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 280, hear from a spacesuit systems engineer who explains what will be needed in the design and operation of a spacesuit on the Red Planet. This is the tenth episode in a reboot of our series about a human mission to Mars. This episode was recorded on January 20, 2021.
Gary Jordan (Host): Houston, we have a podcast! Welcome to the official podcast of the NASA Johnson Space Center, Episode 280, “Suit Up for Mars.” I’m Gary Jordan, and I’ll be your host today. On this podcast we bring in the experts, scientists, engineers, and astronauts, all to let you know what’s going on in the world of human spaceflight. We’re continuing with a reboot of our series that outlines a human mission to and from the Red Planet. The tenth episode explains what needs to be considered in the design and operation of a spacesuit that will be used to explore the surface of the Red Planet. This episode was recorded on January 20, 2021. Let’s get started.
(Transition to original episode)
There’s a lot that Mars will throw at humans exploring its surface, so we have to be prepared with the right spacesuit. Luckily, we have a lot of smart people already thinking about how to address some of these issues, things like those dust storms, mobility, and planetary protection. One of those smart people is Natalie Mary, a systems engineer for the extravehicular activity, or EVA, office. It’s her job to perform analysis and integration for the exploration EVA system with suit engineers and stakeholders from programs such as Artemis, Gateway, and Mars. So, let’s get right into it. Suiting up for Mars with Natalie Mary; enjoy.
Host:Natalie Mary, thanks for coming on Houston We Have a Podcast today.
Natalie Mary:Thanks for having me.
Host: What an interesting topic, Martian spacesuits, suiting up for working on the surface of another planet — it’s a huge deal. Natalie, I want to start with just understanding what it takes to work in such an interesting field. How do you get to the point where you are, where you’re thinking about how to live and work on Mars in a spacesuit?
Natalie Mary:Yeah, well, like most space nerds out there, I grew up looking at the sky and stars and imagining about exploration. And I mean, as a kid, I put together those little glow-in-the-dark constellations on my ceiling in my room. And I found I was decent at math and science and decided to want, you know, go into engineering, like sort of engineering field. And so I went to Texas A&M for a bachelor’s in aerospace engineering. About the time I graduated in 2000, it was perfect as NASA was hiring flight controllers, so, pretty much as the ISS assembly began. So, I was a flight controller for about eight years, and I was very privileged to be a part of that. And then after that I took on more of a like systems engineering kind of role and began working with the extravehicular activity office. And so my focus has been on systems engineering such as architecture, interfaces, OpsCons (operations concepts) for multiple missions including, exploration spacesuit capabilities for lunar, cislunar and Mars missions. And so my role has really been mainly on the architecture side of things, but to know that you need to know what folks want the suit to actually do on the surface of Mars: how the environment of Mars affects the design of the suit, what kind of architectures the suit interfaces with, like pressurized rovers or habitats. And so that is what I’m doing currently. And by the way, it’s kind of cool that you call this podcast “Suit Up for Mars,” because we have a public website that you can go to at NASA.gov/suitup, and that has our Artemis generation spacesuits rollout, some really cool references and images, and we have a yearly EVA technology workshop that includes the presentations throughout the years for that.
Host:Nice. So if you want to know more about just spacesuits in general, that’s a good place to go. So, Natalie, why don’t we start with that: spacesuits in general. Give folks a sneak peek on what’s on that website, and sort of what we’re going to be talking about today. So, some of those things you’ve got to consider when you’re designing a spacesuit: what are the things that are, that a spacesuit provides that is, it’s necessary for space exploration?
Natalie Mary:Yeah, yeah. So the spacesuit provides the crew member with the life support, environmental protection, and communications capability to allow EVAs outside of the vehicle, extravehicular activity outside of the vehicle in the vacuum of space or on a planetary surface. So, it’s not just clothes or scuba diving equipment, for example, like if you’re going to go scuba diving you have your dive suit for thermal, your buoyancy control, masks and breathing air, dive computer, things like that. But with a spacesuit, that includes thermal protection and mobility and informatics, but it also protects you from vacuum by providing a pressure garment and oxygen and CO2 (carbon dioxide) removal, communications, power, cooling water, drinking water, and waste management. All the things that you need to survive. And so, it’s pretty much your own personal spacecraft.
Host:That’s actually the best way that I’ve ever heard it being described, is your own personal spacecraft or like, a spacecraft shaped like a human body. That’s, that’s essentially what it is, is doing all these things to, you know, separate all the needs, or to give all the needs of what the human body is wanting within that environment, because space or other planets, they just don’t provide those needs, right?
Host:Yeah. Now, there’s a couple of things about, you know, spacesuits; you mentioned a couple when you were talking about your current work on, thinking about what suit is going to be needed for Mars, and some of the things you brought up was, like, the architecture of, of Mars itself, right, what’s going to be on the surface that the suit is going to need to interact with? What are you going to be doing? What do you want to do? I think, like, bending up and picking up rocks is probably one of those things you want to do. And some of the environment. So, you know, I’m thinking about those things, but I wanted to stay with just spacesuits in general, right? So, like, thinking about, you know, how a spacesuit is designed to, to meet needs, right, so you’re talking about the needs of a planet. Let’s back up to, like, the EMU (Extravehicular Mobility Unit), right, this is the suit that’s on the International Space Station. It’s meant for microgravity. What purposes is the EMU, what is the EMU addressing, you know, what is it, how is it designed to operate the most efficiently in a microgravity environment?
Natalie Mary:OK, so transitioning from a suit made for microgravity to reduced gravity, there’s definitely some differences in mobility. So, in microgravity, you’re really transitioning and translating with your arms and hands, and your boots and your legs are pretty much stable or floating, I guess, per se. But for the Moon and Mars, reduced gravity will need that capability in the lower torso, waist, legs, boots to walk on the surface, kneel down and pick something up, and explore on uneven terrain. The EMU was designed for microgravity, so it doesn’t have those bearings in the lower torso or hiking-style boots designed for walking. And then the life support for microgravity and vacuum is also different. It’s designed for vacuum, and it, and the EMU it’s a great system, it’s called METOX (metal oxide), but it, it uses a heavy oven, an airlock, to kind of bake off that CO2 for CO2 removal. And the suit mass itself is designed, it’s not that big of a deal for microgravity, but it becomes pretty important when you start talking about the mass worn by the crew member on Mars and on the Moon. The EMU is also, it wasn’t designed to be repaired and remove and replace components on orbit. It was, it has the ability with ISS to be able to bring back the entire suit and fix things on Earth. And with Mars and the Moon, that’s, we’re looking at being able to repair components or remove and replace components in situ.
Host:Oh, see, that’s a big deal, right, because you, that’s kind of a, it’s a much different of a trip to go from low-Earth orbit back to Earth than it is, than it is from Mars. I’m thinking about the features of the suit itself, right, things that you need; I think you have a great description of just what it’s providing. I think another interesting component here is atmospheric pressure, right? So, we’re, we’re used to, I think, sea level is like 14.7 psi, pounds per square inch, on, on the Earth and that is matched within the environment of the International Space Station. Now, I know that suits are a little bit different. They go lower. And I’m curious as to, as to why?
Natalie Mary:Yeah, OK. So, if you were to have a suit at our sea level atmosphere, at 14.7 delta pressure to vacuum, it would pretty much blow up like a balloon and it would be really stiff, so that you could barely move your joints let alone your fingers. So during an EVA, the suit pressure is actually lowered to around 4.3 psid (pounds per square inch differential), and to do that you increase the oxygen content to 100% oxygen to both allow for improved mobility and to prevent decompression sickness, or what you call “the bends,” you usually hear it called during scuba diving. And so you can actually change the atmosphere in the vehicle, too, prior to an EVA, to reduce that duration of pre-breathe, but when you reduce the pressure you have to increase your oxygen concentration. That also increases flammability risks, and so there is actually some testing going on, it’s pretty exciting, this year to help come up with those kind of exploration atmospheres to use across vehicles from like cislunar to the Moon to Mars, and come up with some commonality in the ECLSS (Environmental Control and Life Support System) systems.
Host:Oh, that’s pretty cool. Just like a, like a guide for if you’re working here, this is the atmospheric pressure you want. Maybe, maybe about composition, too. So, that’s what you’re doing, you’re making almost a guidebook for depending on where you’re exploring.
Natalie Mary:Exactly, yeah. And that’ll help with probably coming up with the objectives of a mission or the particular science objective and what you want to do during an EVA, how often you want to go EVA, and that duration. So those different atmospheres will affect that, that time that you prepare for an EVA.
Host:Cool. So, we’re talking about atmospheric pressures and, Natalie, you went through a lot of the components of, you know, what’s on the suits that we know, these microgravity suits, right, the oxygen, waste management, power. Really, what we’re leading up to here is talking about this next generations of suits.
Natalie Mary:OK, yeah, these are really exciting times to be working with the EVA community, because we’ve already incorporated a lot of things and lessons learned from past spacesuits and 50 years of EVAs. And so, one of the major things, I think, are incorporating the increased upper mobility and lower mobility to allow those crew members to perform the science that they want and go exploring. And so, I had the pleasure of going on a geology field trip with our awesome geologists, and it was amazing. And while you plan a traverse prior to going into the field, you end up finding interesting rocks or transitional regions that just make you want to go climb into the rocks and, or dig and collect samples. For instance, the scientists want to be able to go into a permanently shadowed crater or region and collect samples or climb on some uneven terrain. And so, we’ve incorporated that mobility by including hip and leg bearings so that you can rotate and bend and get down and onto your knee and collect a sample. And so the upper torso has also been made with greater mobility in mind, not only for the smaller crew members but also being able to rotate the shoulders, and those side bearings have been moved closer in so that you can reach over and touch, you know, your shoulder. And so, that’s a really, those are really interesting for lunar and Mars surfaces that we can learn from even further.
Host: So, the discussions we’re having now is, like, mobility, right, so, you got that lower mobility, you got the upper mobility; the things you are considering is what are we going to be doing on the surface? And that’s going to inform design. So, obviously, you know, having more ability – mobility, rather — on the lower torso to bend over and on the upper torso to grab rocks and climb stuff, the suit port has to serve a purpose for what you’re going to be doing on the surface, right? So, how does that come into play? Why is that necessary for when you’re operating on the Moon?
Natalie Mary:OK, yeah, so suit ports are a technology that you may have seen on the pressurized rover pics or even here on site at JSC in Building 9 [Space Vehicle Mockup Facility]. But we’re considering it within the range of technology options being evaluated for our suit technology, and, which is flexible enough to support it, given those things that I just mentioned. And so, being able to don the suit through the back hatch, the suit has that capability, as well as the capability of a variable pressure regulator so that you can start at a different or higher pressure differential. This could allow the crew member, depending on what starting pressure they’re saturated at, to be able to have a shorter pre-breathe, ingress the suit through that hatch, and hop off the vehicle, basically. So, it, it could decrease that pre-EVA time quite a bit. And so there’s a lot of discussion on if you want to jump out and look at something interesting or if you want to stay out for longer, basically you could have that capability of doing both. You would be able to plan your traverses and have the capability to perform a longer EVA; if you’re out for a long time and want to perform science at a specific site, or have that cycle capability if you want to perform multiple EVAs in a day.
Host:So, let’s continue down that path, Natalie, about exploring the, the operations of, of performing an EVA on the surface. Take us through what that’s going to be like. You already mentioned, you know, entering through the back port of the suit, and doing a pre-breathe operations, but what’s, what’s a, what’s an excursion going to look like? Let’s start with the Moon: what would an excursion look like on the Moon?
Natalie Mary:Yeah, so, we have some operational concepts that we’re looking at. If you have a habitat, say, and a pressurized rover, you’re looking at going out on excursions in the pressurized rover, away from the habitat for maybe a week or two at a time, and kind of doing maybe a cloverleaf-type traverse. Kind of going out farther and then coming back in to the locations that scientists want to go perform their objectives. And so, maybe during a day you’d go out in, in your pressurized rover, and then your pre-breathe, you’re already saturated at that, that pressure, and so you’re able to get in your suit, perform suit checkout, egress the suit port and perform your science objective. Possibly come back in for lunch or potty break, or something like that, and then go back out. Or you could go out for even longer – eight-hour duration EVA and come back in. And eventually we’re going to need to perform suit maintenance on the suits. And so to do that, we’re going to be using a pressurizable volume and bringing the suits inside a pressurizable volume like an airlock on the habitat. So eventually you’d go back to that habitat and bring the suits inside an airlock for suit maintenance.
Host:Oh, interesting. OK. So, yeah, you would have that ability. So, I guess the suit can, yeah, would have to be in that airlock so you can regularly work on it. The maintenance that you’re doing would be like, you know, switching out internal components, maybe, are we talking, maybe, gloves? What do you mean by maintenance?
Natalie Mary:Yeah, so we do have experience with ISS, you’ve got an engineered, smooth surface except for a micrometeorite, so we do have some debris that will hit handrails and things like that. So there are sharp edges on the ISS, so we have experience with that. But what we don’t have as much experience with is, you know, the sharp, dusty environment of the Moon, or the dusty environment of Mars. And so we know just from ISS that we need to change out the gloves fairly frequently. So that’s something that, an example of some suit maintenance that we would need to do on the surface. And then there’s other components that we, maybe, are called limited-life items, things that we know we’ll need to replace after a certain amount of cycle life. And so that’s when we would bring the suit inside for suit maintenance. But that is, actually, another way we’re going to be using the Moon as an analog to Mars, is understanding further those operations of the pressurized rover, suit maintainability, and suit reliability. So those things we might be able to decrease in time, the more we know about the suit, and what is, what the main components and sparing philosophy will be for the Moon and Mars.
Host:Oh, interesting, yeah. That makes a lot of sense, right? Moon, that’s part of the Artemis program, going to, returning to the surface of the Moon and performing those operations. A lot of the stuff that you’re doing there, the operations that you’re talking about, having, you know, the design of how you’re going to be performing an EVA and then how you maintain the suits and everything, that’s really good, really good analog, really good practice for when you ultimately end up at the surface of Mars.
Natalie Mary:Exactly, yeah. It’s just, it’s another steppingstone and what we call or refer to as an analog for Mars. And while there are differences and challenges between the Moon and Mars that we will need further technology development with, there’s a lot of similarities there that we’ll learn from on the Moon.
Host:Well, let’s go into understanding a little bit about Mars, what Mars is going to throw at us when we actually get there on the surface and start working in spacesuits. So, what is it about Mars, you know, what is it about the Mars environment that you are preparing for and that you are putting into the design of a spacesuit?
Natalie Mary:Yeah, OK. So, Mars does have, you know, an atmosphere, albeit a small one. But there’s actually wind and fine particles that will get on the suit. It’s also dusty like the Moon; hopefully less sharp dust because of the atmosphere. But the lunar surface will get us a lot closer to understanding kind of like a layered engineering protocol to design the suits for removal of dust outside of the habitable volume and removal and cleaning of dust inside the habitat. And this will become really important on Mars, too, because of planetary protection. So, there’s a committee on space research that classifies the Moon and Mars differently. And we’ll likely have to abide by more stringent planetary protection protocols on Mars than we do on ISS and the Moon. And so that means protecting Mars science from human contaminants, or forward contamination, and protecting the humans from anything that might be harmful on Mars, or backward contamination. So, the suit ports could also there be an important process of preventing that backward contamination by what is referred to as breaking the chain or leaving the dusty suits behind on the surface of Mars. And with that, though, with the suit port design, it also does have impacts on, or changes that would need to be made from an initial xEMU (Exploration Extravehicular Mobility Units) to a Mars suit. And so, it can add mass to the suit, because it has to add a suit port interface plate that actually is a sealing surface between the suit and the bulkhead of the pressurized rover. So one of the things we’re really going to be looking forward to is the technology development of that, but the technology development of how we can reduce the mass on the suit for Mars. So that gets really important when you’re talking about getting down to Mars surface after being in microgravity for so long, getting to that 3/8 gravity as opposed to what we’ve learned from the Moon’s 1/6 gravity. And so with the crew members having been in space for six to nine months, they’ve really gotten acclimated to microgravity. So when you get to the surface you really don’t want to battle a heavy suit with a very different, or possibly different, CG (center of gravity) after being in microgravity, and then getting down to the surface. And so I know doctors are saying that they will need to acclimate to that higher gravity over a certain amount of time, and so we’ll stay in the vehicle for a little bit longer, possibly, before performing an EVA. But that mass reduction and understanding CG will be a big deal for crew members acclimating to the Martian gravity.
Host:So, now we’re talking about taking this, what we’re thinking about for the xEMU, right, this is the one we’re thinking about for the surface of the Mars, you’re talking about taking a step further. What technologies are needed to take that step to eventually work on the surface of Mars? Mass reduction is one of those things; what else, what else are we thinking about that, some technology we need to develop for, for getting ready for working on Mars?
Natalie Mary:OK, yeah. We definitely know we have some upgrades that we need to do…
Natalie Mary:…to develop a suit for Mars. And so materials is one of those things as well. We’re looking, we’re actually going to have some materials on, landing on Mars pretty soon, on the Perseverance rover. I think that’s…
Natalie Mary:…yeah, yeah. I think that’s February 18, right? So, it’ll be carrying a payload called SHERLOC (Scanning Habitable Environments with Raman & Luminescence for Organics & Chemicals), which includes materials from the visor and pressure garment system to see how well they hold up to the radiation on Mars over time. And some other technologies are, like we mentioned, the atmosphere on Mars is more of a CO2 atmosphere. And then the thermal environment is different. So, those are two, sometimes what we call gaps that we’re looking forward in our strategic planning on technologies that we can upgrade for Mars. So, our xEMU technology is awesome and it’s really more efficient for vacuum, though; it uses a swingbed technology. And so that CO2 is collected on one side of the bed, and then once it’s flipped it is vented to vacuum. But with a CO2 atmosphere on Mars, an upgrade will be necessary. And so, the same thing goes with the cooling swingbeds, and the fact that Mars has more of a convective thermal atmosphere with weather and seasons than a radiator like the vacuum of space and lunar surface. So, we’ll be looking at different technologies for CO2 removal and thermal cooling and heating. And another change is going to be that comm[unication] delay between Earth and Mars, right? It could be, I think we were talking up to 22 minutes one way. And so we rely a lot on the MCC — Mission Control Center — to provide guidance and monitor data and send commands right now for ISS, and also for Mars. I mean for Moon. But for Mars, crew autonomy is going to be, become a lot more important. More important than ever, with crew members possibly consisting of scientists, and then greater reliance on software and procedures on the suit, and maybe intravehicular crew member guidance, like your crew members that are on, on Mars with you. And so that communication is going to become really important, and autonomy.
Host:See, that’s that wouldn’t even be something that I would think of immediately, you know? And I, I actually do commentary for spacewalks now, and you can just hear over the loops, just all the behind-the-scenes work, all the behind-the-scenes chatter that’s happening as we’re watching a spacewalk happen real time. There’s decisions being made and people analyzing data from all these different angles, so it’s just, it’s really, just understanding that from my perspective and being a part of that, thinking about all of that goes away, right, all of those helping hands, all those eyeballs go away, because there’s no way to efficiently conduct a spacewalk with, you’re waiting 22 minutes, even more, more than that, for an answer, if you have a question. Very interesting stuff. Is there thoughts to practice this, you know, whether it’s on the Moon or otherwise, just to sort of get used to it before we do it for real?
Natalie Mary:Yeah, we actually do a lot of analog work in 1 g on this. And even incorporating in delays in comm[unication]. And then, I think that’s a great analog for the Moon is once we start upgrading our informatic systems and even allowing the crew members during an EVA to change procedures or make decisions based on the science that they see right in front of their face, then that’s a really good analog to use the Moon as, as well.
Host:Well, Natalie, I’m super-excited about Mars. And it just sounds like there’s a lot of challenges ahead to, to take that next step, and close those gaps, as you were saying, right? There’s just a lot of work ahead. But I’m thinking about the near future. I’m thinking about Artemis and how, how near-term that seems to us right now, you know? Going on the surface of the Moon and working and doing great science and everything. I’m curious from your perspective working on spacesuits, I’m curious to hear what you are excited for, for this upcoming period of time where we’re going to have a new generation of moonwalkers, and what you’re looking forward to doing and exploring that’s going to help you in your job in understanding how to live and work on Mars in spacesuits.
Natalie Mary:Oh, yeah, I’m super-excited. This is an awesome time to be working in the EVA community and lunar surface and Artemis. And so, yeah, Artemis just offers great opportunity to test out our systems and operations closer to home and understand that maintenance and reliability and the operations and crew autonomy. And so even though some of those aspects of our Mars suit are different than the Artemis lunar suit, there’s just so many of the operations — like dust removal is a big thing, and in situ suit maintenance — and so I think those are going to be an amazing analog to, to go for Mars.
Host:Very cool. Natalie, this has been really, really, really interesting to dive so deep into, you know, not even this next generation of suits, but it’s cool to hear that, that there’s a team of really smart people thinking about the generation after that, right? Just getting us ready to take those next steps. So it was really a pleasure to talk to you about and dive deep into all the fascinating aspects of the Martian spacesuit. I appreciate your time, Natalie.
Natalie Mary:Thank you.
Host: Hey, thanks for sticking around. Hope you’re enjoying our reboot of the Mars series. You can skip ahead to the final episode, if you want, at NASA.gov/podcasts and check out any of our episodes in no particular order, but there’s especially a Mars collection of episodes and you can check out the last one if you want. If not, don’t worry about it, we’re going to bring right to your feed next week. While you’re there at NASA.gov/podcasts, make sure you check out some of the other great shows we have across the whole agency. If you want to talk to us specifically, you can talk to us at the NASA Johnson Space Center pages of Facebook, Twitter, and Instagram. You can use the hashtag #AskNASA on any of those platforms to submit an idea for the show, maybe ask a question, just make sure to mention it’s for us at Houston We Have a Podcast. Thanks to Will Flato, Pat Ryan, Heidi Lavelle, Belinda Pulido, and Jaden Jennings for their part in this podcast as always; shoutout to former podcast team members Alex Perryman, Norah Moran, and Jennifer Hernandez for their help in the original episode. The episode originally aired February 5, 2021, as Episode 181. Thanks again to Natalie Mary for taking the time to come on the show. Next week for Episode 11, the final episode in our Mars series, we chat with NASA’s Mars architecture team about the mechanics of returning the first astronauts from the surface of Mars back home to Earth. Give us a rating and feedback on whatever platform you’re listening to us on and tell us how we did. We’ll be back next week.