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 242, Pamela Clark and Cliff Brambora describe a satellite to be deployed on the Artemis I mission that may better map lunar ices. This episode was recorded on March 14, 2022.
Transcript
Gary Jordan (Host): Houston, we have a podcast! Welcome to the official podcast of the NASA Johnson Space Center, Episode 242, “Mapping Lunar Ice.” I’m Gary Jordan, I’ll be your host today. On this podcast, we bring in the experts, scientists, engineers, and astronauts, all to let you know what’s going on in the world of human spaceflight. As we continue to talk about returning humans to the Moon as part of NASA’s Artemis missions, it’s essential to gather as much data about the lunar surface ahead of the boot prints. We know that there is water ice on the Moon, and we have a rough idea of where it is, but there’s one experiment coming up on the Artemis I mission that’s going to give us an even better understanding. On this episode we’re talking about a shoebox-size satellite that will help us understand, and even map, water ice on the Moon. To explain a little more about Lunar Ice Cube, the name of the mission, we have previous Principal Investigator Dr. Pamela Clark, director of Morehead State’s Star Theater, and a space systems engineering instructor at Morehead State University; and we have Cliff Brambora, BIRCHES (Broadband InfraRed Compact High Resolution Exploration Spectrometer) lead engineer from the NASA Goddard Space Flight Center. Yes, we get into what BIRCHES is. So let’s get right into it. Enjoy.
[Music]
Host: Pamela and Cliff, thank you so much for coming on Houston We Have a Podcast today.
Pamela Clark: Thanks so much for giving us the opportunity to talk about Lunar Ice Cube.
Clifford Brambora: Yes, thank you, it’s very nice to have this opportunity.
Host: Very good to have you both. We’re talking the science, we’re talking some of the hardware that’s on this awesome experiment called Lunar Ice Cubes. I wanted to start off with just figuring out what this thing is. We’ve been diving into a couple of the payloads, a couple of the experiments that are on SLS (Space Launch System) and this, this one’s pretty cool. So let’s just, let’s just start off with, right off the bat, Pamela, I’ll start with you, to help us to understand, what is Lunar Ice Cubes? What is this experiment?
Pamela Clark: So Lunar Ice Cube is a 6U CubeSat mission with a infrared spectrometer based on the OVIRS (OSIRIS-REx Visible and Infrared Spectrometer) instrument, but a much smaller version of it, which has the capability of measuring infrared reflectance from about one-to-four microns. And therefore, that is an area that contains absorption features associated with water in various forms, and components of water like hydroxyl. So we’re hoping to see the variation in absorptions due to water in the reflectance spectrum from one-to-four microns as a function of time of day, and the way we do that is as a, the, the spacecraft is put into a repeating pattern where it will go back and look at the same area on the surface at different times of day, over the course of several months. And therefore we’ll be able to look at the presence of water on the surface as a function of time of day, and that will help us to understand water distribution on the Moon.
Host: That is a big deal. Of course, let’s, let’s back up for — even more than that — you are talking about the fact that there is water on the Moon. That sounds like a pretty big deal. Can you tell us about, just what we know so far, and then what Lunar Ice Cube is, is trying to fill in the gaps for?
Pamela Clark: Right. Well, you know, the, up until maybe just over ten years ago, folks really didn’t think that there was much water on the Moon, but then there were several missions that kind of serendipitously looked at water, saw some feature associated with water as flybys. And then of course, Chandrayaan[-1] M3 (Moon Minerology Mapper) took a snapshot which looked at what could, those, at those features absorption features, and it, it seemed likely in fact, and it was, seems to be correlated with the amount of illumination and thermal conditions on the lunar surface, and the, that, and, combining that information with other information we got from LRO (Lunar Reconnaissance Orbiter), for example, which is the Goddard mission, and looking at what the temperature would be, where there could be places, where there could be cold traps for water, got people thinking about the possibility of water below the surface as well as on the surface. And of course, what we’re looking for and why it’s so important and why AES (Advanced Exploration Systems) sponsored this mission, Lunar Ice Cube, was to see if we could help to get a handle on where we would look for water, which we could use as a resource on the Moon, not only in terms of understanding — and it’s, it’s good to know from the scientific standpoint in terms of the role water may have played in the origin of the Moon, lunar regolith and other small bodies in the solar system — but also to know where there could be water deposits that could be resources that could be useful for utilization on the Moon by a human crew.
Host: Awesome. Pamela, you’re talking about the science of, of water on the Moon, and of course, you’re trying to look for it. You, you mentioned LRO, the Lunar Reconnaissance Orbiter, there’s instruments on there that are looking at the surface of the Moon. But what’s interesting about this particular mission, Lunar Ice Cube, is, is the instruments that are going to, that are going to look for the things that you and your science team are looking for. So Cliff, we’ll go over to you for a second. What instruments are on Lunar Ice Cube that’s going to help us to understand the, the presence of water on the lunar surface?
Clifford Brambora: Sure. Good question. So, there is only one primary scientific instrument on Lunar Ice Cube, and it is the BIRCHES instrument. Everything else on the spacecraft is, is all about the spacecraft being able to exist and provide power and be able to point in the right directions. So, so BIRCHES is the instrument that we developed at Goddard Space Flight Center and Morehead University did, did the spacecraft, the Lunar Ice Cube spacecraft. So BIRCHES, as Pam mentioned, is a, is a miniaturized approximation of the OVIRS instrument, which was flown on OSIRIS-REx, which is a sample return mission that went out to this asteroid called Bennu and it’s on its way back with its little sample. Pretty cool. So we got one of the detectors, one of the infrared detectors that, that was flown on, on OVIRS, there were several other candidate flight spares and we were able to get our hands on one of those spares, and incorporate that into this much smaller version of this instrument. So, so, so BIRCHES is the, is the instrument that, that we’re using to look at the, the water features in the, in the infrared missions from the Moon and that one-to-four micron range that Pam talked about. And it’s the only instrument on board this CubeSat. And it is a CubeSat, which is very important to note because that’s a, a lower cost, higher risk way of getting science out there. And we’re very happy to be involved in that.
Host: Very cool. So, so let’s, let’s explore the OSIRIS-REx for a bit. This was, this was a mission that went on out to like an, an asteroid, like you were saying. And of course, there was this instrument on board that did something on the asteroid that was very interesting for what you’re trying to accomplish here. Can you talk about the OSIRIS-REx mission and what this, and what this infrared spectrometer did that, that could be translated to this mission?
Clifford Brambora: Sure, sure, absolutely. So there were four instruments on OSIRIS-Rex, and OVIRS was one of them. And OVIRS primary reason to exist is to survey the surface of Bennu from an infrared perspective in that same one-to-four-micron range and determine an, an area of interest for them to take the sample. That’s really its sole purpose, is to stare at the survey, the, the, the surface of Bennu, and, and based on the spectral emissions pick out an area that looked like the most fertile, useful hunk of Bennu that we could bring back to the Earth and analyze. And so it, its existence was just that. And, once it did that job, it was pretty much done; said, well, this is the spot and maybe this is the backup spot and then you guys need to go get that sample. So that’s what, that’s what OVIRS was all about. And, and just as an example of size — you know, OVIRS was, was, was probably about a foot and a half by, by two and a half feet by, maybe a foot tall. And BIRCHES by comparison is about the size of a large Kleenex box. So it’s much smaller.
Host: Awesome. Well, let, let’s, let’s continue, let’s continue this discussion about Lunar Ice Cube. Let’s talk about the science. Let’s talk about the, the engineering process to miniaturize and, and create this, this BIRCHES instrument. I want, I want to fully explore what it took to get this mission together. So Pamela, let’s start with just, you know, the fact of working together, because you, you are at the Morehead State University, and of course you had to come up, were collaborating together with NASA. How did this all come together? The, the, the universities and space agencies all coming together to say, hey, let’s let, I got this great idea about — ways that we can explore water ice on, on the lunar surface; what was, how, how did this all come together?
Pamela Clark: So I started an advanced concept group at Goddard Space Flight Center when I was there, put together a team of folks from different engineering disciplines to look at the possibility of creating a 6U-contained spacecraft that could support an infrared spectrometer, which by the way is quite challenging because also requires like the cryocooler, and that takes power. And there’s that, 6U is not very much space, and particularly challenging from a thermal standpoint, because you know, getting rid of waste heat can be very challenging and the Moon is a thermally challenging environment. So one of the first things I did was to include thermal engineer as part of the team. And we looked at this concept for at least a couple of years, and I had already done proposals with Ben Malphrus at Morehead State University for CubeSat missions, mostly Earth-orbiting. And so when an opportunity came along through the NextSTEP program, sponsored by AES at NASA, to propose to do missions that could do one of several things. One was to develop instrumentation that could basically look for water on the Moon. And so we did that plus we are, we’re basically using a new CubeSat propulsion system, and the Morehead State University folks already had worked on the collaborative project with the Busek people who developed our propulsion system. And, in addition to that, after the mission was selected, I moved to JPL (Jet Propulsion Laboratory), worked at JPL for about six years, and continued to be science PI (principal investigator) while I was at JPL, before I moved to Morehead State University. So at JPL, I mean, we also had collaborations with the Deep Space Network folks. I mean, one of the things you may not know about Morehead State University is that is the only non-government official DSN station, station 17 here at Morehead. And we will be using that, among other stations, when we get, when we do uplinks and downlinks from the spacecraft during the, during the mission. So there’s a number, it is challenging to do a number of, to have a number of collaborators that are all over the country. Fortunately for us, when, during the shutdown, Morehead actually, the baseline center was actually open and continued to be able to work on the spacecraft. So that, you know, that’s a, that’s not unusual for CubeSat teams. I know something about the other Artemis deployees, all these CubeSats that will be deployed, and many of them are multi, you know, multi-institutional teams. And in fact we just had a summit to look at some of the lessons learned from, from all the various missions and are about to try to publish a paper on that. But yeah, so we, you know, we learned a lot: 6U is a very challenging size. I think if we had to do this again, and most of us would go to 12U; 6U is small, not a lot of surface area to put all the stuff we need. Getting all the, you know, getting enough surface area for the power system, being able to deal with the thermal environment involving getting rid of waste heat, and we have some pretty, you know, we have some subsystems on there that require a lot of power. The propulsion system does, the communication system does, and when we turn the cryocooler on, you know, we need to also have, you know, we need, that also requires some power, too. So I’ll let Cliff talk a little bit more about the challenges of trying to keep everything going sufficiently and being able to take the measurements. And we’ll also be doing some inflight calibrations, so that’ll also be an interesting challenge to be able to find time when that can be done when we’re not, when the propulsion system isn’t on and we’re not tracking with the communication system. So it’s, you know, CubeSat missions, especially the first generation in deep space, are really, really challenging and require a tremendous amount of cleverness to make them work. So we’ll be learning a lot when we’re operational, when we actually get to deploy from Artemis as well, but we’ve learned a lot in a lessons learned in terms of what we’ve done so far, too.
Host: Yeah. Lot, lots, lots of challenges. You’re tee, you’re teeing Cliff up here very nicely to, to, to, to dive into that. So let, so let’s go right to it. Cliff, Pamela was mentioning a number of engineering challenges. You have cooling challenges, you have size challenges, you have power challenges. How did you and your team start really tackling some of these; presented this, this really big ask, hey, we want to fit this, this fancy science instrument with all these power constraints, and it’s going to generate a lot of heat and we want to make it into a, a tiny 6U size CubeSat, how’d you, how’d you tackle that?
Clifford Brambora: OK, great question. And thanks, Pam. You’re absolutely right. And one thing that, that most people don’t necessarily realize when they go into this type of, of activity is that, that even though this is small 6U sized spacecraft, it really has all the traditional, difficult things of a larger spacecraft. Power, communication, thermal…attitude control, all these different systems, star trackers, everything exists in the same. It’s just smaller. So, so it, it’s hard, even though it’s, and it becomes even harder because its smaller. So, so we had to, we had to miniaturize this OVIRS instrument into a, a much smaller size. And we, we started with the, the, the, the optic nerve of this instrument is this, this, Teledyne detector that we, we, we got a, a spare from the OVIRS program to use, and it’s an infrared detector and it, it wants to be cold to, to do what it needs to do. In order for it to see in that one-to-four-micron area of wavelength that, that we care about, it, it really needs to be cold. So we had to, we had to put a, actively cool it with, with a what’s called a cryocooler. It’s like, picture an air conditioner, if you will, in space; it doesn’t work the same way obviously, but it it’s designed to bring heat out of that detector and get it cold. So, so that detector on, on OVIRS, it was running, at — probably somewhere in the, in the 95 Kelvin range, and that’s a great temperature for that detector to really work well. And, and we, we struggled a lot with the thermal on this, this program, getting that detector as cold as we can and, and still be able to get rid of all the waste heat in this small environment was very, very difficult. If I have to pick one thing that was the hardest, I would say it was the thermal aspects of this design. So, so we, we had to design with, with a lot of input from, a thermal engineering folks at Goddard and also at Morehead to, to figure out how we’re going to get rid of all this heat. So every, every surface on this six-sided, you know, rectangular spacecraft, rectangular-volume spacecraft, is a radiator. It, it’s designed to, to get rid of heat. So, so we had to come up with ways to, to, to bring that thermal energy to different surfaces of the spacecraft to get rid of the heat; otherwise we couldn’t get cold enough. So, so thermal was, was the biggest challenge, and then, finding very, viable ways to, to get the heat out in mostly in a, a conductive way, meaning, meaning, you know, it’s, it’s conduct through a surface, the heat energy’s flowing through metal for the most part. And then we also took advantage of what we call radiative cooling. Whereas, it’s the same reason your, your, if you have a car and it’s black, it gets hot in the Sun because it, it, the energy from the Sun is absorbed. So if you, if you take two, two boxes on a spacecraft and you, you make them black — and I’ll just say black for simplicity’s sake — that, that they’re going to talk to each other thermally and one will help cool the other. So we took advantage of that, too. And, and, and, and also an expeditious use of, of an opposite type of scenario where you put a, a, a thermal reflective material in between two things, because one thing’s hot and one thing’s cold and you want to shield it. It’s like an insulator. So we, so we used a, between radiative cooling and conductive cooling and, and, and isolating insulative type components, we were able to come up with a system that we think will, will have the detector and the internals of the instrument cold enough to be, to be of value for us. And we saw this in our thermal vac[uum] testing. It’s one of the tests you do to spacecraft systems. You should put it into a thermal vac chamber, and it simulates the conditions of space in that it sucks all the atmosphere out so you have a vacuum, and then, and then when, once the vacuum is gone, you no longer have convection. If you picture a convection oven in, in your house, it uses hot air circulating around the food item to help cook it. In space, there’s no convection, no air, you can’t talk, you can’t breathe, obviously. So this, this, this, this other way of getting heat in or out of something is gone. So, so thermal vac lets us test in, in a very space-like scenario. And during those tests we did about a year ago, we did see that we were able to get the detector down to about 128 Kelvin and see some actual results that we, we think are, indicated that the instrument was working correctly. Thermal’s definitely a challenge. One of the other things I’ll mention is the, when we’re, when we’re orbiting the Moon, the reflected Sun from the Moon — it’s called albedo energy — is, is not trivial: that the, the, the, the surface of the Moon is hot when it’s on, when it’s being hit by the Sun. And, and that energy reflects up and, and hits us. So we, we actually, you know, one of the reasons we get warm is not only because the, the Sun hitting us directly, but it’s also from the reflected energy coming up from the bottom. So that’s, primarily my long-winded point is that thermal for this little instrument on this little spacecraft in this particular environment was, was probably our biggest challenge. After that, mass was a, was a, was a bogey that we had to worry about. And we, we did some tricks to lighten up things, used some magnesium components here and there for certain chassis to lighten things up. And that was successful. And then power, of course, we wanted to keep the power as low as we could. And this instrument burn, when it’s on full tilt burns about 16 watts and the whole power budget for the whole spacecraft is a little, just shy of a hundred watts. So you can imagine when we’re running, we’re, we’re 20% of the power bill, you know, that that’s, that’s not trivial. So, anyway, I did say a lot there. I hope I answered your question appropriately.
Host: You did; very, very thoroughly, too. We’re, we’re, you’re, we’re exploring all the challenges with the, with the thermal constraints. Really, I, I want to, I want to pitch over to Pamela to sort of, add some context to, there, from, you know, Cliff was mentioning a lot of engineering challenges to, to make this work. But I don’t think we’ve, we’ve explored too much as to what we’re trying to do. I think from a high level, we understand we’re trying to map the Moon for, for, map the lunar surface for the presence of water, water ices. But I want to understand sort of how we’re going to do that, from the tactical perspective of flying around the Moon and, and using this instrument, calibrating it, really the, the mission operations side. How is this going to work once you’re deployed from the, from the SLS, what happens to actually execute the mission?
Pamela Clark: So, first of all, we have to go on a low-energy trajectory, which will involve traversing through space on a low-energy trajectory for months on end before we get into a position to, to get into lunar capture. And once we’re captured, we’ll do what’s called periapsis lowering to get into a final science orbit. And along that path we’ll actually be doing some inflight calibration looking at the Moon and perhaps several other targets to be able to verify the spectral and radiometric performance of the detector. Then we’ll get into a lunar orbit, a lunar orbit that will have a repeat pattern that will allow us to go over the same real estate on the lunar surface at several times of day. And the reason we need to do that is because we need to come up with a, a better, better model of water physics. Why is that? Well, because during, when it gets cold on the Moon water molecules get cold trapped. A hydroxyl, which is a component made from interaction of the, of solar protons with water molecules, also basically stick, get absorbed, on regolith particles, and, where, where do they end up? How much is there, how much is on the surface, where specifically do they end up? So what we’re looking at is a, a resolution of about kilometers, tens of kilometers, maybe 20, 30 kilometers, which is kind of intermediate between what the neutron spectrometer data has told us about water on the Moon over relatively large areas, and what we can get from LRO pictures combined with the diviner data on temperature, that give us the sense of what local cold traps could be. So the question is] can we find a terrain which has enough local cold traps, where there are shadows for, especially as we go further north or south at higher latitudes, where the shadows persist for longer. And there’s been some work now that’s indicated that even after the shadows, towards the middle of the day, aren’t there, the, the areas still continue to trap, trap some water. So how persistent are these, how long do they last, how much of a particular part of the terrain could be covered with these cold traps? And that will imply, although we’re looking at surface data, it is true, that will imply the possibility of water in the, basically below the surface as well. Now, you know, there are two other missions that are flying at the same time that are going to look at the South Pole, particularly. The Lunar Flashlight will look for the presence of surface ice at the South Pole. And then LunaH Map, which will look for, at, at higher resolution, because, very close to the, to the, to the surface, we’ll look at water protons, basically, to a depth of a meter, which will imply the presence of water. And that’ll kind of tie in, in terms of we’ll see what’s going on at the poles with actual ice, but understanding the water cycle as a whole, and also, basically, the origin of water: is it coming from the interior, strictly coming, has, has it come from impacts of, comets or meteorites with, with that, contain, that that contain volatiles? So, you know, we don’t, this will help us to get a much better handle on the water model and that’ll help to explain the water at the poles as well. All this is, you know, it’s, it’s nice to have a mission that’s actually very practical and also gives you, can give a lot of scientific insight and, and I think Lunar Ice Cube does.
Host: Yeah. And it sounds like, from what you’re saying, Pamela is, it’s one of many instruments. Of course, we have LRO there as well, with its own instruments that are continuing, continually mapping. You mentioned a couple of others, Lunar Flashlight, and, and, and on some of these others. So it’s really contributing to the broader picture.
Pamela Clark: Right, and Lunar, Lunar Flashlight is, has a, basically is a, laser-induced and then measured with a detector back at the, the spacecraft. And they’re all three different instruments, and LunaH Map is a neutron spectrometer. So, three different instruments, and that’s complimentary, and helps to constrain models, too, when you have different kinds of data from different sources.
Host: So as a scientist, when you’re looking at these models, what, what is the hope? You have all these, you have all these instruments looking at the different pieces of, of mapping the lunar surface, and so when it all comes together what’s, what’s the idea here: you have a better, you, you mentioned a better understanding of water ice and its movement over time, what, what does, what does that mean? What does that helping you to explore?
Pamela Clark: Well, it’s a four-dimensional understanding of water: how persistent it is, how much there is? Give us some insight into the origin. Is it interior? Is it outgassing? Is it exterior? Is there actual production of water going on, on the surface? And all of these pieces of information, when combined, will give us a much more comprehensive model of water, and by implication other volatiles, and that will help us understand where we should look for water, where we should send those rovers to drill for water, how much we might hope to find, is what we see on the surface an indicator, is it a signature, for what we might see underneath? And all these things will help us, if we want to actually see water as a resource, these are the kinds of reconnaissance kinds of data that you need to have to be able to know where you want to put your, you know, equipment to actually try to extract resources.
Host: Understand. Yeah, you’re talking about, yeah, we’re doing all the work ahead of time preparing for those Artemis missions on when we’re going to be walking on the surface. We know where some of the most, the more interesting places are. And then the more that we can characterize it ahead of time, it, it sounds like you’re talking about drilling and, and, and that sort of thing, we can, we can have a better understanding of what we need, what other hardware and stuff we need to develop and, and what instruments we need once we’re there because we’ve done all the homework ahead of time. We’ve, we’ve characterized the surface with all these different instruments.
Pamela Clark: Yeah. Where we, particularly where we need to go. And you know that, you, you’d like to be, you know, select sites where you had a higher likelihood of actually finding something and doing it faster so that, you know, you don’t have to expend as, invest as much in, in looking around. So these are all things that help to constrain a problem, that basically a way to get an understanding of where there could potentially be water reserves. Where, it would be in the form of ice – you know, when I say “water” please understand I include ice; I include water in all forms: H2O, also hydroxyl, which is a component of water.
Clifford Brambora: And if I might add, I think, you know, ultimately, there are so many extremely exciting things that can come from this mission and this scrutiny of the Moon. And, you know, it, it, it, in my view and what I’ve understand to be the, the, one of the future goals is to actually, you know, have a, a presence on the Moon where we can perhaps, you know, harness that water — and it would have to, I think for survival — and then the Moon could become like a launching point for, its very sci-fi sounding, for Mars or other areas. So, so, you know, I know Pam has spoken very excitedly about this type of thing, of having a presence on the Moon, to me in the past, we’ve had many conversations about it, and this, this to me is the, these are the baby steps you need to take to, to, to convince people on the planet Earth that, that this can be done. And, you know, you need water, and from water you can make fuel, you can get hydrogen, you can, you can do a lot of really interesting things. So that’s the long game.
Host: Yeah. Yeah. Talking to you guys and talking to a lot of, a lot of folks, I think, I think, you know, there’s a lot of cool, cool, you know, grand ideas. And, and I love that. I found just from talking to a lot of folks like yourself that when, whenever we’re trying to think about some interesting concept, right, so, so we’ll take, we’ll take Lunar Ice Cube for, for example, just the idea of we have a, we have a significant engineering challenge, and so we are going to, we not only do we have to explore the lunar surface and we have to map it using these infrared cameras, or infrared spectrometers, we have to, we have all of these engineering constraints with, with thermal and with, and with, the, the size that we were talking about, the power constraints, those sorts of things. And we have to tackle just that. We have to tackle all of these different things and come up with, and, Cliff, you expressed how creative you and your team had to be to solve these issues. I think even just, I mean, you, you’re contributing to something so much bigger. And, and when you actually tackle these, you’re taking such a significant step and, and coming up with creative solutions to get us there, and just, it, it’s really just a fact, too, that every step along the way contributes so, so much more significantly than you would’ve thought, right? You think, OK, first, at high level, we have to, we have to map the lunar surface with, with this infrared spectrometer, and, and we have to discover water ice. OK, cool. We breeze right past it. But really if we focus in on it, look at all the challenges that we had to solve just in this step. And so, so really Cliff, I’m — this is props to you and your team and to Pamela as well, really for, for, for tackling some of these significant issues. And just noting that, that of, of what it takes just to accomplish a mission like this, right, you’re talking about grander ideas but, but it’s really, what you, what you and your team have contributed is, is quite significant.
Clifford Brambora: Well, thank you. I appreciate it. And, you know, it’s been a very large team, multi-institution effort. And, and I have to admit this, this has been just one of the most satisfying, cooperative, activities of my career, to be honest, working on such an exciting program and working with Pam, in, at, and Morehead and the, the excellent leadership and everything that’s been going on, the engineering was also fantastic at Morehead. And, you know, this whole system is very complicated and, and I, I, I also appreciate the support we’ve received from our headquarters folks — Andres Martinez is part of the AES crew there, and he’s just been a stalwart supporter of our, our, ever-increasing scope of things we wanted to do, and he had to pull the reins back a few times but, you know, for a CubeSat, we, we did a lot of iterative engineering here. We did a lot of upfront testing, and granted we did it as cheaply as possible and as quickly as possible, but, but we, we, you know, any notion that you can just start from a clean piece of paper and go right to flight is, is fraught with risk. You really need to take baby steps. You need to iterate; you need to learn. We, we had to redesign the entire thermal system for how this instrument is, is cooled about two years before we went into thermal vac, it was a big right turn in our understanding of how this was going to work, and we had to, we had to pivot with that and, and come up with solutions, and we did. And, it was really, it was actually, it was fun. It was exciting to, to, to have to see these challenges and come up with a solution in a, in a quick amount of time. So, very innovative thinking from all sides and, you know, is really, it’s very exciting.
Pamela Clark: You know, I’d also like to add, if I can, this is a first-generation, using a first-generation CubeSat, you know? CubeSats, basically with the idea in mind of a rapid developed, streamlined, you know, standardized, basically container, with relatively small number of options for subsystems, which was developed for low-Earth orbit. And the difference with a deep space CubeSat, I mean, one of the differences is, well, it’s far more challenging environment for one thing, but in addition to that, you have to have all the active control systems you do on a regular deep space spacecraft. Can’t take advantage of being in orbit around the Earth with a magnetic field using magnetotorquers to control your alignment, for example, among other things. So getting this to work and also understand that, I mean, the people who did the building, a lot of the building spacecraft were students. So we’re giving students firsthand hands on experience, using a, marrying a CubeSat model, with a, you know, basically our space engineering model. And you need to be able, you need to find where that sweet spot is to combine both of those approaches. So that in the future, basically based on lessons learned from what, 13 different selected projects that were supposed to be flying on Artemis, that will actually have a, a good place to stand for the next round. And, you know, we were all basically operating in parallel. So that meant that sometimes we were independently reinventing the wheel. Sometimes we were having some of the same issues, sometimes different ones. There are certain ones like thermal that pop up consistently, but I think that, we hope that we can incorporate these lessons learned and make the next round, you know, basically, easier go, but there’ll still be challenges. Just remember, I will get this as like NASA’s first decade when, you know, NASA was building spacecraft for the first time and they didn’t even give anything a name until it actually got some data back from space. And they just, they had a failure, they just made a little tweak and sent up something else and flew it, you know, try it again. And at the end of that decade, going from maybe, you know, a less than 50% success rate, we were at amazing a hundred percent success with Saturn V. Amazing. Well, so this is all, this is, again, this CubeSats offer a lot a lot of opportunity to send little fleets of standardized spacecraft all over the solar system and a lot, get a lot more systematic data on the things that are, the things that are going on in three dimensions and four dimensions over time.
Host: Incredible.
Clifford Brambora: Yeah, That, that’s a great point. And, and I really, think it’s great how Morehead University has involved students. And it, and it’s, and as Pam said, it’s, it’s not only in the design and manufacturing and, and engineering complexities of making Lunar Ice Cube a reality, but also on the ground system side, Morehead University is, has an incredible, you know, communication capability at that, that contributes to how we get the data down and how we command the spacecraft. They, they, they actually have the ground system for this, set up there and, and, and, and that, that’s huge, and that’s a big part of their aerospace program. So it’s, it’s been, it’s been, I’m so glad Pam brought it up, that the, you know, the, the mentorship, the, the, the seating of all these minds of people studying this is, is just invaluable. This is terrific. So, and we do it at NASA too, of course, but I have to admit, you know, I’ve worked with many different institutions over the years, and I’m very impressed with Morehead aerospace program and how they bring their students in to help. And it’s also a very affordable thing to do too, as you imagine, because students don’t cost as much as senior engineers. Of course. So it’s, it’s really a win-win.
Host: Win-win, I mean, you get a lot of a lot of different experiences. You get a lot of eyes on it, very truly collaborative. And then, and then it ultimately all comes together. Pamela, you were, you were mentioning a couple of, you know, you obviously are thinking about some of these challenges, and we went over them a lot, a lot today. But just when you look at the mission itself, we talked about what it’s going to be doing. I think, where we can get some clarity is how long the mission is supposed to be going on? Obviously, you have these challenges that you’re working, but is, is the ultimate goal to map the entire lunar surface, for example. And it sounds like you’re taking multiple passes over the same areas, as you mentioned to, to calibrate and stuff, but is the goal is the goal to thoroughly map the, the entire surface? And so, so what does that mean for, for the operations, for the continued operations of overseeing this payload and to, to make sure you’re getting the data that you want? What is, really what I’m trying to get at is what is mission success for you?
Pamela Clark: So actually, it does not map the entire lunar surface. We hope to be able to go back over to the same real estates once a lunar cycle. And I think that if we do this for several months, we might get something like 10% or 20% of the lunar surface. We will preferentially, we’re basically coming up from crossing the terminator at the south pole to start taking measurements. We’ll start on the earlier times of day. And that’s actually when we’re have to see the most water as a function of time of day. And, you know, so the, we’re talking about a nominal six-month mission. Once we arrive in our final lunar orbit. It’ll take probably two or three months to periapsis lower from initial lunar capture, which we might occasionally take some data. And then before that, we’ll be doing a low-energy trajectory. And the length of that low-energy trajectory will depend greatly on the date which we launch. It, it varies considerably from day to day and week to week in terms of what that will be exactly, you know? Where we’ll end up with the range points will, will swing around. How we’ll see the Earth on the Moon on the way out there? How far away we’ll be from the Earth, even. So, you know, we’re talking about something that could vary from several months to nine months in, in duration. So we’re hoping basically based on the, what we can, you know, our, our, our, our likely, lifetime survivability of parts that we’re talking about a mission that we can probably do within under two years a year and a half, nominally. And that should be OK for, you know, the radiation hardness of the parts that we have on board, for example. And so, that’s what, and what, what we will do then, when we initially proposed, we were not required to deliver data to a public archive. And then a year or two, after we started, we were required to deliver data to a public archive. And, you know, frankly, just as well, because we’d like the data to be used, but that certainly involves the kind of data production and management that’s beyond the original scope of the mission. So we had to ask for some additional resources. And so, our plan basically is to deliver the raw data, like what’s called level zero data to an archive as soon as possible. As we take the data, it’ll be thoroughly, there’ll be a lot of metadata to go with it, to describe exactly what the data is. Well, the important information on how housekeeping associated with the instrument, and then over a period of time after the mission ends, we’ll, we’ll do the correction and calibration. And that will definitely involve folks at Goddard to, to do that based on the ways that the OVIRS, the treatment of the OVIRS data with some additional steps for this particular instrument and orbit around the Moon. And then from that, we will produce a look at the relative variation in absorption features for the areas on the Moon that we’ve covered as a function of time of day and latitude. And those should be made publicly available. The planetary data system, which is the public archive for planetary data has agreed to come up with a, a model, which is a little easier and less expensive for extremely cost cap missions to, to deal with. And we’ll be, we’ll be using that to, to capture the data and make it available in an archive, which will be indefinitely available to the public. That’s something that, if you don’t do, then, you know, there’s no way that an institution can make a commitment to, and, you know, in basically forever maintaining an archive, but it will be at the planetary data system.
Clifford Brambora: Well, one of the things I’d like to add to that, if I might is, is that we, as a, as one of the, you know, originally planned 13 hitchhikers, if you will, on this really impressive mission. We are literally the tail wagging the dog. I mean, we, what, what is important to our little CubeSat as compared to Orion and SLS and, and, and, you know, we, we, and this tails right into what Pam was just talking about, our launch date has been sliding month to month to month, because we’re completely dependent on the rocket. And when it goes up, so we’re just like, hey, whatever happens, you guys got to deal with it. We can’t say, please launch on the 23rd, not the 22nd. They’re not going to listen to us because understandably, we’re just a little, we’re just a hitchhiker. We’re just, we’re just like getting this opportunity. So, so it makes planning that Pam talks about very challenging because we’re constantly iterating how our path through space is going to change on a given launch date because the universe keeps spinning around and anything, all the positions of everything keep changing. So when we launch, when we get to the Moon, the path we have to take to get there is all a function of launch date. And then it’s, it’s just a reality of CubeSat, you know, and we, we don’t have a dedicated rocket setting just us up we’re, we’re part of a big system. So I guess an important, another challenge associated with these low cost missions is, is this, this, this particular item I just mentioned.
Pamela Clark: You know, this gets into the whole lessons learned area. If you want to talk about that, I’d be very happy to. In terms, in terms of what a drifting launch date, but also in terms of what really would make sense as an architecture, first, you know? Really small compact spacecraft at which there could be many because they’re relatively expensive to, to build once we get the model right. And the relatively low mass and low volume, really an architecture which could actually deliver a bunch of these to your target, which means you could have a smaller propulsion system, there’d be, they would be less time would be involved. You could spend more time at the target, would be a nice architecture to consider in the future. And I think that this will actually happen when we get a commercial launch services start to be viable for the Moon. And then you, of course you basically have an agreed upon, you manifest, and have it agreed upon launch date with some backups, but not, you know, we’ve had delayed launch dates for, for a long time now. And that means we’re completely redoing the trajectory analysis and, you know, planning for when things are going to happen, including inflight calibration. If you want me to talk more about lessons learned, I’ll be happy to do it, or we can talk about something else.
Host: Well, let me, I guess in a, in a similar vein, what I, what I like to do is, I’d like to toss to each of you, and, and just sort of capture this moment. And, and you can of course, fit some lessons learned and in there as, as you see fit, but really what I’m trying to capture, is more of an emotion. Like, you, you’ve mentioned all the work that’s gone into the Lunar Ice Cube mission so far. And Pamela, you, you laid out years’ worth of work ahead of time. After the, after the mission, just, just, there’s a lot of, there’s a lot of follow up to this. You mentioned that the, the launches are, is, is getting delayed, but, but I mean, it’s, it’s very close. We’re not talking about something that’s years away anymore, right? We’re talking about something that’s months away. It’s, it’s very, very close. So, so with that in mind, what I wanted to capture was just sitting in this moment ahead of launch. The anticipation. Of course, you have some work to do with, with coming up with trajectories, but just trying to capture, how you’re feeling in this, in this moment, just ahead of launch? Knowing all of the work that’s gone into it, where you’re sitting right now and what’s ahead of you, just capturing all of that, how you feeling?
Pamela Clark: Well, you know, I think it’s about time. I mean, I, I say this as somebody who, I hate to say this because it’s going to date me, but I actually met Wernher von Braun. I’ve known many of the astronauts and I feel strongly that we should be back on the Moon and have permanent bases on the Moon. And be exploring the surface that using it as a jumping off point to a lot of other interesting exploration of the solar system. So I’m hoping that this is like just the beginning, by, you know, doing this kind of reconnaissance of something that will be much more involved and involve real, you know, really, human exploration beyond the Earth and open up a whole new chapter, certainly in this country’s history, but basically in terms of where humans are and where we can go in space. And I’ve had this desire since I was very young, you know, almost as far back as I can actually remember. I wanted to, you know, be a space explorer for very early in my life. So it’s very important and I’m happy to be involved in a, in part of the process, try to make this happen. That’s how I feel.
Host: Very good. Yeah. And you are truly exploring space. Cliff, over to you. Same question. All the work that’s gone into it, you’ve solved the number of engineering challenges. I’m sure you’re going to be staying tuned to see how everything works, for the months ahead capturing this, this moment ahead of launch, how you feeling?
Clifford Brambora: Yeah, I, I wanted to first echo what Pam said. I think it’s incredibly important that we, we, we figure out how, how we can get to the Moon and have a sustained presence there for purposes of, of leaping outward to other greater things. I think that’s incredibly exciting. For me, personally, I’ve worked on this instrument for over five years, I think at least six years now. I think we all have at least six years in on this. And another lessons learned, you know, you need more time than they think it’s going to take but here we are. And I’m, I’m, you know, my engineering thought process focuses on, on the, the, the design of the instrument, the spacecraft, the, the risk posture that is, is typically associated with the CubeSat-type development effort. You know, this isn’t James Webb Space Telescope. There’s, there’s no redundancy here. You know, one little thing goes wrong, and we could have a serious problem, but, you know, we did our best to avoid those situations with picking out high reliability parts, and different good systems and margins and things. But, but I personally, am so looking forward to it being turned on in space to do one of these in situ observations that we’re talking about and knowing that it’s working and that we, we, the various risks that exist have been beaten down. It’s, it’s just like what, what James Webb went through when they had over 300 separate deployments and any one of them went bad, the missions a goner, you know, and they, they thankfully got through all those deployments and everything’s great. But that was a class A mission, full blown redundancy, crazy amounts of money, you know, you know, just to get this thing up there with lots and lots of high reliability stuff, this is a CubeSat. This is the opposite end of the spectrum. This is about as inexpensive as you can get to put science up into orbit and or look at the Moon. And we’re leaving the Earth, we’re going out to the Moon. You know, that, that, I don’t think that’s happened. We haven’t set a CubeSat out to the Moon yet. Correct me if I’m wrong, Pam, but I think this is first, right? So this is a first.
Pamela Clark: This is a first. Yeah, well, it isn’t the first deep space CubeSat, that was MarCo (Mars Cube One), but it will be the, but it will be the first CubeSat to the Moon. Yes.
Clifford Brambora: Yeah. And, and the Moon is a harsh and environment. There’s radiation, there’s thermal. So, so we’re very, so, I just want to see it succeed like you, you already, implied, but I, I want to make sure that the things that we worked on, work and work reliably, and once I have a feeling that they are, I will, I’ll sleep better. [Laughter]
Host: Well, I, I, I appreciate talking to you both. What I, what I appreciated about — what I captured in your answers is, is of course, you’re looking forward to this mission, but it seems like you both have a sense of contributing to something grander, contributing to a goal that you both strongly believe in is this continued presence because you both, you know, obviously see, see the value in what’s to come and, and that’s, I think that’s, an very important takeaway. So I think on, on that note, I think that is the perfect place to wrap up our discussion. I learned so much about Lunar Ice Cube. And I’m, I’m, I, I don’t know if I’m just as excited as you are. Of course, you guys put in, put in so much more work, and have, are intimately closer to this mission, but, but I am truly excited for you and for your teams. There’s, there’s a lot of cool stuff that’s going to come from, from this mission and, and thank you for both of you for coming on the podcast and helping me to, to explain it and to our listeners as well. Wishing you the best of luck. Thanks for coming on.
Pamela Clark: Thank you. Great opportunity.
Clifford Brambora: It’s been, it’s been an honor working on this and I appreciate the opportunity to talk about it.
[Music]
Host: Hey, thanks for sticking around. I got really excited talking about the Lunar Ice Cube mission with Dr. Pamela Clark and Cliff Brambora today. It was awesome. I hoped you enjoyed it as much as I did, and you’re excited for the Artemis mission. Of course, there’s a lot more to it. That was just one piece. Check out NASA.gov/Artemis to learn more about the whole effort. We’ve been talking a lot about different aspects of — the Artemis program and the Artemis I mission, especially recently, you can check out our full collection of episodes at NASA.gov/podcasts. We have a collection called the Artemis missions, Artemis episodes, and you can click on there and listen to any of those in no particular order to check those out. There’s also some great other NASA podcasts we have across the agency that you can check out there. NASA.gov/podcasts. If you want to talk to us, ask a, ask us a question, just make sure to talk to us on Facebook, Twitter, and Instagram. We’re on the NASA Johnson Space Center pages. You can use the hashtag #AskNASA to submit a question or submit an idea. Just make sure to mention it’s for us at Houston We Have a Podcast. This episode was recorded March 14th, 2022. Thanks to Alex Perryman, Pat Ryan, Heidi Lavelle, Belinda Pulido, Laura Rochon and Jayden Jennings. And of course, thanks again to Dr. Pamela Clark and Cliff Brambora for taking the time to come on the show. Give us a rating and feedback on whatever platform you’re listening to us on and tell us what you think of our podcast. We’ll be back next week.