“Houston We Have a Podcast” is the official podcast of the NASA Johnson Space Center, the home of human spaceflight, stationed in Houston, Texas. We bring space right to you! On this podcast, you’ll learn from some of the brightest minds of America’s space agency as they discuss topics in engineering, science, technology and more. You’ll hear firsthand from astronauts what it’s like to launch atop a rocket, live in space and re-enter the Earth’s atmosphere. And you’ll listen in to the more human side of space as our guests tell stories of behind-the-scenes moments never heard before.

For episode 60, Dr. Peter Norsk, Senior Research Director and Element Scientist at Baylor College of Medicine based here at NASA, describes the hazard of altered gravity fields and its effects on the human body. This is part four of a five-part series on the hazards of human spaceflight. This episode was recorded on June 25, 2018.

Exploration to the Moon and Mars will expose astronauts to five known hazards of spaceflight, including gravity. To learn more, and find out what NASA’s Human Research Program is doing to protect humans in space, check out the “Hazards of Human Spaceflight” website.

Transcript

Gary Jordan (Host): Houston, we have a podcast. Welcome to the official podcast of the NASA Johnson Space Center Episode 60, “Gravity.” This is part four of our five-part series on the hazards of human space flight. I’m Gary Jordan and I’ll be your host today. So on this podcast we bring in the experts — NASA scientists, engineers, and astronauts — all to let you know the coolest information right here at NASA. So right now we’re teaming up with the Human Research Program to bring you five of the biggest hazards that humans must endure when traveling the cosmos. Today our focus is altered gravity fields with Dr. Peter Norsk, the Senior Research Director and Element Scientist at Baylor College of Medicine based here at NASA. His research has focused on how the human cardiovascular system and sodium and fluid volume regulating mechanisms are affected by changes in gravity. Don’t worry. We go over what all that means [chuckling] during today’s podcast. He’s been responsible for 10 in-flight experiments with astronauts on the shuttle and the Mir Space Station and the International Space Station. We’ll also hear clips with my conversation with Dr. Stan Love, NASA astronaut and honestly one of the smartest guys I’ve ever talked to.

Love gave his insights and personal experiences with adjusting to and from microgravity. So with no further delay, let’s go light speed and jump right ahead to our talk with Dr. Peter Norsk. Enjoy.

[ Music ]

Host: Peter, thank you so much for coming on the podcast for today.

Dr. Peter Norsk:Yeah, you’re welcome.

Host: This is an interesting topic because of course you think, you know, whenever we’re traveling in space, yes, there’s going to be changes to gravity. Obviously, you know? You know like the whole, like, zero-G, right? People floating. You see that in the movies all the time. But what’s different is how that impacts the human body and it’s pretty significant, right? So what are some of the main things that we can expect from these changes in gravity? What’s, like, the birds-eye view? What happens to the human body whenever we’re going from one place that has one gravity to another?

Dr. Peter Norsk:Well, if you entered weightlessness right now — zero-G — you would experience two things immediately. One would be a fluid shift of blood and fluid from the lower parts of the body into the upper parts because gravity is not dragging it towards your feet.

Host: Hmm.

Dr. Peter Norsk:So you will have more fullness of fluid and blood in your head and in your heart. That’s the first thing that happens within a few seconds. And then your balance organ — your inner ear organ that controls balance and perception of direction of gravity — will be totally disturbed. And a few people actually get sick very quickly. Many people it takes a little while, but in a few minutes or maybe an hour they will be very sick. It’s 75%. So those are the two acute effects of zero-G. In the inner ear you have certain weight components — small crystals that actually detect gravity — and they are affected immediately. But what the eyes are seeing and what this balance organ is sensing contradicts each other and that creates confusion in the brain and that’s what we call space sickness or motion sickness.

[ Digital Beeps ]

Host: Speaking of space sickness and feeling queasy, I chatted with NASA astronaut Stan Love about this feeling, since he experienced it himself.

[ Digital Beeping ]

Stan Love: The next thing that happens is your inner ears have little sensors in them that tell you which way down is. And you turn off the gravity and those sensors don’t know what to do. And over millennia of evolution your body has evolved the response — when I can’t tell which way down is, I’ve got to throw up. [Light laughter] So it sounds like a committee design.

[ Laughter ]

Stan Love: Not sure why that makes sense. I’ve heard a just-so story that there are certain plants that if you eat them you will die. OK? They’re plant poisons on earth. And many of those plants, before they make you die they make you dizzy. And so maybe there’s an evolutionary advantage to throwing up when you don’t know which way down is. But the sad fact of the matter is when people get to space they feel queasy.

Host: Hmm.

Stan Love: About a third of people feel so ill that they do throw up. About another third look kind of green and they keep their head rigidly in the same position and they don’t want to be upside down in the cabin because the unfamiliar environment can be provocative. We say provocative. It means you throw up.

[ Laughter ]

Stan Love: And another third claim to feel nothing.

[ Laughter ]

Stan Love: So. That, however, your body gets used to. So the first couple of days in space you’ll see people tending to be rigidly up and down in the cabin, not moving their head around a lot, maybe looking a little green, and maybe heading off to the back part of the cabin with an emesis bag. Emesis — throw-up. We had a lot of nice words for throwing up so it doesn’t sound so bad. [Laughter] And but after a couple of days that gets better. So after three, four days in space, then people are doing somersaults in the cabin and having a great old time. And that’s all perfect until you land and then the gravity turns back on [laughter] and your Valerius says, “oh, I know which way down is!” and you feel queasy again. But after a few days you feel better. Actually, after a shuttle flight they would not let us drive our cars for three days after landing because your vestibular system — that’s what they call your sense of balance — is still scrambled. And even walking around a corner in the office kind of spins your gyroid and you feel dizzy.

Host: Whoa.

Stan Love: I am told that’s how you feel if you drink six beers. I have no experience with that myself, of course [laughter]. But it’s sort of the “six beer spins” on landing day.

Host: [Laughing] OK.

[ Digital Beeping ]

Host: OK, yeah. I definitely get terrible motion sickness myself so I get it.

Dr. Peter Norsk:You may not get space sick. You may get motion sick in a car or —

Host: [Laughing] Oh. So there’s a difference?

Dr. Peter Norsk:There’s a difference. And we don’t really know why.

Host: Oh! OK. So the fluid thing — that makes a little bit of sense, right? Because we’re here on earth with one G.

Dr. Peter Norsk:Right.

Host: And our feet are down closer to the ground and have to maybe pump a little bit stronger to get towards the head because you’ve got that whole gravity thing —

Dr. Peter Norsk:Right.

Host: Pushing down on you. And we’re beings that stand erect. You know, we stand upright. Is that part of the reason why they’re experiencing that is because that gravity isn’t there anymore?

Dr. Peter Norsk:Yes.

Host: OK.

Dr. Peter Norsk:It’s simply if you have a tube of fluid, the pressure at the bottom would be higher than at the top for the reason that fluid contains weight. And that is suddenly weightless. That means that you suddenly would have an increase pressure in the top of the tube and a lower pressure in the bottom of the tube because you don’t have this gravity effect on this fluid column. That happens in the body as well. So you have more fullness in the head and it’s immediate and it lasts all throughout the mission, even for months. And that is one of our great concerns.

Host: What does that feel like? Whenever you have more fluid, does your head feel kind of puffy? Do your feet feel short of shriveled? I don’t know how would that feel.

Dr. Peter Norsk:You don’t feel anything, actually, but you look a little bit different.

Host: Really?!

Dr. Peter Norsk:A little bit of roundness in the head, more fullness around. Your face changes its shape a little bit. But some people complain of fullness in the head in particular on longer missions. But it’s not a big concern from a personal subjective point of view. It’s more of concern on a longer term, including effects on the eye and sight and vision because some astronauts do have vision changes in flight. And they do have certain changes of clinical concern in the eyes, that if you look into the eyes with certain equipment you will see changes that mimic certain diseases. So we are concerned about the fluid shift but it’s not a personal concern until you’ve been to space for several months.

Host: Which is, I mean, what we’re planning for. Right?

Dr. Peter Norsk:Exactly.

Host: If you’re talking about long-duration missions to, you know, stay on the moon.

Dr. Peter Norsk:Right, right.

Host: Long duration missions to stay on Mars. These are — especially Mars. Mars is a several yearlong mission profile.

Dr. Peter Norsk:Yes.

Host: That’s very significant.

Dr. Peter Norsk:Right.

Host: So I guess we’ll kind of start with that. You know, you’re talking about it takes some time until really they are measurable, kind of that you can really notice the effects. And you know, you can’t really notice it like you’re saying day to day. But it’s that constant exposure to microgravity and the constant exposure to these fluid shifts that may be the cause. So let’s start with vision. You’re talking about vision, these vision changes. What’s happening there? What’s happening to an astronaut’s eyes because of gravity?

Dr. Peter Norsk:Well, you have the fluid shift. And we think that during a long duration space flight this fluid shift affects vision. It takes time because it creates kind of edema. Edema means extradation of fluid from the blood stream into the tissues and that goes more slowly. But if you’re at an increased pressure in the blood vessels in the brain and the eyes you can imagine that there might be more of extradation, more of transfer fluid from the intravascular bed. I mean, from the blood stream into the tissues. That’s called edema. And the more fluid you accumulate in the tissues over time, the more concern we have. And that is actually our main hypothesis right now because —

Host: Aha.

Dr. Peter Norsk:We don’t know for sure but we are investing millions of dollars into finding out because it could be a showstopper for long duration missions if we don’t clarify what the reasons are for those particular issues. That is what we call the SANS. You know, we have acronyms for everything.

[ Laughter ]

Host: Yes, we do.

Dr. Peter Norsk:So it’s an acronym language. And SANS means the space flight associated neuro-ocular syndrome. And we are mostly concerned about it as one of the highest profile risks at NASA right now. So that’s one thing is the fluid shift but it takes time to develop the vision changes and the longer you are in space the more we are concerned. In particular we are concerned on top of that if you expose the astronauts to deep space radiation that may actually exacerbate this effect. So we are concerned about that and we don’t have the solution as of now but we are looking into certain hypotheses and certain specific equipment.

Host: You know, that’s right. We talked in a previous — this is one of the five hazards, right, that we’re doing right now. This is —

Dr. Peter Norsk:Right. Right.

Host: This is the altered gravity. We had a previous conversation with Tom Williams who mentions, you know — he was talking about the isolation aspect. But one of the major things that he kind of honed in on was the fact that you’re not just isolated to that one study. You know, that these are connected. If you’re talking about gravity, yes. Gravity has certain effects on the body but you can’t just look at the altered gravity. You’re looking at the gravity and then how radiation is impacting the effects that gravity are causing. So there is that concern, especially I’m thinking for transit. When you’re in transit from Earth to Mars, let’s say. Now you’re in this higher radiation environment. What do we know how radiation is amplifying this?

Dr. Peter Norsk:Yeah, we know very little because it’s very difficult to simulate exactly the deep space radiations on earth. We can do some simulations.

Host: Right.

Dr. Peter Norsk:Some similarities but not the same thing. And a low dose deep space radiation is different from anything we’ve been doing on Earth. So we don’t really know. But we are doing animal experiments where the animals are exposed to radiation and simulated microgravity. But again everything is simulated. So when you go into space it’s probably different. So that is some kind of knowledge we need and something that is of very high priority. But before, you know, the concerns of microgravity is you have the fluid shift as we mentioned, this motion sickness which goes away after a few days so it’s not of a big concern. But when you change gravity fields like landing on Mars, it reappears. So that is a concern is —

Host: Yes.

Dr. Peter Norsk:As you alternate on gravity and immediate effects we are concerned about. But then also you have immune effects where you attenuate the immune system. You see viral reactivation in astronauts, maybe because of stress as well.

Host: Huh.

Dr. Peter Norsk:You see changes also at the cellular level of microgravity per se which is very unexpected because these small, fluid-filled, membranous structures called cells are actually affected by microgravity as well to a degree. That could be a concern during long duration space flight. And then finally, of course, on muscle and bone you have de-loading effects which can be mitigated by extensive exercise. But these are major concerns. But everything is exacerbated and exaggerated by deep space radiation. On top of that you have isolation and confinement as indicated by Dr. Williams.

Host: Right.

Dr. Peter Norsk:So we are working — Dr. Williams and I — together much more than previously in order to try to find common pathways to mitigate those issues.

Host: Yeah. I think the bone and muscle loss is a really good one to hit on because, you know, we have those countermeasures is what we call them, right? Ways to counteract the effects which is, you know, your body is in microgravity and — I don’t know why I’m explaining it [laughing]. You should be explaining it.

Dr. Peter Norsk:No, yeah. It’s quite alright. You are doing very well.

Host: Yeah [laughing]. But you know, because you’re not — basically you’re not using it so your body is like, well, I don’t really need to put the energy towards that.

Dr. Peter Norsk:Right.

Host: So you start to lose muscle and bone mass. And that’s why they exercise a lot, especially the resistive.

Dr. Peter Norsk:Right.

Host: Is to maintain that.

Dr. Peter Norsk:Yeah.

Host: But who knows what radiation is going to do. How much more —

Dr. Peter Norsk:Right.

Host: Can we expect that you’re going to have this bone and muscle loss because of radiation?

Dr. Peter Norsk:We do know something from a simulator, animal studies in rats in particular and mice.

Host: Hmm.

Dr. Peter Norsk:And there are exaggerated — we actually have an idea about it also.

Host: Oh really?

Dr. Peter Norsk:But we, of course, don’t know that deep space will be different.

Host: Right.

Dr. Peter Norsk:But according to that you exaggerate the effects and we should be concerned about it. Now the good news is that I just listened in on a presentation I think a few weeks ago by Dr. Globus and she indicated that actually exercise would be efficient at mitigating also the radiation effects on the de-loading of Mars. So exercise, per se, may actually be the solution. But — but what happens if the exercise device breaks down?

Host: Oh yeah.

Dr. Peter Norsk:Then we need alternatives and that’s the challenge right now.

Host: Right.

Dr. Peter Norsk:And also it’s a challenge to develop an exercise equipment in that small, confined environment of the habitat as well as a [inaudible] vehicle to Mars that is as efficient as a big gym we have on ISS right now.

Host: [Laughing] Yeah.

Dr. Peter Norsk:And that is a challenge. So we have some challenges of a technical nature. But I think we can solve the muscle and skeletal unloading effect. I’m concerned about the fluid shifts effects and the eye and effects on the brain.

Host: Hmm. So the conclusion is that, you know, exercise does help and will help on that transit? We should continue to look forward to exercise but —

Dr. Peter Norsk:No, it turns out exercise helps the food, being slim, all these perfect, healthy — that’s good even in space.

Host: Really.

Dr. Peter Norsk:And it turns out also to have mitigating effects against radiation. So yes. You have to be healthy and do the right things.

Host: Yes.

Dr. Peter Norsk:But that’s why we select astronauts the rigorous way we do it and obtain the right people.

Host: That’s right.

Dr. Peter Norsk:But on top of that we need to do something else.

Host: That’s right. They’re the best of the best. You wouldn’t have to — I mean, would you have to kind of, I mean right now on the space station they have sort of a two-and-a-half-hour slot where they have dedicated to exercise.

Dr. Peter Norsk:Right.

Host: Would you probably increase that just to be safe? Or would you stick to two and a half hours?

Dr. Peter Norsk:If it were up to me I would keep that but I would do the right prescription for exercise.

Host: Hmm.

Dr. Peter Norsk:It’s not just doing exercise. It’s not just telling us to do exercise. It’s also the kind of exercise — aerobic exercise and resistance exercise in the right combination. We have actually tested that with something called the SPRINT Protocol by Dr. Lori Ploutz-Snyder who is the PI of the study. It’s just about being published. It’s been tested on ISS. We done it during [inaudible] for two weeks and 70 days and it turns out that that prescription is pretty efficient and it actually takes less time than the usual exercise being done on the ISS. So that’s an efficient way of doing it. So I’m not concerned about the time or duration of exercise every day.

Host: Ahh.

Dr. Peter Norsk:I’m more concerned about astronauts doing the right combination of different types of exercise. And but the challenge is still development of the equipment to do that and to combine the right prescription with that small exercise equipment in a very confined environment.

[ Digital Beeping ]

Host: Who knew working out was so important? I think we find ourselves sometimes coming up with excuses and blowing off exercise. But you can’t really do that in space. Though, Stan Love did and here’s what happened.

[ Digital Beeping ]

Stan Love: So as a shuttle crew member I had a few exercise sessions scheduled for me during the flight. And we had a little bicycle ergometer, they call it, and it measures how much energy you’re putting out in the bicycle. So you get on the bicycle and you do a couple turns on the bike. And they give you half an hour for that. And I just blew it off. I didn’t do my exercise.

Host: Ooh.

Stan Love: I said, I’m up here for two weeks. I’m not going to die for lack of exercise in two weeks. And I have a pile of work to do. And this exercise is not helping me do it. So I just blew off all my exercise. I do not recommend this for any space flyers. [Laughter] I got back and I had lost eight pounds — and I’m a very skinny guy to begin with. It all came off my legs.

Host: Oh.

Stan Love: And it took me two months to get my weight and strength back after just two weeks in space not exercising.

[ Digital Beeping ]

Host: Right. Yeah. Talk about constraints.

Dr. Peter Norsk:Yes.

Host: You know? You have to work out more and harder. Because that’s what SPRINT is, right? It’s more of a high-intensity exercise profile?

Dr. Peter Norsk:High-intensity exercise, aerobic exercise, as well as resistive exercise. But it doesn’t have to take such a long time.

Host: Right.

Dr. Peter Norsk:It’s just do it regularly, every day, six days a week. And then also do it in the right fashion.

Host: Alright.

Dr. Peter Norsk:Yeah.

Host: See, this is why we pick the best of the best because they have to be dedicated to that schedule. And I know I’d be exhausted after day three.

Dr. Peter Norsk:Well, we still have with the best of the best a challenge to persuade people to do the right exercise at the right time. [Laughter] And actually if you — but they are doing it.

Host: Right.

Dr. Peter Norsk:I’m not saying that. It’s just they also need to know it. And so we are defining that prescription. And then you can deviate from it but then you know what to do and you also know what the implications are if you deviate. If you have a kind of basic exercise you can deviate it to one side or the other, do less of that and more of that. But we’ll know what that means. And so that’s the important thing. But we have developed that prescription. And that’s why the exercise issue per se is not the biggest challenge right now. The biggest challenges are the other things we talked about before.

Host: Right. OK. So let’s go back to it.

Dr. Peter Norsk:Right.

Host: We hit a little bit on fluid shifts.

Dr. Peter Norsk:Yeah.

Host: But one thing that we didn’t really hit on was the whole balance thing.

Dr. Peter Norsk:Right.

Host: So what’s happening there? You know, you’re launching from space and you go into space — what is it? Eight or 12 minutes later depending on your launch vehicle. And then you’re exposed to microgravity then. At what point are you really starting to feel the effects of where am I, you know, with the loss of balance and coordination?

Dr. Peter Norsk:Well, immediately.

Host: Immediately?

Dr. Peter Norsk:Immediately. You endure parabolic flight. People get very confused.

Host: Oh, really?

Dr. Peter Norsk:And they actually vomit and feel pretty bad. Actually most, I think — almost everyone during parabolic flight takes medication against those issues. So it’s immediate. And but you have that pretty fast. But the problem is that you have to prepare the astronauts. Well, it takes about six weeks from a sensory-motor and vestibular point of view to adapt to space in movement and adapting in behavior and not hitting things and being efficient and floating through one module into the other. And then turn to lift and ride and get up and down. I mean, that takes about six weeks according to at least several astronauts that have experienced it. So it’s about a six-week adaptation. But it only takes about three, four, five days to adapt not to being sick. So these are the good news. But it takes some time.

Host: Yeah.

Dr. Peter Norsk:But then again when you land on a planet, moon, Mars, or Earth —

Host: Right.

Dr. Peter Norsk:You readapt and you have the issue immediately. When astronauts come back from six months of flight, in Kazakhstan, their balance has totally dropped and they can’t walk straight. They have to be supported. They may not be six or maybe six. Some do much better than others but they all are confused and kind of hit things or fall over. And that is of concern when you land on Mars without any reception committee and you really don’t know — or we have defined a certain temporal profile but we really don’t know how long it will take for them to being able to do the first extra behavioral activity from the landing module, for example, to the habitats. And that is a very important piece of information to know that. So we are trying to define that. We are landing on Earth but on Mars we don’t know because Mars you have only 38% of the Earth’s gravity so that hasn’t been done.

Host: [Laughing] So whatever you do, whenever you’re designing a profile for a mission to Mars, do you sort of have to build in this sort of period? Say the astronauts land successfully on Mars. There’s got to be this, at least at what we know right now, kind of a buffer time before they could actually start doing anything.

Dr. Peter Norsk:Right.

Host: Because they have to adjust.

Dr. Peter Norsk:And according to — well, it takes six days fully to adjust to the pre-flight level. But I think AI, within two or three days you’ll be able to do an EVA, I think.

Host: Really?

Dr. Peter Norsk:But actually also you can mitigate it. We have ideas as how to prepare the astronaut to be in a better shape from a sensory-motor and nervous system point of view when they land on Mars. That is actually to do what we call pre-flight adaptability training. That is, we disturb the neurovestibular system and the balance system before flying in certain fashion on a balancing platform and we disturb them visually. And when you do that repeatedly they adapt to a new environment and they are much better, much more resistant to changes in gravity. That’s one thing. And it lasts more than six months.

Host: Wow.

Dr. Peter Norsk:Well, that is what we are testing right now but we have indications that’s the case.

Host: It’s a six-month, pre-flight disturbance thing? Or is it —

Dr. Peter Norsk:No, you know, you have a six-month flight on ISS or a six-month transit flight to Mars. It’s about six months. So you can actually by prior flight adapt the astronauts and keep that adaptation for the six months it takes to Mars and then still have positive effects that mitigate. They will be less confused when they land, even based on this training on a balance plate six months before that. That’s one thing. But then also we have an idea as to during the flight exercise actually keeps them more healthy and balanced for not being too disturbed when they land.

Host: Oh, really? Aerobic or resistive or both?

Dr. Peter Norsk:But it has to be treadmill, bumping exercise and that’s difficult to do in a small vehicle. So that’s a challenge.

Host: I see.

Dr. Peter Norsk:And then also we have an idea of using a balance plate. That’s a certain plate whereby you buy straps, are pushed against them with your feet, and then you have to do certain things in order not to deviate to one side or the other. And that will keep your balance system well exercised before you land on Mars. And that is one way you could mitigate those effects. It hasn’t been tested in space. It’s still a hypothesis. But we think based on what we know that that might be a way to do it.

Host: So for how long are you doing all of these sort of disturbing exercises to sort of prepare the body?

Dr. Peter Norsk:Well, pre-flight will be maybe five to six to ten times in each astronaut.

Host: Oh!

Dr. Peter Norsk:And they will be pretty well prepared. During flight it has to be regularly on a daily basis like exercise.

Host: Oh!

Dr. Peter Norsk:But you know, treadmill exercise — if you could do it. I don’t know whether we can do it but on my assess they do treadmill exercises every day. And it’s just doing the treadmill exercise with a certain speed and so on. So that’s fine. But if you cannot do treadmill exercise we probably would have to find out how to do stimulation in a similar fashion but in a much more simpler way on the way to Mars.

Host: Yeah. Just like you were exercising your muscles to —

Dr. Peter Norsk:Yes. Yes, yes, yes. Same thing.

Host: It’s the same. You’re exercising your balance.

Dr. Peter Norsk:It will be built in in the exercise equipment, yes.

Host: OK!

Dr. Peter Norsk:So these ideas — now, you could also argue we don’t need to do anything because just after landing wait until they’re ready and then do the EVA. That’s one easy solution. I would say, I think they should be more well adapted because you never know what happens, an emergency.

Host: Right.

Dr. Peter Norsk:They may have to get out of the vehicle immediately. It would be a good thing at least to do as much as we can with exercise equipment in flight as well as pre-flight adaptability training.

Host: That’s right because if you’re landing on Mars now if you are building in sort of a buffer time, without any —

Dr. Peter Norsk:Right.

Host: Of this conditioning — now you have to think about your systems.

Dr. Peter Norsk:Yes.

Host: Because your systems have to have life support for those few days.

Dr. Peter Norsk:Exactly.

Host: They have to have enough food. Then that’s weight.

Dr. Peter Norsk:But we are working very closely with the operations people who are now also very concerned about this issue.

Host: Oh, really?

Dr. Peter Norsk:So we are trying in an operational fashion to find out the best way to mitigate the sensory motor disturbances after landing on Mars, yes.

Host: That’s right because —

Dr. Peter Norsk:Even coming back to earth, you know? If we listen to the band, we are not landing on Mars for 20 years. We actually don’t know when that will happen but it probably will be in 20 years.

Host: OK.

Dr. Peter Norsk:So you’ll be young at the time. I will be maybe gone or very old.

[ Laughter ]

Dr. Peter Norsk: But it will happen maybe in 20 years. And so before that — we don’t have the concern right now but the concern is, of course, when they land in water on Earth with the new launching systems of a commercial character. That will happen more next year, into next year. There will be launches from the US soil, by the way. That’s —

Host: Right?!

Dr. Peter Norsk:That’s fantastic.

Host: Yes!

Dr. Peter Norsk:There will be a flagship. So we will have two different competing — SpaceX and Boing — companies taking care of that. But they will land in water for one instance for SpaceX.

Host: Right.

Dr. Peter Norsk:And that is a concern that you are so disturbed balance-wise that could you get out of the vehicle? What if there is an emergency? Or on water — will you get seasick on top of that?

Host: Oh yeah.

Dr. Peter Norsk:So we probably have to mitigate that efficiently before and during flight. And we are working closely with operations to do that.

Host: That’s right. So Apollo — the Apollo capsule landed in the water. A lot of the — Gemini capsule. You know, all these different early human space flight program —

Dr. Peter Norsk:Right.

Host: The capsules landed in the water but those were short-duration missions.

Dr. Peter Norsk:Yes. And that’s a big difference.

Host: Yeah! And that’s —

Dr. Peter Norsk:And it was disturbed anyway.

Host: Right [laughing].

Dr. Peter Norsk:And you will still get — so you know, but they succeeded. But you never know what your longer duration missions [inaudible].

Host: Right. Yeah. That’s really one of the main concerns. When we’re talking about this topic of altered gravity it’s not so much the change. Maybe with the balance thing because that’s such an immediate effect but it’s really these long term things.

Dr. Peter Norsk:Yeah, the longterm things. And it turns out when you look into different physiological systems — you know, we had an idea from the shuttle days, even before that, there would be some kind of disturbance and an adaptation phase and within one or two weeks you’ll be adapted to all the systems, you know. That is not true because when you look into six months of adaptation it changes all the time for many systems. So the old-fashioned view that this would just be a small, short-term problem — that is not true. And we do not still have all of the knowledge to understand how the body adapts to six months of flight, even. Now, we are actually planning and hoping that we can do longer missions, at least from the Human Research Program point of view, because we need to know adaptation over one year at least, hopefully three years. [Laughing] But it’s difficult to do these —

Host: Whew! [Laughing] That’s a long time!

Dr. Peter Norsk:And then also see the temporal profile. When do you actually adapt and when do we know that you’re in a stable phase? We don’t know that. And it actually changes all the time when I look into specific systems.

Host: Right.

Dr. Peter Norsk:So that’s one concern. But the main concern is still, you know, we can mitigate most of the negative effects of space flight and unloading partly with exercise. And after landing we haven’t talked about all the static [inaudible] that decrease in [inaudible] when you are exposed to a gravitational field after being in microgravity. You faint, probably have a garment for that, and you drink and take salt tablets. So that seems to be the solution. So we’re not so much concerned about these issues anymore. We are concerned about what we talked about: the vision changes, the immune changes, as well as whether we can have the right food items on board and they can be maintained stable during a three-year flight back and forth to Mars.

Host: That’s right. Yes. Those humans are pretty picky and need food all the time.

Dr. Peter Norsk:Yes.

Host: So you’ve got to build that in too.

Dr. Peter Norsk:Exactly. Exactly.

Host: So that was actually interesting, that piece of information. You said we’ve already figured it out but there’s this change whenever we come back to gravity that something is happening with your blood pressure. So what’s happening and what are we doing now to successfully mitigate it?

Dr. Peter Norsk:Yeah, that’s one of my — before I came to NASA I was a researcher within the cardiovascular field. So that’s one of my favorite topics.

Host: Ah.

Dr. Peter Norsk:But it’s something that we’re not that concerned about from a health perspective. But what happens is that when you enter microgravity and you stay in microgravity, all of your blood pressure reflexes are kind of slowed down. They’re not really being stable as the same way as when you have posture changes on the ground all the time.

Host: Mmm.

Dr. Peter Norsk:You can sit upright right now without fainting because your blood pressure reflexes are efficient. And so your vessels are kind of vasoconstricted in the lower part of the body. Your heart beats a little fast. And then when you are supine that keeps you up. That keeps you away from fainting. Now, when you are in microgravity these reflexes are attenuated and so when you land on Mars your vasoconstriction reflexes in the lower part of the body is not as efficient. You have also lower blood volume and plasma volume and that may also exacerbate the negative effects. So you have a tendency of fainting or you may actually faint very easily depending on — it’s very individual based on how attenuated all these reflexes are. Now, by using a garment in the lower part of the body that prevents the fluid and the blood from being pulled downwards by gravity you can mitigate it, as well as having the astronauts drink water and take salt — tablet salt — to expand the blood volume before landing.

So that’s pretty efficient actually.

Host: Wow.

Dr. Peter Norsk:So that is what we will do when they land on Mars and also landing on Earth. We do that all the time. So that’s efficient. Even though we still see some issues, it’s a smaller thing right now. That is what they will do. Now we are more concerned about on top of that, the sensory motor disturbance we talked about.

Host: Right.

Dr. Peter Norsk:And how long that will take for them to adapt.

Host: Yeah. It’s this compounding effect.

Dr. Peter Norsk:It’s a compounding effect, yes. Exactly. Exactly.

Host: Everything sort of —

Dr. Peter Norsk:Yeah. Everything goes together.

Host: Yes! Yeah [laughing].

Dr. Peter Norsk:So that’s why we have a mostly multidisciplinary point of approach for developing countermeasures now than we did just a few years ago.

Host: Right. Yeah. And you know, like we were talking about this theme of bringing everything sort of together.

Dr. Peter Norsk:Yeah.

Host: And realizing that you can’t just focus on gravity. You’ve got to focus on all these different things working together.

Dr. Peter Norsk:Right.

Host: Because that’s the environment. That’s what’s going to happen.

Dr. Peter Norsk:Exactly. So I would say that I think we can — actually tomorrow we would from a health perspective probably be able to go to Mars and back again. What we don’t know is that on top, you know, the deep space radiation on top of everything we know about microgravity.

Host: Yeah.

Dr. Peter Norsk:I am concerned what we are doing to the astronauts when they come back and for their health in general. So that is a problem. They might be able to do it but I’m concerned about the health perspective beyond that. And also performance detriments in flight that we don’t know anything about.

Host: Right. That sort of — you know, let’s just say it’s a three-year mission profile to Mars. You know, hang out on Mars, come back. After that. You know, the longterm.

Dr. Peter Norsk:Yeah.

Host: What happens to you for the rest of your life?

Dr. Peter Norsk:And that is something we’re also concerned about, yes.

Host: Yeah.

Dr. Peter Norsk:All the former [inaudible] article has been two years.

Host: I’m guessing that’s why you want the three-year mission.

Dr. Peter Norsk:Yeah. We would definitely like to have a long mission but right now we can do six-month missions. And we may — you know, we just completed with Scott Kelly.

Host: That’s right.

Dr. Peter Norsk:A one-year mission that was very valuable but we need to repeat it in order to obtain the correct statistics from the thing that was going on with the human body for such a long duration.

Host: Yeah. A sample size of two can only get you so far, right?

Dr. Peter Norsk:Exactly. Yeah. Yeah, the Russian cosmonaut Kornienko was also one year in space. Yes.

Host: Yes, yes.

Dr. Peter Norsk:That’s right.

Host: So that was, you know, we’re looking at long-term exposure to microgravity. I kind of wanted to talk about for a little bit just what we know so far about the moon because we’re talking about —

Dr. Peter Norsk:Right.

Host: Going back to the moon again. Except maybe, you know, longer missions than we have seen in the past. But on the Apollo mission, especially. Let’s focus on that component of balance — going from microgravity on a transit to the moon and then 1/6th-G. So what do we know about — either through data or anecdotally, what do we know about that transition to the moon gravity?

Dr. Peter Norsk:Very little. So what we’ve been doing is transition from one-G to zero-G and zero-G to one-G.

Host: Right.

Dr. Peter Norsk:And we’ve been concerned about the immediate sensory motor balance effects after landing in Kazakhstan. So that’s what we’ve been issuing and having a temporal profile. We can deduct something, of course, to lower gravity but 1/6th-gravity we know very little. We know that when they landed on the moon they moved in a special fashion by kind of jumping instead of walking. But it may be actually that the stiffness of the suit at that time was actually the main reason for doing that. It’s not just the low gravity. But they did very well, actually, you know, with very little preparation because you cannot really simulate this.

Host: Right.

Dr. Peter Norsk:They simulated it on the water by having a certain kind of weight, counterweights, so that you don’t float in the water but you can simulate underwater these effects of low gravity. You can do [inaudible] but you can’t really do it the correct way. So it is something that we don’t know anything about. Now, do you have a mitigating effect of that 1/6th gravity on the sensory motor system that actually might, you know, be something whereby the astronauts may not be that concerned about sensory motor disturbances because that low gravity might be enough. We don’t know. We don’t know the threshold for when you adapt completely to a gravitational field. We don’t have the dose response curve.

[ Digital Beeping ]

Host: OK. One last cut-in from Dr. Love since we were talking about about the moon. He shared an anecdote from John Young, whose been in three gravity fields, and explores the unknown of working out on the moon.

[ Digital Beeping ]

Stan Love: Although I have it firsthand from John Young, who is one of our moon astronauts and was here at the office when I came in, that of the three gravitational fields that he experienced — 1G on the earth, zero-G in space, and 1/6th-G on the moon — the moon’s 1/6th gravity was the best.

[Laughter]

Stan Love: So it’s enough that the food stays on the plate and the poop stays in the toilet. [Laughter] But you can move around much more freely. You know, you’re incredibly strong compared to your body weight from what you’re used to on Earth. So he really liked 1/6th-G. And nobody knows what 1/3rd-G is like except from our Reduced Gravity Aircraft Research Program. I’ve been on a few 1/3rd-G flights and to my feeling in the aircraft it felt a lot like the 1/6th-G on the moon.

Host: Hmm.

Stan Love: Your body feels really floaty. You feel just immensely strong. You can jump high.

[Laughter]

Stan Love: But it’s going to be enough that the basics of life are going to be familiar to you. You could pour liquid from a pitcher into a glass, for instance. You can’t do that in microgravity. So those are sort of the G-fields we’re going to be in. Again, we have almost no experience in the intermediate gravity regime. Tons of experience on the Earth. Quite a lot of experience now in weightlessness on the ISS, and we do a lot of research there on people and things so we know how things behave in zero-G. The moon? We’ve got a tiny bit on Mars. It’s all guesswork right now.

[ Digital Beeping ]

Host: So I guess you can guess that, I mean, the fact that you’re losing muscle and bone is because you’re not really applying a lot of force. If you’re not applying force here, your muscles, like you said, they realize, oh I’m not using this. I can put my energy elsewhere. So that’s where you start losing that. But you have to kind of simulate it with exercise. So you’re still applying force on the moon and Mars. You’re still walking. You’re still sitting and you still can pour, like, water into a glass. But it’s not as much. So maybe you need it but just not as much.

Stan Love: Yeah. And we don’t know.

Host: We don’t know.

Stan Love: So we have a lot of data at 1G, a little bit at zero-G, and almost none in between.

Host: [Laughing] Right.

Stan Love: At one point we were going to have a big centrifuge on the Space Station where we could study variable gravity and understand how bodies react. Of course it wouldn’t be people but it would be mice and other animals that we can experiment with and learn how bodies react under partial gravity. But unfortunately that fell victim to budget cuts so we’re going to have to find out the hard way [chuckling].

Host: Ohhh! [Laughing] Now, the body is one thing that has to deal with all these different gravity fields. But you have to kind of design equipment that’s going to do it. Like, you already hinted at the water recycling system where, you know, calcium was introduced and, oh, we figured out the hard way that we should probably have to learn how to deal with that. But is there certain measures, when it comes to microgravity, certain ways to design technology that maybe we are learning or we can apply to deep space missions or to lunar or Mars vicinity too?

Stan Love: So most of our equipment that we have on the Space Station works in 1G and also works in zero-G.

Host: Oh!

Stan Love: So a computer, for instance, doesn’t really care where the gravity is. The printer cares [laughter] because it has to manage the paper and it’s used to having the gravity pulling the paper down in the paper tray. Now there’s no gravity pulling the paper down the paper tray. You’ve got to put a little spring or something under there.

Host: Mmhmm.

Stan Love: So that the changes in most of the equipment on board a Space Station or spacecraft, they don’t have to be big changes to go from our 1G standard environment to our zero-G or partial-G environment with the exception of things that handle liquids. So unfortunately, that means my water supply. That means my toilet. And I already joked about, you know, the poop staying in the toilet.

Host: Yeah?

Stan Love: It doesn’t always happen in zero-G.

Host: Oh.

Stan Love: And then you make sure you have gloves and a lot of extra wipes handy just in case something comes back out of that toilet. [Laughter] Things coming out of the toilet is a rare and unusual experience on Earth and, you know, you’re going to hear about that from your coworkers the next day. “Hey, you know, my toilet backed up last night.” It happens more often in microgravity because you don’t have gravity helping you. So fluid handling systems do have to be specially designed. Separating air from water is tough in microgravity.

Host: Hmm.

Stan Love: Equipment that handles that, it has poetic names like slurper bars. [Laughter] So we have slurper bars in the humidity removal system on the Space Station.

Host: Hmm.

Stan Love: You have a cold plate. The air goes by it. The excess humidity condenses out on that slurper bar and then the little holes in the slurper bar collect the water with surface tension because gravity flow doesn’t work. But if a system is not having to handle fluids, and in particular separation of gases from fluids, whatever works on the Earth works pretty well in space. And then when you turn on partial gravity the fluid problem gets easier. In fact, it gets easier enough that there are people who are advocating when we go to Mars and we might be six, eight, nine months in transit in microgravity which is complicated and difficult and our station crews are spending that long on the Space Station so we’re getting experience with it. But it’s still hard on the body. And of course if you’re going to Mars you probably want to come back and so you’ve got to go through it again.

Host: Yeah.

Stan Love: They are discussing spinning the ship for rotational gravity using the centrifugal force. And a disclaimer for physicists out there — yes, I know there’s no such thing as centrifugal force but we’re going to call it that because it’s easy to explain and if you do your math assuming it you’ll never be wrong. So that centrifugal force — forcing things to the outer part of a spinning object — can fake gravity. And then your fluid handling gets easy and the poop stays in the toilet and your body stays strong and that’s all good except if you’re spinning fast you’re going to be ill all the time. They’ve done experiments in rotating rooms with people.

Host: Ohhh.

Stan Love: And if the spin rate is about more than one revolution per minute — so sit in your chair and take 60 seconds to spin around. OK?

Host: Yeah.

Stan Love: That speed is OK. Faster than that there are people who will never get used to it.

Host: Wow!

Stan Love: And also when you pour something in rotational gravity the stream of liquid curves [laughter] in a way that you’re not quite expecting. But if you want 1G or close to 1G and you want a spin rate of less than one rev per minute, and you figure out how long your lever arm has to be to put something at the end of it and give it 1G when you’re only spinning it once a minute. It’s the size of a football stadium.

Host: Ah!

Stan Love: So your crew capsule can be pretty small and you can have 100 meters or so of cable and then a heavy object on the other end. So you can do it with cables instead of solid structures. That would save you a lot of mass.

Host: Yeah.

Stan Love: But now you’re talking about something that’s really big and unwieldy and you probably can’t launch it to spinning.

Host: Right.

Stan Love: If you build it in space you can’t build it spinning because then every time you drop a wrench, off it goes. Right?

Host: Oh yeah.

Stan Love: So you have to build it in zero-G and then spin it up. That’s going to be complicated, especially if it’s a non-rigid cable. And then even as you’re flying in space if you decide you want to turn, spinning things resist being turned. That’s why a gyroscope works. So turning your spacecraft and then probably de-spinning it because you have to separate an object to go land on the moon or Mars, it gets very complicated. And so far there are two camps: we must spin the ship, we must not spin the ship. And they’ve been going at it and we have not had any conclusive result as to which is better.

[ Laughter ]

Host: Well, it sounds — there’s problems with both, right? If you spin the ship, now you’ve got gravity but it’s going to be pretty darn hard to control, build, everything.

Stan Love: Yeah. If you don’t have gravity, you have exercise problems and fluid-handling problems.

Host: Yes.

Stan Love: And there is as yet no winner. [Laughter]

[ Digital Beeping ]

Host: That was a fun conversation with Dr. Love. I know we kind of went all over the place, though, so let’s get back to Dr. Norsk and our discussion on parabolic flight and simulated ultra-gravity on Earth.

[ Digital Beeping ]

Host: Right. You don’t know if it’s going to be —

Dr. Peter Norsk:Right.

Host: You know, you have these fluid shifts in microgravity but would you have, you know —

Dr. Peter Norsk:Yeah.

Host: Would you still have some sort of fluid shift even with a tiny bit of gravity or would that be enough to keep you kind of healthy?

Dr. Peter Norsk:Yeah. But now you ask. You know, it’s very interesting. We actually right now — we completed, I think one or two weeks ago, two or three weeks ago, I think. We completed a study where we tried to simulate effects of lunar gravity, Martian gravity, and creating a dose-response curve between gravity and effects on fluid shifts.

Host: Hmm.

Dr. Peter Norsk:And we did that during parabolic flight but you only had 20 seconds of either zero-G or lunar gravity or Martian gravity to do the study.

Host: Right.

Dr. Peter Norsk:So it’s a very short-term. But you can see fluid shifts acutely. It happens within a few seconds. And I haven’t seen any data from that study because it was completed a few weeks ago.

Host: Right.

Dr. Peter Norsk:Very complicated. An airplane has to fly in certain trajectories to create these Martian, lunar — even 1G is just flying straight and level.

Host: Right.

Dr. Peter Norsk:But also we did 3/4 of it. So we actually did open 2/5, open 5, and open 7/5-G’s in order to simulate and create a dose-response curve. And then you can deduct what the lunar and Martian gravities are. And that study is very important for seeing how much of the fluid shifts do you have because then later if you can mitigate the vision changes we see in flight induced by the fluid shift by shifting the lower body negative pressure, we would know how much we should apply in order to have an effect. And we would know whether the moon and Mars’ gravity are protected against it.

Host: Ah.

Dr. Peter Norsk:And we don’t know that yet. [Laughter] But the data is coming out right now.

Host: That would be a pretty fun flight to do some research on. So, not a fun flight for commuting or to actually travel somewhere but the plane is sort of — if you’re imagining like a sine wave.

Dr. Peter Norsk:Yes.

Host: It just sort of goes up and down and up and down.

Dr. Peter Norsk:Right. Yes. Exactly.

Host: Yeah. And at the peak, sort of, at those sine waves, that depends on the angle that you do it.

Dr. Peter Norsk:Yes. Around the top of that trajectory you are weightless.

Host: Ah, yeah. Yeah, yeah.

Dr. Peter Norsk:You have the correct understanding. Many people think it’s a kind of when it goes down or it doesn’t understand when — but actually it’s admittedly around the top because it follows exactly the trajectory when you throw something except it counteracts the air friction by the engines.

Host: Right.

Dr. Peter Norsk:So you are actually pretty efficiently weightless for that short period. But it’s preceded by and followed by high-G level because of course it drops to what you observe during the zero-G phase.

Host: Yes.

Dr. Peter Norsk:But the fluid shift is so acute that I am convinced you will get a clear cut, very good understanding of the degree of shift even within those training scenes. So that is what we have been doing. We did it about three weeks ago.

Host: OK.

Dr. Peter Norsk:And that study is very expensive [laughter] but data is coming out right now.

Host: Did you fly on it or no?

Dr. Peter Norsk:No, I did not fly on it. I have been flying in parabolic flight quite a lot in my previous life.

Host: [Laughing] Really?

Dr. Peter Norsk:Previous lives before I came to the United States, right? So —

[ Laughter ]

Dr. Peter Norsk:So but I also tried it in the United States a couple of times. I don’t get sick so that’s why it’s fun for me to do that and it’s one of the great experiences of my life. That is doing parabolic flights. [Laughter]

Host: Wait. You don’t get sick at all?

Dr. Peter Norsk:Not during parabolic flight.

Host: Oh.

Dr. Peter Norsk:But I get seasick.

Host: Oh, you get seasick? OK. You must be a master at rollercoasters, then, for sure.

Dr. Peter Norsk:Yeah, but I don’t like them anymore. I liked them when I was young [laughter] but now I’m too old for that. It’s too bumpy, you know?

Host: Oh, yeah. [Laughter] See, I did have the privilege to do a parabolic flight one time and it was definitely one of the highlights of my entire life. We did a —

Dr. Peter Norsk:To do it did you feel good?

Host: I did. Well, so we did 30 parabolic flights. And I got a little shot to kind of help me with my —

Dr. Peter Norsk:Oh, you cheated.

Host: I did cheat.

[ Laughter ]

Host: And even though I cheated I still got a little bit sick because we did 30 parabolic flights of microgravity.

Dr. Peter Norsk:Right. Right.

Host: And then we did another one of lunar, another one of Mars. And of course on the lunar I really wanted to do lunar push-ups. So I went and I went down on the ground. I did a push-up — you know, pushed myself — clapped like six times, came back to the ground. And I went up and down five, ten times or something like that. And that up and down motion with the change of gravity was enough to go, [deep exhale] huh.

Dr. Peter Norsk:You’re going to become sick, yeah. I agree.

Host: Yes [laughing].

Dr. Peter Norsk:But keep your head still. That’s it.

Host: Yeah.

Dr. Peter Norsk:In particular, during the transitions. The transitions are the worst stimuli for inducing motion sickness.

Host: Yeah.

Dr. Peter Norsk:So keep your head still and straight during the transition phases. That’s important, see? But it’s very difficult.

Host: Are these things that we actually tell astronauts whenever they’re transitioning?

Dr. Peter Norsk:Yeah.

Host: You know, just to make sure. You know, look forward.

Dr. Peter Norsk:Our specialist and lead scientist Dr. Milweski and Dr. Jacob Bloomberg from the Human Research Program are actually very good at this and they can advise the astronauts, you know, how to not move the head during certain transitions of G’s and thereby actually also doing some head movements in order to be adapted to the change. So that’s another way of doing it.

Host: Ah!

Dr. Peter Norsk:And they have certain ideas about that. So they have a full-blown list of what the astronauts should and shouldn’t do during transitions but many of those ideas have to be confirmed by really solid scientific data. So that is what we are trying to obtain.

Host: Right. And that’s what we’re looking forward to —

Dr. Peter Norsk:Right.

Host: With these exercises, right?

Dr. Peter Norsk:Yes, yes.

Host: To sort of —

Dr. Peter Norsk:Exercises, a lot of small things like head movements, how to do them, not do them. We have certain programs on laptops whereby they do certain test in order to stimulate the sensorimotor system and the moving of the eyes and things like that. So to understand and actually mitigate the effects of the desensitization of the sensorimotor system.

Host: So you might know a little bit more about this than maybe me but I just went to an amusement park because I really like rollercoasters. But I enjoy them —

Dr. Peter Norsk:I used to like them.

[ Laughter ]

Host: I still do. And I just always have. I can’t do the spinny rides, though. Anything where you’re spinning around? It’s no, just not for me. But I am getting a little bit more sensitive to it but I still enjoy them. So I tried and it kind of worked for me — it might have been a mental thing — but it was a wristband. And the wristband just sort of applied a little bit of pressure to the inside of your wrist. Is that something that actually works or is it just a mental trick?

Dr. Peter Norsk:That’s not the first time I hear about this, but I don’t know.

Host: Oh, OK! [Laughing]

Dr. Peter Norsk:And I don’t know if anyone has tested it but I wouldn’t be surprised because it doesn’t really go against the basic science. It just has to be tested and documented. If it has we would like to see the data but I haven’t heard anything from our team that this is an efficient way of mitigating but it might be. I don’t know.

Host: Yeah. Maybe I was just duped into buying one. I don’t know.

Dr. Peter Norsk:With age you become more open to these kind of things because it turns out there’s something to it. It’s just sometimes these things are also exaggerated, you know, for commercial purposes. So you have to be careful but we should test it and systematically find it. We are doing that already.

Host: Yeah.

Dr. Peter Norsk:Our team is doing it.

Host: Right.

Host: So, you know, when we’re thinking about altered gravity we were talking about some components, right? We were talking about the balance. We were talking about fluid shifts. Going back to that parabolic flight, one thing that I did want to mention was you were talking about just, you know, getting these small micro-readings, these data points during that few seconds of altered gravity but you were talking about a lower body negative pressure. Is that what you were talking about?

Dr. Peter Norsk:Well, that’s what we are testing on the ground right now but we are planning to test it in a flight. We have actually tested with the Russians the efficiency of moving fluid with lower body negative pressure from the upper part of the body to the lower part.

Host: Hmm.

Dr. Peter Norsk:So we’ve been trying to see how efficiently can we do that and how well does it work in microgravity. It has been done before. It’s on Skylab so it’s not a new thing. But we were looking at the specific measures on the eye and the fluid shift on the eye and brain and hip which hasn’t been done before. And we were looking into the efficiency of the lower body negative pressure effect and how much of the body negative pressure you would need to use.

Host: OK.

Dr. Peter Norsk:That has been done at a preliminary first step. Then we are trying to develop a countermeasure including LBNP. LBNP means lower body negative pressure. It’s an acronym, right?

Host: [Laughing] Right. Yeah, a lot of those.

Dr. Peter Norsk:So we’re using that lower body negative pressure as a mitigating procedure but we are defining how well it works.

Host: OK. Is it — I’m imaging vacuum pants. Is it vacuum pants? Or is it —

Dr. Peter Norsk:You could call it that. It’s simply, you know, you create some pressure around the lower part of the body that’s the legs and the abdomen.

Host: Hmm.

Dr. Peter Norsk:And that’s efficient to moving fluid inside the body from the head and heart downwards. But you have to be careful not to do too much because otherwise you kill the person. I mean, they will be all of a sudden they will faint —

Host: Yeah, yeah. You don’t want to drain their brain.

Dr. Peter Norsk:Yeah, you can kill people this way.

Host: Wow.

Dr. Peter Norsk:It’s something you have to be careful with.

Host: Wow. OK. Yeah. No, that’s a lot of —

Dr. Peter Norsk:But that is our main intervention right now.

Host: Ah. I see. And that’s one of those things, countermeasures, that we talk about, right?

Dr. Peter Norsk:Yeah. So when I say main, it’s a main source meaning that’s being used operationally in flight, not for this purpose but it’s our main intervention in testing for the countermeasure areas.

Host: I see, I see. OK. So what — you know, this is one of the countermeasures. We focus on —

Dr. Peter Norsk:Possibly. One of the candidate countermeasures right now.

Host: [Laughing] Candidate countermeasures.

Dr. Peter Norsk:Right, right.

Host: Yeah, because if you test it and it works, yeah, you want to implement it into procedures.

Dr. Peter Norsk:Yes.

Host: And that’s basically what we’re trying to find out now is you look at what is happening and then you define what is happening.

Dr. Peter Norsk:Right. What is happening and then we are developing countermeasures. We have very little time because of the, you know, gateway deep space mission schedule that has been defined from 2021-2022 to end of the 20s. We’re going to deep space and the vicinity of the moon and so we have schedules as for deliverables from the program. And this is one of them. And that’s why we have sped it up. We have to because at the same time we are exploring the mechanisms for the vision changes and the fluid shifts we are at the same time in parallel also trying to develop countermeasures.

Host: The countermeasures — wow.

Dr. Peter Norsk:And combining those two and doing a ground-based study, ground-based analog study, and then the flight study.

Host: OK. Yeah because, yeah, that’s a lot.

Dr. Peter Norsk:We’re in the middle of doing that right now.

Host: OK. So that would be one of the things that we would test in the lunar vicinity is based on what we know — right? We’re still learning but based on what we know we’re going to try it.

Dr. Peter Norsk:Yeah. The problem in the lunar vicinity is that these are shorter missions so that’s good.

Host: Yes.

Dr. Peter Norsk:We will look into the additional effects of deep space missions which is probably too short — four to five days — so it might take some time before we have data. We need longer missions. But on the other hand it’s also difficult to have this big lower body negative pressure equipment in this small [inaudible]. Orion is much too small. The habitat is small. So we may have to find alternative mitigating strategies.

Host: Oh wow.

Dr. Peter Norsk:So on top of that we are doing that. It will be possible in a transit [inaudible] probably also have a lower body negative pressure device. I think so but we need to know alternative strategies as well. It may also fail during a mission. So what do we then do? So we use bracelets whereby you pump the bracelets up to a certain pressure in order to trap blood in the veins in the legs thereby pulling it away from the heart. That’s one efficient way of doing it without having big equipment.

Host: Right.

Dr. Peter Norsk:It may be in combination with some lower body negative pressure. The lower body negative pressure could be mobile combined with some cuffs. We can maybe add exercise in order to trap blood more efficiently with the bracelets or the cuffs. Bracelets are the same as cuffs. I mean, all these kinds of things are being considered right now.

Host: Yeah. So looking ahead, we’ll just sort of wrap up with this. Looking ahead at some of the — based on what we know and some of the studies that we’re looking forward to, what are some of your things that you’re most excited about when we’re talking about missions going to the moon and Mars, some of the ways to implement these things.

Dr. Peter Norsk:Yeah. I’m very excited about our progress in the sense of fluid shift vision issues because we have had some breakthroughs recently. We have data from space showing that — something very surprising — we saw that what we thought would be a main problem in the fluid shift may not be. It may only be part of the problem. So that makes it maybe easier to solve if it’s correct. And the other thing is that we have for the first time it looks like we have created a bedrest analog on the ground that can induce some of the same symptoms that we have never done before. And therefore we can use that analog with a very strict bed rest. We can use that analog maybe to test some of our countermeasures and that makes it much more feasible for us to deliver it on time in the beginning of the changes. So that’s very, very exciting. So that’s what I’m very excited about. And I’m also excited about some new outcomes of our sister or brother elements. I don’t know what you —

[ Laughter ] Whereby there’s some very interesting outcomes of the effect of the dissipated radiation that you know —

Host: Yes.

Dr. Peter Norsk:Combining exactly what we are doing. It looks very promising. So I think now I’m much more optimistic about deep space vision and health than I was about a couple of years ago.

Host: OK. Wow. Well, Peter, thank you so much for coming on and sharing this broad aspect of altering gravity whenever we’re traveling. It sounds, you know — whenever you see a space movie, you know, people are going right up into space and they just think no problem. But there’s a lot of considerations and it seems like we’re making great progress. So I appreciate you coming on and explaining this for us today.

Dr. Peter Norsk:Well, thanks for inviting me. And it’s been a pleasure. Thank you.

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Host: Hey. Thanks for sticking around. So today we talked with Dr. Peter Norsk about altered gravity fields. So make sure you stick with us for one more of the five hazards of human space flight: hostile and closed environments. You can check out all five of the Hazards of Human Space Flight podcast episodes here on “Houston, We Have a Podcast” or you can go to nasa.gov/hrp who are releasing these together with some of their products that go over videos and animations that go more into depth about what we talked about here on today’s podcast. Otherwise you can go to nasa.gov/iss to figure out the latest on what we’re doing aboard the International Space Station — a lot of what we talked about on today’s discussion. On social media — Facebook, Twitter, and Instagram — you can go to the International Space Station accounts or the NASA Johnson accounts and use the hashtag #askNASA on your favorite platform to submit an idea or a suggestion for an episode that we should do here on “Houston, We Have a Podcast.” So this episode was recorded on June 25, 2018. Thanks to Alex Perryman, Pat Ryan, Bill Stafford, Mel Whiting, Bill Polaski, Judy Hayes, and Isidro Reyna.

Thanks again to Peter Norsk for coming on the show. We’ll be back next with, again, with the final episode of the Five Hazards of Human Space Flight. See you then.