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 255, Nujoud Merancy discusses the planning and considerations needed to design an Artemis mission to the Moon. This episode was recorded on August 19, 2022.

Transcript

Gary Jordan (Host): Houston, we have a podcast! Welcome to the official podcast of the NASA Johnson Space Center, Episode 255, “Artemis Mission Design.” I’m Gary Jordan, 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. With the Artemis I mission taking the main stage, we hope you’ve had a chance to dig through our collection of episodes leading up to the mission on all the different systems, programs, and of course people that have come together to make this mission a reality. It’s important to note that this mission sets us up for future Artemis missions: next sending humans around the Moon, then landing humans on the lunar surface, then expanding our presence at the orbiting Gateway, new surface exploration technologies, and of course, as always, science. We’re already thinking about what comes next and how these Artemis missions build on one another to continue technology demonstrations, science, and exploration on the Moon, and that prepares us for Mars. To help set the stage for Moon to Mars, there is a dedicated group at NASA’s Johnson Space Center serving as a focal point for collecting as much information as necessary to design Artemis missions. It’s a massive task. So to help us understand the planning and considerations needed to successfully design an Artemis mission, we’re bringing back Nujoud Merancy, chief of NASA’s Exploration Mission Planning office. We get into how and why we’re laying the missions out the way we do. So let’s get right into it. Enjoy.

[Music]

Host:Nujoud Merancy, thank you so much for coming back on Houston We Have a Podcast. Good to have you.

Nujoud Merancy: Thanks for having me, Gary.

Host: All right. One more conversation in the bank. Last time we talked, we talked about Artemis and Apollo. And we sort of did a pretty deep dive because at the time, I think art, this Artemis, the idea of Artemis was really just coming up for the agency and you sort of helped us to set the context because a lot of people were having those questions, right, how, what’s, how does it necessarily compare to Apollo. Why don’t we kind of start there. Just for, for our listeners that maybe didn’t get a chance to do that deep dive, they can go back and listen to it — it was episode 116, if they want to — but just a high-level of what exactly for, for, if you were to catch someone off the street and they say, what is, you know, what’s the difference here, didn’t we already do the Moon, what’s sort of your pitch to them?

Nujoud Merancy: So yeah, thanks. In short, right, it’s a different mission for a different objective, right? So with Apollo, the objective as laid out by President Kennedy was to go to the Moon as soon as possible by, essentially by the end of that decade they were in, and return safely to Earth. So to do Apollo, you picked the easiest place on the Moon to go to, the easiest architecture so a single launch architecture, landing at the equator of the Moon or very near the equator, and coming back with a very short mission, maximum of about 13 days of a mission. With Apol, or with Artemis, what we’re trying to do is really set the stage for long-duration space exploration and explore the South Pole of the Moon, where there’s way more scientific interests with permanently-shadowed regions, way more opportunities to collect science data as well as support long-term technology and habitation development with longer periods of sunlight than the equator. But to do that it’s higher performance, more challenging, lots more effort needed to go into it, as well as smaller budgets because we’re doing it on a sustainable basis not a full-up national priority.

Host: Right.

Nujoud Merancy: So it is really a different mission architected around different objectives. And so there is a difference in what we’re trying to do.

Host: OK. OK. Now the conversation we’re going to get into today is really talking about diving more deep, less so into the Apollo then we did at the last episode, this one’s really going deeper into the mission design for Artemis missions. Now exactly what you’re saying, we’re talking sustainable, we’re talking stuff that’s going to get us to very interesting locations on the Moon. So, and, and then, I kind of wanted to start with like your office, right, you’re mission planning, so you guys are really forward-thinking, you’re thinking years in advance, you’re thinking multiple missions in advance. And it’s a lot of data to gather kind of now, and, and, and to inform what you’re going to be doing years later. So tell me about your group and your office and your efforts that goes into mission planning?

Nujoud Merancy: Yeah. So mission planning, in a very general sense, is the mission engineering, we’re the engineers and it’s largely systems engineering, which means we are integrators of all of the vehicles, the piece parts. So we don’t design the vehicles, but we have to make them all work together and the mission with flight operations, the crew, all the constraints that go into it, to how do you do a mission to meet the objectives. So it’s really an integration function. We have to work throughout: early on we help set the requirements for what you’re going to need, say in a human landing system, how much performance do you need from what orbits, things like that; and then as it goes through development we work with all the teams, the Orion spacecraft, human lander, Gateway, how do you put all those pieces together to get to the spot on the Moon? So it is, it’s a lot of working with the teams, integrating across them, and coming up with solutions in the form of the mission design to meet the objectives.

Host: OK. So you’re pulling on a little bit of the, the engineering design of some of the components of Artemis. You’re pulling on the operations team to learn about how they do operations. And you’re, that’s a lot of data gathering and a lot of stuff to pull, and early, too, right, because there’s, like we’re, we’re, we’re years away from some of this stuff, but you have to do it like now.

Nujoud Merancy: Yeah. It’s very big picture.

Host: Yeah, right.

Nujoud Merancy: So you’ve got to really want to like sort of build the puzzle, right? I have all these pieces, all of us are working our pieces, everyone needs to be successful, and in order for everyone to be successful all the piece parts have to be successful. If anything doesn’t work, if it’s, this is a bad solution for one program, well, that makes the whole thing fall apart. So in a way it’s kind of a great thing because it is really the epitome of getting everyone to work together…

Host: Right.

Nujoud Merancy:…but it is also a big challenge because you’re working essentially with the world’s biggest LEGOS of how do we put these things together.

Host: [Laughter] That’s really a good analogy. I know, like I was a big LEGO guy and, and when I was, when I was a kid, I totally get that. Now in terms of the, the idea of bringing all these pieces together and, and thinking about you, you talk about like defining requirements and that sort of thing, in terms of mission planning, we’re still kind of at this like bird’s eye view right now, in terms of mission planning, how, how solid do you guys try to make it and how do you factor in just natural changes over time as you learn more information, as things become developed, as you get a better idea about, you know, production and manufacturing schedules and this sort of thing, how do you, how do you come up with an idea early but then have it be malleable enough to meet everybody else’s mission objectives?

Nujoud Merancy: Yeah. I mean, that’s a big part of what the team has to do. It’s, actually it’s an iterative process, right? We think it’ll work this way, but as the vehicle design develops or we get more data and we study, right, we have to plan for all the contingencies too. So as you peel back the onion layers you always find another layer underneath. So you just keep going and going and iterate on it. So things like Artemis I, which we’re about to launch, originally we planned a 26-day fixed mission. It was only going to be one length, but as we started doing mission design and working with the programs we found we wanted to land during daylight to collect parachute data on Orion. So in order to do that we had to make it a variable mission length. So that’s why we have a 26-to-43-day mission, depending on the day we launch. So it’s that sort of changes that occur through the mission design to meet the objectives a program needs. So it’s just a really clear example of, really we’ll change the length of the mission so we can target that landing at daylight, and that’s exactly how that sort of iteration goes.

Host: Got it. OK. Yeah. And we will spend some time specifically on Artemis I just because we’re, you know, it’s happening, you know? Like, you’re like, we’re, it’s like, it’s like very around the corner. But then of course, you know, Artemis II, III, I mean this, like that part of your, your office is really thinking far ahead. Let’s keep up here with, with mission design and just some of the, really what I want to get into is just some of the considerations. Get a full understanding, because you’re talking about pulling all the different LEGO pieces together to build this beautiful LEGO sculpture, right, you’re, you’re, you’re pulling all of these pieces. Want to get an understanding of some of those pieces, right? And I think one, one of that comes naturally to, to mind for me is the manufacturing of certain things. We’ve had a lot of different program representatives on, they talk about Orion and there’s multiple Orions and iterations of Orion that are in certain readiness of manufacturing. Of course, SLS and the Space Launch System has its own manufacturing, but then these different block builds that change over time, right? You have ground systems, you have the Gateway, you know, all these programs they’re building and they’re, they’re doing all these things on their schedules. How do you learn all, all about that, and then factor that into these future missions and, and the ready, having an understanding of basically when things are going to be ready?

Nujoud Merancy: Yeah. So a lot of it starts with what’s the objective of the mission, and then you sort of decompose and assign the pieces to each vehicle, right? SLS and Orion are just get the crew safely to and from lunar orbit. The lunar orbit, we have agreed, it’s an agreement essentially between all the parties — Gateway, Orion, HLS (human landing system) — which orbit we go to so they can meet up and you know, they literally dock and come together there and transfer the crew. So you have to start at that, right: what does it require, what’s each program’s part to play and then they do their work to analyze to it, and any issues that come up come back to us and we help, you know, solve them, right? We’ll look across all the programs and find a solution that works for everyone and can be done on the timetable. But yes, as you mentioned, right, there are upgrades that’s going to change. One mission doesn’t look like the previous mission, and we get to keep building. So that’s part of being sustainable is to be able to keep incorporating new things, new systems along the way. So, right, we had Orion, Gateway, HLS, now we have our first human landing system in Starship. So how do we work with Starship to complete that part of the mission? So yeah, the goal is to keep being flexible and incorporate these things as they come in. A lot of times it’ll be upgrades in performance, like SLS going from Block 1 to Block 1B when it gets a bigger upper stage. So yeah, it’s a really fun puzzle that keeps growing and growing and we get more and more performance along the way.

Host: You got to love that stuff to really, to really go into it, right? You got to love the planning, you got to love, all right, like it’s almost, I feel like there’s an aspect of creativity to it too. Like how, like here’s these new and interesting problems we like, and here’s a, here’s how we think is the best way to solve it. You just got, you got to have the right people that love that kind of stuff to really…

Nujoud Merancy: And I think it’s really underappreciated, right?

Host: Yeah. Yeah.

Nujoud Merancy: Everyone thinks of engineering as math and numbers and very hardcore things, but we got to be super-creative…

Host: Yes.

Nujoud Merancy:…like what’s a better way to solve this problem? And it’s not always what’s the best technical answer, but what can we actually afford, get done on schedule, analyze and verify? I mean, it’s the engineering piece is a part of it but some of that is the creativity of what is a good way to solve this problem.

Host: There’s, so another one you mentioned in terms of the, the considerations that you’re pulling in to make, to design some of these missions, you talked about orbits. You’re like, depending on what orbit we go into, and I know it changes over time when we’re thinking about Artemis missions, right? So Artemis I, we talk about DRO (distant retrograde orbit) quite a bit, right? And then as we get into a sustainability of, of, of Artemis missions, NRHO (near-rectilinear halo orbit) comes, comes into consideration. You talked about Artemis I having this wide range of 20-something days to 40-something days, right? Let’s, let’s do a little bit of, of a dive into orbital mechanics and just sort of understand…I mean, or, Orbital Mechanics 101. What’s happening that creates these wide stretches of time, 20-something to 40-something days? What are the different orbits? Let’s, let’s do a little bit of a dive into orbital mechanics.

Nujoud Merancy: Yeah. So orbital mechanics and the sort of the architecture is the trajectories are what underpins all that mission design. So for Artemis I, you said DRO: for the listeners, that’s a distant retrograde orbit. It’s called that because it’s very far from the Moon, very high altitude, so about 40,000 miles from the surface of the Moon in a sort of ellipsoid, and it’s retrograde because it’s rotating the opposite direction the Moon is going. So just sort of backwards if you look at the way the Moon is. So that orbit we’re used, it’s in the Earth- Moon plane, means it’s flat, it’s around the Moon’s equator, and it’s used because it’s a very stable orbit. So if you want to park something there, you don’t need a lot of pro — you don’t need any propulsion capability — to stay there, but it’s a really good test orbit. It came up early in designs of lunar architectures, and so that’s why we’re using it for Artemis I. And it’s also very good at what we need, which is that variable duration. We, we, because we were in the DRO, we found that it could be used to do this duration change to get what we wanted for Earth entry conditions. So, yeah, so this orbit is a really good stable orbit, meets all of the objectives to test Orion in deep space. But whereas when we move to Artemis II we’re actually not going to go into a lunar orbit: we’re first going to do a high Earth orbit followed by a lunar free return flyby. So that allows us to check out Orion with the crew systems around Earth; very safe, we can abort much quicker from it. And then if everything’s good, though, we’ll proceed to let the crew do a lunar flyby and we actually use the Moon’s gravity to slingshot back to Earth. So Artemis II was very much designed at that trajectory, that mission design, about what is the best way to do a crewed test flight. And then when we get to Artemis III and we want to land on the Moon, we go into a near-rectilinear halo orbit. So those are a lot of big words for a very large ellipsoid orbit that actually is out of plane. So rectilinear, it’s about 90 degrees out of plane from Earth-Moon. So it goes down below the Moon, around below the South Pole, and that orbit is also a stable orbit but it provides that South Pole access. So very key there because on Artemis I, we’re not landing on the Moon.

Host: Right.

Nujoud Merancy: So we didn’t need to change the plane of the orbit. For Artemis III and beyond we want to go to the South Pole, so we’re doing that orbit that orbits north-south, essentially, over the Moon.

Host: Yeah. OK. Yeah. The, the DRO and the flyby, they don’t get you to the South Pole. So, so really that’s one of the big considerations for NRHO is you want, you want that South Pole access?

Nujoud Merancy: Yeah. So that South Pole access for Gateway, long-term stability to build out a, a habitat, a cislunar habitat outpost around the Moon, and the lunar access to get down to the surface on the South Pole. So there’s sort of a balance of objectives in how we selected the NRHO orbit.

Host: OK. And for Artemis I to, to, to complete the story on the DRO, distant retrograde, the reason for the, for the variation in the potential times is really, is it really just how many laps around that DRO you, you because you said it’s pretty stable orbit, it’s really just about laps?

Nujoud Merancy: It is. So on the shorter missions we’ll stay there for half an orbit. It’s a, it’s a 12-day orbit period, so it takes 12 days to go just once around the orbit. So for a shorter mission we only spend six days or so in the orbit.

Host: OK.

Nujoud Merancy: When it’s a longer mission we go one and a half times around the Moon, so you spend about 16 days in that orbit.

Host: Yeah. OK. All right. So, now we’re zooming ahead, right, we’re just, we’re talking about Artemis missions and just some of the considerations, obviously you alluded to NRHO giving you access to the South Pole to land on it, obviously, landing sites are one of those things. And actually, I think at this very moment you and I are talking, I’m sorry…

Nujoud Merancy: I just left the press conference, I was listening to it before I came over.

Host:[Laughter]…I was saying, I feel so bad because there was just, just the way that things happen, but they are talking about the landing sites right now…

Nujoud Merancy: Yes.

Host:…as, as we speak. And that’s very exciting. So, so those are things that you have to consider. It, the way that NRHO kind of interacts with the landing sites, is there, is there any considerations there, like maybe time of day and, and shadows of, of the Sun or like, what are the considerations for actually landing in these South Pole regions of the Moon?

Nujoud Merancy: Yes. The, how we land on the South Pole is going to be very challenging. It’s a lot of opportunity, but that also makes it very challenging, right? So when you’re on the South Pole or any, either North or South Pole of the Moon, the Sun is very oblique, meaning it’s very low on the horizon. It’s never more than six degrees above the horizon. So if you know, you look at sunset and the Sun is just above the, the horizon that you’re looking at, that’s what it’ll look like all the time on the South Pole. But because of that, the Moon can be, or the Sun can drop just below the horizon of the Moon and just above it a lot. So we end up with periods where you could have days of sunlight in a row on one spot, but then you’ll have shadows for days at a time. So we’ve got to time our landing on the South Pole so that we land in the very particular spot that will have Sun for at least six days because our surface missions will be about six days long. So there’s a whole lot of analysis. There’s a really big team across the agency and including the vendors out there and the scientists that look at these, the data of the terrain, the Sun, the conditions, are there boulders, to pick where is a good opportunity to land, and then we have to time that with when Orion and Starship will meet for Artemis III in orbit. And there’s a weekly period, it’s a seven-day period in that NRHO, so we have to time all of that, and then pick a landing site when HLS can make the descent to a spot that has sunlight on it.

Host: Ah. So how do you, if you’re talking about, so one of the things that, just in regular human spaceflight, right, this happens literally all the time is, just, you don’t always get off the pad when you want to get off the pad. You know, you always have weather considerations, right? There’s, even for Artemis, we’re looking at these launch periods and then each of these has to come with its own analysis. When you start factoring in stuff like that, right, so when, if you’re, if you’re in a launch period, if you’re in a launch window, and you are going to land on the surface of the Moon, does the, does your landing site change as launch opportunities change because of lighting?

Nujoud Merancy: It can.

Host: Interesting.

Nujoud Merancy: So yeah. So we’re still working through how exactly we want to set up the conditions. So we’re looking at how much variability do we have in the vehicle performance, can we tweak the orbit here or there, how many sites do we need? We hope, I mean, it would be a lot easier if we can get down to just one site.

Host: Right.

Nujoud Merancy: But because one site isn’t available all year long with sunlight, you have to then start, you know, figuring how many sites do I need to look at, or can I slightly adjust the orbit to get to a different site? So we’re working through all of that right now. And yes, the goal is to have lots of launch opportunities because you always have, you’re getting a very complex rocket off the ground, whether it’s Starship or SLS, they need to get through all the weather conditions, right, if there’s a storm. So the more opportunities we can give, the more likely we have success. So planning for those landing sites, we then have to work backwards to make sure that we can launch the rocket and give ourselves a lot of probability of success in doing so.

Host: Got it. OK. Now another consideration I wanted to talk about was the, a lot of the engineering considerations, right? So Orion’s, can, you know, Orion’s solar power and like battery considerations, ECLSS (Environmental Control and Life Support System), right, how long they can support life, and so, so, a lot of these, a lot of these different engineering considerations for how, how these spacecrafts, how these things will work in orbit; how are you taking some of these considerations and building them into, you know, for example, you talked about the surface operations being like six days, right, so you have to, there’s, there’s certain things that you have to consider to, to make that happen. Orion’s going to be in orbit that time. What are some of the engineering considerations that you’re putting in?

Nujoud Merancy: Yes. At a very fundamental level, right, you know, you only have so much stuff that you can bring with you. So we have certain size oxygen tanks, water tanks, food onboard. So yeah, the mission design then has to account for, I only have so many days I can let the crew travel to the Moon, so many days will spend in orbit, so many days HLS could be on the surface with their food and water system. So yeah, so we have to work through all of that. There’s a partnership: that’s part of the big integration challenge, right, is does this vehicle have enough commodities on it, can you share commodities? Say, say one vehicle has extra food; well, we’ll make sure we use that in the planning so that we don’t have to carry stuff we don’t need. It’s very hard to go to the Moon, so we need to account for everything, make sure we’re not leaving any gaps, but also make sure we’re not taking stuff we don’t need, and because that could free up space for say a science payload. So, right, there’s a lot of integration that’s going on: how many days do we spend where, how much food, the engineering systems, and then of course planning for all the contingencies, just in case anything goes wrong along the way.

Host: That’s a huge one, right? So in terms of your planning, you, you mentioned this right up, right up the top, that was like one of the first things that you mentioned was, it’s, you’re already explaining how hard it is just from just like a normal, normal planning. [Laughter]

Nujoud Merancy: The nominal mission is hard enough.

Host: [Laughter] Right.

Nujoud Merancy: And then you add the contingencies.

Host: Exactly. Right? So like Orion, for example, Orion’s built to sustain, you know, just in case something were to go wrong, it’s got like a lot of these redundancies built in for exactly that, for contingencies. You got contingencies where astronauts can go into the suit for a couple of days. How do you build that into like, not only are you designing a mission and you have to be flexible depending on, you know, which day you launch and you have to do the lighting considerations, but now you have to think, OK, if something were to go wrong at this spot, what do we do if we were to go this spot? Are you thinking about that too?

Nujoud Merancy: Yes. Absolutely, right? It takes days to get home from the Moon. So you can’t just say, OK, well I quit if something goes wrong and we’ll be home in an hour, right? It’s days. So everything needs to be planned, and this is where communication, right, it takes a big team, all the teams doing this communicating and working with each other, because we have to rely on each other’s support, whether you’re on HLS or Orion or SLS to, to work through this. And that’s where, you know, that’s the other thing, engineering’s all about communication. And “how do we solve this problem?” takes everyone talking to each other and sorting through the problems.

Host: Very important, very important. All right. One more consideration that I at least have written down and then we can explore other ones that I might be, be forgetting, are of course, the people, the astronauts, right? Of course, we talked about the environmental control and life support systems as being one of the things you have to, you have to factor in, it’s just the, it’s the Orion ECLSS is designed to support humans for, I think, three weeks, right?

Nujoud Merancy: Yeah. Four crew for 21 days

Host: Four crew for 21 days, right, so that’s a, that’s a big consideration there. The radiation limit, right: now we’re leaving low Earth orbit, now, now people are entering into the, the Moon; are there any considerations for how, how long they can be there, what are their radiation limits that you have to plan for, for, you know, would we even come close to that three weeks when it comes to radiation limits?

Nujoud Merancy: So, you know, radiation is a big factor. When you leave low Earth orbit, you’re still protected by the atmosphere and the magnetosphere when you’re in low Earth orbit. So if you’re on ISS for six months, you’re getting a certain amount of radiation dose. When we start planning missions out to the Moon, a few weeks is equivalent to that six months on ISS. So yes, the human factors team have to do a lot of consideration about radiation, but we also have to just sort of factor it into what’s acceptable dosage, because if we want to explore the Moon and you want to do it well, we need to go and we need to be there for a significant amount of time. So then you need radiation shelters too, because one of the important things is there’s so much radiation. You get a sort of background radiation just for being at the Moon, but if there’s a solar particle event, which is a big solar storm, and lets off a burst of radiation, how do you protect the crew? So all of the vehicles will have radiation shelters, plans, and things like that, and it’s really how do you pack a lot of stuff around the crew to block that radiation. So, yeah, so you have to sort of plan for these things because the solar particle event, if you’re out at the Moon, is a significant dose all at once. So you have to have shelters for those, and then the medical teams have to account for just sort of that background dose you get just for being outside the magnetosphere.

Host: OK. So it’s, it sounds like it’s more of like, more of the engineering design of some of these different vehicles that is really probably one of the drivers of radiation protection, more so than actually planning a mission around certain things, right?

Nujoud Merancy: Right.

Host: OK.

Nujoud Merancy: We’ll, we’ll have to fly through what are called the Van Allen radiation belts to get to the Moon.

Host: Right.

Nujoud Merancy: You just do the math for the accounting on how much exposure that is. The medical teams factor that in for all of the crew members, you know, lifetime considerations will come into effect. You don’t want, you can’t send the same person out there a hundred times because they start to accumulate a lot of radiation. But in this case there’s a lot of engineering going into radiation shelters for those, really, on, one-off events if they occur.

Host: Right. Right. And you know, there’s a certain amount of prediction I think when it comes to those that you can have insight into, but then there’s, there’s a lot of times where it just, you know, just sort of happens, right?

Nujoud Merancy: Yeah. They, they’re essentially random.

Host: Yeah.

Nujoud Merancy: There’s a, there’s some probability it’ll occur in any given day, but you don’t know when that would be.

Host: Right. Exactly. Exactly. All right. Other considerations that maybe I’m forgetting that is probably more prominent in your life that maybe folks like me just don’t normally think about when it comes to trying to put a mission plan together.

Nujoud Merancy: I mean, I think one of the things to keep in mind is it’s a, it’s a three-body problem. The Earth, Moon, the spacecraft are all gravity interacting with each other. Things like the distant retrograde orbit and near-rectilinear halo orbit, they’re actually under the influence of both Earth and Moon gravity at the same time, so you’re sort of balancing, you’re sort of surfing the gravitational waves in those orbits. But then we also have to plan for the Sun. And so you mentioned solar arrays and stuff and eclipsing, so we, you know, the, the trajectory experts are actually doing math with, you know, four big bodies all at the same time: everything’s moving, the Earth’s rotating around the Sun, the Moon’s rotating around the Earth, the spacecraft is rotating around the Moon. So all of that’s going on and we have, so there’s a lot of calculation behind it to keep all of the, keep track of where everything is.

Host: OK. So, OK. Here’s, here’s like an instance that maybe comes to mind, you tell me if this is actually like a, like maybe an issue or maybe it’s a non-issue. Is like, for example, like you’re saying these three bodies…a lunar eclipse: like would, would you be able to fly a mission during a lunar eclipse because maybe you wouldn’t get this, the solar power that’s required? Is that like something that you have to plan around?

Nujoud Merancy: That is absolutely something we have to plan around. And that’s actually one of the drivers for the orbit we picked…

Host: Really.

Nujoud Merancy:…the near-rectilinear halo orbit. So one of the special things about the orbit and, in very particular, the particular size orbit we picked was because it’s called a 9:2 resonance: so for every two lunar months, it makes nine orbits. That’s where the six and a half days comes from. But in that resonance we always pass below the shadow of the Earth, because being out near the Moon’s distance, that Earth shadow is big. It’s about three to four hours if we were to fly through the Earth’s shadow, which is very hard on your power systems and thermal systems. So by picking that particular orbit for our architecture, Gateway, Orion, the Starship, whenever they’re in NRHO, we’ll only have very short eclipses of just the Moon. So we can, we sit, we essentially picked an architecture that plans around Earth eclipsing, and a lunar eclipse, essentially, that could follow on the same time.

Host: Wow. Yeah. NRHO is looking pretty good the more that we talk about it, right? It’s, you said it’s, it’s easier to sustain with limited amounts of prop[ellant], it gets you that South Pole access, and you have to, you, you have a little bit more flexibility when working around difficult lighting situations.

Nujoud Merancy: Right. We make the vehicle design easier because we can work the power and thermal problem and avoid extremely long eclipsing. So yeah, there’s a lot, all those design factors went into this architecture early on.

Host: Interesting. OK. All right, cool. Yeah. I love this. I love this. Yeah, we’ll, we’ll when we we’re, we’re next going to dive into a couple of the Artemis missions, just to sort of better understand maybe at a deeper level, each of these, each of these considerations that we were talking about and maybe we’ll reveal more of the considerations as, as we go through them. Let’s, of course, start with Artemis I. So for those that are maybe like really want to tune into the Artemis I mission and really understand what’s happening, can you give our listeners a, an understanding of exactly what, what, what is the mission design from launch to splashdown, talking about distant retrograde orbit? What is, you know, like why, why is this mission designed the way that that is?

Nujoud Merancy: Yeah. So Artemis I is an uncrewed test flight. So fundamentally in the mission design, we wanted to make sure we demonstrated all of the vehicle systems in their planned long-term environment. So for Orion that means deep space conditions, SLS the whole launch sequence, and for our ground support systems that countdown and the recovery of Orion. So fundamentally, how do we make sure everything gets tested on this flight? The more data, the better, so a longer mission the better. We don’t have crew on board so this is kind of a chance where you can stress things out a little bit and not be risking human lives. So we’re going to launch from the Kennedy Space Center. SLS will take off with Orion on top. It’s about an eight-minute ride uphill and then the core stage and the SRBs (solid rocket booster) will have done their job, they’ll have separated, and the interim cryogenic propulsion stage will coast with Orion to apogee, which is the highest part of the Earth orbit. It performs a burn to raise perigee; Orion will be all checked out during this time, make sure everything’s good. And then it’ll perform a trans-lunar injection, so ICPS will perform the big burn that sends Orion to the Moon. All of that will occur in less than two hours from launch. So a lot of stuff happens right up front. And then after that Orion’s on its way to the Moon and will spend about a week on its way to the Moon, and then perform a flyby of the Moon. And we use that flyby of the Moon, we’re using the lunar gravity to slingshot up into the distant retrograde orbit, and then Orion will do a burn to stabilize in that orbit and then continue checking out systems. So there, when we get a, you know, very stable orbit, we’ve been checking out systems the whole way outbound. The team will continue to check out systems in the orbit. If everything looks good, Orion will perform the burn to leave orbit, fly back by the Moon and use the Moon’s gravity to reverse the process and slingshot Orion back towards Earth. So again, Orion will spend about a week headed home and perform a direct entry. So this is when things get really exciting. At about 400,000 feet altitude above Earth, Orion will be going about 25,000 miles per hour. So this is one of the major objectives is testing that heat shield on Orion. This is all the system checkout, right, from beginning to end, we get to test the heat shield, the largest heat shield flown for a human spacecraft, and verify that that, and all of the parachutes, work and splash down in the Pacific Ocean, very gently, right by San Diego, where the Navy ships will be waiting to pick up Orion. So all of this is designed to test the systems needed, so we can say the rocket, the spacecraft, everything’s good for crew.

Host: Got it. OK. Yes, we are, yeah, we want to make sure that this is good to go. The first thing one, one of the first things you mentioned when you were talking about it was putting stress on the vehicle to really test it out, right? Now, when it comes to, when, when you were approached to say, hey, we want to make a design, that’s going to fulfill all these objectives and we really want to push this spacecraft to the limit, right, what exactly is, what exactly is being pushed here, what exactly is being tested, and you know, to, to maybe some of the higher limits than you would normally kind of think about for, for a crewed mission, what exactly is happening to really make sure this, this guy’s good to go?

Nujoud Merancy:Well, I mean, it’s really kind of the first for all of it, so any, the first time you do anything, but also, right, a 43-day mission, the first time you fly Orion, we wouldn’t do that with crew, if this were the very first time, with crew, right?

Host: Right.

Nujoud Merancy:But, you know, we need the full, it’s not so much that you’re pushing it above its design limit, but we’re at the design limits for all these things.

Host: Got it.

Nujoud Merancy: The reentry. We’re using most of the prop in Orion, we want to make sure that all the systems get demonstrated. So really, you’re testing everything, the batteries, and it’s not that we’re stressing it beyond design, but we are using the systems as designed and demonstrating that they’ll work.

Host: OK. Using the systems as designed to get it to, as you mentioned, that, this is the perfect phrase, design limit, is just, you want to like, this is as far as we think that these systems will go and let’s, let’s see, let’s see if it actually does it, right?

Nujoud Merancy: If we, you know, we’re doing everything at only 50%, how would you have the confidence for the crew? So we’re really doing everything exactly as we think it should work, so that we have the confidence it will.

Host: Got it. OK. Now you, the, when you, when fast forwarding to the exciting part, when you were talking about the exciting part of, of the direct entry of, of Orion. Now, this one, I know there was, for example, going way back to — 2015? — EFT-1.

Nujoud Merancy: December 2014.

Host: December 2014, OK, thank you for correcting me. EFT-1. Now that one, of course, tested the heat shield. It did not go all the way to the Moon, right? Is there a, is there a benefit of testing the heat shield by this particular trajectory?

Nujoud Merancy: Yeah. So when we did Exploration Flight Test 1 it, we launched on a Delta IV Heavy, which is a much smaller rocket than SLS. And we pushed that rocket as to its limit, and it got Orion as high as it could, but it reentered it around 20,000 miles per hour. So, but heating and all of the, you know, effects of aerodynamics are exponential. So that last 5,000 miles per hour is actually very important. But it’s also very hard to test heat shields on the ground because you need very expensive arc jet facilities, and they can only do coupons that are like a couple inches in size. Orion has a five-meter heat shield.

Host: Yeah.

Nujoud Merancy: So being able to do that full-size heat shield, all of the data needed, in the flight environment, at the speeds it needs to be going, it’s truly something you can only fully test in flight. So we have a lot of confidence in the heat shield design, but we really need that lunar entry speed and all of the associated things to finish collecting the data. And there’s a lot of sensors embedded in the heat shield. I mean, there’s a ton of sensors all over SLS and Orion for the purpose of collecting data, to validate that all of the designs and the models and the work on the ground is correct.

Host: Of course. Now, of course, that’s, that data is going to be very precious to a lot of people. Is it also precious to you? Are you going to, is anything on Artemis I going to affect any of the mission designs, planning, anything that you for, for your group, for Artemis II and beyond?

Nujoud Merancy: Oh, absolutely. So really, and it’s leaning on the vehicle programs themselves, so SLS and Orion, you know, we, we have math models; they have uncertainties, right? So you may have some mar, we have margins on everything. So once you get flight data, you can start to refine like, oh, this worked better than we thought, and things like that. So they can start to remove some margins, which could provide benefits downstream. And, you know, once you’ve flown things, you know, no one’s ever flown a spacecraft and not found something interesting, right? Whether it’s ISS or shuttle or Soyuz, you know, everything has been flown and there’s something you find you learn when you do it. So we absolutely need to fly it, understand any characteristics of that flight, and it will affect our mission designs downstream.

Host: Got it. All right. Let’s go to Artemis II now. Now this one, of course you mentioned, you, like right off the bat for Artemis I, really long mission, you really want to test, you’re testing the systems, you’re testing the vehicle. Now you have the human consideration: a lot shorter. What, what’s the design? How did you, how did you figure out the design of Artemis II?

Nujoud Merancy: Yeah. So Artemis II is very different than anything, doesn’t look like any other mission that’s been flown. And the point of Artemis II, being the first time we fly crew, is testing out those life support systems, the exercise, just the procedures of the crew being in the vehicle. So this is a 10-day mission, but very different: instead of going to the Moon on the first day, right — ICPS, SLS and ICPS will sort of do the same thing they do on Artemis I, but they’ll only put Orion in this high-Earth orbit. So it’ll be in a orbit, it’s, it’s an ellipse around the Earth, it’s about 70,000 [kilometers] at apogee. So the highest point, it’s still, it’s very high above the Earth, but not near the Moon.

Host: OK.

Nujoud Merancy: And it’s a 24-hour orbit. So one day to go once around the Earth in it. But that orbit will allow us a day’s worth of checkout time on all the life support systems, the exercise, you know, the first time the waste management system is flown, all those things will be checked out in Earth orbit. If for any reason something’s not going right, then we can abort back to Earth in a relatively short period of time.

Host: Oh, OK.

Nujoud Merancy: But if everything goes as expected, and we have a lot of confidence in that, Orion will complete that trans-lunar injection burn and send Orion and the crew out to fly by the Moon. So it’ll be much closer to Apollo 8, but we won’t enter lunar orbit. We just use the Moon’s gravity to slingshot back around.

Host: OK. OK. So I, I totally get the, the, the high-Earth orbit, or the Earth orbit part. You want to make sure everything’s good before you commit to going to the Moon. Now, if you’re testing out a lot of the systems in Earth orbit, what’s the benefit of going around the Moon? What, what’s the added benefit of the test by sending humans out there?

Nujoud Merancy: Well, then we’re starting to collect data with time, right? So we can send them to the Moon, now you’re checking it out in the cislunar environment, and you know, any engineering data, the more you can collect the better. So that’s why we, we call this a hybrid flyby because it’s a hybrid of an Earth mission and a Moon mission all in one. So the advantage is really that, you know, we do get to go to the Moon with humans for the first time in over 50 years.

Host: Oh, yeah.

Nujoud Merancy: Can’t underestimate how exciting that’s going to be, but right, it is a hybrid mission where we’ve sort of combined the two of an Earth and a Moon mission to collect a broader suite of data.

Host: Yeah. OK. All right. So now Artemis II, you’re getting a lot of data about humans in the lunar environment. You’re getting a lot more confidence in the systems that are going to sustain humans in that environment. All of a sudden you jump into Artemis III. Now, there’s a lot that goes into that. So let’s, let’s talk Artemis III.

Nujoud Merancy: Yeah. So Artemis III, and actually I want to step back one, right…

Host: Oh, sure.

Nujoud Merancy:…before Artemis III, the Human Landing System will have an uncrewed demo[nstration] demonstrating their systems landing on the Moon. So as we talk about building up systems, right, SLS and Orion will have a demonstration, HLS will have their uncrewed demonstration, and then we get to Artemis III, and we put it all together.

Host: Got it.

Nujoud Merancy: Right. So Artemis III, SLS and Orion, will launch. And at this point HLS will be waiting in, NRHO orbit. So it’ll be waiting, it’ll have launched first, it’ll be fueled up and ready to go, we know it’ll be solid and the systems checked out, and then we launch the crew to meet it. They’ll meet in that near-rectilinear halo orbit. They spend just a couple days together getting HLS prepared for the surface, and then two crew will descend to the surface and two will stay in Orion. So kind of a split crew system, similar to what Apollo did. In this case, two crew will then land on the surface, they’ll have about a six-day stay on the surface performing that first EVA (extravehicular activity). So also, another system coming online for Artemis III are the spacesuits.

Host: Yep.

Nujoud Merancy: So the first exploration spacesuits will be onboard. The crew will do the science, collect data; we’ll know how, how HLS works, how the spacesuits work. And then after the six days they’ll return to NRHO, redock with Orion, put the crew all back together, and then Orion will bring the crew safely home again. So it’ll be a very exciting mission…

Host: Yeah.

Nujoud Merancy:…obviously, a lot of firsts on that one again, too, but a lot of the testing that leads up to it as well.

Host: OK. All right, let’s, let’s dive into some of the interesting parts about that. Particularly, let’s start with the lander, right? So you talked about, you’re going to rendezvous with the lander in NRHO and then do a couple of days of checkouts. That’s, that’s a decent amount of time for, for checking out what, what exactly is the crew doing to get it ready for landing?

Nujoud Merancy: Well, there’s actually a lot in the orbit mechanics, right?

Host: Oh, interesting.

Nujoud Merancy: Orion arrives to meet in our, HLS at a certain part of the orbit, and we have about three to five days, or three to four days, before it’s the point at which it’s efficient for HLS to go down to the surface. So part of it’s the orbit mechanics, but part of it also is that crews have to dock and you have to open the hatches.

Host: Yeah.

Nujoud Merancy: You have to go in HLS in space, you have to get the spacesuits prepared for the spacewalks and stuff. So their crew will actually have very full days doing all of the system checkouts and the spacesuit work they need to, to prepare for that surface mission.

Host: Ah, OK.

Nujoud Merancy: So the crew will be very busy in those few days we, they have, but it’s also the benefit of orbit mechanics is we have those few days before HLS descends to the surface.

Host: Got it. OK. What are the drivers behind the six-day lunar excursion, right, because of course, when you, when Neil [Armstrong] and Buzz [Aldrin] landed it was just a couple of hours, right, but now we’re talking about first time, right off the bat for the Artemis mission, it’s like a week, right? So what, what are they doing?

Nujoud Merancy: The driver is the duration of the orbit. So, HLS goes down to the surface, Orion is completing the lap around the Moon, essentially, and then at the optimal time, HLS takes back off again and meets Orion.

Host: OK.

Nujoud Merancy: So the driver is this combination of the orbit mechanics and where Orion is in the orbit when HLS comes back up.

Host: Got it.

Nujoud Merancy: You know, long term plans are to get to 30-day missions on the surface of the Moon. So at this point a week at a time is biting it off in a smaller chunk.

Host: [Laughter] So there’s OK. So that the orbit makes a lot of sense, but then of course that’s going to have to be one of the big considerations for the design of HLS and, and, the spacesuits is it’s got to have enough solar power, enough food, enough battery power for the suits and all of this stuff to really make sure that astronauts can have a, have a decent, very productive six days.

Nujoud Merancy: Right. And when we talk about contingencies we’re already working out these things, planning for it. There are times HLS can leave the surface and get back to Orion at non-optimal times, as well as sometimes it might be easier to just stay on the surface, right? If a spacesuit breaks, well, OK, just stay in the capsule, right? So, you know, the combination of how you deal with different contingencies, so we are working through that, you know, having spare commodities on board, oxygen and water, or, you know, what is your decision about how you respond to any given situation that might occur.

Host: OK. So built into it is, automatically, we’re not just thinking six days, we’re thinking, you’re thinking contingencies, right? So you got to make sure you’re prepared for well beyond six days just in case.

Nujoud Merancy: Right. Right. If, if for some reason there’s a problem with that landing, they can just take back off and meet Orion, right? You know, those types of things are already in work, what are the options in there as well.

Host: OK. Wow. This is awesome. Now, now this is such an interesting program, Artemis, a lot of, a lot of, a lot of work’s being put into it, there’s a lot of infrastructure being put into, like, just really everywhere around the United States to supporting Artemis missions going beyond. And I feel like, particularly for you, you know, one of the things we’re thinking about is just, you know, why we’re doing this is, is Artemis, there’s a lot of, there’s a lot of interesting scientific things that we can discover on the Moon, I think, like I’ve talked to the, the geologists, the lunar geologists, man are they really excited to get some of the…

Nujoud Merancy: Oh, they’re so excited.

Host: [Laughter] That’s, it’s unbelievable talking to them. They’ve like, they’re, we’ve been using the same samples for, from Apollo for a while, and now it’s like, oh, we’re going to get some good stuff, we’re going to get some stuff from the South Pole.

Nujoud Merancy: Yeah, it’s very exciting. I mean, there’s only like 800-ish pounds of material that’s been brought back from the Moon, which is not very much in the grand scheme of things.

Host: Exactly. And I mean, they do have it from interesting locations, but this is just going to be a lot and this, but this is really, I think what’s really cool about this is there’s so much engineering that’s going into the design of a lot of these components, right, we’re already talking about Orion, we’re talking about SLS, we need to circle back on Gateway, we, I think we need to talk about that a little bit, but there’s so much that’s going to inform us about Mars, right, because you’ve already, one of the things I think you’ve mentioned right up top, Nujoud, was, like, the Moon is hard. Talk about, like, and we, I hope for our listeners this is becoming abundantly clear: it’s just like, there’s a lot of challenges that just go with the Moon. And all of the different considerations for lighting and this, that, and the other thing; Mars is just so much harder, right? So it’s like, I think it’s, to me, and, and I do want to hear like your perspective on this, the Moon does such a good job of preparing for Mars, testing all these different systems, getting the operations down of all these different, you know, bodies and, and in the solar system. From your perspective, from a mission perspective or mission planning perspective of all of that, do you feel the same way, that Artemis does a good job of preparing for Mars?

Nujoud Merancy: Absolutely. So preparing for Mars, right, just to characterize it, right: if you’re in low-Earth orbit at the space station, you’re a few hours from home; when we go to the Moon, we’re days from home; and when you go to Mars, you’re months from home. So just scale the challenge with those durations of time, and that’s the challenge in mission planning. So being able to build our flight systems that can be good at the Moon and good for contingencies that are days long, a week long, right, that’s just the next small step towards what we need, are vehicles that are good for months at a time. And if something goes wrong on the way to Mars there isn’t an easy, there’s, there’s really no easy way to turn around.

Host: Right.

Nujoud Merancy: You can shave a little bit off the time by trying to abort, but it’s not really a quick way home, any way you go to Mars. So being able to build up our systems and capabilities in that sort of stepwise fashion is fundamental to making Mars a success.

Host: Got it.

Nujoud Merancy: And we can also demonstrate, right, partial gravity operations on the Moon, partial gravity operations on Mars. You know, transitioning from long durations in space to the surface for the crew, huge challenge there, as well as the technologies and systems. A lot of the systems are very similar, whether you’re going to be on the Moon or Mars, there’s some differences for different things, but the Moon is absolutely a step towards Mars.

Host: Wow. OK. So then, Artemis IV and beyond, right? Like, I think this is part, part of the interesting thing is of course we talked about the lunar scientists who are just so ecstatic to get some of the samples, sample collection, all these, visiting various interesting locations for that is obviously going to be something, but the evolution of Artemis IV, you talked about this being a sustainable program, right, so this is where we really start seeing Gateway. This is really when we start pushing, you mentioned we’re starting with six-day surface operations going to 30-day operations, right? How from, from in your perspective, from a mission planning, how does that evolve over time to get more and more complex? What are, what are you guys working on right now?

Nujoud Merancy: So we’re already working with the Gateway program and all the other systems, right? So when we put Gateway out there that allows us to start staging things in lunar orbit, we’ll aggregate HLS and Orion at the Gateway, we’ll be able to do long duration, cislunar, microgravity operations that will be able to then feed into those surface operations. So where you’re talking about building systems out, and that’s where we, you know, Artemis IV and beyond is we, really where we start exploring, right? If you look at it, Artemis III is kind of like Apollo 11: can we get there? But after Apollo 12 and beyond, that’s when they really started doing the science. That was the exploration that was happening. So when we start at Artemis IV and beyond, we’ll really start building the systems, building the time in space and on the surface, and building up to those 30-day missions. So Apol, Artemis IV isn’t going to be 30 days, right? It’ll be a little while because we’ll need habitats on the surface, we’ll need rovers on the surface to get to those 30 days. So there’s more to come, yeah. The next one would be Gateway getting into orbit and being able to aggregate systems and logistics there, and then longer and longer surface missions.

Host: OK. So then what’s, you know, obviously – Artemis, Artemis I, talk, how, how is your group sort of excited for this mission that’s really going to help you to get to this point, right, because you’re making it very clear there’s so much work to do, even, even, even with thinking about Artemis II and III, I mean, that’s, that’s a lot of work, but IV and beyond, adding habitats and rovers, I mean, this is going to be like, at its peak, Artemis is just going to be so cool. I mean, I’m, I’m pumped just thinking about it. But I wonder, I’m wonder what, what it’s like from you guys?

Nujoud Merancy: I’ll be honest. It doesn’t yet feel real.

Host: Really?

Nujoud Merancy: Right. We’ve been working on this a long time, right?

Host: Yeah. Yeah.

Nujoud Merancy: There’s, none of this is easy and it doesn’t really matter who it is, what companies, NASA or not. It is a very big challenge and there’s a lot of us that have been working on it for a long time. So I’m not sure that it’s real until I’m at the Cape [Canaveral] watching the rocket take off, but trust me, I am really excited.

Host: Yeah.

Nujoud Merancy: And, and cannot believe, yes, we’re finally doing it. And it’s really like once you see the smoke and fire, we’re, we’re off and running.

Host: Are you, are you going to Artemis I launch?

Nujoud Merancy: I will be going to the launch.

Host: OK. I’m so incredibly jealous. You got to tell me, we’ll, we’ll have you on again after, afterwards, and you tell me if, if watching that rocket go up, if it felt real to you.

Nujoud Merancy: OK. [Laughter] When the rumbles in your stomach…

Host: When, when the rumbles, yeah. I’m going to wait for my invite to go out. I got to work. I got to work it from here, but, but…

Nujoud Merancy: I’m sorry. You’re going to…

Host: It’ll be cool. It’ll be cool. But just to feel that rumble.

Nujoud Merancy: It’s going to be amazing no matter where you are.

Host: I think so. I think so. A lots to learn, Nujoud. I think when you thinking about, you know, just kind of ending with this idea of exploration and just sort of why we do what we do, you mentioned working on this for a really long time, you know, and, and it’s not going to be real really until, until you do it. But if you work on something for a long time, you got to believe that you’re doing something important, it’s doing something cool. So if, when you, when you come to work every day and you start thinking about these Artemis missions and laying out the future of how humans will explore the cosmos, like, what, what’s really those driving factors that get you up every day?

Nujoud Merancy: I think you’re laying it out right there, right? You know, we get to make a difference. What we’re doing is important and it’s not just important for us or America, it’s important for humanity, right? Exploring isn’t just about the science return. It’s about the technology. It’s about the business. It’s about how do we, as a human species, come together? So getting to be a part of that is huge. And, you know, sometimes we forget because you’re in the day to day of it, and, you know, you just went to that meeting that did not go so well, but then you look up and you talk to other people and you realize how important it is. And so that’s why you just keep at it.

Host: Yep.

Nujoud Merancy: Right. We’re all in this because we believe in the mission.

Host: Yeah.

Nujoud Merancy: And it, you can’t understate how important that is.

Host: Wonderfully said, Nujoud. Thank you so much. This was awesome, as always, to have you on the podcast. [Laughter]

Nujoud Merancy: Thanks for having me back, Gary.

Host: Very, very exciting stuff. Artemis is, is, is, is, there’s a very fantastic future here and it’s very, it’s very cool to hear so much that’s going in from you to just this whole idea, and I hope folks are excited for Artemis I and, and then really, what’s, what’s coming next is it just gets more exciting every single time. It’s going to be really, really cool. So thanks for coming on.

Nujoud Merancy: Thank you.

[Music]

Host: Hey, thanks for sticking around. Always a pleasure to talk to Nujoud about the Artemis missions, about Orion. We’ve had her on a number of times. Actually, if you want to go back and listen to some of the episodes that we’ve had Nujoud on, first check out 116 where Nujoud and I compare the Apollo program to the Artemis program. And if you want to go way back, Nujoud was actually one of, one of our first guests, really, on the podcast. Episode 17, she gives an overview of the Orion capsule; also very relevant, even today. If you want to follow the Artemis I mission, we have a website for that, NASA.gov/Artemis-1. And of course, if you are really excited about Artemis programs after hearing our Artemis missions and, and everything that goes into Artemis, after hearing this episode, we do have a full collection of Artemis-related content. So go to our website, that’s NASA.gov/johnson/HWHAP/Artemis-episodes. Or you can just navigate to our homepage, Houston We Have a Podcast, and on the left navigation check out our collection. Of course, there are many podcasts across the whole agency that you can check out at NASA.gov/podcasts. Make sure you listen to some of their episodes as well. And if you want to talk to us, we’re on the NASA Johnson Space Center pages of Facebook, Twitter, and Instagram. Just use the hashtag #AskNASA on your favorite platform to submit an idea for the show or ask a question and make sure to mention it’s for us at Houston We Have a Podcast. This episode was recorded on August 19th, 2022. Thanks to Will Flato, Pat Ryan, Heidi Lavelle, and Belinda Pulido. And of course thanks again to Nujoud Merancy for once again 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.