in a land of discovery. And, and I don't know that you can predict what those discoveries will be.

Dr. Rick Jenet [00:28:50]:
Mm-hmm.

Dr. David Kring [00:28:51]:
What I can say is, that Apollo demonstrated that the key to transformational science is the collection of samples by well-trained astronauts and the return of those samples to Earth. Because it's, it's only in our terrestrial laboratories where we tease them apart. And, and so just think about the big ideas that you, you hear about on the Discovery Channel, the Learning Channel. It's the giant impact hypothesis for the Earth-Moon origin. It's the lunar magma ocean hypothesis, that is the idea that the Moon was once surrounded by an ocean of magma. It's the lunar cataclysm or inner solar system cataclysm hypothesis. And that one's huge. I mean, not only has that one taught us that all of the inner solar system was being blasted, including Mars, But that may have been prompted by the accretion and orbital evolution of the outer solar system planets.

Dr. David Kring [00:29:54]:
And so—

Dr. Rick Jenet [00:29:54]:
Mm-hmm.

Dr. David Kring [00:29:55]:
The record of those events, the record of those processes are best preserved on the Moon. Uh, and so it, it's an extraordinary place. And so I think that one of the, the key things that we have to remember is that samples have to be a high priority. And right now, sample return is not a high priority. And that, in my mind, threatens a capability of outstanding Artemis science.

Rod Pyle [00:30:27]:
That's very interesting. Why don't we quickly bombard our way into a break and we'll be right back. Stand by. So, David, we're talking about the South Polar region of the Moon, which has some unique challenges. You've got eternal sunlight in some areas and eternal shadow in some other areas and brief periods of transition in some other areas. But it's real— really very different in those ways, survivability in particular, but also visual acuity and so forth, the Apollo landing sites. But in your mind, having studied this extensively, what are some of the unique challenges of pursuing the kind of science you want to do in a polar region versus what we did with Apollo? And how will that be different from what we did during the Apollo program?

Dr. David Kring [00:31:13]:
Well, one of the first things I try to explain to the engineers at the Johnson Space Center and those in the astronaut office is that the topography in the lunar South Pole region is huge. I mean, it's just, it is almost mind-boggling. So the South Pole is sitting on the rim of a crater called Shackleton. That crater is 3.5 times deeper than the Grand Canyon. Not too far away is a mountain summit called Malapert, and that towers higher than Mount Everest. Okay, and so within very, very short distances, you have just an amazing— I almost say an amazing amount of topography that I explain to people in public lectures. If it occurred 3rd on the Earth, it would be a national park. It's just— it's going to be incredible.

Dr. David Kring [00:32:10]:
So topography is going to be a challenge. Climbing hills, it's going to be a problem. I'm not too worried about the light or the shadows. I think the topography is the bigger issue from an operational point of view. Now, from a scientific point of view, that, that south polar region is far more ancient than the Apollo sites. That's exciting. We'll probably collect samples of rock from an earlier phase of lunar evolution than we saw in, in the Apollo sites. But it also means, and we learned this from Apollo 16, Mm-hmm.

Dr. David Kring [00:32:56]:
2016, that repeated impact cratering, which is what you have in those ancient terrains, really makes it difficult to tease apart the geologic stories. And that's one of the attractiveness of Schrödinger. It's late, it's simple, we'll get the answer, it'll be clear. There's going to be a lot of debate, uh, and I suspect some heated debate amongst scientists analyzing Artemis samples from the South Pole region because of the complexity that, that impact, those impact cratering processes produced in that region.

Rod Pyle [00:33:37]:
Well, you mentioned Apollo 16. I wanted to mention that that is the mission during which we had the most elevation change in those explorations. The longest EVA on Apollo was about 8 hours. But the highest they ever got, or the most elevation change they ever had, was 500 feet, which is a far cry from the kind of dynamics you're talking about doing double and triple the Grand Canyon. So this is going to be quite, quite different in scale than what we did with Apollo, isn't it?

Dr. David Kring [00:34:05]:
Yeah, well, yeah, so they're obviously— the astronauts are not going to be able to walk into those depths or to those summit horizons. So they'll be limited, uh, in their excursions. And, you know, the walking EVA limit is currently 2 kilometers. At the moment, Artemis does not have the communication capability to allow them to go 2 kilometers. Um, now, once we get mobility assets on the lunar surface, uh, the, the distances that crew can go might be 10 or 20 kilometers from a landing site. The objective is as mission cadence increases, is to land those mobility assets, let the astronauts use them in that area, bring the crew home, and then teleoperate those assets to another location. And those mobility assets will do the climbing. And then the astronaut, once they're in their new location, the astronauts can land at that alternative landing site.

Dr. Rick Jenet [00:35:07]:
Mm-hmm.

Dr. David Kring [00:35:07]:
And in fact, uh, we were asked by NASA to do a very lengthy, um, traverse study, um, across the, the South Polar region into the center of the South Pole-Aitken Basin on the lunar far side, uh, uh, with that type of, um, architecture in, in mind. And we did find a route where 2 crew rovers could traverse that entire distance Uh, and then the, the crew could meet those rovers, uh, in 5 different locations and, and conduct independent short-term missions at those locations.

Rod Pyle [00:35:44]:
That's interesting.

Dr. David Kring [00:35:45]:
Rick?

Dr. Rick Jenet [00:35:47]:
Well, I'm curious, um, how much of the, uh, of this, of the Artemis planning, uh, these traverses and so forth, do you think should be done in advance, and how much should be left to, you know, the, the actual astronauts on the ground and, you know, using their own judgments when they're there?

Dr. David Kring [00:36:03]:
Oh, the, the, the basics of the traverses initially will be laid out, I believe, by the geologic team, uh, working with the crew. And— but the astronauts will, at the scale of features visible to them and only them, will then be making independent, uh, uh, decisions. And that's why they have to to be well-trained. I mean, it's, it's absolutely essential that we utilize all available data in initial traverse planning, that the geology team supporting the astronauts themselves have well-documented experience, and then third, that the astronauts themselves are, are well-trained, uh, for the type of missions that they're going to be conducting.

Rod Pyle [00:36:55]:
So you've done a lot of work on craters, everything from Chicxulub, which is the big dinosaur killer down in Latin America, which is about 120 miles across, which is large, down to Meteor Crater in Arizona, where you've done some significant work. And my understanding is that, you know, one of your conclusions was that the Arizona Meteor Crater, or Barringer Crater, as it's sometimes called, Is a good analog for studying how to do this kind of work and these kind of traverses. Have you, have you done that work there?

Dr. David Kring [00:37:26]:
Yeah, no, absolutely. Um, it was not surprisingly, it was used by Gene Shoemaker during Apollo to train the astronauts. Um, and, uh, it's a crater, by the way, for those who know Apollo, it's very similar in size to North Ray Crater at the Apollo 16 landing site, about a little over 1 kilometer in scale. And, um, I've trained most of the flight-active astronauts when they were candidates, uh, at Meteor Crater. Uh, and, and yes, it's, it's wonderfully preserved. Anybody who wants to get some sense of what it's like on the lunar surface should visit Meteor Crater. But one of the things I point out to the astronauts is that topography is king. So if you go in and out of that crater, you better understand what you are asking crew to do if, if they were to go in and out of a crater of that size.

Dr. David Kring [00:38:16]:
If you listen to the voices of the Apollo 16 crew, they had no interest, uh, in going into North Ray Crater. In fact, they were a bit, um, uh, they didn't even like getting close to the rim. Uh, but, uh, the other thing that I point out, uh, when we're on the rim of Meteor Crater is going back to the Apollo 16 landing site.

Rod Pyle [00:38:36]:
Mm-hmm.

Dr. David Kring [00:38:36]:
is that in the immediate vicinity of North Ray Crater were 2 other craters exactly the same size. Well, we have this false sense of crater density on the lunar surface— I mean, on the Earth's surface because they are so easily eroded and buried and otherwise destroyed, whereas they've been accumulating for, you know, over 4 billion years on the lunar surface. And so astronauts, as I, as I explained to them, They will not be able to take a single step on the lunar surface without stepping into or onto an impact crater. It's just impossible. And so any operations on the lunar surface have to understand the fundamental processes of impact cratering and what it does, uh, to, uh, that, that surface.

Rod Pyle [00:39:26]:
Well, that sounds like a bit of a challenge, and I, I do remember 'Cause I'm old, listening to the EVAs for both Apollo 15 and Apollo 16. And what I remember about Apollo 15 was Dave Scott kind of encouraging everybody, hey, we really ought to drive a little further down into this ravine. And Mission Control saying, eh, we might wanna think about that a little bit. And at one point the rover started to tip and I think it was Irwin had to put his foot on it to hold it in place. These are my recollections anyway. But it was, it was a pretty exciting time. But again, in terms of the magnitude of what you're talking about here, not, not quite as ambitious. Let's run to a break and we'll be right back.

Rod Pyle [00:40:07]:
So stay with us.

Dr. Rick Jenet [00:40:09]:
Okay. Well, so when we, when we hear about craters and impacts and so forth, we know that in one way or another this affects life, or at least it had affected life on Earth. And I'm curious about whether the moon can tell us and the impacts on the lunar surface can tell us anything about how the, the, how such impacts helped life begin on the Earth's surface?

Dr. David Kring [00:40:34]:
Yeah, you know, early in my career, our team found the Chicxulub impact crater, which is key to the impact mass extinction hypothesis. And what I realized as I was studying those Chicxulub rocks is that they, the impact also generated this vast subsurface hydrothermal system. beneath the floor of the crater. And it occurred to me during the early solar system history when the Earth was being just bombarded by asteroids and comets, that those impact events would sometimes completely vaporize the seas, or simultaneously producing these vast subsurface hydrothermal systems beneath the surface. And those are perfect crucibles for prebiotic chemistry and the early evolution of life. So that's the impact origin of life hypothesis. Now, we've been testing the heck out of that. In fact, just this morning, I was adding up how many papers we have.

Dr. David Kring [00:41:33]:
35 papers have tested that hypothesis. And we've shown that microbial ecosystems can exist within and below the floor of the Chicxulub impact crater. But to then take that model back in time, you want to better understand the cadence of impact cratering. You want to understand the magnitude of those impact events. And ideally, you'd like to understand the composition of the impactors producing the craters. So, so at the moment, what we have gleaned from our studies of the lunar surface is that at that time, 85% of the impactors were asteroids and about 15% were comets, which is basically the same values that we have today. We've also, by looking for fragments of these impactors in the lunar soils from the Apollo sites, they seem to be concentrated carbonaceous chondritic type of meteoritic materials, which are the ones that carry the sugars and the amino acids and so on and so forth that you oftentimes hear about in the news. Now, we've only collected those types of samples from a few areas on the near side of the lunar surface, so we would certainly like to look for those types of materials elsewhere, such as the south polar region of the Moon.

Dr. David Kring [00:42:58]:
The other thing that's— it's a tease. You know, during that period of bombardment, things were hitting the Earth at the same time they were hitting the Moon, and some of that material was getting jettisoned from the Earth and hitting the Moon. And so the oldest fragments, the oldest surviving fragments of the Earth may be on the Moon. And in fact, uh, in 2015, we actually published a paper. We think we found one of those fragments at the Apollo 14 landing site in one of the Apollo 14 samples. Um, and so we're very anxious when we get back to the Artemis Exploration Zone in the lunar south polar region to look for more fragments of early Earth. It'll tell us what the environment was like. Maybe even we'll find specimens of fossil life sitting there on the lunar surface.

Dr. David Kring [00:43:46]:
So all of those are intriguing opportunities. And, and this is really important. When we go to the Moon, obviously we're going there to better understand the origin and evolution of the Moon, of the Moon. But the Moon is the best witness of what happened to our own planet Earth. And so by going to the Moon, we are also better understanding our own planet Earth.

Dr. Rick Jenet [00:44:10]:
Well, that's, that's very exciting, and, and, uh, it's also great to just hear, uh, more about how lunar science can actually affect our understanding of where our own origins— um, slightly related question, but I'm curious, when you're How much of this excitement do you feel is important that we, that we impart to the astronauts that we're training that are going to be there?

Dr. David Kring [00:44:34]:
Oh yeah, it's utterly fundamental. I mean, it's— in fact, this is, uh, on what I, I trained for many years, the, the astronaut candidates. And when we came up to the impact cratering session, you know, the very first set of slides dealt with all of these issues. You need to understand understand, we would say to them, um, that impact cratering is important for the following reasons. And amongst those, uh, was this period of bombardment. Amongst those was the impact origin of life hypothesis. Amongst those, by the way, is the modern-day hazards of impact cratering processes, right? Um, and, and they have to, um, understand those, uh, deeply, not only because Uh, that enthusiasm, uh, will help them do better science once they're on the lunar surface. They are inevitably in conversation with the public, and the public is going to be answering— asking them those questions.

Dr. David Kring [00:45:36]:
And so they, they have to be experts at some level in, uh, all of the topics that we've been discussing.

Rod Pyle [00:45:45]:
You touched on this for a second, and I don't know if it applies to the Moon or not, but what is the impact origin of life hypothesis?

Dr. David Kring [00:45:53]:
Oh, it is that early in Earth history, when that period of bombardment was occurring, when the largest of those impactors were completely vaporizing seas, making conditions untenable for life at the at the surface, those same impact events were generating these deep subsurface hydrothermal systems below the floors of craters. And that— those environments is where prebiotic chemistry and the early evolution of life occurred. And we've demonstrated with studies at Chicxulub and elsewhere that these hydrothermal systems expand the entire diameter of these craters, that these hydrothermal systems are very long-lived. And in fact, 66 million years ago, my microbial ecosystem actually lived in that hydrothermal system. And in fact, it was the type of community that was thermophilic or hyperthermophilic, that is, it loved hot water systems, which our biological colleagues tell us is the type of community at the roots of the tree of life.

Dr. Rick Jenet [00:47:10]:
And you also mentioned, which I do— I've always found this idea that material travels between different celestial bodies to be quite fascinating. And you did mention, you touched on that there could be specimens or that, you know, we even found some stuff potentially that was Earth-related on the lunar surface. Were you also hinting at that there could potentially be ancient microbial Not necessarily alive, but, you know, evidence for ancient microbes in some of this material that might be sitting on the lunar surface?

Dr. David Kring [00:47:43]:
Well, I would, I would say that there is the potential for finding samples of these hydrothermal rocks and the potential for finding fossilized life. I do have one colleague in the UK that actually suggests that life may have persisted for a short period of time on the lunar surface. Um, but, but that's a lone voice, uh, in, in this, in this discussion.

Dr. Rick Jenet [00:48:13]:
Oh, very neat. And something I, I probably know how you're going to answer it, but I want to just, you know, run this by you because many times, um, we've heard this, right, that, ah, we're not going to send people out into space, we're just going to let robots do it. What are your thoughts on that one?

Dr. David Kring [00:48:29]:
Yeah, humans, particularly if you're going to a complex planetary body like the Moon, humans are essential. And, um, and, and I can say that as a field geologist, I absolutely know what I can do as a field geologist and what a robot can't do. I mean, what I can do and a robot can do are orders of magnitude apart. Now, but you don't have to believe me. So Steve Squires, who was the PI of the 2 Mars rovers, said this himself. He said it multiple times that basically what his rovers were able to do in 6 years, a field geologist could have done in a day. Okay, so just imagine you put 2 astronauts on the lunar surface for 14 days, it would take a robot 14 times 6 years Mm-hmm. To generate the same outcome.

Dr. David Kring [00:49:21]:
And, and so if, if you want to get answers soon, which I think we would, you, you just have to put well-trained, smart-thinking astronauts on the lunar surface. And, and moreover, the astronauts are going to uplift, inspire students and everybody, uh, throughout society. I mean, that's— That is one of the big bangs of Apollo that people sometimes forget. It didn't just inspire scientists like myself. It inspired everybody in the nation because they realized if they put their mind to what they wanted to do, anything is possible. And I hear that, by the way. I give public lectures and people will come up to me and say, I'm a plumber, but man, was I fired up about Apollo. I just every day do my best.

Dr. David Kring [00:50:16]:
Neurosurgeons have told me the same thing. It just had a cross-cutting broad societal impact, and I really hope that Artemis astronauts on lunar surface have that same effect.

Dr. Rick Jenet [00:50:31]:
Now, I guess we only have time for a few more questions here, but, you know, leaning into the human presence on the lunar surface, what's your thoughts about a lunar base? And when we might have one or if we need one?

Dr. David Kring [00:50:43]:
Yeah, I have to say that that's beyond my area of expertise. I know that there are architectural issues related to that and sustainability issues related to that, but I have to simply say that's beyond my area of expertise. I have been asked and can comment on where a base could or should be to minimize hazards to crew. But the rationale for a base is outside of my area of expertise.

Dr. Rick Jenet [00:51:17]:
Okay. And I guess maybe the last thing would be, well, what are your thoughts on where the base should be?

Dr. David Kring [00:51:23]:
Well, you want to— impact events occur and earthquakes occur. And so one of the things you want to avoid are places where boulders might be dislodged and roll into a base. And so that's something that you just have to be mindful of. And so at the moment, that's what we're focusing on. There are other issues to be addressed— ionizing radiation, you know, are there shelters, do you have regolith to sufficiently shield the Moon base, and so on and so forth. But in terms of terrain, you wanna be away from known mapped faults and away from high points, topographic highs with dislodgable boulders.

Rod Pyle [00:52:13]:
So I guess my last 2 points are, first, are mobility systems part of your purview, whether they're human ambulatory or rovers or something else?

Dr. David Kring [00:52:27]:
Yeah, mobility's important. In fact, this is, this is one of my biggest disappointments of the Artemis program. In Constellation, we fed off of the lesson of Apollo, and Apollo taught us that mobility is king. You just have to have it. Constellation was going to land 2 pressurized rovers on the lunar surface before crew landed. And I still think that that's the right answer.

Dr. Rick Jenet [00:52:48]:
Mm-hmm.

Dr. David Kring [00:52:48]:
I'm disappointed that Artemis isn't following that playbook. Um, one of the— we did 4 years of lunar mission simulations in Northern Arizona, testing unpressurized and pressurized rovers and, and how they affected scientific productivity and risk to crew. And, and I can't give you the precise numbers because it's been several years, but it was something on the order of, uh, enhancing scientific productivity by the crew by close to 60%.

Rod Pyle [00:53:18]:
Wow.

Dr. David Kring [00:53:18]:
Also reducing risk to crew by about that same number. So we just need to get the mobility assets on the lunar surface as soon as possible. And pressurized rovers trumped unpressurized rovers every time.

Rod Pyle [00:53:35]:
All right, team Space Show, you heard it. Time to write your senator. My last question here is, can you talk about some of the training opportunities that you and your USRA have created for early career scientists and the international Artemis program partners, a lot of whom are looking for ways to get engaged?

Dr. David Kring [00:53:53]:
Yeah. So we have 2 different types of training programs here. I mean, in addition to that for the astronauts, but for graduate students, we have a program here in Houston where we bring them into Houston We expose them to some of these human exploration elements and ask them to help us evaluate some of these landing sites. The graduate students are the force behind a lot of the landing site and astronaut EVA planning that we've been speaking about. Then it's really important to introduce planetary scientists to field geology. This has been a huge change. When Gene Shoemaker was leading Apollo, every scientist on that team was a field geologist. You had— that was required at that point of time if you were to get a geology degree.

Dr. David Kring [00:54:48]:
I'm old enough, that's how I was trained. But now, many geology departments no longer require field geology, and planetary scientists can go their entire career and never do any field geology. And you have to be expert in field geology if you are going to, uh, help the astronauts work well and work safely and productively on the lunar surface. So we have field programs, field training programs at Meteor Crater and volcanic fields that are lunar analog sites. And, and both of those types of programs have been immensely successful. We've had hundreds of graduate students go through them. We then reach deeper to earlier parts of the career to high schools. We're trying to encourage high school students how to do research, and we've helped another 600 students do research in high schools scattered across the country.

Rod Pyle [00:55:45]:
Over the past few years, we've helped train a little over 1,200 students and it's been Well, before we go, I just want to see if there's anything else you want to discuss, or do you have any books coming up, big papers you'd like to talk about, anything of that nature?

Dr. David Kring [00:56:04]:
Oh no, I just— hopefully everybody, hopefully in your audience has heard the enthusiasm that carries me and the work that the people behind me are doing. doing. Once we get on the lunar surface, it's going to be extraordinary. But, but we have to have well-trained people supporting the crew, and the crew themselves have to be well-trained. And then we have to overcome some of the architectural impediments. We do not have a credible lunar sample return mass capability.

Dr. Rick Jenet [00:56:37]:
Mm-hmm.

Dr. David Kring [00:56:38]:
We don't have credible communication architecture. We don't have mobility architecture as we've already discussed. And those are issues that just have to be addressed. And the faster that they get addressed, the better our work on the lunar surface will be.

Dr. Rick Jenet [00:56:54]:
All right.

Rod Pyle [00:56:55]:
Well, David, I want to thank you. And Rick, I want to thank you and thank our audience for joining us today for episode number 224 that we're calling The Science of Artemis. David, what's the best place for us to keep up to date with your work?

Dr. David Kring [00:57:08]:
I would go to the LPI, USRA LPI website. So type into your browser Lunar and Planetary Institute and you'll have an opportunity to connect to a lot of different opportunities.

Rod Pyle [00:57:23]:
And I would just add, it's worth checking out the USRA, the Universities Space Research Association, and look at their website just at the broader breadth of what they're doing because it's really sensational. Rick, where can we stalk you and your, your work online?

Dr. Rick Jenet [00:57:39]:
Awesome. Uh, have a look at www.expandingfrontiers.org and also nss.org.

Rod Pyle [00:57:46]:
All right, that was brief and compact. And of course, you can always find me at pylebooks.com or at adastramagazine.com or indirectly at nss.org as well. Remember, you can always drop us a line at twis@twit.tv. We welcome your comments, suggestions, ideas, questions, and of course, space jokes, because as you can tell if you're a regular listener, we're always a little shy on those. New episodes of this podcast publish every Friday in your favorite podcatcher, so make sure to subscribe, tell your friends, give us reviews, and like us or love us, we'll take whatever you got. You can also head to our website at twit.tv/twis, and you can follow the TWiT Tech Podcast Network @twit on Twitter and on Facebook @twit.tv on Instagram. Thanks everybody for coming. It's been a real pleasure.

Rod Pyle [00:58:30]:
And we'll see y'all next week.