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

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

For Episode 116 Nujoud Merancy, Exploration Mission Planning Office Chief, returns to the podcast to explain how the mission architecture of the Artemis program differs from Apollo and why it is important to develop a sustainable presence on the Moon. This episode was recorded on September 26, 2019.

Transcript

Gary Jordan (Host): Houston, we have a podcast. Welcome to the official podcast of the NASA Johnson Space Center, Episode 116, “Apollo vs. Artemis.” I’m Gary Jordan; I’ll be your host today. On this podcast, we bring in the experts; scientists, engineers, astronauts, all to let you know the coolest information about what’s going on in human space flight. We are returning to the Moon, putting the boots of the first woman, and the next man, on its surface within five years. It’s part of NASA’s Artemis Program and there’s a lot to it. Now one of the main questions you may be thinking right out of the gate is, how is this different from when we last went to the Moon? Fifty years ago we were in the height of the famous Apollo Program, the same program that put the boots of Neil Armstrong and Buzz Aldrin on the surface of the Moon, and redefined what was possible for all of humanity. One of the driving forces behind this initiative was simple, it could be condensed into a single phrase, beat the Russians. We were in the middle of a Cold War with the Soviet Union, not to mention the hot war in Vietnam, and though there were many interested in the value of exploration and discovery, the driving force was really political in nature. And that driving force defined the parameters of the Apollo mission’s structure. We had to put a man on the Moon and return him safely to Earth by the end of the decade, those were the driving political forces that put speed at the forefront. This meant that the spot that you would land would be quote, the easiest, the trip would be short so you didn’t have to bring a lot with you, and that you didn’t have to focus too hard on the longevity of the program. I’m not knocking Apollo, because with this profile, we redefined what was possible for human history. But now, even though we’re returning to the Moon, it’s in a totally different way. Not to give too many spoilers for this episode, but in the Artemis Program, everything changes; the spots to land will be numerous, and the mission architecture includes flexibility with how to reach these more interesting locations, the trips will be long, so we can gather a lot of scientific data about the Moon, and about living and working on another world, and the focus will be on sustainability, so the way that the program and its systems are built are meant to continue for years and gather valuable science. So here, to go into the weeds, or I guess into the lunar regolith, man I need to get out more, here to tell us all about the differences between Apollo and Artemis, is Nujoud Merancy. Long-time listeners may recognize her name from way back in Episode 17, where she gave an overview of Orion, which is the crew capsule of Artemis. Today she comes to us as the Exploration Mission Planning Office Chief, and she wrote an abstract about the differences between these two programs for the Human Space Flight Symposium that goes deep into mission architectures for both. So here we go, mission architectures of Apollo versus Artemis, with Nujoud Merancy, enjoy.

[ Music ]

Host: Nujoud, thank you for coming back on the podcast, welcome.

Nujoud Merancy: Thanks, Gary, glad to be here.

Host: You’re in a different role now, right? Because when we last talked was episode 17, about Orion.

Nujoud Merancy: Yeah, it’s been a while. And that time I was on the Orion Program Office doing mission planning but now I’ve moved over into a different office, but I’m leaving the office for Exploration Mission Planning, so a lot of the same stuff, but you know, worrying about a lot more of the things going on.

Host: Exploration Mission Planning, so it’s basically figuring out how the design of the mission is from start to finish.

Nujoud Merancy: Right, it’s the design of the mission from start to finish, including the ground systems, the Space Launch System rocket, Orion, the Gateway, the lander, all of those pieces have to play together, so we have to make the mission work from end to end, across all of the vehicles that will be executing it.

Host: And that mission is going to be Artemis, right? That’s the one you’re focusing on now. We are sending humans to the Moon.

Nujoud Merancy: Yes, Artemis is the new buzz word on the street.

Host: That’s right.

Nujoud Merancy: But it is a landing, the first woman and the next man, on the surface of the Moon, using the vehicles we have.

Host: Now we have a little bit of history here, with going to the Moon, with a little program called Apollo.

Nujoud Merancy: Just a little program.

Host: Just a little, yeah, and naturally I think it would be smart to compare the two, right? How did Apollo work, and how is Artemis going to work?

Nujoud Merancy: Well and not just for us, but a lot of people on the street are saying, well why is it different than Apollo? So I think that’s what we’re here to talk about, because we’re getting those questions a lot.

Host: Right, and you spent the time putting down notes on comparing the two, right? You actually drafted this paper that explores how, what the design of Apollo, the mission design, the mission architecture of Apollo was, and then what we have to do for Artemis to make that successful.

Nujoud Merancy: Right, so the mission design, you could say well we could do it exactly the same way, but that’s to a different purpose and so I wrote a paper, it’s going to the International Astronautical Congress in a few weeks, but that’s, it’s a congress, a big conference with all of the space programs, people come and talk about all sorts of things, but I thought that’d be a good venue that we could actually have this discussion a little bit more.

Host: Perfect. Well let’s dive right into it.

Nujoud Merancy: Alright.

Host: Starting with Apollo, because I feel like a lot of people are more familiar with Apollo, just, I mean besides just Neil and Buzz going on the Moon, you know, one small step for man, I mean the whole idea of going to the Moon, it was a different framework and I think a lot of that was because the drive was so, you know, you had to do it by the end of the decade, right? There was a timestamp on it. And there was that drive to do it quickly, there was that drive to do it efficiently, and those were sort of the main drivers behind the Apollo Program.

Nujoud Merancy: And the drivers to do it quickly were, you know, we look back with rose colored glasses, but it wasn’t about exploration for the sake of exploring, we were in a space race with the Soviet Union at the time, so there was a drive to do it very quickly, really from a militaristic background, so do it quickly and along the way, you’re inventing a lot of technology. So they weren’t, no one, there weren’t big communication satellites, we hadn’t launched tons of rockets, we’d barely put anyone in space, and yet we were trying to go to the Moon, so you don’t try to do super ambitious programs, you try to do what is the quickest way to get there. And that’s really the defining future of the Apollo mission design.

Host: Right, it was, I mean if you’re going to do it in that span of time, one of the things I liked about your paper was you have this phrase, “minimizing performance demands”. I like that phrase because you’re saying, you know, how could we do this efficiently, you don’t have to have this sort of flexibility, it’s just, we’re going to design the mission to do exactly this, right?

Nujoud Merancy: Right, it was, you can land anywhere on the Moon, so if you can land anywhere, well you land at the easiest place on the Moon, and the easiest place to land on the Moon is near the equator, and that’s just the physics of it, you know, when you send the trajectory from Earth, you launch from the equator, the Moon is in equatorial plane, you go for the equator of the Moon, and that’s the easiest performance to land on, you need the least amount of propellant and delta velocity to get to the Moon at the equators, so that’s, that was the goal.

Host: That was the goal and that’s why they picked the landing site they did, because we want to save fuel, we don’t want to use a lot of it, again, minimizing those performance demands. So here’s where we can go into orbit with using the least amount of resources, pick the spot where it will be the easiest to land, right? The least amount of obstruction, not the most interesting place to land, but the easiest to land.

Nujoud Merancy: Yeah, and certainly on Apollo 11, they landed at the easiest place. They flew on a free return trajectory, which means you could have only landed within five degrees latitude of the equator. They picked a nice, big open flat plane, so there wouldn’t be any obstructions, you know, they literally picked the easiest place to land. And once they did it, they could go a little bit more aggressive on the subsequent flights, they went up to the higher high lands about 20 degrees latitude off, so they could push it a little more once you were on the subsequent ones but overall, it was still the general easiest target on the Moon.

Host: Yeah, and then you armed the lunar module with some of the best pilots you can find, because Neil Armstrong, famously, as soon as he tilted down and actually saw the lunar surface, was like, we’re not going to land in that–

Nujoud Merancy: There’s a whole bunch of rocks in the way!

Host: Yeah, so that’s why you put a nice pilot on there because we want to eventually get to that easy landing spot, because the technology was, again, minimal, you just, it was just enough technology to do it safely and to get back, but you know, you have to be ready for anything that could come your way because you’re right, you don’t have the nice infrastructure of travel in space like you do, I don’t know how it is today exactly, but, especially in Low Earth orbit, but going out, I mean like you said, you have to design everything from the ground up.

Nujoud Merancy: It really was from the ground up. They had to build the VAB, the big vehicle assembly building, they had to build launchers, they had to build, they had put ships in the ocean with communication radars on it and so you could actually communicate. There wasn’t ground infrastructure for the comm like we have today. Now, we take it sort of for granted because we have a whole deep space network that talks to the rovers on Mars and this and that. But they were starting from scratch.

Host: Mm hmm.

Nujoud Merancy: So you literally, they had Navy ships sitting out in the ocean to cover the communication from the Moon. So there’s all those things they were doing from scratch, so you couldn’t spend a lot of resources on fancy things.

Host: Right.

Nujoud Merancy: So you went for the best way, the cheapest way to get it done if you will.

Host: So, coming from the ground, having to build this literally from scratch, they had this part in the Apollo Program called the Reference Missions. What was that?

Nujoud Merancy: So a reference mission is what you always sort of you start with and say, this is my plan and now I’m going to build the pieces to do it. So a design reference mission is your baseline mission plan and then you execute, you have to decompose that into well, I need a rocket that’s going to have this performance, I need a spacecraft with this performance, you know, the capsule will have to do this. And then you can trade between them as the design goes, but you’re trading against that design reference mission. So the design reference mission for Apollo was that equatorial landing site, with the free return trajectory, it was putting two people on the Moon, and doing it for, you know, just if you literally Apollo 11 was only on the surface of the Moon for a few hours. It was measured in hours. And then subsequent flights that could go a few days, but you weren’t trying to do long duration, multi-month missions to the Moon. It was get to the Moon, pick up some rocks, and come home again.

Host: That’s it, so, the free return trajectory, correct me if I’m wrong, was one of several trajectories that they were considering when they were trying to come up with a reference for what is the easiest and what is the rocket that we need, or rockets that we need, depending on the profile of how we’re actually going to make this happen.

Nujoud Merancy: Yeah, and the free return is really a safety thing, because if you’re on a free return trajectory, and say you had a problem with your service module main engine, you would fly by the Moon and the Moon would slingshot you back to Earth. It’s the Apollo 13 scenario. And so it uses the Moon’s gravity to send you back to Earth and you don’t need a big burn out of your engine to get home again. So the first couple flights to the Moon, that’s what they used, they stayed on that free return because we were still demonstrating that all the systems worked. And then actually starting on Apollo 13, they stopped using the free return because they, you can’t use it to go to those higher latitudes on the Moon, so once they had a problem on Apollo 13, they had to do a burn to get back to the free return so that they could get home before they ran out of power in their capsule. So there was a whole bunch of situations going on, so, but yeah a free return was the design reference mission being used initially.

Host: Wow, now there was another one and I might be confusing this, so just, so just steer me to the right course as I’m saying this, but, the lunar orbit rendezvous was one of many that they were considering because I think there was an Earth orbit rendezvous, there was a, there were all these different profiles when they were thinking, you know, how can we actually, how can we actually get to the Moon. So, how did that work? And how, why did they select lunar orbit rendezvous?

Nujoud Merancy: Yes, so that’s its own fun story, right? So, there was, there’s essentially three ways; you could go direct, where you have one giant rocket, leaves Earth, lands on the Moon, takes off again and comes home again. So just one piece. So but in order to do that, you need a really big rocket because you need all that fuel to control your landing, and then that structure where, that held all that fuel, you’re going to take off again with it so you end up with a really big rocket, just to do the math of getting there. And then there’s something called the Earth orbit rendezvous, where you’d launch two rockets from Earth, meet up in Earth orbit and then go to the Moon, but then you’d still land one rocket on the Moon and come back. Or there was lunar orbit rendezvous, which is ultimately what was selected and that was actually John Houbolt went above his managers head to recommend it back to headquarters so it was its own thing that he actually had been turned down from talking about lunar orbit rendezvous again, wrote the technical paper, management ended up agreeing and implementing it, but it was very controversial at the time because we’d never rendezvoused two spacecraft in Earth orbit, but yet here we were talking about landing a spacecraft on the Moon, leaving the command module in lunar orbit, and then having the asset module leave the Moon, rendezvous and dock with that command module in lunar orbit, and then come home again. So you had multiple pieces, you have essentially broke your vehicle up into three pieces in order to pull this off, but what that does is let each element be a lot smaller and that’s where you get all your savings and you can make your rocket on Earth smaller because you launched smaller pieces from the Moon. So it’s all a game of math and the bigger you have to land on the Moon, the bigger the rocket you need on Earth and ultimately that enormous Earth rocket, as big as Saturn 5 is, trying to launch a direct size vehicle would have been just astronomical.

Host: Yeah, you know, that lunar orbit rendezvous sounded complicated but then when you actually sit down and think logically about it you’re like, huh, this is probably the smartest way to do it.

Nujoud Merancy: Right, it’s a very elegant solution, you just have to do more things in lunar orbit, which initially wasn’t a favorable thing because we’d barely done anything in Earth orbit.

Host: It was risky.

Nujoud Merancy: It was risky, so you had to accept a little bit more risk on the backend but it made your vehicle sizes feasible in the end.

Host: So, now let’s get into the nitty gritty of how this actually worked. We selected the lunar orbit rendezvous, we’re doing an Apollo mission, we need the Saturn 5, the Saturn 5 is going to carry all of those elements that you just described, starting there to carry x amount of mass to this orbit of the Moon.

Nujoud Merancy: Right, so the big Saturn 5 rocket, the whole purpose, three stages of it, were to launch the three pieces you needed at the Moon. So this whole thing was a direct launch though, because you used one launch to launch your command module, your service module, and your lunar module, which included both an ascent and descent element. So you used one launch to go directly to the Moon, land on the Moon, and come home again. So it was a very performance optimal, right, minimum performance option of how do I get someone on the Moon. So, and putting it all on one rocket at one time, is the best answer for that.

Host: There you go. So, you put it all on the rocket, you get into Low Earth orbit, now you’re in your circling the Moon, you have a third stage because the rocket is so big–

Nujoud Merancy: You’re circling the Earth.

Host: What did I say, did I say the Moon?

Nujoud Merancy: You said the Moon.

Host: Ah man, I’m already at the Moon. Circling the Earth, there we are, now we have this third stage that is going to perform something that’s very critical when it comes to lunar exploration, called trans- lunar injection, and that is going to carry all of those elements that you just described in one big burn to get to the Moon, right?

Nujoud Merancy: Right.

Host: OK, so that was a huge part of it.

Nujoud Merancy: Right, so the third stage sends your three pieces to the Moon, and then the service module on Apollo actually inserted into lunar orbit, and we used 100 kilometer, or 60 nautical mile orbit, so you’re pretty close to the Moon when you’re circling it, and then the lunar module undocked with two people on board and they do a controlled power descent, so that’s really the flamy end of the rocket first towards the Moon, you set it down nice and gently, and then you leave the descent stage, after you’ve done all of the things you’re going to do on the surface, so now you leave some of that mass behind, and that’s the whole point of having two pieces there, is now you’re a much smaller element, the ascent module took back off with the people to come back, rendezvous with Apollo in lunar orbit, and then Apollo would perform the trans Earth injection which is the burn you need to return safely to Earth.

Host: There you go, and so, when it came to power, when you needed to actually perform that whole thing, as you just described, going to the Moon, landing, coming back, the power you needed was only for a few days, so you didn’t need to have a system that was going to, you know, over perform and provide power for months and years, you had fuel cells.

Nujoud Merancy: Yes, so Apollo, because it was only going to operate for a maximum of 11-14 days, they used fuel cells, which is the same thing the shuttle used actually, where it uses a commodity onboard hydrogen and creates power through the chemical reaction of the chemicals on board and then produces energy and actually water as a bi-product. But by doing that, you can only produce power for as long as the tanks you had that you took off with. So, the reason to use fuel cells is they’re pretty mass efficient, which means they’re lighter, but they’re only good for a couple weeks at a time before you run out of your stuff to make power with.

Host: And so another constraint was, not necessarily constraint, but when you’re designing this mission, you talked about the crew module, no, yeah, command module sorry, command module was going to continue to orbit the Moon while two astronauts went down in the lunar module to land on the surface and then explore through EVA, you only needed one person in that command module, so this whole mission is designed for three people max.

Nujoud Merancy: Right. Three people max is all you could fit in the command module of Apollo, two people to the surface, one had to stay in space in the command module because this is 1960’s technology, right? They barely had enough software to run the guidance computer, they didn’t have fully automated iPhone apps that could command it all. So someone literally had to stay on board just to keep the Apollo vehicle running while the others were gone. So, one person stayed on board, and then because of that you know, you have a very small command module, you’re trying to minimize mass, they only had enough food, water, oxygen, on board, you only make the tanks as big as you absolutely have to so they only had about 14 days’ worth of supplies on board for that crew. So you can’t stretch the mission, there was no way this mission could go for many months.

Host: That’s another key point, is when you’re designing the life support systems, they’re tanks, you just take everything you need with you because you only have a finite number of days that you’re going to be there. They don’t have to be the life support systems like you see on the space situation now which are just constantly running, because you need to operate for 20 years continuously.

Nujoud Merancy: Right, yeah, they have tanks of water and tanks of oxygen, and when they were out, they were out. So you had to be home before you were going to run out of those, that’s part of the mission planning right there.

Host: I do have a, this is something that I’ve always been sort of confused on but probably shouldn’t be, whenever the lunar module actually went down, you had the just, like you said, the descent and the ascent modules, or parts of the lunar module, those were two separate fuel tanks, right? So the descent had a certain amount of fuel to do that job, and then the ascent had a certain amount of fuel to do its job.

Nujoud Merancy: Correct, they both had their own fuel tanks and their own engines. So one of the interesting things is that ascent module was used once during the flight, to get off the Moon, and you couldn’t test it, so you better hope it worked, because once you set down on the Moon, it was actually buried inside the descent module so you couldn’t test fire it before you went down or anything, you’d burn your descent module up. So literally you went to the Moon and you were going to use that engine and it had to work when you were ready for it because there was no chance to test it before you landed.

Host: See, when you say these things, it just shows me how amazing these astronauts were to actually go and do this, because there’s so many unknowns about the whole mission. But yeah, even–

Nujoud Merancy: Got to trust your engineers.

Host: Got to trust your engineers, exactly. You know, you talked about computer issues, the reason that we have to have a person in orbit there, you talked about the fuel, only a very finite amount of fuel, these were all very, very key moments of the Apollo 11 mission. When they, when Neil Armstrong had to take the controls of the lunar module and descend towards the surface, he was running out of fuel and running out of fuel fast, he did not have a lot left, I think it was 18 seconds–

Nujoud Merancy: Yeah, it was in the, you know single seconds of, you know, counted on your hands

Host: And then on top of that, you had those 1202 alarms going off, which was a computer overload issue because they literally couldn’t handle the amount of data that was, I mean, this was just like, almost archaic now when you think about it, but it was the way that had to be done to achieve these minimizing performance demands.

Nujoud Merancy: And that truly was state of the art, what you were doing.

Host: That is true! Computers were a new thing.

Nujoud Merancy: Right, computers were pushed along there. And also in terms of performance because you left the Apollo module in orbit, the Moon, as it’s going around the Earth, means that orbit is shifting its orientation towards the Earth, so it had to keep, and it shifts its orientation around the Moon, so it has to stay above the site where the lander is. So it has to keep doing burns to adjust its orbit to stay above the lunar lander so that the lander could even get back to it. So part of the propellant and the performance is how much, how long can the command module do that. So part of the constraint on how many days you can spend on the Moon was the propellant in the command module, staying above the lunar lander so they could come home again.

Host: And it had to maintain that orbit to A, be in the same plane, but B, be predictable. Because I know the lunar module had, even after it landed, they weren’t celebrating at mission control because they had several periods where if something were to go wrong, they can fire that ascent stage and re-rendezvous with the command module a little bit early, just in case. So that orbit had to be predictable.

Nujoud Merancy: Yeah, so you had to keep the command module in its very known location in a very certain way so that the ascent module could even get back to it, so part of the duration for the surface constraint is the ascent, or the command module having the prop to keep doing that. So it was only a few days’ worth of prop on board for that as well before you would have to come home.

Host: So then when you did come home, they rendezvoused in orbit like you said, and then they had a trans-Earth injection to get back to Earth. Now I believe they just, they didn’t, once, they didn’t reenter into Earth’s orbit, right? They just, they went into the atmosphere.

Nujoud Merancy: Yeah, it’s called a direct entry–

Host: Direct entry.

Nujoud Merancy: So, you left, you actually jettisoned that lunar module, ascent module, around the Moon.

Host: That’s right.

Nujoud Merancy:So it crashed back into the Moon, you didn’t carry that mass home with you, and then as it comes back to Earth, the command module separated from the service module, only the command module landed safely and the service module, of course, broke up on reentry and splashed into the ocean.

Host: Mm hmm, and they chose the ocean for, I guess design purposes?

Nujoud Merancy: Yeah, it’s a, there’s no rocks in the ocean.

Host:Yeah. [Laughter]

Nujoud Merancy:Or at least they’re really far down so you’re not going to hit them. So landing in the ocean gives you a nice, predictable surface, where you’re not going to land on a rock and crack your command module open or hurt your crew. So they landed in the ocean, near the Pacific, in the middle of the Pacific Ocean, really and a Navy ship would be stationed, waiting for them.

Host: And why the middle of the Pacific Ocean?

Nujoud Merancy: Well, it was really just to make sure your service module doesn’t land on anything, number one. But also they had a, they didn’t use a skip in entry like we do today. They came in direct so you needed to have room for that landing and you would move the ship to be where it is. So they landed and then, you know, they had full control over the Navy because this was National Security interest so they could, the Navy would support whatever was needed, wherever it was needed.

Host: Nice, and so that provided you a little bit more area, you didn’t have to be as accurate when it came to the landing.

Nujoud Merancy: Correct. You could have a much larger zone for landing.

Host: OK, so this mission profile, the mission profile of Apollo, what was good about it, to meet the needs of the time?

Nujoud Merancy: What was good about it was by putting it all on one launch, while you limited where you could go on the surface of the Moon, it was one launch, so that way you had the least amount of resources assigned to it, the least amount of risk, even though there’s a lot of risk still, you only had one launch to get it up there, but as a result, you were very limited on how long you could stay, and how much you could take, which was only three people for a limited stay of a couple days.

Host: So why won’t this mission profile work for what we want to do with Artemis?

Nujoud Merancy: So one of the big differences between Apollo, which was get to the Moon as fast as you can, as quick as you can, it is for Artemis, we want to be sustainable, which means we want to be able to explore for longer durations, potentially you could build bases, but also you want to demonstrate things you need to go to Mars. And all of the things you need to go to Mars, involve much longer durations, surface stays on Mars are basically 30 days to 6 months, so you need to be able to do long duration stays and have a long-term buildup of stuff, because you need a lot more stuff, the longer you’re going to stay. So it’s a very different goal between Apollo and Artemis.

Host: And complicated, now when you stay longer and you need more stuff, that’s all more complicated stuff.

Nujoud Merancy: Exactly.

Host: So let’s go into Artemis. There are still a lot of unknowns about exactly how this is going to work, right?

Nujoud Merancy: Absolutely. So there’s, I mean we don’t even know who’s going to provide the lander system yet. The contracts are out for bids, and things like that. So there’s a lot of unknown, so this is really a discussion of the potential and not a fixed mission profile for the future.

Host: Well let’s get into it. What are the key components of an Artemis mission?

Nujoud Merancy: So the key components of an Artemis mission; first you start with SLS and Orion, so we’re demonstrating those in Artemis 1 and 2, so that is the first crewed vehicle beyond Low-Earth orbit since Apollo. And so that will be taking the capability to take crews to and from lunar orbits, so that’s the first part. The second part then is which orbit around the Moon? So right now, we’re planning for the Near Rectilinear Halo Orbit, which if you looked at the Moon, looks like an orbit that goes North – South on the Moon, rather than around the fat part, the equator if you will. And so it is really close to the Moon at the North Pole, and it’s really far away from the Moon at the South Pole. So it’s a very different kind of orbit than people are used to talking about.

Host: If you were looking at the Moon during the full Moon and you could, in this fake scenario, actually see this thing moving, would it be more moving North to South or South to North?

Nujoud Merancy: Well, it’s both, so it’s, you’d be looking at the oval, and so on one side you’d be going North, and then you’d come around the top of the Moon and head South. And you’re just really close at the top of the Moon, at the North Pole, and then really far away at the South Pole and so, the whole orbit takes 6 1/2 to 7 days.

Host: Okay.

Nujoud Merancy: To make one orbit of the Moon. So you spend most of your time dwelling below the South Pole, in the bottom part of that oval that you’d be looking at.

Host: Right, because it stretches really far down that way.

Nujoud Merancy: Right.

Host: OK, OK, so now you’re entering into an orbit there, and I think one of the reasons you want to do that is because there’s this new thing, that’s different from Apollo, called a Gateway.

Nujoud Merancy: Right, so the Gateway is basically a little mini module or station setup with a power and propulsion element and what will be the halo, which is just a small logistics and outfitting module, really think of it like a node on the space station, where you had multiple ports on it. And that’s there because we need to be able to prototype Mars habitats and things like that so that’s really there to start building on those other technologies you need to go beyond the Moon. So we can use the halo and the PPE as a Gateway, to dock the lander and dock Orion too, and so that’s part of the notional plan for the future.

Host: OK, so what is nice about having this Gateway in orbit versus must the command module and the lunar module?

Nujoud Merancy: It gives you more options to get stuff up there. So you have suits, you need all those science equipment’s, you need lots of commodities for what you’re about to do, so it’s launching logistics as well that you’ll need for the Moon.

Host: And that’s a bit part of Artemis, right? Is stuff we’re bringing more stuff and we’re doing it for longer.

Nujoud Merancy: Right, if you want to stay on the Moon for longer and do more science, you’ve got to have a lot more stuff.

Host: There you go. Now the profile that we’re going to explore today assumes a three piece human lander system, right?

Nujoud Merancy: Yeah, so for now I’m using the three piece lander, you could launch those on commercial rockets, or however you want to get them up there, but you still need a lot of gas to get from NRHO down to the Moon, you need a lot of gas to get from low lunar orbit down to the surface of the Moon. So, it takes, the Delta V as in total on the mission, is about the same whether you went to low lunar orbit, it’s just who’s providing it is the– in the Apollo scenario, the Apollo service module provided a bunch of Delta V, in this scenario, we’re using more of that on the lander to provide the Delta V, Delta Velocity, to get to the surface of the Moon. So Orion does its part to get to NRHO, the lander does the part from NRHO to the surface.

Host: Got it. OK, because you need to, it sounded like you needed to change orbit, you needed to go from this Near Rectilinear Halo Orbit to low lunar orbit, right? And that’s part of the work horse of the lander.

Nujoud Merancy: Yeah, part of the work horse of the lander is first you adjust your orbit to get it down to low lunar orbit, and that allows you to setup for where you want to land. And then you go from low lunar orbit down to the surface. So I mean, you could go very direct but it’s a little bit more complicated just for the guidance of making such a huge change. So you want to pause, you’re really just pausing in low lunar orbit and then you continue down to the surface.

Host: OK, so there are, if we wanted to explore these three pieces, the way you laid them out was transfer, descent, and ascent elements. So what would they all do?

Nujoud Merancy: Right, so the transfer element would be what takes you from NRHO to low lunar orbit, the doesn’t element takes you from low lunar orbit to the surface of the Moon, and then the ascent element would take you from the surface all the way back to NRHO to rendezvous with Gateway.

Host: Alright, so all of these elements have to do with switching where you want to be.

Nujoud Merancy: Right.

Host: Yeah.

Nujoud Merancy: It’s all the intermediate staging of getting there.

Host: OK. Now another thing that this profile assumes is the type of SLS built that you want to use, so there’s several stages in the development of the space launch system, there’s Block 1, and Block 1B, that you explore in this so what is the differences there?

Nujoud Merancy: Well Block 1 is the one we’re launching on Artemis 1 and 2, and it’s, Block 1 launches Orion to trans- lunar injection. So that sends Orion to the Moon on its own. And you can do this mission off of Block 1, so really, it’s an either – or. If you get Block 1B, you could use it in the future, and what Block 1B is, it makes a bigger upper stage, called the exploration upper stage, and that would allow you to launch Orion and another co-manifest payload, like a logistics module, that Orion could carry with it to that Gateway. So, it’s really the mission profile works very similar whether you’re using an SLS Block 1 or a Block 1B, but it’s how much extra stuff you can take with that Block 1B. And you have more launch opportunities on Block 1B, because of the earth’s staging that you’re doing.

Host: OK, so, there is different types of orbits here, and this is where I just sort of kind of don’t really understand, but there is 100 nautical miles circular orbit for Block 1B, and there is a very elliptical orbit that would be used for Block 1, so that was part of the differences that I saw in if you were using a different construction of the SLS, how that would vary for this lunar mission.

Nujoud Merancy: Yeah, on a Block 1, we launch into a very elliptical Earth orbit so right now it’s 100 by 1450 nautical miles. And so what that means is when you go to the Moon, you have to point that high end, your 1450 nautical mile Earth staging is sort of pointed at the Moon and that’s where we use the core stage to push it up as high as you could and then the ICPS, the Interim Cryogenic Propulsion Stage, makes up the difference to get to that trans lunar injection. With the larger exploration upper stage, the, you go to just 100 nautical miles circular orbit and then you can, the Moon can be in any direction because it’s circular, any one of the directions of that orbit are equally good. So that’s why you can launch more often on a Block 1B to the Moon, because it doesn’t matter where the Moon is, relative to the Earth orbit.

Host: Okay, now, let’s build this profile and assume that the Gateway and the lander are already there in the Near Rectilinear Halo Orbit. So what is the, I guess, transit time, what is the, what is the profile for if you were to launch from Florida and perform an Artemis mission?

Nujoud Merancy: Yeah, so SLS would take off with Orion, whether, regardless of which version you’re on, Orion would use a variable transit, so you can go in as fast as six days or as much as you know, 12-14, and that’s also that by the time you arrive in the Near Rectilinear Halo, you arrive at the same point in the orbit that Gateway and the lander are waiting for you. Because we said that orbit was seven days long, so if you arrive and it’s on the opposite side of the orbit, you’re not there, you can’t rendezvous and dock, so you have to arrive in orbit at the same place the Gateway is. So, and that’s called rendezvous targeting.

Host: OK, so if you were, let’s take a mission, let’s do an Artemis mission, we can use a Block 1 or a Block 1B, whatever, but you have this trans-lunar injection with all your stuff that you’re taking to the Gateway, so now you have to make sure that the timing that you actually get to that orbit, times out perfectly with where the Gateway is going to be so that, because that is stop one, stop one is the Gateway.

Nujoud Merancy: Right, stop one is Orion docking to the Gateway in that Near Rectilinear Halo Orbit, because Gateway has your lander attached to it. So Orion docks with Gateway, all of that timing is correct, and then the crew can get into the Gateway, unpack all their stuff, get the lander ready to go, and then stop two is the lander actually separating from Gateway to start heading down to the Moon.

Host: And in this scenario, we have packed Orion with four crew members.

Nujoud Merancy: Right, Orion would take all four crew members, for 2024 we want to just, we’re trying to just put two people on the surface of the Moon, so two people would remain on Gateway, two people would go down in the lander to the surface.

Host: OK. So that is part of the, I guess design of Orion why we have four people or is it the needs of, we need two people in Gateway and we need two people to ride this lunar lander?

Nujoud Merancy: So, it’s really because Orion can hold four people, and the long-term planning as we talk about wanting to be able to be sustainable and do long-term exploration, is that eventually you want to be able to land all four people on the Moon. But as you build up your vehicles and capabilities, that added mass, now you know more, you can land more people, things like that. So the first attempt is to land two people, but Orion can take all four with them to start the mission.

Host: So interesting, so in this, if that is the goal, then that means that the design of Gateway will be so that it does not need to have people on it all the time.

Nujoud Merancy: Right, I mean Gateway is there all the time, like the space station, except unlike space station, you need no human tenders for long durations in between visits. So the Gateway, now with our modern software and computers, all of our telecommunications infrastructure, the Gateway will be designed to be completely untended or at least only tended by flight controllers here on the ground, during long stretches without people.

Host: OK, so let’s take a ride with these two astronauts that are descending towards the lunar surface and they have, let’s just assume that the three elements of the lander, so they are going into the low lunar orbit and then they’re going down to the surface, what is that mission profile to make sure you know, just like Apollo, where you had to time when the lunar lander and the command module were, how long can they be on the surface?

Nujoud Merancy: So that, the interesting part about this, so as we’re trying to aim for the South Pole, because that’s where we think the most science is, so this is a science driven mission, if we land on the South Pole, where we think there’s water, ice, there’s permanently shadowed regions where that ice may exist right there on the surface of the Moon, so the goal is to land on the South Pole, so you time your departure from the Gateway to insert into a low lunar orbit, but this time it’s polar, so for Apollo it was an equatorial orbit, for Artemis they’ll insert into a polar lunar orbit, which means it goes North – South instead of East – West, around the Moon. And then they’ll descend and land right there on the South Pole, so if you’re looking at the Moon, they’d be hanging off the bottom like that.

Host: So, this is another key component of Artemis, is we are no longer choosing what is the easiest landing site, we’re choosing what is the most interesting.

Nujoud Merancy: Exactly, that is probably one of the primary drivers right now, we want to go for the science, we want to go for the exploration of it, so we’re not picking the easiest part, we’re actually picking probably the hardest part, because it’s polar orbit instead of equatorial.

Host: And I guess with being, having to land in the more interesting area, you would want to spend more time there.

Nujoud Merancy: Right, and part of the spending more time there is that you’re actually waiting for the timing to get back to the Gateway. So you’re in that 7 day orbit, so you want to time, you want to maximize your time on the surface so you’ll get 6 1/2 days on the surface, before you need to take off again to arrive at that point in NRHO where the Gateway’s waiting for you again. So all of this is timed on the best timing for again, as little performance as you have to have, so you don’t have unlimited fuel supply so you want to time things so you can, you know, make things ideal for your vehicles instead of making it hard. So we still have to worry about performance, even though Apollo did, but we’re landing in a harder place, so now your performance is about getting to that harder place on the Moon in this case.

Host: OK, harder place on the Moon. But this is going to be sort of the, I guess we’re assuming this is the kickoff of the Artemis Program, right? This is like landing number one.

Nujoud Merancy: Well, this would be the third Artemis flight, because you will have launched SLS and Orion, twice. But Artemis 3, would be the first landing on the Moon, yes.

Host: Got it, OK, but then after that, it can be like Apollo and just get more complicated over time as you need to do more on the surface.

Nujoud Merancy: Yeah, once you’ve done it the first time, now you can start OK, well this worked really well so I have more margin here than I thought, and I can you know, scale back on some of my needs here because we didn’t use, say as much oxygen or something. So you can actually get harder on subsequent flights once you’ve proven your hard work out.

Host: OK. So, now you’ve explored the surface on, is it, will it be Artemis 3, is that? Or is it something else?

Nujoud Merancy: Well this is Artemis 3 mission.

Host: This is Artemis 3, OK, so this, on Artemis 3, you’ve done your lunar exploration and now you are lifting back off to the Gateway, how do you get from Gateway to Earth?

Nujoud Merancy: So you get back to Gateway, and this is actually very simple, you get back in Orion, and then at the right point in the orbit, you leave the Gateway and Orion takes you home again, doing the trans Earth injection burn.

Host: OK. In the Near Rectilinear Halo Orbit, just kind of separate and do your own they?

Nujoud Merancy: There’s kind of two burns; first you separate and you do a departure burn from that orbit, and you actually fly back by the Moon at 100 kilometers, or 60 nautical miles, and then you do a burn as you fly by the Moon to target Earth again. So it’s two burns, one to leave the orbit, one to fly by the Moon and target Earth, but that all is 5 days from the time you leave Gateway until you’re back at Earth.

Host: OK. And this, it’s sort of the same profile on the way back, you’re flying back with Orion, on the way back Orion separates from service module and then kind of like Apollo, you go right into the atmosphere or now we’re doing something different?

Nujoud Merancy: You directly enter the atmosphere again, so we come right back in, except this time we’re using a skip entry, so we land just off the coast of San Diego, so sunny San Diego, is awaiting the crew, and we do that because we actually use the atmosphere to skip through the atmosphere and guide the vehicle so it’s, it’s really flying itself with the lifting body while to target that, so you’re targeting a 10 kilometer circle essentially in the middle of the ocean, not the middle, the San Diego coastline.

Host: Yeah, so it’s more accurate.

Nujoud Merancy: It is very accurate landing and then, and actually most of that 10 kilometers is the wind pushing the parachutes around.

Host: Oh wow.

Nujoud Merancy: If you weren’t under parachutes, you’d land in even much more tight area.

Host: Oh, wow.

Nujoud Merancy: But we kind of need the parachutes.

Host: Yeah. Alright, so there you have it, there’s an Artemis mission from start to finish. There are certain, I guess, constraints and different ways that we have to think about the Artemis because as we’ve alluded to, sort of in the beginning of our talk, space has changed. Now we have different ways to communicate with things that are going out to the Moon, we have more, better technologies, so let’s kind of go into some of those, some of those constraints based on what Apollo kind of had to encounter and deal with their technology, and what we’re dealing with. And I guess we can start with communications.

Nujoud Merancy: So communications is a really fun one. So during Apollo, there weren’t communication satellites in orbit, there weren’t TDRSS, which is you know, the data relay satellites that shuttle and station use. You know, you were using ground antennas, there wasn’t a deep space network at the time, so one of the big constraints on Apollo was, you had to land on the face of the Moon, facing Earth and you had to land no more than about 20 degrees north or south latitude, so you’d have the right communication with Earth direct line of sight during landing, the approach to landing, and the time on the surface. So once you just cut out the comm, you’ve cut out about 80% of the Moon, to have available landing sites during Apollo.

Host: OK, now what are we looking at with Artemis?

Nujoud Merancy: So with Artemis, you get two things; first, we have the Deep Space Network, so you can land really anywhere on that front face, but one of the advantages of that Near Rectilinear Halo Orbit that Gateway in, is Gateway can act as a comm relay, so the whole time it’s below the South Pole, the lander can talk to Gateway and Gateway can talk to Earth. So now you can land on that South Pole, almost all of the time, because Gateway could act as a relay, so you sometimes you have direct line of sight from that South Pole to the Deep Space Network, sometimes you can go through Gateway, but really, now with modern technology, the communications isn’t really an obstacle. And if you really needed to, you could put a, just a little communication relay satellite out there with Gateway and you could have full coverage of the Moon all the time.

Host: Alright, so more options, that’s what we’re looking at.

Nujoud Merancy: Lots more options now.

Host: Which is big for exploration and science, now we can go towards those really interesting areas, find out what’s on the surface and areas that we couldn’t cover before because we have the technology now.

Nujoud Merancy: Right, and now we have that technology so you can land, just like they do on Mars, you can put rovers on there, which is what some of the commercial lunar payload service contracts are to put some un-crewed rovers on there to do science even before we can send humans. So there’s lots of options now with modern technology you didn’t have in Apollo.

Host: OK, and even the trajectory has changed before with the constraints with the trans- lunar injection. Apollo, I believe was very constrained on what they can do and then with the SLS, I think there’s maybe a little bit more flexibility and you already alluded to it, doesn’t matter where the Moon is.

Nujoud Merancy: Right, so when Apollo, the Saturn 5 launched, there’s no tracking stations out there in the middle of the ocean and they didn’t have relay satellites in orbit, so they actually literally put a ship off the coast of Florida and you only had about 26 degrees azimuth so that’s you know, the North – South launch angle that it took off from Florida at, so it had a very narrow window to launch into, now we have tracking stations in Bermuda and at KSC, as well as TDRSS [Tracking and Data Relay Satellite System] in space so there’s a much larger swath of ocean you can launch over with the added communication just on the ground as well.

Host: Wow, OK, yeah. There’s, it’s more technology, more flexibility, more options, this is all awesome. Now, I think a big distinction between Artemis and Apollo, it may sound small but it actually is significant, is the number of crew. With three people and with four people, it doesn’t sound like much, but with more people comes more mass, more stuff you need, right? So there’s differences there.

Nujoud Merancy: Yeah, so Apollo, with three people on board, and that’s like all they could fit in that capsule, Orion is a little bit bigger, it’s about a meter wider, and what you can do with that, when you say you’re going to put an extra person on you’re like well how much can they weigh? You know, 200 pounds, right? Pretty much average. But, with that 200 pound person, they need a seat, they need more oxygen, you need more water, they need food and clothes because everyone else gets food and clothes, so that ends up being over 1000 pounds extra per person you put on there, and the space you need for them. So you need a bigger capsule volume because, just literally because you put a fourth person in there with everyone else. So Orion is bigger, it was the design to be bigger to carry those four people, and there was I’m sure a lot of trades long ago about why we’re going to do four people, but I don’t know those right now. [Laughter]

Host: Now what about the, when it comes to if you were to look at the Apollo command module and the Orion, and then the service modules of each. Now what are we looking at in terms of design, in terms of size, in terms of technology differences between these vehicles?

Nujoud Merancy: So Apollo had, what we say with those three people, a very small command module and a really big service module, because they were getting all of those lunar orbit insertion and departure burns from the service module. Orion has a bigger crew module, so they call it command module, we call it crew module, there’s the big difference, so our crew module is much bigger than Apollo, but we have a little bit smaller of a service module and we were sized a little bit different a long time ago, so we have less Delta V capability in Orion, but we’re also carrying more people. So the bigger mass you have, the you know, how much mass you have F equals MA, more fuel you need just to push that around. So a lot of the fuel is going to pushing around that bigger crew module on Orion. And then one of the other big differences, we talked about the fuel cells earlier, Orion has solar arrays and the real reason for that is because then you can do long duration missions because you get free power from the sun for as long as you want to be there. So Orion doesn’t have, you know, Apollo had a 14 day limit on the vehicle with the fuel cells, but Orion, for power, can fly unlimited.

Host: OK. There’s also differences between what we just described in the Apollo mission going right to low lunar orbit, versus Artemis going to this Near Rectilinear Halo Orbit, what are the constraints for each of those?

Nujoud Merancy: So, it’s really about that timing with the arrival at Gateway and it’s how much Delta Velocity you can produce with your service module. So Orion is going to NRHO and can take a logistics module and meet up with Gateway, it’s really a sweet spot up in orbit because you don’t need any gas to stay there. Or at least you need very little. So as you were talking earlier, you have to maintain your precision orbit and know where you are, but when you’re in Near Rectilinear Halo Orbit, sort of the Moon and the Earth’s gravity do it for you. So you just store or stay in this nice happy place. So there’s a reason if you put the Gateway there, now the Gateway doesn’t have to carry a lot of prop just to stay in orbit. So you have this orbit that’s good for hundreds of years, with very little prop to stay there, so that’s a, it’s a really nice balance point between the Earth and the Moon.

Host: Because the mission profile of Artemis is to be there longer whereas Apollo was just, and you’re even describing it in just launching and all these different communications constraints, they just had, they had to work with what they had, technology wise, and communications wise, this is just like we can narrow it down to where we want to land to like this spot, and you said that you had to cancel out like 80% of the Moon whenever you’re considering where to land with Apollo.

Nujoud Merancy: Yeah, and so Apollo, since they used that low lunar orbit, they have to keep using gas to counteract the procession of the orbit, so you can keep aligned with the lander and with Earth to come home again, so you can’t do that indefinitely or you’d need an enormous amount of fuel to do that, so if you want to do longer missions, you need to be able to get back to your staging orbit continuously without spending tons of prop. And so that’s the real advantage of a Near Rectilinear Halo, is you have that long duration orbit that doesn’t need fuel to keep moving it around the Moon.

Host: Now with Apollo, you know, we talked about the very limited selection of landing zones that they could choose, but even then there was constraints with landing zones. I know just the performance of the command module, the terrain of what you actually had to do because you had to look for that nice flat spot with limited obstruction, but even lighting was a big concern.

Nujoud Merancy: Yeah, one of the most fascinating things about Apollo, I mean they’re using the technology they had during the day, but you had to do manual piloting to land, which means the crew had to look at the surface, they had some guidance to point them, but the crew was doing terrain awareness, the hazard avoidance, they literally were using a joystick to fly it down and when, to do that, now you need to be able to see the obstructions and things like that, and because the Moon is all very gray, with a highly reflective surface, if you come in with the sun overhead, it washes out a lot of the features. So you had to land, they only had a landing zone with the light had to be within 13 and 26 degrees, the sun had to be 13 to 26 degrees off the surface of the Moon in order for the crew to be able to see all of the rocks and craters to avoid. So with that, each landing site on the Moon is only available one day a month.

Host: Oh my God.

Nujoud Merancy: So the sun, the Moon keeps turning, it goes around the sun, right? And so each landing site on the Moon, the sun is only on the right place one day a month, so if you wanted to go to a specific place on the equator, you could only launch once a month to get to it.

Host: Wow.

Nujoud Merancy: And so, for Apollo, they could launch a couple times a month, but they were literally, if they had missed one launch, they’d go land at a completely different place on the Moon. So if you were going to try to build a base, it’s not a very useful operation to build up something because you can only get there once a month or you have to pick a different place. And if you’re building a base, you need to go back to the same place over and over again.

Host: Wow. So what changes with Artemis, how are we able to I guess have the flexibility and not be constrained by lighting?

Nujoud Merancy: So this is where advanced technology again comes into play. So for landing on Artemis, now we have flash LIDAR’s, we have lots of sensor technology, optical cameras with software behind them, so you can use LIDAR’s and cameras to do that terrain and hazard avoidance. So now the crew’s eyes can be there for safety, but you’re really going to rely on that technology because when you’re on the South Pole of the Moon, the sun is only about zero to 10 degrees off the surface of the Moon. So it’s like just coming right over the edge of the horizon, and if you’ve got a tall mountain in the way, you can actually be shadowed by a mountain in the distance. So, all on that South Pole, you’ve got to, you can’t rely on the sun and the crew’s eyes so well, because they may not be able to tell what all the hazards are.

Host: Now, the landing itself, I mean if we’re talking technology, all of these different cameras that can actually help you with that lighting, I’m assuming even the landing itself, you have, you can be more precise, you could be more accurate with that landing.

Nujoud Merancy: Much more precise, right? With our advanced navigation and the electronics of the flash LIDAR, will be able to target a much more precise landing and if you start, you know, looking out into the future, you can always land beacons and things like that, and now you can fly to beacons so if you robotically land a beacon, now you can have even more precise landing, because basically you need to create a GPS around the Moon. [Laughter]

Host: That’s right! So yeah, all these, all these technologies that can help you with an Artemis landing on the Moon, now returning to Earth, what were the constraints for Apollo with, we already kind of went through some of the different things with, you have this wider area that’s in the middle of the Pacific Ocean, but I know one of the more interesting things that I read was this weather decision point. Because if you know, you have this big wide area, but if weather’s bad, you’re not landing there.

Nujoud Merancy: Right, for both Apollo and Artemis, you have the same constraint. When you targeted where you’re landing in the ocean, you did that when you left the Moon, which was five days ago. And there’s a lot that can happen in the weather in five days, so as you’re coming back to Earth, for both of them, about a day before you get into the Earth’s atmosphere, you have a choice to do a burn, to change where you target. So Apollo could move it about 1000 miles up range, and same with Orion, Orion can move it up to 1200 miles up range, so if there’s you know, a hurricane, that’s suddenly clogged your landing site, you need to move it away and the Navy will have to move their ships to get there so you can land away from the weather system. And so Orion using that skip entry and some retargeting, you can move it more than Apollo could. So you have a little bit of advantage there.

Host: Little bit of advantage. And then the other one, referring to lighting, one of the things I saw for Artemis, is that it is, I like this term, lighting agnostic. [Laughter]

Host: Yeah, so Apollo, you had to land in the daylight because they had to be able to see it, they put helicopters out there, they didn’t have you know, night vision goggles, things like that, so you really, you had to land in the daylight, which is another big constraint on when you could go to the Moon, because first you needed your Moon to have lighting and then you need the ocean to have lighting when they come home. So that also narrows down how much of the month you can launch in. For Artemis, because we’re dealing with rendezvouses, we want to go to the South Pole, which has a lot of constraints, we’re really challenging the recovery teams to come up with a solution to land independent of lighting. So, using their advanced technology again, let’s find a way to make sure that we aren’t constrained to a night landing, or a daylight landing I should say.

Host: Yeah, and it’s just, you kind of take it for granted, whenever you’re watching the, like if you watch historical Apollo mission, you’re like oh, look at that, they picked them up. And you don’t even realize like, they had to pick that specific time, because they needed to have the lighting and they needed to pick that exact location because of the lighting, because of the communications, it’s just all of these different plans have to come together perfectly to execute this mission, but it’s like you don’t even realize it.

Nujoud Merancy: Yeah, mission planning, it’s sort of a hidden thing, right? You know you just sort of watch it and it’s like of course it worked. But before you can launch it, you’ve got to make sure every piece and all the pieces are going to come together and everyone’s doing their part. It’s like party planning, right? You know, everyone needs to show up at the right time, with the right things.

Host: Now the programmatic differences between Apollo and Artemis, you kind of went over this a little bit for Apollo, it was national contractors, it was something called One Mission Unique?

Nujoud Merancy: Yeah, so they didn’t reuse any hardware. It was you know, where you build it up, you fly it, you throw it all away, you land it again, and you’re done. We don’t have a lot of reusability in our program, but it’s a lot of evolve ability, so we can actually move on Orion upgrades, the Gateway can add components over time, the lander can be upgraded, so how do you position these things and then, it’s also looking Mars forward. So what you do on the Gateway, is basically demonstrating what you need for Mars vehicles in the future. So how do you demonstrate things in lunar orbit, the landers are very similar to what you’re going to need on Mars, so what can we do now, around the Moon, to evolve into those long duration Mars vehicles?

Host: And then, for Apollo, you had to do it, I want to say by yourself, I mean you had national help, but it was a U.S. effort, Artemis, international.

Nujoud Merancy: Artemis and Artemis is very much intended to be international, and it already is international because the European Space Agency builds the majority of the service module on Orion, so we already have partnerships going and of course there’s lots of working groups with the international community about how do they partner In Artemis going forward; whether that’s equipment on the surface, equipment on Gateway, modules, things like that, so those discussions go on all the time and I’m very looking forward to seeing our international partners help us out.

Host: Very much so. And we have history to pull from, right? We have the Apollo Program, we did it, we landed on the Moon, it was amazing, and now we can take that knowledge and use it for Artemis. The difference with Apollo was like, and we mentioned this a million times, they had to build that from the ground up.

Nujoud Merancy: Right, a lot of those things from Apollo, we’re really reusing them, I mean the vehicle assembly building, that very famous, enormous building at Kennedy Space Center, was built for Apollo. It stacked the shuttle, it launched all of the U.S. elements to the space station, and now it’s going to stack SLS and Orion. So, even some of those features we have from Apollo, are still around helping us out today, and then a lot of the things, the physics didn’t change. So how you design a trajectory to the Moon, a lot of that math is exactly the same, and we’re just using it differently.

Host: Yeah, so, kind of to sum up, we’ve explored a lot of the differences, Apollo vs.Artemis, why is it important to do it this way? To do Artemis to be sustainable, to have this sort of flexibility? Why is that important?

Nujoud Merancy: I think it’s important and my personal perspective, right? Is to be flexible and evolvable. So you know, we did Apollo, they put the boot prints on the Moon, it was very expensive program in 1960’s dollars, in 1970’s dollars, and it was, but it could only accomplice so much. So now, in order to be sustainable, and evolvable, we have to sort of break things up into more pieces. You need to spread out the partnerships, but all of this is so that we can keep exploring. I hope we don’t go to the Moon, say we did it again, and then stop going for another 50 years. I hope once we fly Artemis 3, that’s just the first of many flights to the Moon and then Mars.

Host: Yeah, that’s actually one of the things I remember the administrator saying was, one of the problems of Apollo was that it stopped. Right? We want to continue this. But I think it’s important to not understate the value of Apollo. It was a life-changing program. It was, I mean, it redefined what was possible for humans.

Nujoud Merancy: Absolutely, it really set the standard for any program, that if you’re going to achieve a lot in a very short time, you can’t look at any other program in human history without look at all the technological advancements they had to accomplish just to pull that off. And now we’re leveraging those to our benefit today and that’s where the new technologies we can inject just makes it that much better.

Host: So, we’ve already alluded to this a little bit, but what are some of the exciting things we can look forward to for Artemis? We already talked about Artemis 1, 2, 3. What are we looking forward to?

Nujoud Merancy: So the next big exciting thing is going to be Artemis 1, and that’ll be the launch of space launch system and Orion, hopefully just about a year from now, late 2020, and that’s going to be 26-40 days long, it’s going to send an un-crewed Orion around the Moon, so we’re going to the Moon, and we’re going soon. That will be without crew but then Artemis 2 will be the first flight of people beyond Low Earth orbit in over 50 years. So we’ve got a lot going on and we’re very close to seeing these things happen.

Host: So one of the things I like to ask a lot of guests is, because this is the Johnson Space Center, because it is, we deal a lot with human space flight, why is it important to explore space with humans?

Nujoud Merancy: I think when you send the humans; you can give the science answer, right? Humans are smarter than computers, they can see the rock they need to pick up, you can do much more effective science very quickly with humans, but the big advantage to sending the humans is hope and belief, right? When we send humans, we believe in ourselves, and that’s the value of human exploration, is it’s actually, it’s for us here on earth to believe in a little bit more, to believe we can do it when we go together.

Host: That is beautiful. Nujoud Merancy, thank you so much for coming back on Houston we have a Podcast, pleasure to have you.

Nujoud Merancy: So glad to be here again.

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Host: Hey, thanks for sticking around. Really good conversation today with Nujoud Merancy about everything Apollo Versus Artemis. If you want to know more about this Artemis program we have a great website, I hope you can memorize it. NASA.gov/Artemis. If you like podcasts we have a lot of them, there’s a lot on Houston We Have a Podcast, but we have a great selection all across NASA.gov that you can choose from. One location you can go to for all of them NASA.gov/Podcasts. If you want to talk to us, for Houston We Have a Podcast, we’re on the NASA Johnson Space Center accounts of Facebook, Twitter and Instagram. Use the hashtag #askNASA on your favorite platform to submit an idea for the show, and just make sure to mention it is for Houston We Have a Podcast. Just like the topic today, it was submitted by Lori on Twitter. Thanks, Lori. This episode was recorded on September 26, 2019. Thanks to Alex Perryman, Pat Ryan, Norah Moran, Belinda Pulido, Laura Rochon, Rachel Kraft, and Kelly Humphries. Thanks again to Nujoud Merancy for taking the time to come on the show. We’ll be back next week.