A conversation with John Hogan, an environmental scientist at the bioengineering branch at NASA’s Ames Research Center.

Transcript

Abby Tabor:You’re listening to NASA in Silicon Valley, episode 71. This is Abby Tabor, doing my best Matthew Buffington impression because your usual host has been called away to NASA Headquarters on urgent business. But, I have Frank Tavares here with me.

Frank Tavares: Hello!

Abby Tabor:Hello, Frank. So tell us who our guest is this week!

Frank Tavares: Well, today we have John Hogan, an environmental scientist in the bioengineering branch here at NASA Ames.

Abby Tabor:What does he do? Tell us what we’re going to learn.

Frank Tavares:So John works on life support systems for environments like the International Space Station, and basically thinks about how can we be energy efficient in these spaces, how can we reuse and recycle, to some extent, the materials we produce there. How can we take excess waste, even just in the form of the carbon dioxide we breathe out, and turn that into something like oxygen that we can reuse. And this all happens basically on the molecular scale, which is really important not just for space exploration and space travel, but also for an Earth that’s being increasingly depleted of resources like fossil fuels.

Abby Tabor:Yeah, that’s so interesting. On the space station, even our breath is a waste product, right, that they have to deal with.

Frank Tavares:Exactly.

Abby Tabor:Interesting. Okay, well as Matt likes to remind us, we are a NASA podcast but we’re not the only NASA podcast! Our friends at the Johnson Space Center have a podcast called Houston We Have a Podcast. We actually just did a joint episode with them, where we talked about the experiments that we launch to the space station, and how the astronauts work with them. And also NASA Headquarters has a new podcast called Gravity Assist that will take you on a virtual tour of the solar system and beyond. So before we jump into our episode, one reminder, we have a phone number! You can call with any questions or comment, leave us a message, and we’ll see how to add that to a future episode. That number is (650) 604-1400. Otherwise, you can do the same on social media, where we use the hashtag #NASASiliconValley. But for today…

Frank Tavares:Let’s hear from John Hogan.

[Host]

Matthew Buffington (Host): How did you end up at NASA? How did you end up in Silicon Valley?

John Hogan: That’s a little bit of a long story.

Host: Normally it is.

John Hogan: Yeah. So, I can trace a little bit back to when I was a kid.

Host: Uh-huh.

John Hogan: There was a time, I think it was probably 10th grade, I had a teacher who was teaching astronomy and it really piqued my interest. I remember having my own notebook, that I was drawing out constellations, and I actually made a telescope stand.

Host: Oh, really?

John Hogan: And saved — I didn’t have much money, but I had allowance and worked, and bought a cheap telescope, and built the stand with the angle of inclination also correct. I went out and started using it and actually one of the first things I saw was Saturn, with the rings around it. And I ran in and got my father, he came running out, and we all got to see Saturn.

Host: This is in high school?

John Hogan: Yeah, probably in the 9th grade.

Host: Okay, nice.

John Hogan: Probably 9th grade. But nothing much happened of that, and I actually went to school for environmental sciences. So, I’m an environmental scientist by training. I got all my degrees at Rutgers University, and actually became a research faculty there.

Host: Oh, wow.

John Hogan: But working with NASA, after I was done with my PhD. And I was working in biological waste treatment, of all things. NASA presented a grant-backed thing the NSCORT, NASA Specialized Center for Research and Training. It was a five-year program that they would give to a university, and we had multiple universities associated with it. And it was for bio-regenerative life support.

So, we looked at all the different types of life support technologies that could be biological in nature to recycle water back to drinking water, pull carbon dioxide back into oxygen or products, how to treat waste and bring waste back into products that you can reuse. How to grow plants, systems analysis, putting it all together.

Host: Super useful if you’re living on a space station.

John Hogan: Exactly.

Host: Or going to Mars or anything.

John Hogan: Or on Earth.

Host: Really, because that’s the thing that I think most people don’t think of. It’s like, we’re making life on ISS, on the International Space Station, has to be very efficient.

John Hogan: Yes.

Host: And I imagine there’s got to be tons of lessons learned for, you know, you think of countries or other places where maybe water is hard to come by.

John Hogan: Yes, working for NASA actually changed my quite a bit as an environmental scientist. I was used to working in unit processes. You know, this hazardous waste system, or this composting system, a wastewater treatment system. And what came in and what came out were kind of blind to you beyond that scope, right?

Host: Okay.

John Hogan: You had a really narrow focus. And I started working in all these different areas and putting it all into a very integrated system, which, once you realize you’re in a spaceship and it’s much smaller, my output becomes your input and vice versa.

Host: Okay.

John Hogan: And so it matters, amazingly, much more, at least seemingly, in a spacecraft than it does here on Earth. But as you stand back and start to look at the Earth, and I know it’s an old metaphor, spaceship Earth, but in reality, life support systems are critical wherever we’re going to be in the universe at any point in time. So, no matter where you are you’re reliant on your life support systems.

For planet Earth, we have a tremendous set of ecosystem services. The whole system. From the sun powering us, to all the physical, chemical, and biological processes that go on here on Earth, always keeping us alive, and they’re all our life support systems. And so we try to mimic those. We try to take what’s going on there and bring up mostly technical versions of those and put it in the space station.

But what I learned was that your life support systems, the Earth, really, has life support systems which are invisible.

Host: Yeah, it’s always there around us. It evolved with us.

John Hogan: Yeah, we call it a tree, we call it a stream, we call it a bird, we call it a bacteria.

Host: You don’t think how it’s converting sunlight into, or carbon dioxide into oxygen.

John Hogan: Exactly. And they’re operating 24/7, and every component of the Earth has its role that it’s playing right now. And so when you build a system like ISS, or going on to a Mars mission, you’re essentially trying to learn what’s going on there. It’s highly efficient. It’s remarkably beautiful too, right? How do you bring that into a Mars system and maintain yourself in a reasonable and smart way ad infinitum? You know, not just for a couple months, but, you know, just move on.

Host: Yeah. I think we all have the thoughts, or we have it in our brains, about being energy efficient. You know, you use a certain kind of plug, or a certain kind of power supply. A special TV that has the little energy thing. You know, it’s like we’re creating energy, we want to be more efficient, save money. But that can fall into being efficient with how we use water, being efficient of the air that we’re breathing, that we’re not wasting any precious molecules, where it is a limited resource in space.

John Hogan: Right, exactly. When we breathe, we produce about a kilogram of carbon dioxide per person per day.

Host: Okay.

John Hogan: So, we’re going to be doing that here on Earth or anywhere we go. How much more we produce is a function of all the other processes that we do and understanding the balance, either within a spacecraft like ISS, or an Earth spacecraft, is essential on a systems level. Understanding those balances.

Host: So, you started off doing, as an environmental scientist, you’re researching and you’re doing this stuff for NASA. At what point does it turn towards, like, oh hey, you started picking up the NASA.gov email address?

John Hogan: Right. I’d been working with NASA for about six, almost seven, years at Rutgers. I really liked what I was learning at NASA. We got to approach things in a much more integrated way than I was able to in environmental sciences. I got to know the people and really liked everything, and sort of developed an opportunity, a couple places, but I wanted the one out here names the most, and came through.

I was actually working on a, of all things, a database project, which sounds a little unusual. But when you’re putting together requirements for systems, and building systems, and developing technologies, and gathering all the information, if you want to integrate that into a larger system, you need all the information to be captured well.

And it was just sort of this little sidebar from all the other stuff that we were doing when we were doing systems analysis, that we needed this information, we needed to capture it from all the people who were generating it. And so, it was an old project. They called it OPUS, online project information system. It was a database that we just collected — We ended up going to all the different areas of life support and creating a system that could grab that data.

Host: What kind of data is this? Is this the oxygen in the room, or what exactly is that?

John Hogan: For the life support processes that we were interested in, it was more like if, let’s say that you had a waste water treatment system that you were developing. What were the inputs that you were putting into it? What were the components of that? How much energy did it use, the mass, power, volume? Any reliability data, any testing data that you had.

We’re trying to gather it all because there are other people who are pure systems analysts, who do mission planning, and they start to design these spacecraft and need to say, we’re going to take this piece of equipment and this piece of equipment and start putting them together. And they form big spaghetti diagrams of, this comes out of this one and goes into this one. And make a model of that and start running the models and seeing, does this work or not. For them to get good data is absolutely critical for these models to be of use.

Host: Yeah. If you don’t have that, and inconsistent data, how are you going to improve it?

John Hogan: Exactly.

Host: You wouldn’t even know what’s wrong.

John Hogan: Right. And so, that was what got me here to Ames, but I had been a waste treatment person for quite a while, wastewater treatment, and so I also work with those groups, incidentally. So, I’ve been doing that for a long period of time as well. And I’ve done a little bit of everything actually, here. It sort of reflects what I was doing at the NSCORT too, which what a little bit of everything.

Because we have done a lot in the waste realm, which is either just [safening], just trying to find a way to take the waste out of the system. And there’s systems that have been worked on, like the compaction system, and heat melt compactor, but also ways of oxidizing the waste. You know, thermally processing it, turning it back into carbon dioxide and water and coming up with an ash. So, there’s number systems like that.

I also — I’ll tell you a little funny story. We worked on a toilet concept at one point.

Host: Okay, all great conversations start with, I was working on a toilet concept.

John Hogan: Right. [Laughter] So, when you are in the microgravity environment, going to the bathroom is very different. There’s an awful lot out there already. I won’t go into the details.

Host: One can imagine the complications of zero gravity.

John Hogan: Right. When they were going back, and this was a little while ago now, when I first came out. I came out in 2004. They were going back to more of an Apollo type of design instead of the shuttle. And so it was going to be volume constrained again, really small. And so, in the Apollo missions, they didn’t have a toilet. They actually used bags that you essentially adhered to your rear end.

Host: Really?

John Hogan: Yes.

Host: Okay.

John Hogan: And you can imagine, nobody liked that process whatsoever.

Host: No, of course.

John Hogan: That was the worst part of travel. And so we were tasked to try to design a system that could be a good functional, usable toilet. So, we did that, and with something similar to what they had on, when there was Spacelab. And they had a lot of room in there.

But anyway, we had to do some microgravity testing of that. We didn’t use real people. We had systems that simulated various processes. So, I got to do quite a number of parabolic flights, testing that system out. Yeah, so you get 22 seconds of freefall where, you know —

Host: Stage fright.

John Hogan: — and then there’s two minutes of 2G where you’re coming back up. And so we’re doing all of our sort of resetting operations in those two minutes when your arms weigh twice as much and you weigh twice as much. And then you wait for those 22 seconds. So, this happens essentially 50 times per flight, and we went out for many different flights, testing different concepts. So, we got to play around once in a while. I’d recommend anybody out there who gets a chance to do this, you will enjoy it, and please do take the medicine.

Host: Oh, I imagine. I was going to say, even just talking about it. The 12-year-old inside of me has so many poop jokes coming in that I’ve just got to hold it all back.

John Hogan: Well, they did call us poo crew.

Host: Nice.

John Hogan:Yeah, so we really appreciated that.

Host: It’s just one of those things, you would take completely, gravity, for granted.

John Hogan: Right.

Host: It helps a lot when you’re going to the restroom.

John Hogan: Yeah.

Host: It’s not coming back the other way. How long were you — Are you still working on this stuff now? Or how did your career kind of ebb and flow on that?

John Hogan: No, actually now — So, I did a lot of work — From there, I started also working with the air team. So, this is how to capture carbon dioxide and water out of the air. So, if you were to tape up this room and have no air come in and out, we wouldn’t last very long, and carbon dioxide would kill us relatively quickly. And so there’s always a system that pulling out carbon dioxide from the station air, or any spacecraft air.

And so, we’re trying to design systems that [regeneratively] pull it out. Things like the space shuttle used to use a lithium hydroxide canister. It would chemically combine it, and it would get used up. And then you would see the astronauts, pictures of them, changing out the CO2 canisters. They would just bring enough canisters with them to handle the load expected during the mission. It’s not a long mission, so it’s not so bad.

Host: And that’s literally just taking carbon dioxide and turning it into oxygen through a process or something? Or it’s just trapping it and getting rid of it?

John Hogan: No, no. Trapping it and getting rid of it, yeah. It’s just trapping it in the canister.

Host: Okay.

John Hogan: But when you go out for longer periods of time, it’s too much mass. It’s not a good way to do this, so we develop regenerative systems. So, they have a system on ISS right now called CDRA, which is a four-bed molecular [sub] system. It pulls out, first, the water. You know, the CO2 absorbent that we use is very sensitive to water, so they have to pull out the water first or else it absorbs mostly water.

Host: The moisture that’s in the air, is it water out of the molecule?

John Hogan: In the air. It’s out of the air. So, it would be just normal air that’s in this room.

Host: Condensation or whatever.

John Hogan: Yeah, always breathing out water, we’re always sweating a little bit of water, so you need to pull out the water all the time too. Otherwise it would just get completely humid, 100 percent humidity, and condense, and it would be a rainforest inside —

Host: Yeah right, how stuffy it gets.

John Hogan: Yeah, it would be a disaster.

Host: Not a fun time.

John Hogan: Right. We’re very responsive to humidity. So, you pull out the water first, but that’s not what you’re looking to do. You’re just doing that because you’ve got to pull out the CO2. And then the dry air goes to the CO2 beds. There’s one that’s absorbing, and there’s another bed, they call a swing bed, that is desorbing. So, it’s thermally being heated, it’s rejecting the CO2, and we capture that CO2, and it goes to a system they call Sabatier, and that is a carbon dioxide reduction system.

It takes hydrogen from split water. So, we get an oxygen station by splitting water, H2O. We knock the hydrogen off and we get oxygen off of that. And they hydrogen that comes off of there, we combine that with the carbon dioxide, the Sabatier system, and it produces methane and water. We keep the water because that’s where the oxygen is, and we throw the methane away right now. We’re just completely venting the methane.

Host: Okay. But I would imagine the ideal situation would be you use the methane for something.

John Hogan: Exactly. Yeah, right now there’s four hydrogen molecules leaving with every carbon on the methane, and so we’ve become hydrogen limited in this system. So, we’re also looking at methods of how to get that hydrogen back. I’ve done a lot of work there. Most of the work I’m doing right now is in the synthetic biology realm, because I’m actually a microbial ecologist more by training, in terms of environmental science.

We have a lot of projects going right now looking at bio-manufacturing where we are trying to use things like carbon dioxide. In fact, we have a carbon dioxide-based manufacturing project going on right now. This is, you know, I really enjoy this one, so I’ll spend a minute or two on this.

But, you know, if you think about our future here on Earth, right now we make an awful lot of the products that you see in this room, or anywhere, out of fossil fuels.

Host: Yeah, exactly.

John Hogan: All the plastics that we make, any kind of plastic clothing.

Host: All the energy it took to make it those things.

John Hogan: Exactly. And the chemicals which you never see, which are designed to help make things, and make glues and everything, comes from fossil fuel. And at some point in humanity’s future we will not have fossil fuels anymore. Not stored the way they are now. And things we make out of biomass, so trees and corn stover and all the things that plants grow, we won’t be able to replace that manufacturing capability by growing more plants. We already have a food limitation issue.

So, one of the main ways that we’re going to be making things in the future is pulling carbon dioxide and water out of the air anywhere you are, because it’s always flowing past. And nitrogen is flowing past. And so you have carbon, and oxygen, and hydrogen, and nitrogen, is the four atmospheric commons anywhere you are, and renewable energy wherever you are. And we’ll be converting that into the products that we need directly.

We won’t be going through the millions of years to make a fossil fuel, and then use it very quickly, 0r the many years it takes to grow a tree and make a wood piece. We’ll be going directly from —

Host: Go straight to the molecules.

John Hogan: — from atmosphere, to the molecules of manufacture, and making things that way.

Host: And when you’re talking about pulling carbon dioxide out of the air, especially even on a space station, I think the first-place people who, if you’re environmentally focused — I mean, my brain, the first place it goes to is thinking, we’re on a planet that’s creating a lot of CO2. Whether it’s humans, cows, or power plants, we make a lot of CO2. Is there any hope to expand, or start pulling some of that out of the air on a larger scale?

I mean, this is just research for a very small environment but, you know.

John Hogan: Sure. This will be a component of maintaining a reasonable CO2 balance on the Earth. When you look at the actual CO2, carbon balance, and I’m not an expert in this area, but when you look at the general numbers, the amount of carbon that’s in our manufactured goods, durable goods, is small in comparison to the amount that we’re actually liberating through fossil fuels, and/or cutting down rainforests, or changing soil use, or opening up permafrost areas.

But as part of a sustainable ideology, no matter where we go, whatever planet we’re on —

Host:This is very true.

John Hogan: — it’s going to make sense to learn how to do this and do this well. Currently it’s not very economical.

Host: Yeah, obviously.

John Hogan: Right, as compared to fossil fuels, or getting sugar out of sugar cane. Making those molecules is not as cheap in the way that, where we currently are. But that’s, you know, there’s an awful lot of — You can’t fool physics. There will always be a certain energetic responsibility that we have to own up to. But the advancements that can come in the future are something that we’re trying to forward quite strongly, obviously for the use in space, but we would expect all of those to come back and be useful here on Earth at some point.

Host: I always hear, anybody who’s working on the international space station, it’s always, working off the Earth, for the Earth.

John Hogan: Right, exactly.

Host: And the things, you know, you can be incredibly efficient up in space, and applying that to how we live here is critical.

John Hogan: We do a lot of stuff to make it work in space. It’s high reliability, is often really important. So, when you think about an old car, the old Fords when they first came out, not so reliable.

Host: Got the job done, but you had to fix them up.

John Hogan: They’ve increased in complexity dramatically, but even though they’re much more complex, they’re much more reliable. A lot of that kind of technology development is going to happen. The miniaturization of things for space is also really important. Down here we don’t care if things are somewhat big. It’s a transportation issue, or we don’t have much room.

But there, we need a GC mass spec to be the size of, you know, a loaf of bread or smaller, which drives all kinds of different innovations that you normally wouldn’t think about. Then the applications start to blossom of where you can put this, and where to use this.

Host: Yeah, you just never know where the technology is going to go. I’d imagine talking to myself in middle school with a Walkman, a Gameboy, and books, and a telephone or a cell phone. If you were to have told 12-year-old me it’s all going to fit in one little piece of metal and glass, I’d never even fathom that that could happen.

John Hogan: When I was in grad school, I was taking data off of paper sheets and graphing them by hand on graph paper, and taking vellum and hand drawing ink drawings over it. I spent weeks and weeks and weeks and weeks just sitting at a desk doing that. Now that would be seconds in comparison. The calculations on a calculator, right, was dramatic.

So, we keep seeing those sorts of advances. I really look forward to seeing our advancements in, as we become more aware of our roles as life support systems on Earth, that we’re not just guests here, but we’re crew. So the Earth has all of its life support systems, and we will become Earth life support. That’s our eventual reckoning, essentially, as we mature as a species. As we keep going. I really look forward to seeing what happens in that realm.

Host: Yeah, it’s definitely an exciting future. So, for folks listening to the podcast, if you have any questions for John, we are using the hashtag NASASiliconValley, and all the fun social media stuff. If you want to go old school and give us a phone call, we are at (650) 604-1400. Call, leave us a message, we could either bring it back to John, or we can add that and have John come back and answer the question and figure out how to do that.

But thanks for coming on over. This has been fun.

John Hogan: Great, thank you. It’s been great being here.

[END]