Keeping all of our planets clean

Hi everyone and welcome to Space Cowboys, number... I do not know. I do. I'm keeping count. It's number 17. 17. Wonderful, wonderful. Welcome Thijs. Welcome Herbert. Would you care to introduce our guest today? Yes. It's Gerhard Kminek. Is the pronunciation right, Gerhard? Perfect, Dan. Okay, lovely. Surprised. And you are the Planetary Protection Officer of the European Space Organization. And we're so happy to have you here because we're talking about planetary protection, well, not all the time, but every once in a while. Yeah, very often. Yeah, we... I first heard of your position, I think, a few months ago on this show. For instance, with Daniel Masson, when we were discussing space law, somehow this popped up. Yeah. And it popped up several other times. So we started trying to have you here. And we succeeded. Yes. Well, thanks for having me. I'm glad to be here with the space cowboys. Yeah. And what is a Planetary Protection Officer? Well, it's a fancy title for a... Well, I wouldn't say regular, but it's a standard function that several space agencies have. We know NASA has one. Yes. And the other space agencies? Yes, the Japanese Space Agency just introduced also this function a year or so ago. Okay. Because they started to explore other avenues for their... with their missions. And they realized they also need this function. So they contacted actually us. They contacted me and asked, okay, how should we set it up? Yeah. And we gave them some advice. And now they have set it up very similar to the way we have it here. And it works very well. And what is it? Because you're not protecting our planet. You're protecting other planets. No, actually. There are two rationals for planetary protection. And one of them is to protect Earth when we bring back samples with our missions from another moon or from another planet. Yeah. So when you bring something back and you don't know what's in there, you have to be cautious. And this started, I remember, in 1969 when the astronaut Neil Armstrong and his crew came back from the moon. They went into quarantine. Yes. Because you're afraid that maybe some alien... Some alien being might come here and devour us all. Like bacteria or whatever. I wouldn't put it in that drastically, but... I do. I like movies. Yeah. But you have to be cautious. Yeah. Yeah. Whenever you bring back something, you have to be cautious that the material you bring back from a moon, our moon or other moons or a planet, is not a problem for the people that handle the material. So that would be an occupational risk. Bad, but, you know, to a certain degree. Yeah. And that's acceptable. And then you have to, of course, be even more careful to make sure it has no effect on the public or our environment. Yeah. So we covered several aspects for the Apollo missions. You correctly pointed it out. For the first three Apollo missions, they applied strict quarantine procedures for the material and for the astronauts. Not much was known about the moon at that time. Okay. Today, we look back and say, okay, why did you do that? But thinking back, what was known before the Apollo... It was certainly sensible. It was a sensible way to do. We had no clue if there was anything on the moon. Right, right. So they looked, of course, for the radioactive elements and chemical hazards and biological ones. Yeah. And the biological ones, they fall under the umbrella of planet protection. Yeah. So this is one rationale for planet protection. When you bring back something to make sure it has no negative impact on our environment here on Earth. Yeah. Yeah. Yeah. Yeah. Yeah. Yeah. Yeah. Yeah. Yeah. Yeah. Yeah. That's the second rationale. And the second rationale is to make sure that we don't compromise our search for extraterrestrial life in our solar system. So when we explore other moons and planets, we control the biological contamination or the contamination that we bring with us that could compromise this kind of research. Yeah. We basically want to prevent, if I understand you correctly, that in 30 years, we will be on Mars and... There's life! We're like, oh my God, we have found life. We have found life. And then it turns out after years of research, it's actually us. Yeah. It carries our flag. Yeah. Exactly. It would be not a good return of investment to put it in that way. The bummer. Oh my God. Imagine the headlines. And just as we know it. Yeah, exactly. Yeah. But, and that's, I think, important to point out because sometimes it is not described correctly. And also the name is misleading. I have to confess. Planetary protection. Yeah. I think it's something that we should be aware of. It's a very, very important point. Yeah. Yeah. So, the second rationale is not there to protect any moon or planet in our solar system for their own sake. Okay. Or because we are nice. It's a purely selfish interest to protect our scientific investigation related to the search for extraterrestrial life. And by doing that, of course, we protect these environments because we don't want to get false positives. But the main motivation is a... Yeah. The main motivation is a relatively selfish one. Well, great. It's very nice of you to point that out. Yeah. It's great to have you here. And we're going to talk all about that and how you do that. And I got so many questions. Yes. But first. Yeah. But first, we have a whole bunch of stories of the week because last week we said like, hey, let's postpone a bunch. And I'm kind of amazed it was only a week ago because indeed a lot has happened. You have a whole bunch in your list. I have one. And that's the one that I'm going to talk about. And I'm going to talk about the one that I'm going to talk about. And that's the one that I'm going to talk about. And that's the one that I'm going to talk about. And I'm kind of amazed it was only a week ago because indeed a lot has happened. You have a whole bunch in your list. I have one. And then we got another one, but we'll talk about that. Herbert, I assume, how do you pronounce it? Bereshit? I'm going for Bereshit. The Israeli moon lander, I assume it's on there. It is. Yes. What happened? It's only on there because it's not. It's on the moon too, but not the way that was intended because the poor thing crashed. It was an Israeli moon mission. Israeli moon mission carrying lots of stuff, memorabilia from Earth. It was the fourth country putting something on the moon. It was going to do a soft landing and well, the whole Israeli nation would be celebrating and all that. And it crashed. Yeah. Very, very sad. Never mind. Nevertheless, they did get their lunar XPRIZE of a million dollar or something. Okay. Do you know the exact amount, Gerhard? I don't know exactly. No. Okay. But they- They won a prize. They qualified for a prize anyway. Okay. Having reached the moon because they did. Yeah, they did. In a very particular way, right? They didn't just go straight there. They sort of fell, let the thing fall back to the earth a whole bunch of times to get closer and closer and closer to the moon. Yeah. It was like pushing a swing and getting higher every next swing. Yeah. So they did orbits wider and wider until they were wide enough from earth to fall towards the moon. Yeah. And just alone in that, it was already a proof of concept of just really cheaply being able to go to the moon. If only that rocket- That's right. It was a land- Commercial flight as well. Commercial flight, right? Yeah. If only that one engine would have worked, it wouldn't have crashed and it would have been a success. Yeah. Well, that's the whole idea. Your hardware has to work. Yeah. It's a good point. The thing has to work. So that ended in a failure. That's too bad. Okay. That was a failure. Yeah. Maybe that's a good point to have you talk about the Falcon Heavy. Oh, the Falcon Heavy. Yeah. Because that was a success, I believe. And a little failure. And then it kind of wasn't. So the big challenge for Elon Musk's SpaceX was this time to nail the whole thing, put an Arab satellite. Yeah. A communication satellite, I believe, in orbit, land the two side boosters, but then also land the center core on a drone ship. And it did all of those things perfectly. And so it was a big success. Great. It's like, wow. Then they started sailing. Yeah. Really beautiful. And then the only thing that needed to happen was get that rocket back to Florida. And then it hit rough seas and the center core toppled over. And landed at the bottom of the ocean. Makes you scratch your head, doesn't it? I mean, you're at sea. Yeah. Okay. For Christ's sake, tow it or something. Yeah. I mean, it is a drone ship. You can imagine that they could also just have a ship nearby that at least the landing itself, you know, is in some sort of way controlled automatically so that when it blows up, you're not close. Yeah. So it's a little bit of a surprise. Yeah. But then, I don't know, secure it or whatever. Maybe that's what I liked about the previous Falcon Heavy launch a year ago was that it was a gigantic success. They launched this Tesla Roadster. Yeah. Because they launched the Tesla Roadster. The rocket works. They also put like a whole bunch of funny art in there to sort of inspire the world and grabs the world's attention. Play the right kind of music. Exactly. Play the right kind of music. All those jokes and all that fun was all part of it. Yeah. And mission-wise, the center core didn't land. So you could also even say that as an experiment, well, it was mightily successful because there was still room for improvement. And now again, there is still again room for improvement. That's true. So that's nice. So they learned something, I hope. If I was also, I don't know, YouTube was pushing this one video on me all the time. NASA's director, Bridenstine, was also saying that... They're now really looking into using the Falcon Heavy to get to the moon in 2024 on that crazy mission that we talked about a few weeks ago. Yeah. Where they want to... With the passenger. Yeah. They want to put a man on the... The Americans want to put a man on the moon again or a woman. Well, first they're going to circle one round the moon and back. Oh, I missed that. Yeah. This paying passenger. Okay. Oh, I didn't see it. Yeah. Maybe. As far as I know. Okay. We'll use the Googles. We do. But now at least he said that the space launch system that they were developing, I think the quote was something like this, nothing's off the table, we're really looking into it. I mean, it would be kind of silly if he wasn't because if it's much cheaper and a better option, I believe in connection with the Orion capsule, Falcon Heavy, that's what he said. They're looking into that option. Okay. So it's a huge success still for the Falcon Heavy. Yeah. All right. So... You had... You had some more on your list. Yeah. I have more failures as well. Oh, failures. Okay. Because there's an Intel sat geostationary satellite in trouble, Intel sat 29E. And it's really weird. There's video. I found it on Ars Technica. I'll put the link in the show notes. And you see the satellite emitting fumes and doing strange weird things. And one thing is very clear, it doesn't work anymore. Okay. So there's a satellite up in geostationary orbit and it's suddenly started to, well, not exactly explode, but leaking stuff. And nobody knows what's happened to it because you can't look that closely. But a couple of things like this have happened in geostationary orbit lately. Mm-hmm. Let me see if I can find it back quickly. Mm-hmm. Okay. During the last two years, I'm hitting the right sentence here. During the last two years, satellites such as AMC 9, Telecom 1, Amos 5, Eutelsat 33B, Echo Star 3 and Galaxy 11 have all experienced on-orbit anomalies. Hmm. So there's something wrong in geostationary orbit. That's not good. Yeah. So that's all I have to say. I'm going to do this quickly. Yeah. But that's… You want to talk about planetary protection here. I'm so excited. Another story that we should mention is the story of Scott Kelly. The story of the Kelly twins actually. Oh, yeah. I did see something about that. Because the guy went up into the ISS, stayed there for a year and they researched everything. I mean, they took his blood a thousand times. They took his stool a thousand times and everything. Maybe his sweat as well. And did the same with his brother down here on Earth. Mm-hmm. Mark Kelly. And they compared everything. And what I found fascinating is the headlines about this research depended very much on the perspective that the medium or the journalist had to begin with. I mean, one headline was like, long-term space flight can be done. Yeah. And the other one might read, long-term space flight is as dangerous as we thought. Yeah. Really has an influence on people's bodies, right? Yeah. Both are probably true. Yeah. But that was really fascinating. It's fascinating because they could really compare these two people. Yeah. Yeah. Although… One on Earth. One is still one. Although it's two… Yeah. …only one set of twins has been studied. Okay. Yeah. Good one. Good one. That's one sensible conclusion that I read someplace. Actually, they should do this on many more twins, many more sets of twins before you can really say something about the long-term effects of space flight. Yeah. So that's one more. Mm-hmm. Then we have… Let me see. Yeah. What else happened? Amazon is also now up there among the companies that want to establish a space flight. Yeah. Yeah. Yeah. Yeah. Yeah. So, there's a space network to supply internet, to provide internet to Earth. Yeah. So, now we have… SpaceX? SpaceX. We have OneWeb and we have Amazon. Yeah. And then we're not even counting Hiber… Yeah. …which is doing an internet for Internet of Things. Yeah. For Internet of Things. Low bandwidth and everything. Yeah. But the other three do high bandwidth… Yeah. …for people. I mean… And so, it will mean a global broadband… Yeah. …access… So, this… And… …anywhere you are… …in the world. …competition, low prices, high quality… I would assume it would be almost as revolutionary as the difference between dial-up and broadband. It's just a completely different ballgame… Yeah. …when it comes to internet. So, Amazon is getting in there as well… Yep. …using their own rockets. I would assume Blue Origin. Yeah. Only two things have to happen now. The satellites have to really be launched because I think SpaceX is going to be the first one to launch a satellite. Yeah. Yeah. So, that's the… Yeah. …the first one to launch a satellite. Yeah. Yeah. Yeah. Yeah. So, I think SpaceX has done two. One web maybe six. I'm not exactly sure. Okay. Do you know it, Gerhard? Okay. And we need the hardware on Earth, of course. We need the handsets. Yeah. Yeah. All right. Last one is the company called Relativity Space. Okay. Yeah. They manufacture and get this, 3D printed rockets. 3D printed rockets? Yes. Yes. It's metal, some kind of metal. You can 3D print metal now? Oh, I didn't know. Go to… Yeah? You're saying yes? You can also print metal? I'm going to take on the story now. Anyhow, they… And it's not just a plan. They got their first contract. Okay? That's the story. Okay. Ambitious rocket company Relativity announced its first customer on Friday, the global satellite operator Telesat. For… Well, they're probably going to test it out first. Friday was… Before they… Before they… Yeah. Before they shoot it up. Sure. Sure. Sure. I'm not hitting upon the right sentence now to find the… What, the launch question? It's probably going to be… I will see. What else could it be? Yeah. What else? It has to be light. Yeah. Gerhard. So… We asked you to bring a story of the week as well, I believe. Yes. You have… You just have a very good story. I was asked yesterday… You have the story of the decade. No, exactly. Nobody told me there has to be a recent one. So… Sorry. I just realized you had your 17 show here now today. Mm-hmm. Mm-hmm. So, okay. I talk about a mission that ended in 2017. Okay. Oh, yeah. Yeah. Fair enough. Which is fine. No, it's about… We never reported on that one. So… Yeah. Why not? Good. Good. I think it's worth reporting. It's about the Cassini-Huygens mission. And it actually goes back decades before that when I was a kid and thought about space. The most… The biggest impression I got at that time was looking through a telescope. Yeah. Yeah. Yeah. I was looking through a telescope and seeing Saturn. Because if you see Saturn with the ring at the right angle, you get a really nice appreciation of the three-dimensionality of a planet in space. Oh, yeah. No other planet can give you that. So I was always fascinated by Saturn. And then, of course, we had this… How did you look at Saturn? Binoculars or naked eye? No, no. A real proper telescope from the observatory. Proper telescope. Yeah. All right. Okay. But I was still at school at that time. Sure. So then… Yeah. So then we had, of course, in… When was that? In 2000… No, in 1997, they joined NASA ESA Cassini-Huygens mission to Saturn. And the Cassini spacecraft carried our lander that landed on Titan. Very interesting discovery it made there. The Huygens probe? Yeah, the Huygens probe. Still keep us busy today or the scientists busy today. And just a few weeks after that, the Cassini spacecraft discovered these jets coming out of Saturn. These jets coming out from Enceladus, another moon of Saturn. And there was always speculation about having a subsurface ocean there, similar to some other moons in the Jovian system and Jupiter system. Yeah, like Europa? Europa, Ganymede. But it's one thing to have an indirect evidence. It's another thing to have direct evidence. So for the Cassini mission, it came very nicely. Sure. So you had jets coming out of ice, silicates and interesting chemistry, which was measured by a joint US and European science team. And you had then also other measurements by the spacecraft confirming that there is a subsurface ocean there. So it's… I found it interesting even today after the mission is over. It entered this… Yeah. Yeah. It entered this… To the moon of Saturn in 2017 to avoid crashing on Titan or Enceladus. So it's not sticking around as long as the fuel is still there, was actually a planetary protection requirement. Oh, can you explain that? So… Yeah. I mean, if, if you're in a Jupiter system and the Saturn system, there are moons there that are interesting because we want to learn more about the origin of life and extraterrestrial. terrestrial life. Now, on Mars, of course, Mars is very interesting, but looking today at Mars, it's a desert. And we're really looking desperately also for evidence of liquid water that is not billions of years old. That evidence is very clear. You just have to look at the planet. But something that is more recent, very difficult. Mars Express, another mission that we have launched a long time ago, has now found very nice evidence of liquid water, but it's very deep. So very difficult to get to. Now, on these moons in a Jupiter and Saturn system, if you fly around there and make your investigations, at the end, you have to make sure that the spacecraft doesn't crash on these moons and contaminate these moons. Because again, if you look for evidence... If you look for evidence of life, we don't want to find our own life, like you said at the beginning of the show. And there are two ways to deal with that. Either don't crash there. That would be good. Yeah. Or you control the biological contamination. So for Cassini, the approach was we don't crash on the moons. And so the final fate of the Cassini spacecraft was not to just hang around as long as the fuel is there. And then suddenly, you know, it's dead and you cannot control it. With a potential crash on one of the moons. No, the decision was because of planet protection review, decommission the spacecraft and you actually move the spacecraft into an orbit that will then enter the Saturn, the planet. And that will end the mission. Now, it did some fancy things and the scientists got happy. But this decommissioning was because of the planet protection rules. That was definitely a part of it. So the idea is... You choose to decommission it the way you just described. And if you do that, you don't need to sterilize it before the mission begins. Oh, really? So even way before that was already decided on? Yes. That's the critical thing here. Like I said, to control the contamination, you either don't crash or you control the biological contamination on a spacecraft. That has to be decided. So you have to decide at the beginning when you start to discuss a mission. When you... Way before you build any hardware. And so this spacecraft, the typical spacecraft build takes several years. Our big missions sometimes have a lead time until really they're launched over a decade or so. And then especially if you go to the outer solar system, there's another... A decade or longer of flight. And then they start really the mission. So all the way back, you have to decide what do you want to do. Yeah. One or the other option. And is this one option sterilization beforehand, is that a very difficult thing? Is it very expensive? I mean, apparently people decided not to do that and do this decommissioning thing. Well, if I can... Does that save a lot of money? Yeah. For what? Yeah. Well, can I add... Yeah. Yeah. I would like to add to that question because the Huygens probe did land on Titan. Yes. Yeah. I believe you said it's 10 years old, but back then Carolyn Porco, the head of the imaging team, I believe she said it was that landing of the Huygens probe is something that should have been celebrated with ticker tape parades on Broadway in New York. I agree. Yes. I agree fully as a monumental moment in human history. It was an amazing, amazing mission. So the more we talk about that mission, the better. But in that case, you knew you were going to land on a body. So to tie in with the question that Herbert asked, how do you do that? How do you sterilize something for a mission like that? Yeah. And I use the Mars example because it's more... We have more examples. Yeah. And we have some that are very recent and some that will come... Come up hopefully next year. Again, there's a choice. There are some orbiter spacecraft. So spacecrafts that we send to Mars or other planets that are designed not to land, but to fly around the planet or the moon and do the scientific investigations from orbit. Yeah. Like Cassini itself. Yes. Yeah. Now, for this type of spacecraft, we can either select the option of not crashing. Yeah. Which means that a spacecraft has to be very reliable because we have to be able to control it all the time. That has an impact on how to build a spacecraft, how to build the hardware, how to build the software, how to operate a spacecraft. That's an impact. It's not for free. This also costs money. If you have a higher software category to make it more robust, it costs more money than a lower software category. If you have more redundancy in the systems, more bandwidth... Backup, that also costs money. Now, there are some of these spacecrafts that on intention go lower. They have a lower orbit, which is not that stable. One example is the Mars Reconnaissance Orbiter that is flying around Mars right now. It's a NASA mission. For scientific reason, they want to go lower. And they say, okay, I go lower because I want to measure something. There's a good reason for that. So, with all what I can do to make it reliable and operational reliable, I cannot guarantee the level that you require. So, it lands on your desk, this question? In that case, it landed on the desk of my colleague at NASA. And for that, there's an option. There's another option, and it is to control the biological contamination of the spacecraft, even for an orbiter. And if you have a planet like Mars... Yeah. Yeah. Yeah. Yeah. Yeah. Yeah. Yeah. Yeah. Yeah. Yeah. Yeah. Yeah. With an atmosphere, it is actually helpful. Yeah. Because when you go through an atmosphere, you have a heating event. And you can use this, we call it burn-up and break-up event to sterilize part of the spacecraft. Not all of the spacecraft because there are some things that come off early enough and don't get very hot during their fall towards the surface. So, some things you need to control. So, some things you need to control before launch in terms of biological contamination. But most of the spacecraft actually get heated up to very high temperature during this process. So, this atmospheric entry, you can use an MRO, the Mars Reconnaissance Orbiter, will use that. Yeah. So, even for an orbiter, you have both options. Now, if you're a lander, you have one option because you want to land. So, for a lander, you have to control the biological contamination. And there are various ways to do that. Like how? Well, like we discussed before for the Cassini mission, it starts really very early. When you have the first idea about a mission, when you discuss it internally, not even going out to industry, you have to think about this aspect because it permeates through the entire flight system, through all the engineering domains. You need to design. You need to design a spacecraft such that it can be sterilized. Exactly. It's not something that you build your spacecraft and then say, excuse me, now I have to sterilize it. Put some alcohol in it. Yeah, exactly. That doesn't work. So, you have to design it with that in mind. And if it's done properly, the impact is quite reasonable. It's not easy because the spacecrafts are quite complex. And we have a lot of suppliers from outside and this needs to be managed properly. But on several instances internationally, so NASA, JAXA and our side, we have demonstrated that this can be done. It adds complexity in the design. Like you said before, it adds complexity in what equipment you can select. Oh, yeah. And how you build the spacecraft. Do you remember a recent example of the past decade of something that you really had to think about? That's something that was hard. One of the missions that we might know? Well, it comes up almost continuously when you have missions that are prepared for like for Mars. Well, now we have another one that goes to Europa and Ganymede. The Chus. The Chus mission. The Chus mission. Yeah, in a few years. Yeah. And there you have to start at the beginning. And then it's a continuous process because you invite industry to bid for the mission. And then they have their suppliers and they open then the calls for the suppliers of the individual elements. So, yes, you set the rules at the beginning. But then you have to monitor that the rules are really permitted through all the supply chain. Yeah. And everybody's understanding these requirements because for a lot of the players, they are still relatively new. And then you have to monitor it during the process of building the spacecraft, testing the spacecraft, shipping from A to B to C to D because the spacecraft is not built in one room up to the launch site, including the rocket. Yeah. And can it get contaminated along the way? Yes. And then you have to clean it? Or something? Yeah. That's the problem. If you build a spacecraft, it gets very quickly very complex. So there are lots of things that you cannot access anymore after a certain step. Okay. So you can't say let's wait with the whole sterilization until the whole spacecraft is assembled. No. In some cases, some parts you have to sterilize before they disappear in the interior of the hardware. Exactly. In the guts of the spacecraft. Yeah. So. Everything that usually is used to build a spacecraft, starting from the screws and the washers to the individual components on an electronic board, that's where you start with the cleaning. That's where you start thinking about is it compatible with the processes I want to apply? Maybe 80%. The answer is yes. For 20%, the answer is maybe no. Then, okay, there are several processes we can use. Look at the other processes. Again, you will have. Processes for sterilization, you mean. Processes. Because I was about to ask what techniques are used to do this sterilization. Because we were joking about it just now, alcohol, heating. Yes, yes. Just tell me. You're absolutely right. What's the repertoire? First, I try to avoid usually to use the term sterilization because it's maybe a little bit misleading. What we try to do is to reduce. The biological contamination to a level that we know and to a level that we can measure. And that begins to answer another question I had. I keep calling it sterilization for some time. Can it be perfect? Actually, you're saying no. No, it's always related to a reduction process. And the same is true also when you apply this process. In the pharmaceutical and medical industry. You start with a certain contamination level that you need to measure. And then you apply a process that you have validated. And there are several processes that are validated for a tenfold reduction, hundredfold reduction, ten thousandfold reduction, one millionfold reduction. So you start with a known value. You know where you want to go to. And then you pick the process and you pick the parameters. And then you pick the parameters of this process to bring you from the starting point to the end point. Right. And so the processes we typically use are first cleaning processes. And again, this is true also for the medical field. You cannot sterilize something. I also use the term now because I think it's just more. Yeah, we do it anyway. Yeah. You cannot sterilize or bioburden reduce something if it's dirty. That's why. Yeah. Yeah. Yeah. Yeah. So the hospital, when, you know, after surgery, they first put everything in the dishwasher to clean it from the – well, to clean it. Yeah. Well, okay. Blood. Blood. Whatever you have, the debris. And then you can expose it to a sterilization process. So first we clean it and we use different solvents for that. Alcohol, different forms of alcohol, alcohol-water mixes, acetone, hexane. different solvents are used in these processes tailored to a certain degree to the hardware. There are some things that cannot deal with water. There are some things that cannot deal with hexane. So there are some flexibility. Electronics, water, don't mix. Actually, it works, yes. But it's always the question at what step you inject this process. Because, for example, if you build a board, you might say, okay, the electronic components, don't worry. You can clean it with this and this solvent. Yes, but then you put on the board a conformal coating. This is this gooey stuff that you see sometimes on these electronic parts. Well, that's a different story now. Because some of that does not like water. It starts to swell and actually some deterioration happens. So you have to know that and you have to know when you inject these cleaning processes. So that's why you have to go really into the details. But typically, we start with solvent cleaning. And then we use one or more of the, again, I call it sterilization modalities. Heat is the predominant one. Heat. Yeah. Typically, a temperature is 125 degrees Celsius and for several hours. Depending on the complexity and size of the part, it can be hours, three hours. It can also be almost two days at that temperature. If that doesn't work or if items are not compatible with this process, we can use gas processes. Hydrogen peroxide gas process, for example. Okay. Ethylene oxide gas processes. All of them are also used in the pharmaceutical industry and in the medical industry. Another one that is a lot used by our Russian colleagues is ionizing radiation, gamma radiation. UV? Gamma radiation. Yeah. No UV. UV is tricky. Ionizing radiation is very penetrating. So if I have a structure, I put your laptop in there, it will easily penetrate the entire structure. For UV, it's only working at the immediate surface. Sure. So if I have a shade, it's already reduced. If I have a couple of dead microbes on top of another microbe, protection is happy. It doesn't see the UV. So UV can be used if the item is controlled, very well. So if it's cleaned carefully before, so that you make sure that there's no shading and there's no buildup of contamination that could protect from the UV. Yeah. How much contamination is there? Like, is it teeming with microbes, even in a space that seems relatively sterile? Well, the clean rooms that we use, the bioburden-controlled clean rooms that we use for assembling a spacecraft that requires this kind of control, is around 10%. So it's 100,000 to 100,000 times cleaner than the typical manufacturing environment. Well, in order to do that, and we still have people in there. Yeah. So in order to do that, of course, you need to have a special air conditioning system with filters. Special clothing. And special clothing. And that's very important. It's a full body clothing. So the only thing that looks through the clothing are your eyes. And then you have to have a special clothing. And then you have to have a special clothing. And if you have delicate operation, you also have to actually cover your eyes with goggles. Several layers of gloves. Two layers, typically. If one layer breaks, then you still have another layer and change it. So that's how you work then, when you build and test a spacecraft that requires this kind of contamination control. Now, I have another question. Because you explained you choose a certain level of cleaning. Yes. And that helps you. You choose the right technique and everything. But on the other hand, when you're going to space, you're going to some celestial body like a moon of Jupiter or Mars or whatever. You just told us you want to prevent our kind of life being put there. So I would say anything less than perfect is actually useless. Am I wrong? Yeah, that comes back to the original point I make about the rationale for planet protection. Yeah. We don't... The planet protection rules I emplace not to protect the moon or the planet from colonization. They are there not to compromise our measurement. And the space environment is actually quite harsh. Yeah. So in essence, what we do is a risk assessment. We say, okay, if we bring that much contamination, what is the risk? Going to this planet or to this moon, that this level of contamination at this mission or in a future mission could compromise my science. Yeah. And that's why the acceptable levels also differ. If I go to Mars, it's one value. If I go to Europa, for example, or Enceladus, it's more stringent. Why? Because if I put some contamination on a desert, it's a different story compared to putting some biological contamination in an ocean. Somehow you have to factor in... It's the perfect environment for distribution. Yeah. You have to factor in the probability that our life that we bring there will multiply. And that's why it's not only... What we do is not only counting how many bugs do we have on the spacecraft or in the clean room. Also what's going to happen. But also who is there. Yeah. We use actually molecular tools to investigate what type of contamination do we have. Is this a type of contamination that can survive our cleaning processes? Then we have to adjust the cleaning processes. Is this a type of contamination that would survive the launch? Which is a very tough environment when you go from... Okay, we have different launch sites. Ours in Kourou is from a jungle. Or you go from Florida. Which is also a hot environment. You go from Baikonur. It's a desert. In eight minutes, you go to the hard vacuum of space. Not that many terrestrial microorganisms can deal with that easily. So that all factors in there in the assessment what contamination can I accept on a specific mission. It depends where you go. Yeah. And you've been Planetary Protection Officer since 2004? Yes. Were you the first? One? At ESA, yes. We had a function that a colleague of mine carried out before that. But we didn't have that many missions. So it was not a unique function, a unique job. Full-time job. Exactly. It was just a side activity. But the function existed already before. When I came on board then, we made it a full-time job. We started... That was the start of the Aurora Exploration Program. Uh-huh. Okay. Where we had plans to... And ExoMars is actually one of the consequences now. Oh. To go to Mars, to do a robotic mission to Mars, to do a sample return from Mars, and to prepare human missions. So that this... Yeah. And you did that also work on Rosetta? No. Already launched. Almost already launched. Yeah. Right? Yeah. Has there been a lot of evolution in the ideas of what planetary protection should look like? Such as this whole procedure of cleaning and sterilizing spacecraft during building? Well, the rational... The two rationals aren't changed. They have not changed for half a century now. How to do it has changed, of course. First of all, when we... The requirements we have for planetary protection are not cast in stone. We review the requirements on a regular base at an international level, and coordinate them. We have to make sure that they are well-coordinated between the space agencies and with the science community. To take into account what we have learned. What we have learned from the moons and planets in our solar system, and also what we have learned from life on Earth. Yeah. So, depending on that, we adjust the requirements. And that can go in one way or the other. Can you mention one or two changes that have taken place, like in the last decade? Well, what happened in the last... It was a little bit more than a decade, but not much more. Mars. Mm-hmm. The idea about life on Mars, well, had its ups and downs over the... Yeah, a hundred years ago... Over the decades. The little green man, the canals, the civilizations. Yes, yes. Schiaparelli and a lot of high hopes. High hopes. And then the first picture... Big disappointments. Big, big disappointments. Still Viking, the two Viking spacecrafts, extremely capable machines... Mm-hmm. ...were sent to Mars with a clear intention to really look for life. And, okay, the results were mixed. I would say that even, especially from today's perspective. And then there was, at that time, the interpretation of the result was, okay, sorry, we haven't measured anything. There's nothing there. Yeah. Today we would interpret it a little bit differently. But at that time, that was the response. So there was then, as a consequence, no Mars mission... Oh, yeah. ...for more than two decades. Yeah, because... Almost three decades. People almost expected back then that they would find a planet that might be alive, but a lot more... I have never known Mars anything different than a big red desert. Yeah. But back then, there was... It was all up in the air. Like, maybe you'll find civilization. Yeah. Maybe... Who knows what you'd find? And the disappointment was so big... It was big enough not to have missions for a long time. ...not to have missions for a long time. And then people discovered different things. First, after sending, again, spacecrafts to Mars, they realized Mars is not one environment. They're like on Earth. There are different environments on Mars. Some... Okay, some look more like a desert and would not be conducive for life, but there are other environments that could maybe support not only terrestrial life to survive, but even to propagate, multiply. So that was one aspect that came on the table. I just mentioned gullies here. Gullies were discovered... discovered by imaging from orbit. These were on steep cliffs. There was evidence of water coming out. Yeah, and streaming down. Yeah. Yeah. Especially for some orientation towards end of the right season. So the evidence, the morphological evidence from orbit was, okay, there's something that is not... three and a half billions of years old that's more recent. So there might be a chance to have something there that could still be active. On the other side, we discovered here, in our oceans, on Earth, that something what we have sought originally, the deep sea being a desert, is actually teeming with life. So that was the time when the hydrothermal vents were found and also life around the vents. So that all came together and people looked again at the requirements. At least we have to be a little bit more careful. So we put zones on Mars where we have confidence that, okay, it will not be that problematic. We have a certain contamination level that we can allow. And then there are some unique features where we just today don't know enough about so that we can clearly say that is not a problem. So for these features, we make sure if a mission goes there, it is cleaner. Clean enough. And so a concept was born, the special regions on Mars, that actually puts now a zoning on the planet. And that was one thing that changed the requirements for part of the planet. It made it more stringent. Now, since then, we have many more information from orbit and the gully features that were seen originally, there were several types of these gullies. They were all put in the special region box. Since then, we know some of them had nothing to do with liquid water. So they were taken out of this box. So that's another, it's just a normal evolution of science. But there was another example of, okay, we change it. And this time we relax it for this kind of targets. Yes. And so, like you said, the idea that we're not contaminating Mars and maybe, you know, with a microbe that might eat the life that's there, that's almost like a secondary objective. If I understood you correctly. Yes, yes. Like I said, I mean, one of the rational is really to protect our scientific industry in the search for extraterrestrials. Life in our solar system. And just to not compromise it means, yes, we protect the planets and moons to a certain degree. But with this motivation in mind. Yeah. And it could be in two ways, I believe that on one hand, your instruments itself could be contaminated. So you're just looking at life from Earth. And it's just like a dirty lens almost. And the other thing is that you maybe leave something behind that replicates over the years, over the eons that you will then find again. Exactly. Those will be the two ones. And it's a good example because right now, we're building a spacecraft that is again looking for life. The first one since Viking, since the two Viking missions, that has a clear scientific objective to look for life on Mars. And this is the ExoMars 2020 mission. So we plan to launch it next year. And not just the indirect stuff such as, is there any water present? No, no, no, no. Really looking for the organic molecules that would indicate that there is life. And for this instrumentation and for everything that actually brings the sample to the instrument, we have to make sure that it's much, much cleaner than a just normal lander. Like the cleanest thing you've ever made. So this instrument cannot, these instruments and the assembly of the instruments in the chain of systems that handles the sample, that cannot be built by people in the room. So for that we have actually stainless steel glass glove cabinets where people go with gloves inside and that's how they assemble this part. Then this is closed, put under overpressure, and that's how it is brought out. So that's another step in the complexity to make sure that whatever we measure on Mars, is really from Mars. Now we know that there is some exchange of like meteorites. Mars rocks have been found on Antarctica. Yes. I believe people assume that it's possible the other way around as well. To a certain degree. Yeah. So is this the planetary protection like you just have been describing? Is that useful at all if you know that there can be exchange of rocks with what not on them? Yes. There are two answers to this question. First of all, yes it's true of course. We have meteorites from Mars on Earth. Yeah. And the process works the other way around because we have a deeper gravity valve here. It's not as efficient to go from Earth to Mars. But in principle the process could happen. Yeah. Now, the detail lies actually in the material that can be transferred. How does it work? You have a big impact, an asteroid impact on Mars that is energetic enough not only to punch a hole in the surface but also to eject material with enough velocity to go through the atmosphere to leave the gravity valve of Mars and to fly to Earth. Yeah. It is not clear that the type of material where we would expect life, sedimentary material, can survive such an ejection process. Solid material, rocky material, yes. And that's what we have found in the Martian meteorites. Yeah. But this type of materials that you also have on Earth and in the different places that is much more fragile. Very questionable that such material could survive the impact event and be ejected in a way that, you know, would still be able to leave Mars, fly to Earth and come here. Yeah. You would need a microbe that's inside that rock surviving first an impact event then being shut out and flying through space for a long time. Yeah. And then entering Mars' atmosphere or the other way around. Lots of heat will be involved in the impact. Lots of heat. Well, the time can be short. Okay. It is sometimes long. Six months. But it can be short. Yes. It can be a matter of years. Yeah. It can be a matter of much longer. Yeah. That is one aspect. I wouldn't necessarily stress it too much. No. The heating is true. You have heating when you eject the material on Mars and when you go through our atmosphere. But on Mars, when you eject something, there are... Actually, I'd rather discuss the other way around. Yes. You know, an impact on Earth. Yes. With stuff being transferred to Mars. It's the same thing. Yeah, of course. And then ask for energy. You need more energy. You need a bigger impact. Yeah. So, we have the same reasoning there. It's not clear that we can launch this kind of porous sedimentary material into outer space in a form that this material can actually survive, be transferred, and enters another atmosphere. Yeah. So, that's one answer. You have the landing as well. That's right. Yes. But that's one answer. And that's the answer of exchanging material. There's another answer, and that is protecting Earth. Mm-hmm. So, again, not clear that this happened actually in the past. But even independent of that, we can do it. So, we have to do it. Yeah. Because the public, but also regulatory authorities, deal differently with natural hazards and man-made hazards. So, even if this would be true, the level of scrutiny we would apply on a sample that we bring back with us from a specific location on Mars, on purpose, will be different compared to a natural influx. Yeah. It's like if you build your house in an earthquake region or fly on a plane or go on a train. The level that you as a person accept is different. And the same is true for regulatory agencies. The level of risk acceptance is different between man-made and natural phenomena. Yeah. I can imagine you must be the most detailed worker at ESA. Are you well-liked? Yes. Not as a person, but is your function well-liked? The planetary protection officer says no. Yeah, says no. Like, oh, we have to do it. No, no, no. That's actually... All of my colleagues work very hard. And most have much more knowledge than I about spacecraft, how it works and so on. I have one function. My colleague at NASA, Juxa, we have one function. It's a corporate function. But it's not there to make things... more difficult than necessary. So when we build a spacecraft, we have a big project on internal at ESA and with industry. Hundreds of people. And the project has a very high level of authority. The project manager representing the project. And it's very important because, you know, these things need to be delivered on time, on schedule. It's very complex. The thing needs to fly also. Well, and that's the thing. We all work with one goal. To get the thing to the launch pad, get it launched, have a spacecraft that works, and make sure that we have all our obligations covered. And with all our obligations, I mean our international obligations. The project manager or the project has quite some flexibility. And authority, I just mentioned before. And it's very important that they have that. There are, however, a few requirements that they don't own. Meaning they cannot change, they cannot ignore. And these requirements are related to safety and our international obligations. Safety, typical space debris, nuclear safety, and planet protection. Um... Where it's not only us that are responsible, but where we and our member states have international obligations that they have to meet. So these are actually covered then by agency level functions. And so in a sense, yes, we sometimes... We have to introduce these requirements. Um... We do it early enough with the projects. We make sure that the projects understand them and know why they are now there. And then we monitor it through the entire process of building a spacecraft. But it's not a policing function in a way that we try to police them and they try to cheat. No. That's not the way it works. I suppose your colleagues who are trying to design and build a satellite are aware of what you're trying to achieve. Yes. And they subscribe to it. Yes. And that's the thing. Training is exceptionally important in this respect for everything, but especially for something that is a little bit unusual. And that's why we have training courses, annual training courses, since more than 10 years now for the people at the agency, for industry, for... To get everybody aware of this kind of thing. Exactly. Thijs, I know we're nearing the end of the show. There's one very important thing that I still need to ask. No worries. No worries. How about human settlement? Yes. From a planetary protection point of view. That is a very important question. All in favor of that. Oh, yeah? Yes. I mean, we are discussing this since a couple of years now in dedicated workshops. Actually, the next one will be next month in Houston. It's not incompatible. Actually, it's very important. And I liked your example, the Kelly example you mentioned at the begin. Yeah. I think it's important. In order to have a safe human mission to Mars, for example, you need to understand how the human body reacts to the space environment and to the planetary environment. We have feedback from the Apollo astronaut. It was not that straightforward to go there, go in and out. The dust was a major problem. Yeah. Major problem. It's probably afterwards a little bit underestimated. Yeah. If we expose now humans, to a planetary environment like Mars, we have to deal exactly with, you know, hazards. Again, we have chemical hazards, we have physical hazards, and we might have biological hazards. So, planet protection in that sense is an enabling capability. We have to understand, is there a biological hazard for the astronauts? Because when we bring them back, we want to make sure that they don't jeopardize our environment here on Earth. Sure. And so, increased, increased studies of how humans adapt to the space environment, like the TWIN study, like more long duration studies, are extremely important. Because when we, the microbiome, for example, was measured for the TWINs. Very important to see how your microbiome, your microbiome changes when you expose to different situations. But how about, once again, the other way around? You're also supposed to, you're supposed to protect the environment on the planet itself. Yes, yes. To a certain degree. If Elon Musk goes, build his mission base on Mars. Well, next question will indeed be, does SpaceX have a planetary protection officer at all? They have now, yes. They have a person now that is responsible for planet protection. But let's stay with this question first. How can you protect the planetary environment against people who are teaming with microbes, whom you cannot clean or sterilize? Who are peeing outside when they need to go. Well, yeah. And that's, I think, a problem sometimes. Not to mention different activities. Sometimes in the science fiction movies, a mission to Mars is not a camping trip. No. There are a lot of reasons why we have to have a very close perimeter around the people. With that, I mean the habitat and the suit. Because of the limited resources we can bring with us, the suit cannot be very leaky, the habitat cannot be very leaky without compromising actually the safety of the people because they don't have enough resources. So everything has to be built in a very tight manner in any case to meet other needs. That's true. There is an aspect of bringing people in and out. Yeah. Which can be managed. They have to go through an airlock anyway. Which are going to have garbage. Yes, that you can condition. You can condition it with heat or with chemicals and you can close it in. The thing is, and that's why we discuss it now with the system designers of these flight systems for human missions, to make sure that we cover all the different aspects. When they manage the dust, which is carrying potential hazards, chemical hazards and potential biological hazards, they're covering our needs at the same time. Yeah. That's true. And when they think about maintenance of the suit, we have to weigh in on that. How do we condition the suit so that you can bring it in without problem? So that's why this communication in both ways is very important at that time now when you design these systems. But in principle, having a closed habitat and suit system with people on Mars is not contradicting necessarily planet protection rationale. We want to have people there because they're much more capable than our machines. But we have to make sure that they're there in a form that doesn't threaten them and doesn't threaten the science they want to do. And this, now after a couple of workshops with the science community and the engineers, I think we are on the right way to implement that. Right. And as you said, SpaceX is now also aware of this, the principles. Yes. And they're on board with this. They are aware. And again, there are other reasons why we cannot just have a very leaky environment there. It's just the nature of being in a very distant place. It's not the moon. We cannot have open systems like they had on the moon when you had the vapor cloud in the back of the EVA suit. It doesn't work on Mars because it's an atmosphere. You would have an ice pack in a minute that you could carry. So there are lots of reasons why this is actually easier than on the moon when on Mars. I just want to know, just to summarize, which planets or moons have you protected? In terms of missions? Yeah. Well, most of the work is going into the Mars business. And lately for Europa because of the new mission. For the future. Yeah. But it's being... The project is ongoing right now. And they're starting construction phase then I think later this year in Frutix. Exciting. Yeah. You're going to be there to protect Europa from us and the other way around. That's right. Thank you so much, Gerard. You're welcome. Thanks for having me. This was a great conversation. Yeah. It was. And Herbert, thanks to you as well. Just a quick note to our listeners about next week. Also, I'm very excited for that conversation as well. Because we're going to talk to Sarah Markoff. Oh yeah. She is professor at the University of Amsterdam. But not only that, she was also a member of the science team of the Event Horizon Telescope. Okay. The black hole picture. World famous now. The black hole picture. So next week we're going to talk about that picture and how it was made, what we will learn. What it means. Everything. That news was so big. It's like a cultural moment. Still ringing. Yeah. So looking forward to that. Thank you all for listening. Absolutely. Thank you, Gerard. Thank you, Herbert. Thank you, Thijs. And talk to you all next week. See you next time. Bye. Bye-bye.