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

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

In Episode 134, International Space Station Program Chief Scientist Kirt Costello talks about some of the interesting new research underway in Earth’s orbiting laboratory right now, and shares results of earlier experiments that are already making a difference for life in space and on Earth. This episode was recorded on February 3rd, 2020.

In celebration of 20 years of continuous human presence in space, check out this collection of “Houston We Have a Podcast” episodes about the International Space Station.

Transcript

Pat Ryan (Host): Houston, we have a podcast. Welcome to the official podcast of the NASA Johnson Space Center. This is Episode 134, “Sampling Science in A Lab Aloft.” I’m Pat Ryan. On this podcast we talk with scientists, engineers, astronauts and other folks about their part in America’s Space Exploration Program. Today, we’re focusing on one of the four main pillars of the Mission of the International Space Station. Flying 250 miles up above your head, give or take, there’s a science laboratory orbiting the Earth at roughly five miles a second. And there have been people on that station every single day since November of 2000, more than 19 straight years and still counting. The station was built and is operated by partners from five international space agencies, which promotes international cooperation. It has served as a destination in space encouraging commercialization to spaceflight and space research. Served as a place to learn what we need to know to return astronauts to the Moon and send them to Mars. And done it all while supporting scientific research that has meant history making achievements for science and for life here on Earth. And I don’t mean this is like a high school science class. I’m talking about cool things like the first ever sequencing of unknown microbes in space and determining how cells repair damaged DNA in space using 3D biological printers to produce usable human tissue, just for starters. Our guest today is Dr. Kirt Costello who was named the International Space Station Chief Scientist last year after serving more than three years as the Deputy Chief Scientist. Costello came to NASA in 2000 as a training instructor in the Mission Operations Directorate and worked for a time in the space stations daily operations group before moving into the Station Program Science Office in 2012. He’s also the Deputy Manager of the Station’s Research Integration Office. And I’ll get him to explain what that means as we discuss some of the cool new experiments just getting underway on orbit. And the exciting results from some of those that have gone before. Ready? Here we go!

[ Music ]

Host: Kirt Costello, what does it mean to be the Chief Scientist in the ISS Program Science Office?

Kirt Costello: Well, thanks Patrick. That’s a good question and it’s interesting from the perspective of what it means to be a program scientist. So, the ISS program is a group of managers that help bring all the wonderful experiments that we have to the space station. Those managers have the responsibility for not only assuring that the vehicles, the rockets get there with all of the payloads and that the station operates the way it should, but also in terms of the chief scientist making sure that all the science is integrated into the plan so that it can be performed on orbit. So, we serve a purpose to both prioritize all the incoming science and to provide an independent advisory role to the program manager for questions regarding the flight of that science.

Host: And because the science is an important part of the International Space Station Program but not the only part. And so, you’re helping with the integration of that science goal into the whole program.

Kirt Costello: That’s absolutely correct. I mean space station has been a great vehicle not only to showcase our engineering capabilities, being able to assemble it on orbit, this huge structure and ultimately awesome laboratory that we’ve got up there, but it’s also this international collaboration. So, as we have our NASA science, so do all of our international partners have their science and we need to integrate our roles with their science as well.

Host: If you’re focused on the science part of it, how do you characterize the overall science mission of the space station, apart from any individual experiment?

Kirt Costello: Yeah, that’s a great distinction because I really see it as a two-fold science mission. First of all, there’s the science to bring discoveries and acknowledge about how we’re going to continue and enhance our capability to explore space. And secondly there’s the National Lab Mission, which is to return benefits to the Earth. So, both of those science focuses are really the heart of what we do on space station to help with our exploration mission and then to also return new discoveries and science benefits to Earth.

Host: You point out an important point that the International Space Station is designated as a United States National Laboratory. And that’s the point of that designation?

Kirt Costello: It is and it’s also a unique National Laboratory in the fact that it is multi-disciplinary in nature. Most of our national labs are focused for one specific scientific area where the ISS is just this incredible multi-disciplinary laboratory where you have biology right next to physics in a rack onboard the space station.

Host: It is also unique in the sense that it is in space and it has very little gravity. What makes that environment attractive to researchers? Why do they want to do experiments where there is no gravity, so unlike here on Earth?

Kirt Costello: All right, so let’s talk about microgravity and what that is just to help everybody out. Of course, there is gravity in space. In fact, most of the gravity we feel on Earth is right there present on the space station, however it’s counterbalanced by the centrifugal force that we feel as we’re in orbit. So essentially, we’re in free fall the entire time. And that results in a micro gravitational force that our experiments are exposed to over time. And it’s that overtime part that’s unique about the space station. We can simulate microgravity on Earth, but we can only do it for a few seconds in the case of the drop tower where you drop an item and free fall. That’s good for about two to ten seconds. Or you could go on a parabolic flight, like some of our aircraft do and that gives you about 22 seconds of microgravity exposure. Or if you’re on a sounding rocket, one that just goes up and comes back down, you’re talking about six minutes of microgravity.

Host: Oh OK.

Kirt Costello: But on space station in orbit, we’re able to maintain that microgravity level for a very long time. And that allows us to look at processes that need to develop over a long time. For instance, wound healing. We want to know what happens to humans if they have to recover from a wound in microgravity. Does it take longer? Does it heal differently? That’s a process that takes time. And so being able to study that in analog models on the space station requires us to have a long amount of time. Growing plants is another great example. You can’t grow a plant in a couple seconds. So, we need that exposure overtime to be able to tell us what the impact of microgravity is on this organism.

Host: Both of those examples strike me as research that’s really important if you are planning to send people to keep them in space for long periods of time, like you would do if you sent them away from Earth. That’s part of what those kinds of experiments are aimed at learning more about?

Kirt Costello: That’s absolutely the exploration part of our mission. It’s how do we conduct science that’s going to help us with our exploration goals, especially for the Artemis Program. Artemis, of course, has multiple destinations, one of them being a sustainable presence on the lunar surface, the other being the eventual exploration of Mars. And those voyages are going to take a lot longer times to be able to reach those destinations and also to be able to maintain our astronaut health during that time. So, a lot of our investigations are focused on doing those tasks. We also need to look at things like technologies, how do we close the environmental control system loop. That means, how do we make sure all of the stuff that we use to keep ourselves healthy, oxygen, water —

Host: Food.

Kirt Costello: Is recyclable.

Host: Right.

Kirt Costello: And we can get back as much as possible of that. We need to close those loops to be able to support a mission to Mars over a long duration.

Host: Because we can’t bring all of those things — brand new things with us.

Kirt Costello: That’s right. As we step out across the solar system, those platforms we have get smaller and smaller. ISS is a big stepping-stone. However, our lunar base will be much smaller and Mars probably a much smaller outpost as well. So, we can’t just afford to bring all of that mass with us. We have to figure out ways to be smart and recycle most of our goods.

Host: Are there particular kinds of experiments that the International Space Station is really good at hosting, providing a place for, certain ones of the disciplines that are underway?

Kirt Costello: In terms of discoveries, I think what you’re getting at is oftentimes we’re surprised when we make discoveries in orbit about the way something behaves. And two of those fields, while we make discoveries in all of them, two of them are most prevalent. And I think that’s in fluid physics because of the way fluids behave in microgravity. In microgravity the surface tension force is the largest force you have and that has impacts on the way fluids behave in systems. And we want to know how they behave because fluids are prevalent in fuel tanks, in ecosystems, in all areas where you have to process water or other critical fluids.

Host: And eco is being environmental control.

Kirt Costello: That’s right.

Host: I think it’s a good example, in that environment, where there’s only a microscopic level of gravity, fluids, liquids don’t come down to the floor. They’re not pulled down like they are on Earth and you got to find out what they are going to do.

Kirt Costello: Exactly. And bubbles don’t separate. So, bubbles can play havoc on your systems. So, if they don’t come out or you can’t position them correctly it becomes a difficult case for your system to be able to manage that. The other area where we’re continually making discoveries is in the human system. Just exactly what extended duration microgravity exposure does to the human system. A couple of years ago we discovered what we now refer to as SANS or Spaceflight Acquired Neuro-Ocular Syndrome. SANS is a case where we’ve seen astronauts vision deteriorate after long duration stays on orbit. And this happens to some people and it doesn’t happen to everyone. And so, it’s very critical for us to understand one, if we can tell if someone is going to be susceptible to this deterioration and two, how to prepare counter measures to help them and make sure that their vision isn’t severely impacted on a long duration mission.

Host: To be clear, the impact as I’ve understood it has been — I guess the best way to say it, is fairly minimal that astronauts have their vision has degraded a bit, but it’s not like they’ve had a dramatic decrease in vision, is it?

Kirt Costello: Well, some of it can be. Most of it has been reversible, but some has not. Again, it is variable based on individual, but some of the impairment can be significant with cotton wool spots noticed in the field of vision.

Host: Oh.

Kirt Costello: And other impediments to normal 20/20 vision, which we’d like our astronauts all to have.

Host: Sure. And it’s got to be annoying to know that it happens to some and not others and you’re trying to figure out why?

Kirt Costello: Absolutely. And this is where the Human Research Program comes in and their dedicated research is really aimed at scientifically looking into the background cause for why this happens and then investigating countermeasures to help it, help tolerate it over time.

Host: Those two examples then, fluid physics and in the human system, the human life sciences, the International Space Station is trying to figure out things we need to know to support future exploration.

Kirt Costello: That’s right.

Host: Is there a running total in more than 19 years now with human crew members onboard, how many experiments have been run on the station?

Kirt Costello: I’ll say a lot, but the actual number is 2,971 investigations.

Host: Close to 3,000.

Kirt Costello: As of the end of increment 59. So close to 3,000, and that represents just over 4,000 different investigators that we’ve had participate in that research. And those investigators have come from 108 countries and regions. So just not the U.S. and its international partners. But we’ve taken in research and had coprincipal investigators and principal investigators from 108 different countries.

Host: And that’s more countries than our even partners in the space station project.

Kirt Costello: Far more.

Host: The whole world is pretty much involved.

Kirt Costello: Well, not yet. We would love to have them join but we’re getting there, we’re getting there.

Host: In the introduction I mentioned that you are also had the responsibility in the — station’s Research Integration Office. Can you explain to somebody outside the building what that means?

Kirt Costello: Sure. So, when we get a research sponsor who comes in, and that might be somebody like NASA’s Human Research Program or Space Life Biology Program come in and they sponsor research and select a [Principal Investigator] PI and give them a grant to do this research. That PI then needs to figure out how to get their experiment to the space station. They do that using payload developers and the Research Integration Office is the office here in the NASA ISS program that helps those payload developers through all the sea of bureaucracy that surrounds NASA requirements to fly your investigation on a federally owned vehicle.

Host: I can’t imagine.

Kirt Costello: So, we step in to help them with the tough stuff, the understanding the safety and vehicle requirements, making sure they’ve put together a schedule that gets them to the launch on time. And then understanding their science requirements and how that translates into performance of their investigation on orbit. So being able to help our Payloads Operations Center in Huntsville understand how to plan those requirements and have everything ready to go, so that when their investigation finally gets to the space station we can make it happen.

Host: The assistance you’re offering those people is a good thing to help people make use of the station. But I guess you’re also coordinating to make sure that all of the experiments that are being done on the station are complementary of each other.

Kirt Costello: Absolutely. We’re always checking for conflicts between investigations and also trying to understand if we can put together this integrated plan, that’s the integration in Research Integration Office, this integrated plan to get all the payloads done that we want to. The whole goal is to make the process simpler. So, a typical research investigator who would go into their lab and do their investigation doesn’t have to do a whole lot more than that. They can hand it over to a payload developer, tell them this is how we want our investigation to run, and then we can make sure that you can actually do it on the space station.

Host: So, the scientists don’t have to also be experts in bureaucracy.

Kirt Costello: In spaceflight hardware, right.

Host: You have highly trained astronauts onboard the station who are helping with these experiments. But not all of the astronauts are scientists. And I’m sure they get some training on the ground about how to run all these machines. How does having human crew members there contribute to getting these experiments accomplished?

Kirt Costello: It contributes in two ways. First off you talk about the training levels and some of our astronauts not having a science background, some do, but for those that don’t we do offer specific specialized training on the ground when it’s required. So, some instruments are very delicate. Some need to be handled in just a certain way and they’ll get that training on the ground. But improvements in the program over time have also allowed us to offer a number of other things for training our astronaut, including “Just in Time Training.” If you’ve ever gone on YouTube to try and fix your car part that just broke, and look up the video, well we can do that too and we provide those type of videos for our astronauts so that they can view it right before they perform the operation and get a refresher, a mental refresher and know exactly visually how to perform the investigation. We’ve also made improvements in our space to ground capability for communications. And what this does is allow us to have our investigators tie in real time to their operations onboard, especially if they are complex. And that gives the astronaut a path of communications to call back down and talk about what’s going on in the experiment, especially if they see anything that looks out of place.

Host: So, the astronauts on the station are talking directly to the scientist.

Kirt Costello: That’s right. And that’s happening more and more now that we’ve improved the communication links. What that does is it not only helps you avoid any errors in the experiment going off as planned, but the astronauts are also eyes and ears on what’s happening real time. And they have a unique perspective and are able to pass that back to the PI. Sometimes we see things that are out of the ordinary and they’re discoveries. And that’s a great thing that happens, especially when it gets relayed directly to the PI. They know they’re on to something. They can investigate further.

Host: And it gets them all excited then that something they didn’t expect is going on.

Kirt Costello: That’s right.

Host: Excellent. Let’s talk about some specific experiments. What’s going on now that you would dazzle people with, that I would call kind of “Gee-whizzy,” what’s happening up there?

Kirt Costello: Well, I think one of the experiments — or it’s not one, it’s actually multiple experiments that gets people’s imagination going are collaboration with NIH NCATS. So, that’s the [National Institute of Health] and a [National Center for Advancing Translational Science]. What they’re trying to do is understand how we get therapies or treatments through the process of certification faster than the traditional process, which takes years and years and has a drug mortality rate of a huge percentage. So very few, about 12 percent of those new investigational drugs actually make it through testing. So NCATS has the role of trying to figure out ways that we can go through this process quicker and better. They partnered up with the National Laboratory to issue the “Tissue Chips and Space Challenge.” And tissue chips are, in this case, microscopic chips or small volume chips that allow for the growth of tissues and small organoids.

Host: You’re talking about computer chips?

Kirt Costello: Not computer chips. They’re only referred to as chips because they’re about the same size and shape as a computer chip. But they’re really microfluidic vessels. And in some of the chambers you’ll have cells laid down and those cells can form into tissues and then you vascularize them, you are able to send them blood and nutrients and grow them on orbit. That allows us to look at the changes that occur in these small biological systems and may lead to things like personalized medicine. What it has led to, as part of an ISS investigation, is the miniaturization of these systems. So most of these systems on the ground require architecture that’s about the size of a refrigerator if you can think about that.

Host: OK.

Kirt Costello: So, what we refer to as “rack-size” on orbit. And what we’ve been able to do is miniaturize those systems through working with a number of our payload developers into systems that now fit within say a bread machine. So much smaller, much more simpler and autonomous for investigators to use. And we’re seeing real progress being made with several of these systems being tested out on orbit. Another unique thing about these grants is all of the researchers in the NIH NCATS grants got to fly two missions. So, for most of them the first mission is complete and now they’re learning from that. They’re learning how did their system work, was it validated? And now they are going to go back and re-fly their systems and this time include treatments for disease states for some of these tissues.

Host: Explain what we mean by “disease states.”

Kirt Costello: Well, for instance, one of the tissues is bone and knee synovium tissue. So that’s the cartridge in your knee joints. And it’s there to do an investigation for arthritis, in this case injury-induced arthritis. So, the arthritic feelings you might have after a severe injury to your knee. We’ll be looking at that and now in this next flight we’ll be testing a drug, an investigational drug to look at whether or not it treats that on orbit. A lot of these investigations are really being done because we know the microgravity environment is a stressor on biological systems. And because we can do multiple systems in these tissue on chips systems, we can test and evaluate how the spaceflight is affecting the tissues. And we can do that through molecular testing on these tissues, DNA testing and proteomics, metabolomics, other types of measurements that now allow us to see a little bit better how microgravity is really affecting the system.

Host: I’m curious, when you say that microgravity is a stressor on biological systems, because in my mind it seems like, well if I’m floating I’m pretty relaxed and everything is cool. In what way are you seeing that that causes stress on a person or part of a person?

Kirt Costello: I guess the best way to put it is we don’t typically float all the time. So, we were all born and raised, and evolution developed us over billions of years in a 1-G field.

Host: Right.

Kirt Costello: So being in a gravitational potential that’s different from that does act as a stressor. Our cells really don’t understand what they need to do. Water doesn’t flow the same way that we would expect it, and of course all biological life depends on water. So, in partiality it’s just that fluid exchange problem again and trying to understand how that impacts our cells. But it does create what appears to be a stress state. And that’s also something we’ve noticed through years of research in the human research portfolio is that while astronauts are affected a certain way on orbit, typically when they return to Earth after weeks, to a few months in some cases, they recover. So that stressor field has gone away and they’re able to make the transition back to health.

Host: There’s a couple of other experiments that have to do with human bodies or body parts that I saw that I wanted to ask you about. One called Printing Biological Tissues. You are really 3D printing organ-like tissues?

Kirt Costello: That’s right. So Techshot is a company that has partnered with NASA to fly their bio fabrication facility. This is a 3D printer for human cells. And in terms of human cells, they can arrange them into larger structures, organoids, tissues that are meant for implementation or —

Host: Did you say, “Organoids?”

Kirt Costello: Organoids, yes, small organ. So, what they do is they typically take a bio ink, which is made up of stem cells or seed cells and print it pretty much like you would see in your typical 3D printer, however because we’re no longer in a gravitational field you can print structures that are much more delicate and would collapse under their own weight if done on Earth. On Earth, technicians have figured out how to do this as well, but they oftentimes have to use fillers or templates or structure to keep the cells in the position. And those oftentimes can be somewhat toxic to the cells that they’re trying to grow. And you have to figure out later on how to get rid of them. So printing 3D biostructures in space has the advantage of not having to require that.

Host: OK.

Kirt Costello: Or being able to print with less viscus inks and that’s key to keeping these cells healthy and helping them grow into the organoids or tissues that you want to develop.

Host: And they would be able to maintain their structure and not collapse on themselves if they were brought back to Earth?

Kirt Costello: Right. A lot of times they’re frozen for return because, again, this is just the initial stages of understanding the quality of these structures, the bio hardiness of them, if you will, and understanding if they are a better tissue substitute. In the long-term we’d have to find solutions for how to safely transport them back to the Earth, but maybe that’s something Sierra, Nevada might be able to help us with in the future. They have a very G-friendly landing profile.

Host: And maybe if you’re creating these in space you don’t need to bring them back to Earth, you need to use them in space on some mission of the future.

Kirt Costello: Potentially, far in the future.

Host: Far in the future.

Kirt Costello: We might be looking at that. But this is really an investigation that’s coming out of the commercial sector and looking at ways to help develop the lower Earth orbit environment as a commercial marketplace. And this may be a potential use for that in the future.

Host: I was going to give you the opportunity to expound on that because not all the research being done on the station is from academia. A lot of it is coming from commercial companies.

Kirt Costello: That’s right. So, we have a large contingent of investigations that are being driven through commercial partnership. Those are looking at ways to help establish Leo as a place where we want to enhance the marketplace capability for commercial providers. They may be coming in with materials processing-type solution that works better at microgravity, for instance 3D printing, very delicate structures like for micro satellites or microstructures to assemble on orbit. They may be looking at materials development. So, in space you don’t have buoyancy driven convection. Hot things don’t rise over colder things, so a lot of times that can lead to discoveries when you’re doing material science, especially involved around melting or processing of materials. So there have been advances where people look at new materials in space and how to form stronger and more advantageous materials using microgravity as one of the factors.

Host: I noticed another experiment in which they’re working to create artificial retinal implants, is coming out of the some portion of the human research too.

Kirt Costello: That’s right. That’s — well, not really human research at this point, but that is another company called Lambdavision and they’re pulling together essentially 3D printing of these retinal tissue patches that they’ve developed. And again, they’re able to do it better on orbit because you don’t have gravity making the cells sag towards the bottom of the container. That allows you to print these patches in a much more uniform way and I don’t believe they’re in clinical testing yet, but their goal is to one day be able to print these patches and help with retinal myopathy and other diseases of the eye.

Host: Cool. Let me change the focus. Instead of talking about human research talk about technology. There’s an experiment called “Astrobee” with three free flying robots. Why did I write that? Three free flying robots to help future astronauts do work, right?

Kirt Costello: Mm-hmm. Astrobee is actually, I guess, the second generation of free flying robots that we’ve had onboard the station. The first-generation NASA had was our [Synchronized Position Hold, Engage, Reorient, Experimental Satellites] Spheres investigation. So, Spheres you may have even seen in press photos before. They were some brightly colored balls that flew around using compressed carbon dioxide. And we had many different uses for them. Some to test out technologies about docking and fluid mechanics for fuel tanks and things like that. But they were also used as an educational demonstrator and we had high school students and middle school students in programming challenges, the maneuvers of these spheres.

Host: And then there was competitions in which the astronauts helped position these soccer balls to allow the students to drive them.

Kirt Costello: Right. And the students code was driving them and usually the winner was the one who got there first or got all the objectives right. Astrobee is the second generation of that.

Host: OK.

Kirt Costello: But instead of using carbon dioxide jets to fly around the space station, carbon dioxide is not great for our astronauts, of course we have to remove it after we use it. They use adducted fan technology. So those are just fans with louvers that help them position and move them around using air.

Host: So, they’re just pushing air to maneuver?

Kirt Costello: Right. So, they’re very much like the spheres. They’re programmable, they have different tasks and duties. They also have an interface panel for the astronauts and they have a little perching arm, a cute little robot claw that can reach out and attach itself to various fixtures on the space station. And that’s particularly helpful because it allows the units to essentially stare over a crew member’s shoulder to help them with tasks to be able to act as an audio/video interface. They also have [Radio-frequency identification] RFID readers in them. So, it’s possible to use the Astrobee to move around station and look for certain RFID tags, which is great because it may save our crew members time from having to look for something that may have gotten lost in orbit.

Host: Cool. And I guess, they would allow people on Earth or somewhere else to be looking at what the astronaut on the station in this case, is doing, to assist them.

Kirt Costello: That is the goal eventually. And of course, all of this is done in trying to enhance our autonomous capability. Someday we won’t be as close as the space station is to us. We won’t have a comm link–

Host: — As close to Earth.

Kirt Costello: Right, we won’t have a comm link that gets us to space station in less than a second or whatever the vehicle is, and the crew may need more onboard assistance. So, these types of assistance are valuable in testing out our future autonomous capability.

Host: I was taken by another experiment called BioRock, looking into interactions of liquids, rocks and microorganisms to improve mining materials?

Kirt Costello: Yeah, this one is pretty far out there but it is looking at biological microorganisms’ ability to breakdown and isolate certain minerals from rocks. So biomining is becoming more prevalent in certain areas and understanding how that could be used in a microgravity environment say for processing asteroids or something, in the far future is what this investigation is really going after.

Host: Another experiment that’s had a bunch of different generations is rodent research. You’re evaluating physiological, muscular and skeletal effects of the microgravity environment, using rodents as test subjects, right?

Kirt Costello: That’s right. So, we’ve had 60 investigations I think to date in the area of rodent research on the ISS. That includes all of our tissue sharing program, people who get samples after the rodent missions. But a lot of them are looking at drug interactions — and therapies for muscle loss, bone loss, common side effects of flying in space that we know about. And others are really looking at setting out an understanding of how a rodent model, an animal model commonly used to precursor human research here on Earth can be used and applied as a zero G model for human health. So, a lot of those investigations are looking at treatments and other investigations are really looking at solidifying the links between the rodent research model and the human research model.

Host: So that’s extending what’s being done in lots of different kinds of science on Earth now in that environment.

Kirt Costello: That’s right.

Host: We’ve been talking about experiments going on inside laboratory modules. There are experiments that are going on — the outside of the station too that the crew members don’t have hands on interaction with. And one of the biggest ones that we’ve just heard a lot about is the alpha magnetic spectrometer, Luca Parmitano and Drew Morgan recently completed some spacewalks in order to get that experiment back in operation. Talk about what the AMS is doing.

Kirt Costello: So, the AMS is a particle detector outside external to the space station. It contains the largest permanent magnet that we’ve flown to date.

Host: How large is it?

Kirt Costello: Very large. I’ll go with “very.” It has provided us billions of data points now.

Host: With a “B” billions.

Kirt Costello: Billions with a “B.” And its ultimate goal is to understand the energy regime of high energy cosmic rays and how those models either account for or don’t account for the presence of dark matter and dark energy. It’s an amazing instrument. It was meant to last for three years and complete its mission in that time. However now we’re eight years in and as you said, we just conducted an amazing set of EVAs’ to repair the instrument, which it lost some cooling capabilities over the years. And it is now back on track to be up and operating and continue its mission, which is to really help us zero in on the models that we use to understand cosmology and whether or not dark energy, dark matter exist and how they might impact those models.

Host: To try to prove dark matter?

Kirt Costello: Well, as Sam Ting puts it, Dr. Ting says, “I can only disprove dark matter.” And that’s based on the way theories work. So, the cosmic rays being collected tell us something about the energy spectrum. And the theories behind that can either account for dark matter being in the equation or not. So, if he gets data, he can maybe show it’s not there. But he can’t show specifically what dark matter is, not just from the data collected there.

Host: Based on billions.

Kirt Costello: Based on billions and billions of data points. I think 130 billion last count.

Host: 130 billion. There’s another experiment on the outside called [ECOsystem Spaceborne Thermal Radiometer Experiment on Space Station] ECOSTRESS that is from 250 miles up is telling us something about water in plants on the ground.

Kirt Costello: That’s right. It’s looking at Earth’s forest and specifically those in the Northern Hemisphere over North America and really trying to understand the stress levels of plants as they go through the growth season. And understanding throughout the day, which is unique to the ISS orbit, the capability to do this at different times in the day. To understand throughout the day what’s happening, where’s the water going, where are the plants stressed, where are they not? This is a great indicator and for the water cycle on Earth and understanding how that works. And also, for helping us to develop models of how temperature and climate affect the stress in our crops and forests.

Host: I just think it’s cool that we can tell all that from an instrument that’s in orbit 250 miles away.

Kirt Costello: It’s absolutely cool and it’s made possible by the fact that you have this huge ISS platform as a host for these external investigations. Typically, an external investigation would cost much, much more because you have to pay for a rocket to launch it. You have to pay for a power bus, a data bus, a thermal bus, all to service it. Well, those services are provided by the International Space Station and the Space Mission Directorate Payloads at NASA that fly to ISS can take advantage of that. So, they can cut that part of their development out of the system.

Host: There’s been laboratory research going on in the International Space Station with crew members there from more than 19 years now. I got to believe that some of those early scientists have had time to crunch their data and figure out what they learned from their experiment. Give me an example or two of what International Space Station experiments have learned, have taught us so far.

Kirt Costello: Yeah, some of the biggest discoveries that have gone on to really provide benefits for us have been in the area of bone loss, of course our astronauts originally on orbit suffer quite a bit of bone loss. It was equivalent to osteoporotic women at 70 years of age. At an advanced age. Well, that was until we learned how to counter act it. And part of that learning process through the Human Research Program helped us zero in on two things — resistive exercise and vitamin D uptake. So, the vitamin D uptake itself went into the [United States Department of Agriculture] USDA recommendations for people trying to combat osteoporosis and bone related decay. So that’s a great example of one area of research that’s really paid off in dividends. Another area that we’re hoping to be very beneficial is in the continued investigation of cool flames.

Host: Cool flames?

Kirt Costello: Cool flames, yeah. So, fires can burn hot or they can burn cool. And this is a phenomenon that we see on Earth sometimes. If you’ve ever had an old car engine that knocks when you try and shut it off or it would rumble a bit and it won’t stop, well that process is evidence of cool flames going on, there combustion occurring at a much lower temperature. But on Earth we can only observe it for a very short fraction of a time. And we can’t do it in a stable environment. On ISS, within the combustion integrated rack, we were able to perform experiments that zeroed in on that cool flame capability and we’re able to observe it over time. And again, because we don’t have buoyancy driven convection you don’t have the turbulence surrounding the flames, we can study it in much more detail. And the hope is that these observations will allow us to refine our models and make more efficient engines and more efficient fuel burning processes here on Earth.

Host: We’ve been talking about experiments that are going on today and results of previous research. Look to the future for me. Tell me about some of the things you see coming, experiments that are going to be on the International Space Station that you’re excited about.

Kirt Costello: OK, so one of the investigations I’m very excited about, it’s also just been through a repair. So, while our crew members were taking EVAs to go fix the AMS02 investigation outside, they were also preparing to do an upgrade to one of our investigations inside. And that’s to a very exciting experiment called the Cold Atom Lab. So cold atoms, we also refer to Bose-Einstein condensate, are another state of matter where you get it to very low temperatures, near absolute zero, the wave packet of an atom becomes significantly larger, in fact macroscopic, so we can start observing the behavior of these things. We have many teams selected to do investigation on the Cold Atom Lab right now. In fact, a three team members with Nobel Laureate’s on them have been waiting to conduct their research and the recent upgrades to the system called Science Module 3 are allowing us to incorporate their new research into the laboratory device itself. So, CAL is an amazing instrument. It’s probably one of the most complex instruments we’ve got on orbit, another miracle of miniaturization where we’ve taken a whole laboratory bench back in the lab and compressed into about a half a rack’s worth of space. And we need microgravity because on Earth to get to these cold atom states you have to strongly trap the atoms. And gravity pushes the atoms into that trap, which exchanges energy with them and raises their temperature. So, to get to extremely cold temperatures, near absolute zero, we have to make very weak traps. And if you remove gravity you remove one of the impediments to getting to those very cold temperatures. Now, the stuff, the investigations that our teams are going to look at are really amazing. They’re going to look at weak interactions between different types of atoms, in this case rubidium and potassium. To date we’ve had cold atoms made of rubidium. And now the Science Module 3 should enhance our capability to do potassium atoms. So, you can do tests of Einstein’s equivalence principle and other things, where you drop two atoms of different mass and see which one really falls faster or not. So, they’ll be conducting those types of investigations. They’ll also be looking at a process known as atom interferometry. So, like I said, atoms behave as waves. There’s a wave particle duality to atoms that we know about from quantum mechanics. And what that means is when you get very cold atoms you can start having their wave packets interact. And this is the same way that light may interact in a light-based interferometer. Except now we’re talking about matter interacting this way.

Host: Wow.

Kirt Costello: What this allows for is some incredibly precise measurements of things such as gravity, mass, and other capabilities that we would be interested in for navigation purposes in the future. So, we’ll be looking at doing some initial tests into atom interferometry and how to create these next generation devices that may someday show up in your cell phone, we don’t know.

Host: But you’re saying that the precision of that measurement can translate into better instruments?

Kirt Costello: Right, because it’s being done on the atomic level. Right. So that experiment is one that’s also been on hold while we replace this size Module 3, but I’m very excited to see it starting up again.

Host: There’s so much of it that’s exciting, even to people like me who are not scientists, but it’s still the prospect of the reality of what’s being done, as well as the prospect of things to come. Very exciting to hear about and I hope we’ll get a chance to do this again.

Kirt Costello: Mm-hmm.

Host: Kirt Costello, thank you very much.

Kirt Costello: Thank you.

[ Music ]

Host: We’d like to say that the International Space Station has as much room inside it as a five-bedroom house. That’s huge, right? Well, I think the only way that that image could be made to seem small is to realize that this big house holds all the science hardware needed to support laboratory research on biology and biotechnology, and physical science, and technology development and demonstration and human life sciences and Earth and space sciences. Plus, a television studio to accommodate your educational and cultural outreach activities, as well as storage space and room to sleep six, plus utilities and a nice big picture window with a one of a kind view. The space station partner agencies have packed that five-bedroom house with the hardware and laboratory assistance who are necessary to do work in all of those scientific disciplines. You can keep up with the latest on the International Space Station, science-wise and otherwise at NASA.gov/station. And for students, we have a special heads-up about space station science, or maybe more accurately your science on the station. To celebrate 20 years of continuous human presence living and working in space, our STEM on Station team here at the Johnson Space Center will fund five student designed payloads to fly to and return from the space station. It’s part of the Student Payload Opportunity with Citizen Science Program. We love acronyms. That’s SPOCS, S-P-O-C-S. For more information, and to submit proposals, make sure to check out www.NASA.gov/STEMonstation/SPOCS. Mark it on your calendars because submissions are due by 5:00 P.M. Eastern time on March 27th, 2020, the end of this month. I’ll also remind you that you can go online to keep up with all things NASA at NASA.gov. You can follow us on Facebook, Twitter and Instagram at all the NASA JSC accounts. When you go to those sites use the hashtag #AskNASA to submit a question or suggest a topic for us. Remember to say it’s for, “Houston, We Have a Podcast.” You can find the full catalog of all of our episodes by going to NASA.gov/podcasts and scrolling to our name. You can also find all the other exciting NASA podcasts right there at the same spot you find us. NASA.gov/podcast. Very convenient. This episode was recorded on February 3rd, 2020. Thanks to Alex Perryman, Gary Jordan, Norah Moran and Belinda Pulido for their help with the production and to Jennifer Buchli, David Brady, Brian Dansberry, Rachel Berry, and Leigh Anne Rogers in the International Space Station Program Science Office for helping pull the pieces together. And thanks to our guest, International Space Station Chief Scientist, Kirt Costello. We’ll be back next week.