Season One | Episode 5
Interstellar: Deep Space Travel
Thank you to our guest on this episode of Lockheed Martin Space Makers for her time and expertise:
Dr. Christine Edwards from Lockheed Martin
[00:00:00] Host: Welcome to Lockheed Martin Space Makers, the podcast that takes you out of this world for an inside look at some of our most challenging and innovative missions. My is Ben, and I'll be your host. This season, we'll explore the future of space, with past and present missions that are shaping our path forward, and chat with experts about what they think the space industry will look like 30, 40, even 50 years from now. Now let's go for launch. In today's episode, we talk with Dr. Christine Edwards.
[00:00:38] Dr. Edwards: I'm the Deputy Exploration Architect at Lockheed Martin Space.
[00:00:42] Host: And we will learn a little more about what space exploration and deep space travel could look like for humans in the future.
[00:00:48] Dr. Edwards: My team looks at the kinds of missions that NASA, industry, and our international partners want to perform in the future, and we develop concepts and early systems designs that could help accomplish those missions. It's like we try to peer into the future and envision what the future of space exploration could look like. Then we architect the spacecrafts that could enable that future, creating conceptual designs of their systems and missions to make that future possible and bring it into existence.
[00:01:20] Host: Before we dive into the details about the future, let's take a step back and look at where humans have been and how we got to where we are now.
[00:01:29] Dr. Edwards: First thing I think of is the Great Space Race back in the 1960s, and how much those early crewed missions were journeying into the unknown, with like that first achievement of suborbital and orbital space flights. The first landing on the moon was a monumental achievement.
[00:01:51] NASA Audio - Neil Armstrong: "That's one small step for man, one giant leap for mankind."
[00:01:54] Dr. Edwards: And I grew up in the shuttle era and was inspired to s- study aerospace engineering after watching a movie on the space shuttle. Feeling that boom and thunder of the rocket engines in that theater and imagining what it would be like to be an astronaut going into space really inspired me. Since Apollo, we've had the space shuttle and the International Space Station in low earth orbits, or LEO, and those missions have significantly increased our understanding of how to live and work in space. Now with the Artemis Program, we get to apply that knowledge to a more sustained exploration of the moon.
[00:02:29] Host: Artemis is the name of a NASA program that is going to bring humans back to the moon, and Lockheed Martin is the prime contractor that built the Orion spacecraft. It plays a critical role by carrying astronauts from Earth to lunar orbit and back.
[00:02:45] Dr. Edwards: It will take astronauts from the Earth to The Gateway, which is a space station around the moon. The astronauts will board a lander that will take them to the moon's surface. After the surface mission is complete, they will launch back to The Gateway from the moon, board the Orion, and then head home. This time, we are going to the moon to stay for more long term and to prepare for expeditions to Mars. Mars is the ultimate goal for human space flight. Everything that we do in LEO and at the moon can drive us towards being ready for those missions.
[00:03:16] Host: Except for the Apollo Program, humans have spent most of their time in low earth orbit at the International Space Station, which orbits around 260 miles above Earth. NASA's Artemis Program is planning on sending humans 250,000 miles into deep space to the moon. To give you some perspective on just how far that is, imagine holding a basketball; this represents our Earth. The International Space Station should be approximately one centimeter from that basketball. Now imagine holding a softball. In comparison to our basketball, this proportionally represents our moon. To see how far we'd have to travel to the moon, you would have to move that softball away 24 1/2 feet. This is more than just something fun to do, but an excellent visual representation of the great distances we are traveling from low earth orbit to our moon. This visual also helps us better understand how far the Orion spacecraft will be traveling, as it takes humans safely to the moon and maybe one day, beyond, to Mars.
[00:04:23] Dr. Edwards: The biggest difference between LEO and deep space is energy. The further away from Earth you wanna go, the more you need to get out of Earth's gravity well, the more energy you need to do that. And it's the same for coming back, but opposite. Coming back to Earth from deep space, you need to get rid of a bunch of energy. That's why you see heat shields or tiles using the Earth atmosphere to slow you down. When you are returning from LEO, you come back at around 17,500 miles per hour, and your heat shield heats up to around 3,000 degrees Fahrenheit. But when you are returning from the moon, you come back at almost 25,000 miles per hour, and your heat shields has to take over 5,000 degrees Fahrenheit. And then Mars is even higher. So, in addition to having that beefy heat shield so you can return from deep space, I also think about how to keep a spacecraft operating safely.
[00:05:17] Host: The crew's safety during an Earth-bound atmospheric entry is just one of the major challenges of sending humans into deep space. Mission designers have to consider a whole new set of variables when sending people to the moon or Mars that they wouldn't necessarily consider when going to places closer to home, like the International Space Station.
[00:05:38] Dr. Edwards: A crewed mission to Mars could take two to three years. And if something fails on that spacecraft, you can't just call a taxi; instead, you want backup systems. For example, on Earth, when a power grid goes out, critical infrastructure will have backup systems, like a hospital has backup generators so that people on life support can stay alive. You need similar backup systems on a deep-space spacecraft, too. The Orion has been designed for crewed deep space missions, including the safety features like the backup systems to keep the crew safe and a heat shield that sized for those high-velocity re-entries from the moon. In fact, we've shown that the Orion could support a Mars re-entry in a contingency scenario, too. Let's say you have a failure on your Mars transit vehicle, and it can no longer perform the braking maneuvers that you need to get back to Earth. If an Orion is attached to a Mars transit vehicle, it could be a backup system providing the safe return to the Earth.
[00:06:42] Host: Christine's team has their eyes set on going back to the moon and looking beyond at how lunar bases will evolve to one-day support missions going to Mars.
[00:06:52] Dr. Edwards: Well, the sky is no longer the limit. We have the first woman and the first person of color landing on the moon with Artemis. After that, we will see the first sustained presence on the moon by establishing infrastructure like power generators, rovers, and habitats so that crewed missions can keep returning to the moon. And with those sustained lunar missions, we can test the technology and systems that are needed to bring human space flight missions to Mars. So I see humans traveling to the places where we've been dreaming of going: lunar bases and finally having missions to Mars.
[00:07:27] Host: And for these missions to be successful, you need to have more than just one type of spacecraft, but a space infrastructure that will support humans on these ventures.
[00:07:38] Dr. Edwards: For lunar and Mars missions infrastructure, I think of the need for base camps. When I went on an expedition with the Denver Museum of Nature and Science, we set up a base camp where we had tents and stored all our food and equipment. And every morning, we would gather up the supplies we needed for that day and hike out to work and then hike back at the end of the day to recoup. We are envisioning similar infrastructure for the moon and Mars. On the moon, NASA is planning an Artemis base camp, which will have a power generator and habitation. Landers will deliver crew, food, and supplies to that base camp, and the astronauts can take the rovers to do expeditions around the base camp.
[00:08:19] Then, for Mars, at Lockheed Martin, we've been developing a concept that's called Mars Base Camp, which is actually a vehicle that transports astronauts to Mars, and then parks in orbit around Mars.
[00:08:31] Host: Let's take a moment to listen to a few experts at Lockheed Martin that explain how Orion and Mars Base Camp will work together to send humans to Mars.
[00:08:39] Dr. Edwards: To get humans to Mars, we can't send Orion by itself. It needs to be part of a larger system that provides the supplies and the scientific equipment needed for a three-year journey that will take us hundreds of millions of miles away. We call our concept Mars Base Camp. Of course, the six astronauts will need room to live on their thousand-day mission, so Mars Base Camp has two habitats and a living space to eat, sleep, and exercise. Most importantly, we have Orion. It's the command deck with all the avionics for navigation and communications. Orion makes the whole spacecraft more reliable and gives the astronauts a safe ride home. And that vehicle in Mars orbit is your base camp, and you do expeditions from Mars Base Camp in orbit, down to the surface of Mars, or to the Mars' moons.
[00:09:40] Host: In a similar way to the International Space Station, you could have space stations orbiting around the moon, like the Lunar Gateway, and around Mars, like Mars Base Camp. These space stations will sustain the astronauts who will be living there for an extended period of time, a home away from home while they are working on missions at those locations.
[00:10:03] Dr. Edwards: The International Space Station is a very capable vehicle, and it has all of the supplies, and food, its equipments for the crew to live there and to perform science and other work there.
[00:10:15] Host: On the International Space Station, the crew can watch movies, listen to music, read books, play cards, and talk to their families. They have an exercise bike, a treadmill, and other equipment to keep their bodies and minds healthy. And of course, necessities like prepared food, a bathroom, sleeping quarters, and first aid equipment are available to them if they need it. However, for deep space missions, you need all of that and more to sustain astronauts. Because unlike at the International Space Station, the next shipment of supplies could be years away.
[00:10:49] Dr. Edwards: So the supply chain can be challenging, uh, because you need to make sure that you have the food and supplies that you need at the location where you need them, and you could be traveling hundreds of thousands, to millions of miles away for these deep space missions.
[00:11:04] Host: The International Space Station receives deliveries from Earth every couple of months, with food and other much-needed supplies. But in deep space, those regular deliveries wouldn't be nearly as easy, which is why you have to think about taking everything you would need for the entirety of a deep space mission. Along with a host of other challenges we will have to solve, developing some type of supply chain will be necessary to support astronauts operating in deep space.
[00:11:32] Dr. Edwards: One of the challenges is radiation exposure. We have a payload flying on the next Orion mission that is currently being tested by astronauts on the International Space Station, and this payload is a radiation vest. It is specially designed to fit each astronaut in a way that it provides extra radiation protection over vital organs.
[00:11:51] Host: Radiation is measured in millisieverts, and a six-month stay on the International Space Station exposes an astronaut to roughly 50 to 100 millisieverts, according to the National Academies of Sciences, Engineering, and Medicine. For a comparison, an x-ray at the doctor's office is about 0.1 millisieverts. Now, left unchecked, this increased radiation exposure can cause a lot of problems for astronauts, most commonly increasing their risk for cancer and other issues like cataracts or infertility.
[00:12:25] Dr. Edwards: The radiation is coming from.. the sun is one of the primary sources of radiation, and then also from deep space. And every astronaut is considered a radiation worker, so they have a set amount of radiation that they can have in their lifetime and in their work. And NASA's very careful to make sure that they don't get exposed to more than that level of radiation. Right now, for whenever there's a radiation storm from the sun, the astronauts hunker down inside an area in the spacecraft where they've determined it's the safest from the radiation, and so they go to that location. Orion is designed with some radiation shielding, and then the vests can provide additional protection.
[00:13:07] Host: To help solve this challenge of radiation of deep space, Orion's equipped with a radiation sensing instrument called the Hybrid Electronic Radiation Assessor. It will provide a warning to the crew to take shelter in the case of a radiation event. Let's say they're warned of an impending solar flare. Orion's crew can take cover in the central part of the crew module between the floor and the heat shield. They could also use the stowage bags on board to improve their shelter. However, the crew may have to shelter in place for more than a day. But with the help of a protective vest to block solar energetic particles, the crew could continue critical mission activities despite a solar storm.
[00:13:48] Dr. Edwards: Another challenge is communications with crew in deep space. We can send communications to spacecraft at the speed of light. But when you get as far as Mars, the minimum communication delay from Mars to Earth is around seven minutes, and then the longest one is around 20 minutes. You are so far away that it takes up to 20 minutes for a signal to reach you from Earth. And then it takes another 20 minutes for them to hear back from you. So, you are really remote and cut off from human contact outside of your crew that's onboard the spacecraft. The challenge here would be for the Mars crew to be as self-resilient and autonomous as possible, being able to troubleshoot and solve problems with only delayed assistance from Mission Control.
[00:14:30] Host: Unless we can find a way for signals to move faster than the speed of light, there is no way to solve this communication delay. However, one way around this delay is to establish mission control communication centers at or near the locations where astronauts would be performing missions.
[00:14:47] Dr. Edwards: So, in the future, Mars Base Camp could be like that mission control that's local, that's at Mars. If you've designed it to be more autonomous and to really be able to provide some of those mission control-type capabilities, then the crew can be more autonomous too and not have to rely as much on support from the grounds from Earth.
[00:15:07] Host: A "Mars Base Camp" acting as a mission command and control center to help cover the communications gap for operations touches on an idea of being untethered from Earth. Being untethered is when astronauts become self-sufficient enough to where they will no longer have to rely entirely on Earth's resources to sustain themselves. In the future, untethering from Earth may be possible with the help of water.
[00:15:35] Dr. Edwards: There are a few tipping points that I'm tracking and even trying to make possible. One we referred to as the Water Based Economy. We now know that there's a lot of water on the moon from the science orbiters that have mapped it. It looks like there's more water there than we ever imagined, than we ever thought was possible. It's a lot of water, surprising amount of water. But we don't know how accessible it is, it could be all tied up inside rocks, and a lot of it is inside craters. It could be water that's a little bit hard to reach. So we definitely wanna send robotic spacecrafts to go and explore how can we get that water. And if we can mine that water, which is called In-Situ Resource Utilization, or ISRU, we can use that water to make propellant and breathable air. When it becomes more affordable to use those ISRU materials from the moon than to haul them all the way from Earth, that is a tipping point. That point can spark a water-based economy where we can use water on the moon to fuel missions around it and to fuel missions to Mars. In our concepts for Artemis Base Camp, we have been thinking about how can astronauts operate at that camp and do things like assist with harvesting water and run the systems that can help us to use it.
[00:16:57] Host: Extracting water from lunar soil will require a ton of ingenuity and technical innovation. Developing techniques to harvest this water will support bases operating on the moon and work out the technologies and best practices needed to support missions going to Mars. And this leads us to our next point: If we are going to be untethered from Earth, we have to go nuclear.
[00:17:21] Dr. Edwards: I am super excited about fusion. I really wanna see compact fusion reactors happen. The energy from fusion is about one million times more powerful than the chemical reaction. And it's two to four times more powerful than fission reaction. In the future, if we have them adapted for space, they would revolutionize how we operate spacecraft. Power would no longer be as much of a limiting factor on Earth and in space. Nuclear energy also solves the problems we have with generating enough power on the surface of the moon or Mars to perform all of the activities that we have planned, but it could power an entire moon base or an entire Mars base. On the moon, the nights can last up to 14 Earth days, and you need power to keep your crew habitat warm enough to get through those nights. Also, the amount of materials that we can mine from the moon's surface will be limited by how much power is available. And on Mars, there are global dust storms that block light from solar panels, and that caused the loss of Opportunity rover. So, in those cases, having a full-on nuclear power plant could really enable, uh, the mission.
[00:18:32] Host: So you're gonna need like nuclear scientists.
[00:18:36] Dr. Edwards: Yes. [laughs]
[00:18:37] Host: Who will need to become astronauts.
[00:18:39] Dr. Edwards: Yeah. [laughs] I'd imagine needing all sorts of job functions, the kinds of jobs that help us run our society the way we do today. When we start off with these bases at the beginning, they'll probably be small, just because we're getting it started, but as the infrastructure builds up, and even if we see some of those tipping points we talked about happen, where we start to have a water-based economy, then having so many people with so many skill sets going, and living, and working on the moon, that will be a game-changer. That will be a new reality. [laughs]
[00:19:14] Host: Thank you so much for joining us today, and it was an absolute pleasure to talk with you.
[00:19:18] Dr. Edwards: Thank you. Yes. Thank you for having me.
[00:19:23] Host: Christine's interview touches on a bevy of topics from how Orion will support astronauts to the moon, water extracted from lunar rocks to support colonies living on the moon, with how Mars Base Camp will enable missions to the Red Planet, to nuclear power playing an instrumental role in the future of space. And my favorite aspect about all these topics is how they captured my imagination. Looking back on those Apollo missions, our imagination is where the dream of going to the moon lived until we actually did it. I can only imagine what an exciting and momentous experience that must have been to the generation witnessing those moments. And now, our generation may have the chance to witness our dreams become a reality. With our own eyes, we will experience history being made, and at the same time, a future being laid out for generations to come.
[00:20:23] You've been listening to Dr. Christine Edwards at Lockheed Martin, and Christine is a Space Maker. Please visit this episode show notes to learn more about what you heard in this episode or the careers available at Lockheed Martin. If you enjoyed this show, please like and subscribe so others can find us and follow along for more out-of-this-world stories from Lockheed Martin Space headquartered in Littleton, Colorado. Join us on the next episode, as we introduce you to more space makers.
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