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So one more try. OK, at least I'm getting audio on my monitoring and here, so. I'm very sorry, it seems like the obvious finally started dying on us after having run for like one and a half weeks straight. So there's a technical limitation of what we can do. I'm very sorry about that. Let's hope that now everything works fine again. Our technical person in the background, Daksh was fixing stocks now has full control again and will hopefully switch back to Earth. So and you can just start again again. Very sorry. OK. No worries. OK. Hello, everybody. And now we had a little bit of a chance to see my beautiful, but now the old who is working, so I shall start and this talk, I'll give you an overview of spacecraft life support systems, maybe a more in-depth overview than you ever cared about, but that is how I roll. So here we go. I'm worse, I'm sitting in Finland right now, as you can see behind me, I'm sitting in a wooden hut next to a lake where the lake is frozen over, and I've been sitting here since March to keep my distance from people because it's the farthest I could be from people without actually going to space. And the whole time I'm giving is basically a Part three in this year. The first one I gave in 2013 at the Glass program here in Germany. How to fly spacecraft, which was basically orbital navigation. Then there was the second possible Typekit spacecraft in 2016, also in Germany, which talked about materials and how to get it all to space and how to keep it together. And now this is part of how to survive in spacecraft, concentrating on life support systems in my normal everyday job. I mean, space physicist I do big plasma physics simulations of the new space, magnetic field, solar, wind and so on. But that's not what I'm going to talk about you. All right. So where are we at? We are in a spacecraft. We are outside the atmosphere, which means there's no air, no pressure. There are cosmic rays hitting us. There are temperature fluctuations. Micrometeor
oid is running around and all these kind of things. For most of these, especially the cosmic rays and micrometeoroid, you can go back to the talk about how to build spacecraft because you basically just need something shooting to get around. But this will especially focus on the fact that we are outside the atmosphere and you need to somehow bring your own air that you can breathe. So what does the life support system actually do? I mean, it gives you a life, but what does a human need to be like on average? And this is from a massive statistics page. One human on a space station consumes 830 grams of oxygen, but doesn't actually seem like much because it's not very heavy. This corresponds to about 12 liters of oxygen or the economic pressure. But of course, you are breathing in much more air. The air that you breathe only contains a small amount of oxygen, and when you're breathing it out, a little bit reduced. So about you only once you mate the 30 grams of oxygen per day, you also eat food. And the average estimate is about 620 grams of food per day. This is very strongly from person to person. And you drink water, and these three point five kilograms are not just water that you drink. So few people drink three and a half liters of water. This is also air moisture, the jobs or to your lungs. This is the overall water balance that you put into your body, and your body does all kinds of funny things with it, and it produces output about one kilogram of CO2. You notice already. You breathe in 800 grams of oxygen and you get out one kilogram of CO2, so this carbon atom is like a transfer from the food, so your metabolism into the CO2, then you lose about 100 10 grams of what knots equals metabolic solids. So that's the stuff you drop in the bowl and then you produce. Flewitt is an output, and that's Europe, and you can see all here that the Moss has increased a little bit because some part of your food with salt, for example, goes into urine and then some other produ
cts, metabolic products that people. So the job of your life support system is to supply the stuff on the left and get rid of the stuff on the right. In a way that does not make you uncomfortable. It also needs to keep the temperature in the comfortable range and keeps notes away, especially ones that are involved with it. Bottom two things on the right. Now, let's talk with air, we want to have reasonable air. And on Earth, we hear around us what one bar of it is refreshing and that is consisting of different things, and now I'm talking specifically about partial pressures here. So when we have this one bar of ambient pressure around us, 78 percent of that is nitrogen. I'm talking just 0.78 bar nitrogen, 21 percent oxygen, one percent others, especially that's helium, CO2, argon, these smaller constituents of the atmosphere. You can also just as easily leave out the nitrogen and run in in in an atmosphere that's entirely on the oxygen. But then you need to have a much lower pressure because otherwise you get oxygen toxicity. The other way round. You can also reduce the oxygen amount in the air, but then it gets quickly problematic as soon as you go under about zero point one five bar of oxygen, partial pressure, you get headaches, it's loss of concentration. And then if it goes even further down, starting at around 0.1 to a bar, you get unconsciousness and death. So you don't want these factors this this. Boundaries here are quite specific from person to person and especially people that live high in the mountains, in the Andes or the Himalayas. They have a much higher tolerance for low oxygen demand because they produce more red blood cells and so on. Then this is something I heard in the talk a while back. The first symptom of hypoxia is consciousness, and that is a problem. If the oxygen amount goes down slowly, you get headaches and you'll notice that you only see black and white. But if your oxygen content rises quickly or slowly falls down quickly, you will n
ot notice your missing oxygen until you pass out. And then it's too late to act. So it's really important that the system keeps this on a good level. This already sets breathing without nitrogen isn't a problem. You can just reduce pressure and only have 0.1 oxygen, which is, for example, what you do in spacesuits. If you do that in the spacesuit, they're much less baloney and much easier to move in, so you have lower pressure. But the disadvantage of this is that you then have a pure oxygen atmosphere and you will have lots and lots of increased fire risk stuff that you would normally not expect to ignite ignites suddenly in the pure oxygen atmosphere, for example, aluminum or. Plastic or any kind of thing that can burn will burn. The Americans learned this quite uncomfortably in Apollo one, which had a disastrous fire accident on the launch pad before takeoff. Well, three estimates died. So because of this, you try to avoid oxygen out in space as much as possible and try to work in, well, imitating what you have both at sea level. Now, how do you do this? How do you supply air that you can be? The obvious and easiest way to do this is to just take air and compress it in a bottle and breathe directly from the bottle via a pressure regulator. So you get air to breathe that and then you breathe it out. And since you're in a spacecraft, you can just be the in space and gas it off. And that works quite OK. This is like the diving apparatus, the disadvantages in this bottle, you have 78 percent nitrogen, so that does actually nothing to your breathing. You're just wasting mosquito and in space like you always want to have stuff as light as possible not to waste moths. So it would be much nicer to somehow recycle the air that you breathe out because you're breathing in 21 percent oxygen and you're still breathing out about 14 percent. So why not reduce that oxygen? But you've just based on? So this system is impractical for more than a few hours of spaceflight and actual
ly no spacefaring nation has ever used the system like this already the first Mercury flight of the Vostok system in honor of the Russians, also the Chinese capsules, all of them are already using more advanced systems. As far as I know, some of the commercial space space planes are now employing simply this method. If they're just doing it properly, fly for a couple of minutes. Fine. But you should go beyond that right away. Better oxygen sources you can use, for example, 100 percent compressed oxygen, you just use an oxygen bottle and breathe on that. Right now, watch out, though, if you're not careful with this, then you have an explosive. This is a picture of a life support backpack from an American extravehicular mobility unit in the beginning of the shuttle program, where this was just being developed and tested. And you can see the oxygen bottle on the site was feeding oxygen into the pressure regulator here at the bottom, and that was made out of aluminum and it caught fire and the entire thing exploded. Two people got hurt. Nobody. Fortunately, died, but that means that even Nazar who are building these professionally have to sometimes find out that they are not careful the same design, despite the waste that they just replaced as one regulator. And ever since then, the same life support pack has been used in the shuttles and the International Space Station ever since. Now there's an even better oxygen source, and that is. Called a oxygen candle. In this, depending on who designs this, either if it's a Russian design, yes, sodium chlorate or for the US systems, you have lithium chloride packed with iron powder. And if you ignite, that's if you heat it up at one ignition point high enough, they start to burn. This sodium chloride just decays to basically, that's a redox reaction to normal table salt rust powder. And then there's two oxygen atoms left, and so that goes out of the system and supplies oxygen. So this is a compact, solid device that you can swit
ch on by igniting it at one end, and then it slowly burns to over multiple hours. So this design, for example, burns for eight hours and supplies oxygen for three people for eight hours, which is very nice because then you don't need to care about pressure regulation and so on. Just ignited on one end, and it's replaced with oxygen. This is actually typically used in space stations as the backup system. Here's a picture from the old Mir space station, where one of these oxygen candidates was just being taken into use next to the regular life support system. This very much up here is also the point where the fire broke out on the space station Mir at the middle of the 90s, which eventually caused the space station to be decommissioned. Because this thing gets very hot on the left, you see the labeling on one of the American oxygen candles hot surface activated. They get up to 500 degrees or so. So you need to be careful with that, but it's a very nice way to produce oxygen without needing any further equipment. These are typically used as the backup system for the more complicated ones that we're getting to next. Now, before we go through the more complicated ones, however, we have to talk about the second half. You remember the initial looks like you have oxygen coming in and then the humans breathe CO2 out. So what do we do with the CO2 just bringing oxygen doesn't make it for life support system it. If you have too much CO2, if you, for example, don't care about removing it collects in the spacecraft and did partial pressure of CO2 will rise in price and you will get lots of problems starting from 10 millibars partial pressure and that's much lower than the O2 pressures you have before you start to tire. You have concentration problems, you get tingly fingers and so on, and then starting from about 70 millibars again, you have loss of consciousness and death, so you want to do something about it before it gets so far. And what can you do against CO2? The straightf
orward method is chemically binding. It's the so-called CO two scrubber approach. You take CO2 and put it into water and it forms carbonic acid. You all know this from fizzy drinks. That's just CO2 will dissolve water carbonic acid. If this is an asset you can neutralize, so you just let your CO2 flow through a container that contains some sort of basic material. For example, lithium hydroxide, you can also use potassium hydroxide. But lithium is a very favorite element in space flight because it's so light. So your CO2 reacts with the lithium hydroxide and it produces water and it produces lithium carbonate, and then the CO2 is gone from your system. These canisters look, for example, like this. This is one from the Apollo command module where you have one site where the eye gets pushed in by a fan flows to the to the surface in there with this lithium hydroxide, and then it comes out purged of CO2. These canisters, indestructible shapes are working to remove the Earth that one person, except for a couple hours. So this one, for example, had to be replaced every 12 hours in the Apollo flights that lasted three days. They had just had enough of the balloon. But again, this is not yet a renewable system. And in the Apollo flights, there was an additional problem. In the flag of Apollo 13, there was an explosion on the way to the Moon. This was actually an oxygen tank that exploded, but not one of oxygen for the life support system, but one that was supposed to fuel the fuel cells for the electrical system. So the electrical system was gone and they couldn't use the command module anymore, and the astronauts would all have died. If not, they had the lunar lander attached to the spacecraft. So they evacuated to the lunar lander and were just living in there while they were flying around the moon and back to Earth. The problem with that is that the lunar lander was designed to support two people for two days. And now it had three people for three days. So it's lithium h
ydroxide canisters simply were full before before plant and there was no backup. They brought the canisters from the main command module and found that actually, since this is a US government spacecraft, the command module and the lunar lander were built by separate contractors, and these contractors were not talking to each other. So they used very different design of their canisters, and these did not fit together. So the thing on the right was what they would have needed to put into the lunar lander life support system. But those were full, so they only had the ones on the left. And then they had to get creative, and which for me is the best proof that you can fix everything with gaffer tape if you only have enough of it. So they built an adapter out of some space spacesuit horses and a small ventilator, a book to cover lots of gaffer tape around the lithium hydroxide canister. And then they plucked it into the life support system in the back. You still see this is where the original canisters were supposed to go in, and then these were patched in. It also contains a dirty sock in the middle, they have to stop this little hole somewhere. I wanted to throw something. So yes, with enough gaffer tape, you can fix everything, even in space. And then we get to space, huge life support systems, they're basically the same idea, except built in a compact way. This is the backpack from an Apollo moonwalking suit and you see here all the components we had before. There's an oxygen bottle that supplies breathing air. There's a CO2 scrubber that's sitting here horizontally. And then this power supply in some pumps and at the top here is a evaporation device to cool the space you and you're in direct sunlight on the Moon. That's basically all there is to it. The more modern designs look kind of similar, this is a Russian Orlan spacesuit that is nowadays being used as this. You flip open the back of it and you climb in behind and then you open the door of your cosmonaut collea
gue, opens your closed the door behind you and seals at you. And here you can see as well there's an oxygen bottle, there's a scrubber container and so on that supplies oxygen for eight, since it's only only about 800. You can carry it all around in your spacesuit. And since you are in weightlessness anyway, weight doesn't matter. Now, if you want something like this, if you know, thinking, whoa, I want my own spacesuit, I don't want to breathe the air of the people around me, which is very understandable in 2020. You can actually buy these, for example, scuba breathing systems are commercially available. They set you back about 7000 euros, but you can just go to a diving store and buy one of these. And these work very much by the same principle. You have a oxygen bottle attached to the back and you have a container with soda, lime and soda. Lime is nothing else but potassium hydroxide. Mixed with some of the stuff, some days to see when the Dakota has saturated it and so on, but that's exactly what it is for. And I know some people from the diving club of Aalto University shout out to them for from here that own these devices and they have actually been going to the supermarket with a breathing glue to shop for groceries during the crisis. So if you don't, for whatever reason, want to breathe the same air as the people around, you get a scuba repeating device. It might also be useful if later you get to own a spaceship or something. Right now, now that we know how it works in the basic form and in a space suit, let's look at some actual life support systems that are being used nowadays. The SpaceX Dragon two, which is currently attached to the International Space Station, has a pretty much run of the mill life support system that we can now understand. Here's a diagram from the from the basics publication about that. You can see the capsule, the pressure vessel and basically at the bottom or under the floor covers is where all the magic happens. There you have a bu
nch of things that we can now identify here. On both sides of it are these bottle. They have two times three bottles of these, actually only one. The top bottle each is filled with pure oxygen and the bottom two are filled with a mixture of nitrogen and oxygen. The idea with that is if the capsule were to be evacuated, either because somebody needs to climb out or this leak that can be pressurized with basic compressed air from these two bottom bottles. And then to refresh the air as astronauts are breathing, they only need one of these bottles each. Also, during reentry, in order to cool the system, they just about cooling their open the valves and blow air through it, which causes the capsule so they don't have any need for a more complicated cooling mechanism. In addition to that, they have these sort of lithium hydroxide canisters that actually a commercial model that apparently you can buy it for submarine operations. And these are a bit larger than the ones we've seen before from the Apollo thing. So this actually can be left in place for one day or four person crew and spacecraft. And you can take them out and exchange them. They have this replacement rack to the site you. If you're in the spacecraft and you look down and you open the covers, it looks something like this. You see the bottles here on site and then you see the active lithium hydroxide canister for CO2 scrubbing there and then the three replacement ones. Once a day, one of the crew members open it and swap the kind of stuff. But then you also have the urine container and the waste container, so maybe you don't want to put your hand in there in space. One funny feature of this life support system is also the toilet, which is part of this sits on the ceiling. So when you launch you, you're actually sitting under the toilet of the spacecraft. Of course, during launch, it's probably unused it. I'm not sure how trustworthy this seems to the astronauts on reentry window then suddenly sitting under the
toilet. But apparently this works well. I've heard no complaints about it. All right. So another real life life support system is the so use cockpit, and you may have seen something like this in the movie gravity or something like that. It's full of displays and buttons and levers and so on. But the user interface of the life support system is actually completely supplied by these three valves. After two middle ones, which can be used to regulate the oxygen flow from the main and backup systems. And then for the last stage of reentry and also for emergency cases, the valve left open see emergency oxygen flow, and that's all there is. The fans are always running the CO2 scrubbers, all the scrubbing, and you do not need more than this as a user interface for your life support system. So you don't need to worry that much when you're in the Soyuz craft. If after a night of drinking with some Russians, you suddenly find yourself waking up in a Soyuz craft. You don't need to mess with many controls. If you have too little oxygen, you just turn this off. That's. So now we've been talking about all these practical things that have been used in spacecraft, but these are not really reusable. I mean, we have oxygen bottles when they're empty, they're empty. We can't get new oxygen in space and we have CO2 scrubbers. And when they're saturated with CO2, then therefore then you need to go back to Earth. So both the Soyuz spacecraft and the Dragon two have very reasonable life support systems for what they're built for the flight to the ISIS, and then they come back in 90 minutes if you want. They don't need anything more fancy. But for the space station itself or anything more complex than that, you want something reusable and how do you do that? There is a very practical, endless source of oxygen available if you have electrical power because you can simply take water, H2O and with electricity, split it into hydrogen and oxygen. On Earth, it's quite easier just to electrodes,
water at life, electric current. You see the. One side if you hydrogen or the other one side gives the oxygen. It's not that easy in space because the if you put an electrode into water in zero gravity, it forms the bubble around the electrode. And then the electrode no longer touches the water because the bubble doesn't go with. But you can do it, and I can show you in a second how you do it. First thing, though, you need to have a good source of water that you are not planning to use for anything else, like drinking. So what's a good source of water that you do not want to drink anymore on the ice? They simply use the toilet. Astronaut P gets recycled into the oxygen system on the ISS. The oxygen system looks like this, so sometimes people ask if you are on the International Space Station and you're staying there for six months, do you have to drink your own pee in space or something like that? And the answer can be a resounding no. You don't need to drink your own pee. You will breathe your own penis. So. How does this work, then you see these two wrecks are the life support water recycling system of the SS. We have here a centrifuge where the water gets boiled and separated from salt and any other more complicated components of it. And then we have two more centrifuges that are the electricity system that actually takes the hydrogen and the oxygen apart. There are also other things like. Filter system to get any other pollutants out and then you need to regulate the level and so on. But in the end, pee goes in one side of this device. Oxygen comes off the other. And since you have solar panels and much more effective solar power and space on Earth, you can produce basically endless amounts of oxygen by just splitting up. Which leaves you with the problem of CO2. How do you do a reusable CO2 scrubbing? And here nature gives us some wonderful materials, for example, activated charcoal. If you have a surface of activated charcoal, actually let air continue to run o
ver it. CO2 molecules like to attach to the surface. But only one molecular layer. There are others that are working even better than charcoal, for example, there are some zeolites and some amines that useful that not going into too much detail at you. So you let it run over and it touches on the CO2 molecule stick to the surface. And after about one hour, the shockable filter is full. No more CO2 attaches to it. What you can then do is you close the valve to your spacecraft and open the valve on the other side and open this surface to the vacuum of space and you heat it up a little and evaporates off to space. And then you've got a clean piece of charcoal again. That's exactly what this device does on the International Space Station. This is the so-called carbon dioxide removal assembly, and it has these fancy violet connectors. I like the design of this very much. It has some zeolite absorption bits by the cabin egg it's run into. And then after an hour or so when it's full, it gets closed off and open to the vacuum of space. And because then it's half the time up and half the time closed, there are actually two systems that are alternating between open and closed state. Here at the bottom, you see these two openings where it then attaches out to the other side of the spacecraft, and that leads off to the vacuum of space. This method is called pressure swing adsorption because you are swinging between inner pressure and pressure outside. Now, if you have your CO2 removed, you can just vent it out, and that's mostly what is being done in International Space Station, but there is another helpful chemical reaction that makes even more sense to do after. We have CO2 and we're just separated it using our precious wing mechanism. And we also didn't have the hydrogen left from splitting our water. I mean, we split the water and we're breathing the oxygen. What do we do with the hydrogen? If these two are put together, they can chemically react to methane and water. Isn't
that nice because we have something that we don't want and something that is no use for us and we get something at least part of it. All that is food again, water as an input in order to do this. Unfortunately, it requires pretty high temperatures, so you need to heat these up to 300 tubes and you need to do it under high pressure so that the molecules actually react with another. You also need two catalysts. Nickel is quite normal for this. Ruthenium is more efficient, but much more expensive. So that's what's used in space because money doesn't matter. And then you need to first compress it to that and expand it again for use in the space station. But the advantage of this is from the original water that you put into the splitting. You have four water molecules that went in. You still recover two of them back. So you are getting half of your water recovered in these cycles. This is what the device looks like on the International Space Station, and it has lots and lots of troops and complicated mechanisms. Because it contains decompression stage, it needs to mix the input gases, needs to separate the output gases and then expanded to. So it's installed right next to the carbon dioxide removal assembly. The second output have methane at the moment is just dumped overboard from the International Space Station, but in principle, this one can also still be used for something useful. It can be used as a rocket fuel space. This new rockets run with this, or it can be heated and electrically decayed to decompose to carbon and hydrogen again. Then you have the hydrogen used reusable. The problem with this is that you need to basically put this in a steel tube and heated 2000 degrees, and then you have the carbon starting to lay on your steel. So this is not something you want in the space station right now, and this is not something that's overly, overly practical, but it's a possibility for the future, maybe on a Mars. You can do this to get carbon for also for of virtua
lization of sorts. So let's plug it all together. This is life support system looks like this. This is the American life support system in its original design when the ISIS was launched in 1998. You still see here is a fancy tube screen that was used for computer controlling it and so on. This is also still the design that was supposed to include a shower kit in the shower never actually made it to the space station due to weight restrictions. But this the toilet. Then there's the water processing assembly, the O'Toole generation, the carbon dioxide removal and all that. So it's not small, but it's also not too big, given that it's mostly regenerative as a diagram. It looks like this. It has all the parts we never talked about. It generates oxygen by splitting water, it removes CO2 from the air, and then part of the CO2 is still vented overboard and part is fed Sabatier system. Also, part of the hydrogen is vented overboard and part is fed into the system and then the methane gets into global. Noteworthy here is there are only two inputs. This one is nitrogen, which is just used to regulate the atmospheric pressure. That's actually a very small amount. Basically, you only need to contract some leaks in your station. Not much. And the other one is only water. So the only thing you need in the ice is to keep people alive is water and electricity. How much water? I found some conflicting reports. I look to is a status report of the last couple of years. One thing I found from 2010 was talking about the entire station using a seven and a half liters of water per day, which is not that much. But then, with newly updated systems, a more recent report was talking about only a little bit of a one liter of water per day. And that would be quite amazing because that's a tiny amount to supply all the tremendous. Yet there's still a venting of bullet, and especially it's it's kind of unsatisfying that this carbon atom. I mean, it came into the human body as food and we breathe
that out CO2 and then be vented overboard. Wouldn't it be nice if there was somebody who would like to make use of the carbon? Wouldn't it be great if something produced the carbon from CO2? And indeed, there is. I mean, we humans turn oxygen to CO2 through respiration and the other way around plants and other marine life forms, for example, cyanobacteria and some other micro-organisms. So in CO2, back into oxygen through photosynthesis. And experiments have shown that many plants do just fine in space without gravity. There's a picture of salad growing on the SS as they grow these on. Not actually in soil, but in some growth pillows that contain nutrients. And then you put the seed in and a little bit of water and the gold in general, plants that want to grow upwards and want to form stalks or grow away from gravity have a bit of problems in zero gravity because they don't know where to grow. And then they get weird shapes and sometimes don't properly work. But if you have something like this, which is just a cell, it just wants to be a leaf. It grows just fine. So the question is, why not just stuff your space plant roof full of plants and see if that works as a life support system? This is not just a good idea to support you to get your CO2 away and supply you with oxygen. It's also such that plants are psychologically been shown to be a big comfort factor. I mean, if you are living in a gray box office spacecraft all the time, it's actually very nice to be able to tend to a little flower now and then maybe even talk to it if you're starting to go crazy. Well, before you started to go crazy, this picture here shows the first flower that has ever bloomed outside the Earth. That's Xenia. That was the video zero one experiment on the Earth. You see the same plant pillows being used. So this begs the question how much green stuff does one human actually require for its life support and. Basically, all spacefaring nations have done some experiments about that, the Rus
sians were the first ones they set this up. The Bio's facilities by history, especially since 1972. This is an underground steel and closed. Well, the laboratory in the wonderful city of Krasnoyarsk in Siberia, where people have been living since 1972 in continuous experiments, they have successfully had people in complete isolation. So the system was shut off only electricity, electric power going in for 180 days and they were eating the food that they were growing and the plants were supplying their oxygen worked fine. Their research showed that you need about eight square meters of plant growth area to supply sufficient oxygen for one person, which is not as big as you might think. Of course, they chose plants to be ideal yields, especially there are small growing varieties of wheat, super wheat and dwarf wheat that grow very quickly and produce lots of biomass. So eight square meters, they found, is sufficient to supply oxygen for one person. They also found that it's not sufficient to supply food for one person, and their calculations came two that you need about 11 square meters to supply food for one person. Yet they supplemented protein and some additional meat products and so on from from their stores. So they did not just only eat the stuff they grew their. The Chinese space agency and China is very keen on going to the Moon. They also have a very similar experiment running since 2014. The Moon Palace, one in Beijing looks like this. It has two growing chambers and one living chamber, and three people have successfully lived in there in isolation. For the longest I found was one hundred and five days, and the difference to the Russian system is it's a more modern form of of enclosed farming. They are using vertical farms stacked in multiple layers with LED lighting, so it's more energy efficient. And then they are also recycling the human waste as fertilizer, and they are growing their own animal protein by having mealworms. And there was a very funny part
of the the article that they had invited Western astronauts to participate in the study, but they refused due to the idea of eating mealworms as their primary diet. But apparently mealworms. They get about finger sized and they are 75 percent protein and quite practical on close ecosystems like. Then the Americans always keen to overdo things, also had a experiment for enclosed ecosystems called the Biosphere two. In the end of the 80s, a billionaire decided that he wants to do the biggest and best ever biosphere project like this and invested enormous amounts of money building this in the desert without consulting scientists. Too much, though. And it turned out not so well. The first experiment was unsuccessful because, as it turned out, if you put a greenhouse full of plants, you have trees. Here you'll see wood, which is not me or just brown, who does not photosynthesis. So a lot of the biomass they put in was actually not doing anything. They also had two parts simulating desert. And as it turns out, the cactus is not a good source for photosynthesis. If you want to live off it, then they also wanted to make it look like nature. So they built all these stone structures out of concrete, and they used the same kind of concrete that, for example, Disneyland uses to build artificial mountains and so on. The problem is when concrete is freshly set and curing it is absorbing CO2 from the air because of the reactions that are going on in the computer room. So what happened there is that the concrete absorbed all the CO2 from the air, which was fine at first. But then the oxygen, like the plant stopped doing photosynthesis because there was no CO2 for them to work with. And then the oxygen gets dropped and they had to resupply multiple times oxygen from the outside because it did not really work. There are nowadays other and less overdone closed ecosystem research facilities. One in Utah, one at the Johnson space is Houston, and they are on smaller scales, producing ve
ry successfully enclosed by a life support system. Results. But this one was a quite famous and quite unsuccessful one. In spacecraft so far, there has not been the attempt to supply large amounts, the major amount of life support to plants there are, though, some experiments on the Earth, apart from the plants that we've seen earlier that have mostly grown to test plant growing, per say, there's now a so-called photo bioreactor running the ices. This is the wreck of the European life support system that works in a similar system as the one described before. And on its CO2 output lines enriched to CO2 enriched air gets fit into these boxes here on the site. And in these boxes, there are other microscopic chloride bodies in the water solution, and they are being supplied to the CO2 rich air and light, and they turn it into oxygen and they also produce edible biomass. This very same alga is used, for example, in Japanese cuisine as a seasoning, so you can use it or you can drink it as a protein. Shake me inside these boxes. This reactor looks like this. You have a bit of a problem if you want to bubble CO2 to a solution in zero gravity because bubbles don't rise. So this system is pumping the air and water mixed around through this lighting source all the time. And that way, the water by erector produces oxygen, so that works well. Here's another picture of another astronaut just taking out the bottle where the other solution is stored so you can. After a while when the I have grown big enough to take this out, you put some of it or maybe drink it, maybe bring it home to Earth for analysis and fill in your water and some nutrients and put it back in to continue operations. But as soon as you saw this is just a small device, this is maybe 10 centimeters by 10 centimeters. This is not enough to supply even a single human. We've seen you need maybe eight square meters of front. It's a it's a test, but since it seems to be running well, that's something that can probably
be scaled up to run the entire spacecraft life support systems. The second one that's been on the. ISIS, that's also very interesting. This is an even smaller one, so this is we can see the comparison to the fingers has been using cyanobacteria. And if you go to the supermarket and buy spirulina tablets, it was all like dietary additions, green bean tablets that contain protein. This is exactly the same cyanobacteria that they use in that. And this also manages to produce oxygen quite successfully. And I'm thinking this specifically because this website about a guy who just did this at home, he took some, some clear bottles, put these cyanobacteria and water in there and produces on oxygen that way. So if you have a hackerspace and want to run it like a spaceship, you can think of just doing that. You take some maybe clear glass or plastic tubes, fill them with water, put these cyanobacteria in and you produce your own oxygen and get rid of CO2. So again, another hint for the year 2020. If you don't want to breathe other people's air, this is a very practical way to do it, and this can be basically done with hotspot material. Then. One thing to think of if you have an enclosed ecosystem, even if you have perfect CO2 removal and oxygen replenishment, you are still in a closed box and you're still breathing the same air over and over again. Whatever other gases you produce, and I'm not specifically talking about gases coming from your butts, but I'm also talking about those even small concentrations will accumulate over time. So if you are not taking care of them, your spacecraft will get smelly and might also get in other ways, problematic. One example was a plant growth experiment on the Russian space station Mir. They were trying to grow wheat just to see how well it goes in zero gravity. It was a continuation of this Russian Bio's experiment, trying to run it in the middle and everything drew well. They even got large amounts of results. This is from the research
paper. They found that everything grew even better than on Earth. And when they returned the seeds to Earth, they found that all of them were sterile. And I didn't quite understand why. I mean, there was no obvious DNA damage from radiation or anything, and there was also no obvious reason why Zero-Gravity would make me see it sterile. And then they did a bunch of experiments, and after many years, they published this paper and found that actually ethylene gas was trapped in the space station and that didn't do anything to remove it. And ethylene gas is a plant hormone. You probably know it's from the supermarket bananas. If you have a supermarket, you can always buy fresh yellow bananas. But they're being harvested on the other side of the planet. So how does that work? You ship them while they're green and then you give them ethylene gas. And that's a hormone for the bananas to turn yellow and ripe and has lots of different effects on different plants. And as it happens in the concentration that they had here, it made the weeds grow. Sterile, so this doesn't work. So you have to take into account what are used to trace gas concentrations as you grow plants in space. And this actually also leads to the interesting question if plant hormones, gases, plant hormones have some strong effects in wheat. How is it with humans? I mean, so far, we've always had astronauts under very controlled conditions in space stations for a long time. But what is in control in commercial space flight coming up? You will suddenly have, let's say, teenagers flying in a spacecraft to do their hormones suddenly accumulate. Does it cause psychological problems? This is nothing that's been researched yet, but I find the idea very interesting that maybe there are biological messengers that we actually are unaware of that are very much concentrated then causing some issues in the future. Another thing that is a problem in space stations is smells, not just smells produced by humans, but also mo
lds. Here's a picture from the International Space Station. It's on the in the Russian, I think the space, the module where the astronauts typically hang their towels to dry off the workout. And as you can see, there's a nasty looking black patch of mold growing there. I'm not quite sure which mode this one is, but there have been samples from different parts of the ISS brought to Earth and analyzed, and I found that Aspergillus nigar, for example, that's the common black food. The girl was very nicely on the ISS and there were ideas. Maybe this needs to be sterilized. Maybe we just go around with a big UV light lamp because UV light tends to kill fungal spores. But as it turns out, Aspergillus kneecapped produces melanin, which is just the same brown color, and that's also in skin and hair and so on. And it produces so much of it that it's basically resistant to UV radiation, so we can't kill it like that. You also can't kill it by shutting all of the doors and evacuating the air, because as it turns out, it has spores that survive vacuum. So it looks like you will not get rid of mold in the spacecraft anytime soon. At the moment, they're just scrubbing the surfaces with alcohol now and then. And that way, trying to keep it in check on the space station Mir. There was in the end of its lifetime the problem that actually mold was growing through insulation foam layers on the walls of the space station. And the smell got so bad that astronaut cosmonauts apparently developed a so-called second space sickness. The first one, their normal space sickness you get when you fly to space and you get weightlessness and some people throw up. And then there was the second from one of our astronauts returned into the space station from, for example, a spacewalk where they had seen spacesuit. And then they went to the space station and it smelled so bad that they got physically sick from it. Likewise, there are stories of Soyuz spacecraft landing in Kazakhstan and the people that
open these space capsules for the first time, they have problems that the astronauts brought with them the ugly smell of space. So spacecraft tend to be quite smelly. It's it's how do you get rid of that? Well, one way, of course, is plants help with this. If you have lots of plants, they make you ask me a and they they feel that they are especially the sort of plants that have air roots. They just make the room atmosphere better. This is, in this case, literally the way they do it. But you can, of course, also use chemical methods for if you heat your air to 500 degrees, it destroys most organic molecules. They just simply do produce and fall apart or burn with suitable catalysts. You can also make this more efficient. You can also make it destroy ammonia because ammonia is a compound that forms in your sweat. And if ammonia accumulates too much, it starts to attack plastic and parts of the life support system, so you want to get rid of ammonia and sulfur and so on. So lead still, keep your air up, run it over a catalyst and just keep cycling through it. And that keeps the trace contaminants on the ISIS control. Activated charcoal filters also work well to get more more complex molecules out of the air. All of these are running the analysis. The problem with this is that they are still quite bulky. If you have a small spacecraft, you just want in a small capsule to return to Earth, you normally don't have these and these tend to get smelly. So if you are thinking in terms of science fiction and and nice and fancy stuff that we might be aware, most of this spacecraft you see in such a cheap, probably very smart. Right, and that brings us to the conclusion. Life support systems have developed lots and they are practically surviving in space, and they are not too bulky, but also not too small. It's almost time for completely closed systems. We're still venting a bit of the International Space Station into space all the time, but with enough plants in the roof, it's p
robably going to be seen such that you are in a completely enclosed, distant way when you need to put electricity by a regenerative systems are not just important in space, you can also help them at home and live nicely with them. So if you run your hackerspace like a spaceship, maybe start building one yourself. It's not that complicated. If you want to learn more, I've published a book about all this and even more. There's also a German version if you Google for it, it's available in the typical places where you find books. So I am very much looking forward to the questions and hope you learned something for your life in space. Yeah. Blown pretty amazing talk. One thing, maybe that we want to fix right away, we're still having some audio issues and I'm very sorry about that to the stream we luckily did. Back up, recording locally at all this place, like, like we said earlier, he's like in the depths of Finland, somewhere in the little hut and in connection is not that great. What's amazing is working as a this was, if you could, in there in the share that we have this webcam share a small icon on the bottom. If you click on, that will turn off your video. And we are hoping that even though we cannot see it anymore, that maybe the audio now has a better bent with a friend. At least, yeah, we can hear you better. Yeah, let's try it like this, see if this works. OK, so our lovely signal angel has collected a bunch of questions and the chat was super on fire. Like I actually had the IFC channel open all the time and I saw messages, scrolling feeds, so shout out to each other. Yeah, I think this was like the worst shift ever for a signal angel. So much to do, but there are a few questions. So let's go through them. First question was Wait, can you brief just 100 percent oxygen at 0.2 bar? Yes, that works, this is how it's usually done in space suits in order to reduce their bulkiness, you just reduce the pressure. The problem is not breathing 100 percent oxygen, that 0
.2 power. The problem is getting there because if you start from a normal environment like sea level environment, you just. Depressurize, you still have your blood were born because you have lots of gases dissolved in your tissue, in your blood insulin, you need to really slowly go down with your pressure. Otherwise you are. Your nitrogen is going to form bubbles in your in your tissue and tear your body apart. So what they typically do on the International Space Station is they go to the airlock a couple of hours before a spacewalk and start to lower the price. I'd read you in the past, what they used to do was camp out. So overnight they were already the night before sleeping in the airlock and then the next morning they went out. Nowadays, they found a more efficient method as they put on this spacesuit with normal pressure, start filling it with oxygen slowly and reducing the pressure, and then sit on the cycle ergometer and to cycle cycle cycles because that pumps the air or the nitrogen out of your system. So it's a similar problem. If you are diving and you are 50 meters depth and you suddenly come to the surface, you would die because of the compressed nitrogen expanse. And that causes problems. But apart from that, yes, you can easily survive in 100 per cent oxygen atmosphere as long as the pressure is low enough that it doesn't get toxic. Yeah, it's like when diving, you know, normal atmosphere is sort of space and diving as your spaceship and you need to slowly depressurize. Next question regarding oxygen candles if this thing burns through at least oxygen, doesn't that need oxygen for the burning process? Again, I think there's maybe a slight misnomer here, and not really. I mean, I can probably go back to the slides wherever it was. They don't need oxygen for burning because it's a redox reaction. I mean, you have the potassium chloride sort of chloride coming in, and I reported that reacts with and it simply passes one oxygen from this one to the ihren
. So the oxygen ends up here red objects and just reduces and oxidized at the same point. So it brings its own oxygen along and it actually has oxygen to spare. That's why these produce oxygen stable. Mm-Hmm. Interesting. Yeah, something for the chemistry nerds there. So these slides will, of course, be up in the recording and you can go through the equations, probably and found that out herself. Is there any advantage to using either sodium chloride or lithium chloride? The advantage of sodium chloride is that it's just dirt cheap. It's really just table salt that you can get from anywhere and then you just need to have the reactions to get the oxygen on there. In compressed lithium flow rate is more of a problem. It's more expensive, and B lithium salts in general have psychological effects if they get out. If you have any dust coming out, defense holes have been used for a long time to try to cure depression. So you don't want too much of that flying around in the space station. The advantage of lithium, on the other hand, is that it's much lighter and weight is almost a premium in space. So it's a trade off and the Russians have decided to go with sodium, whereas the Americans have decided to go with lithium. So that's both. Cool. And that's the question, I think, to the equation where, you know, inputs of some Nessus and output of some muscles. And the question was so the additional carbon that's essentially coming from the food sources. Could this be recycled and plant materials? Yes, I mean, that's basically what the second half of my talk was about. I mean, I saw the Christian scrolling by as I was still talking about their methods in the beginning. That's exactly the point you have to carbon coming from the food, going through your system, being trained to do so too. And then the plants do the opposite and turn it back into their sugar so that they continue to head south. So that's where the idea comes from to use plants as life support systems. Yeah, prett
y much like a circle of life inside a spaceship, essentially. Yeah, I was I was thinking in the beginning, should I draw this such that these errors actually go around? But then I thought, it's a bit disgusting to just throw an arrow from the brain back to the what? Well, it seems to me like there's lots of pretty disgusting smells and everything, so people might not have been shocked that that much. When I was actually talking to a Swedish astronaut a couple of weeks back, he was giving a seminar in Helsinki, and I ask him this Did he have the feeling it was actually working on the outside of the International Space Station installing one of these solar panels? Did he have the feeling that it got smelly in his spacesuit? And he said that you were so busy doing everything that you didn't notice? But some of his colleagues remarked about the smell all the time in the space station. And apparently when you look at web streams of astronauts returning to the space station when they've been there before and then come back, it's always the first thing they say. When they enter the space station, they remark on this man are the Iceman. It's apparently very characteristic smell. Wow. Yeah. Sadly, most of us will not be able to experience it, but apparently it's legendary. So let's leave it at that again. Next question When scaling up from space stations to bigger habitats like Mars colonies or even O'Neale cylinders, does something fundamental changed about what to consider and how to build life support systems? Well, there's already some questions that need to be addressed in scaling up from what we have now. Like we have, for example, the The Dragon capsule that just wants to fly for three days, go to the east, go back to Earth. That's it. So there you don't need to consider much. You just built a scrubber and you have oxygen bottles and you've got, of course, this still needs to be reliable and work very well about that's that's where we are right now. The International
Space Station is almost completely reusable in terms of its life support system. But the problem with that is it's still designed as an experiment platform. The system fails from time to time, and then they had problems that they need to change to the Russian system instead of the American. Because something breaks here, something fix that. One thing that you really definitely want if you fly to Mars or if you have colonies, you want the system to be fail safe, you need to build it tested. It's serviceable. You need to build it such that it is redundant enough and that it well, ideally that it cannot break down. And that is one additional advantage of plants because plants don't break down. If one dies, the next one goes in its place as long as you don't poison their whole life support system altogether. You'll be able to just scale about by just giving it more place to grow. So these systems, if you want to have more like you growing or you need to put an additional bottle there, put some lights up and you can grow more of it. So that is something that is an active development because people want to fly to Mars pretty soon. I mean, you know, Musk keeps talking about it in the next five years. But nobody has proven yet that there is a life support system that is reliable enough to actually get you there. You don't want to strand halfway with the non-working life support system. And then as soon as you are on a planet and as soon as you can plant stuff in the ground, then there's no reason not to just go for bananas with growing plants literally full bananas. I suppose there have been experiments with strawberries growing in lunar soil. As long as you give them water and a little bit of nitrogen that they grow in lunar soil just fine. Then you have Martian dust equivalent studies of people trying to grow stuff on Martian soil, and that apparently is also something that is possible. So then you just need to go there and start growing things. And as soon as you have an
ecosystem like like the closest ecosystems that we've seen on Earth, we have eight square meters per person. You can just scale up by getting eight more square meters per second person. As soon as you have a life support system where you have eight square meters of plants growing for one person, you can just scale it up by adding another eight square meters and you have capacity for a second person. Mm hmm. Premeditated brings us to the to the next. Question. Yeah, I think maybe you've answered this already. I'll just read it out. Why is the entire system set up in one place seems to be super dangerous, single point of failure? Why not have multiple smaller systems so lots of one could be compensated by sealing off a part of the station? And yeah, I think that's essentially what you just said right now. Well, on the access, there is the big system that I've showed. That's the American system in the military that does most of the work for the station. But the Russian part of the station also has a system that works in pretty much the same way. It's not quite as redundant. So if anything were to happen, you could seal off the American pot and run with the Russian system. Since the last five years, there's also the European advanced closed loop system that has the bioreactor attached, and that's in the Columbus module. So that's again on the other end of the station. So right now, there are three redundant life support systems running on the space station. Of course, the advantage of having it all in one place and together is that you can more easily feed stuff from one system to the other. If you want, for example, your water to come from your toilet into your water recycling system, and from there you want the hydrogen and the oxygen to go further into other systems. So it's always a design question how much redundancy and fail safety do you want and how much compactness of the system do you want? I suppose it's similar like any other. Yeah, the audio is again break
ing up a lot. I think I will pick one last question here and then we'll wrap it up. Also, time starting to run out. So last question that I'll pick so someone would like to know if due to the growth of surface and square and the volume in Cuba, it gets easier or harder to create and maintain the life support system on spacecraft. Some. Well, interesting question. So in general, as as. There are more people you just need more life support system, a bigger system, or you just build more smaller ones. So that should not be fundamentally a problem. You just need more of them. I would assume that the bigger systems in general have high efficiency because you can just devote more space to smaller things to do more little cleaning assemblies and so on. But then on the other hand, you need more redundancy as well. So that's actually a very good question. Then there's also one thing now that I still have to slide up here, the numbers I have here oxygen, food and water requirement, these are given by Nassau for the standard crew member. So that is for one human male. Nassau always calculates this in terms of human males. On average, female crew members have lower metabolic rates, so they use less calories. They also use less oxygen and less water proportionately. So actually, it makes no sense that muscles since a majority of male astronauts into space, all the other space agencies as well because women simply consume less resources from their life support system perspective. So if you wanted to make an argument, why you should a crew of women to Mars, this is your argument here. They would use less like support resources. Yeah. Well, yeah, that's a pretty big advantage right there, like you can't argue with with that, you know? Cool. So I think we will wrap it up here. I see that you're also active in the IOC trend, so if you have any more questions, feel free to hit up the IOC trip. Maybe you can stick around a little bit and answer some more questions there. I'll also be w
alking around the world in the cases where it works. Yeah, great. So if you catch us, if you catch or somewhere there hit them up about the audio issues, I'm very sorry again. We do have some back up recording. Probably we'll take a look at that and see if we can fix the audio. So hopefully in the final release that we will make to media CCC, the E the audio will be a little bit better again. Sorry, but yeah. Well, thank you very much. I'm very honored that we were able to show like the first part of the trilogy about Epic Space Adventure and what they need to do to make that happen on our stage. Thank you a lot. And. I hope we'll have a great I'll see free for the rest of the day.
