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Marshall Po
Hello everybody, this is Marshall Po. I'm the founder and editor of the New Books Network and if you're listening to this, you know that the NBN is the largest academic podcast network in the world. We reach a worldwide audience of 2 million people. You may have a podcast or you may be thinking about starting a podcast. As you probably know, there are challenges basically of two kinds. One is technical. There are things you have to know in order to get your podcast produced and distributed. And the second is, and this is the biggest problem, you need to get an audience. Building an audience in podcasting is the hardest thing to do today. With this in mind, we at the NBM have started a service called NBM Productions. What we do is help you create a podcast, produce your podcast, distribute your podcast, and we host your podcast. Most importantly, what we do is we distribute your podcast to the NBN audience. We've done this many times with many academic podcasts and we would like to help you. If you would be interested in talking to us about how we can help you with your podcast, please contact us. Just go to the front page of the New Books Network and you will see a link to NBN Productions. Click that, fill out the form and we can talk. Welcome to the New Books Network.
Gregory McNiff
Welcome to the New Books Network. I'm your host Gregory McNiff and I'm excited to be joined by John Willis, the author of the Pale Blue Data Point, An Earth Based perspective on the search for alien life. John Willis is a professor in the Department of Physics and Astronomy at the University of Victoria. As an astronomer, he studies the physical contents of the universe and his research covers many aspects of cosmology and astrophysics. He is particularly interested in giant clusters of galaxies, both for what they can tell us about the large scale properties of the universe and the astrophysics of galaxy evolution. I selected the pale blue data point because it turns the search for alien life into something concrete by grounding it in the field work here on Earth. John blends planetary science, geology and biology, and I should say also history, in a way that is vivid, rigorous and accessible. His approach sharpens how we think about the evidence, the uncertainty and our discoveries and what it would realistically take to identify life beyond Earth. John, thank you for joining us today.
John Willis
It's a pleasure. Thanks for having me, Greg.
Gregory McNiff
John, why did you write the paleblue data point and who is the target reader?
John Willis
Okay, so why did I write it? Well, I have to take you in a time machine back about nine years and I just finished my first book, which is kind of a regular astrobiology book called all these Worlds are Yours. And I was really pleased with it. But I realized there are some things it hadn't done. And the thing it hadn't done is it hadn't really answered the question, what does an astrobiologist actually do? Right. I'd written before about what the science of astrobiology is, but not what it looks like on a day to day level. And so I still remember about nine years ago, I sat down with all the freedom of having that brain space. I've just submitted a book, right? You've got all that brain space after a big project. And so I put down the spider diagram of all the ideas I could think of that would answer that question. And that was basically my plan for the next nine years. That was my life, right? Is going out, joining these groups, learning from them in the field, and I think very much so as well, trying to celebrate their science and their work. Right. So that's why I wrote the book. Who's it for? Well, I guess I've given a lot of talks and presentations on this over the last more than nine years, ten years more. Right. As I've been working with this material and it's very much speaking to those audiences, right? So that means public talks, that means observatory nights, that means science fairs. You meet such an interesting range of people that have one thing in common. They think this is cool. That's the price of the ticket to get through the door, nothing else. Right. And I really enjoy at the moment, right. So I'm teaching an undergraduate course in astrobiology at the moment. It's one I've taught for a number of years. The only prerequisite for it is you need to be a second year student or higher at the University of Victoria. And so I get such a range of bright, interested kids from all kinds of backgrounds, all kinds of experience, not just the ones you might think of, say biology or geology or geography, but I've got computer scientists, I've got philosophers, right. And, you know, know it's a really healthy environment in which to discuss ideas. And so it's all of those people together is who I'm speaking to when I write the book.
Gregory McNiff
Makes perfect sense. John, I have to ask, given, you know, you obviously look like a young guy, but you've been teaching for a while. This is sort of a lead into my next question where you ask about, we're rapidly approaching, I should say where I ask you about rapidly approaching first contact with alien life. But just to follow up on your opening response there, have you noticed an increase in the level of interest or the intensity, whether from your students or the public, about what astrobiologists do and the search for extraterrestrial life over the last five, 10 years, maybe with James Webb coming online. Is this something that's been sort of a common theme since you began teaching, or do you think there's been an increasing public awareness to this search?
John Willis
No, that's a great question. I mean, I think there's always been awareness and interested in the question, right. What I have noticed is folks are much better informed, right? They're really following what's on the science news. And for example, I would always have a moment in one presentation. I'd show a graphic of all the moons of the solar system and then planet Earth on there as well. And I would ask the audience, where do you think most of the liquid water is in this image? And of course, 10 years ago, 15 years ago, everybody was kind of drawn to that. Well, the pale blue dot, right? Planet Earth. But now more and more people know the trick, right? They put their hands up straight away and they say Europa, right? And so there's a real appetite for, well, I don't want to blow my own trumpet too much, right? But for something a bit meaty, not just where you get into the details, but you get into, why are we doing this? Am I in a position to be able to tell you this is going to work or is this our best shot? There's a kind of an intellectual honesty that I've learned from the audiences as well, especially with under. Well, not so much with undergraduates. I do a lot of school presentations. You cannot fool a middle school kid, right?
Gregory McNiff
No, absolutely not.
John Willis
If they're interested in what you're talking about and if they've got some background in following this. Right. They are going to be a very well informed and critical audience, let me put it that way. And I like that because as a scientist. Right. Keeps you honest.
Gregory McNiff
Yeah, yeah, that's interesting. It's almost like it's a conversation or an interactive dialogue with you and the public. I mean, obviously you spend a fair amount of time talking about Carl Sagan's influence. Candidly, the title of your book. Right. I should say Data, point, verse, dot. But yeah, but yeah, you're right. I mean, you obviously are a public speaker on this. There's a few other high prominent ones as well. But it does seem like the public, through the news, and maybe it's specific periodical, Scientific America, new scientists, astronomy journals, local astronomy clubs, but it seems like they're really. And maybe I just attribute it to James Webb, that seemed like it got a lot of attention and then obviously Vera Rubin came online a few months ago. But it does seem like, and I don't know, maybe it has to do with private, the SpaceX race as well. But it does seem like the public's attention is really fascinated with this. And I want to dive in because you actually hit on a number of questions. And I should say I always tell my readers, you know, on the equation side, there really is only one equation in here. And we're definitely going to talk about that. But John does a great job of literally walking you through each of the variables and giving you the conceptual background for why that equation is what it is. And candidly, that's really an equation you should know. John, you say astrobiology is rapidly approaching first contact with alien life in the opening of your book. Why do you think that in writing.
John Willis
The book, in having these experiences, working with these people, it's impossible not to feel the energy, right. The effort there is. And you know, it's. And we've kind of gone through. We're very fortunate to. You know, we always say this in science, right. We only see so far because we sit on the shoulders of giants, Right. You know, when you look back, for example, at some of the real places we're exploring at the moment, Mars, the moons of Jupiter, the moons of Saturn, right. The space missions we've got coming up, right? We're going to the right places, right? We're asking the right questions. Does that mean we're going to find life in the next 10 years, the next 30 years? You know, I'm very reticent to tell people yes or no because I can say what we're doing is really plausible and smart, right? I just don't know how lucky we're going to be. You know, is there going to be some weird chemical signature on a liquid ethane pond on the surface of Titan when Dragonfly gets there and flies up to it? The new space mission to Saturn's moon Titan, I should say. And even when you look at some of the great stories, even this fall, that have come out from the Perseverance rover at NASA, looking at rocks that are showing hints, it's the best word I can use. Hints of possible ancient biological activity. Fossils, if you like, that could be life, could be many other things, right? There's a lot of, you know, confusion even with Earth's oldest fossils. That's the whole reason why I go to Western Australia to teach people, you know, about, first of all, what do these fossils look like? But what are the ambiguities, right? These aren't smoking guns. So, you know, that's why, you know, it's themes like that, right? Like the energy, like going to the right places, like starting to get these first hints that tells us it feels like, you know, work is happening, effort is being expended in the right places. Does that mean we're 10 years from a detection? I have no idea. Absolutely no idea. And I'm totally honest about that. All you can do is keep plugging away. And in some ways, that's why it's really interesting to, you know, write about astrobiology, to participate in it, because it's a young science, right? It's been called before a subject in search of subject matter, right? It's still heading there for its first detection. And, you know, one theme of the book is a lot of the people with whom I've worked are quite reluctant to call themselves astrobiologists. It's almost as if, well, the entry ticket to the astrobiology club is, well, you've got to find alien life, right? And so people are being quite, you know, reticent and careful, but, you know, what they're doing is astrobiologically relevant. I do, actually, when I, with a number of audiences I work with, I'll ask them, when do you think we're going to discover alien life? And we have a poll and I ask them, is it going to be 10 years? Is it going to be a hundred years? Is it going to be a thousand years? Right? And there's kind of a bell curve, right? There's a few people put their hands up for 10, few people for 1,000, but most for 100. And I tell them 100 is a really interesting number because it says, well, we might detect alien life if we make the right choices. Now. Oh, that's interesting, right, because, you know, I really tell them that there's a, you know, if you want to get people excited about a space mission, say to Enceladus, fund it, build it, fly it, and interpret the scientific results, you're looking at 40 years, right? That's that, that's what, 30 to 40 years. That's what it's going to take from sort of first light bulb moment to write the last line of your scientific paper. And sometimes that's a little bit of an eyebrow raise moment to think, wow, that long. But I tell them if you make those smart decisions now or if your forebears have, say 10, 15 years ago by starting a project that you become associated with that 100 year timescale, that's realistic.
Gregory McNiff
And John, presumably 40 years and tens of billions, I think James Webb was, the price ticket was like 8 billion. So I can't even imagine what the next mission would cost. But it's that kind of thing, right? Like seating the government. I mean, you're, you're working on a number of fronts, right? The funding, the public, the public awareness and support for it. And then obviously the logistics. I mean, I just can't even begin to imagine how many people would be involved in, you know, working on a project like that.
John Willis
Oh yeah, and that was one of the privileges of the book is being able to meet these people who are really on the front line, right. Some of the Mars Rover teams that are operating things like perseverance and curiosity. And one thing that really struck me as well, right, is how young, bright and capable they all are, right? There's a few old white dudes in the room, right, who are kind of keeping the field trip on track, right? But there's so many bright young people. Now when I say bright young people, right, okay. They've still got a bachelor's degree in science, they've probably all got a master's degree, and a fair few have got PhDs as well. But these are people under 30 and they're the ones in the room who are actively debating the science Are we going to do this rock? Well, if we do this rock, that's going to take us away from this big valley that we've been planning to get to. Right. And to me, I possibly geek out on this a little bit too much, but that is the nuts and bolts of science, or if you want the baking analogy, that's when you're really getting the ingredients and mixing them together and waiting for the magic to happen. Right. And I love that. And so it's really. I hope the book carries with it a sense of fun. But it was so much fun, right, working with these people?
Gregory McNiff
Oh, yeah. I mean, it sounded like it. We'll get into it. But I mean, you're going to the depths of the ocean, you know, the desert, obviously. I mean, at one point I think you're swimming with dolphins or at least spending time with them. So, yeah, totally. I don't want to. I think you actually say it's not scientific tourism at one point, but it. I want to get to the thesis of the book. But before that, I do want to ask you, we will spend some time on the Drake Equation, but you must get asked about the Fermi Paradox, Right?
John Willis
Oh, where are they?
Gregory McNiff
Yeah, where are they? Yeah, I mean, I know that's not an explicit thesis in your book, but where are they?
John Willis
Well, now, the Fermi paradox is often applied to intelligent life, but even if you think about where is all the basic life? Right. This is why there's some interesting stories, actually, is nobody knew, for example, about microscopic life on Earth until Antonie van Leeuwenhoek was the inventor of the microscope, you know, gave us the ability to see it on that level. And so as humans on Earth when we didn't even know about the microbes living up our noses, Right. It tells you it takes a little bit more than going to say the subsurface ice of Mars or these amazing, you know, liquid ethane and methane environments on Titan. Even though it's amazing to go there, it's going to take some really rather specific tests to answer that question. Unambiguously. That's a really important word. So that's to say, one answer to the Fermi paradox is it's out there. We just need to go and look properly. Now with intelligent life, very different debate, Right. But the question is, and something I do discuss a little bit, well, what counts as a visible signal? Now, the problem is we think like humans pretending to be aliens, Right? But I think one example I use in the book is what if it's a lighthouse that switches on every 10,000 years to an alien, that could be an unmistakable signal on the timescale that they're interested in to humans. Okay, maybe we're 9,000 years away from the next flash. Maybe not. Maybe it was recorded in a Chinese astronomical text a thousand years ago, and we thought it would. So what, you know, if there really is alien intelligence out there trying to contact us. Right. You know, I think, you know, working out what that means. Right. What that might look like. It's a completely open parameter space. Right. And we are often approaching this, you know, from a very human perspective. If you go all the way back to the initial ideas. Right. Let's look for, you know, 1.42 GHz radio emission, because that's close to the 21 centimeter hydrogen line, and that offers a practical route to sending a clear signal. That's a good, practical decision. But does that mean things are broadcasting on that frequency? Absolutely not. There's no real reason. It's the best guess that lets us get going. Right. So, I mean, I talked about a couple of things, though, to cycle back. The Fermi paradox is a little bit arrogant, right? In the sense that it assumes we'd know what we were looking at.
Gregory McNiff
You nailed my next question. It is, what is life as we define it? I mean, you cited the inventor of the microscope, Anthony Bent, Lande Hook, and he actually, or I think you say from there we progressed to microbiology. And you talk about the central role of DNA as an evolutionary molecule as well as ATP. Is that how you would define life, like DNA, multicellular ATP? What are we looking for?
John Willis
Well, these are the defining building blocks of Earth life. Right. And it's one of the incredible things that you learn from the pale blue data point is that at a fundamental level on Earth, we are really all the same. And when you take. Well, wait a minute, if we're all the same now and we're all the products of cell division, what does that mean we started from. And that's a great way of going back into the past and working out maybe what early life on Earth looked like, trying to learn from that. What are the universals of life that you could use to recognize alien life? Well, then you've got to be a bit more careful. And so one way you can approach is, and I do this in the book, a bit more like a physicist, right? And that's ask the question, not what life is, but what does life do? A slightly different approach. And so what life does is, well, it orders itself into these Tiny structures we call cells, it metabolizes, which is basically a reaction that benefits from sort of the flow of energy through a system. The analogy I use is it's like the wind on the sail, right? The passage of electron is like the flow of energy through any system of chemicals, molecules. Right. And life has worked out how to nibble little bits of energy from that to make its own processes work. So that's metabolism and then evolution. Well, you could say that's actually an extension of order, but it's order on the basic level of chemical building blocks. C, A, G and T nucleotides, amino acids, sugars, this kind of thing. And so could we learn to recognize chemical signatures that just don't fit right. In a particular environment or that might be. They're a little bit more complicated than you would expect just from random interactions alone. Right. So these are quite subtle points. But, you know, let me put it another way. A good approach for a basic first space mission to a moon like Europa, Enceladus or Titan is just to work out what does the chemical background look like, what chemicals are there? Right. Can we explain them using the conditions that we see there? The temperature, the pressure mix of raw materials? And then you ask the question, as you explore a bit more, do you see anything that looks weird, anything that doesn't fit there? Right. For example, you might find a pond where instead of the usual chemicals, say 2, 3, 4, 5 carbon atoms, there's one particular pond where there's systems of 30 carbon atom molecules, right? And 40 and 50. And you think, wait a minute, what's producing those big molecules that can actually be quite fragile and would be normally broken apart? And so then you zoom in there and maybe that's your first clue. Is there a metabolism there? Is there a cyclic reaction that's building up that complexity? Because the other thing, you know, when we really get to the fundamentals of life, and it's a wonderful question that doesn't have a clear answer. When does chemistry become biology? What is that point? Right. And I tell the people I present to, the students I teach, don't expect it to be a finely drawn line. Could well be a fuzzy boundary, right? And you've got to spend. And so essentially the way to answer it is to spend time investigating interesting environments at that level in situ. Perfect.
Gregory McNiff
As usual. Your answers are catalyst for more questions. John, in terms of chemicals, obviously oxygen and methane would be clear signatures of what others do you think, do you think might indicate life? And then you mentioned metabolism at one point in the Book. I think you paraphrase Descartes. I metabolized, therefore I am. Is that what you would say? You raised such a fascinating point about the transition from chemistry to biology. But that metabolized, therefore I am. If we find something that metabolizes, have we found life on an exoplanet?
John Willis
The pause is me hedging, right? The simple answer is yes and no. So one thing I do is right. Let's say you take those three ideas. Order, metabolism and evolution, okay? Because. Or you could say reproduction, right? Because if you have flawed reproduction, you will get evolution, right? So if you reproduce your little tiny bug, but with a few copying errors, then the next generation will be a little bit different. What I do is I say, well, on Earth, those seem to be the three fundamental things we do, right? So why not score each one of them at 33%? Just like when you're doing a university course, you get told, okay, your midterm is going to be 20%. Your final exam's going to be 50%. Your labs count this much, let's give 33 and a third percent to each of metabolism, order and flawed reproduction. Okay, now what does that mean? Well, if you see something that gets all three scores 100%, that's great, right? If you get just metabolism, well, you've only got 33%. Is that a passing grade? Right. And we just don't know enough about that fuzzy transition. I sometimes try and be provocative. I call it the genesis point, right? Where chemistry transforms into biology. Biology emerges from chemistry, okay? But what I would say is, in the past, we have seen that metabolism test applied as the sole test of life. It's the basis of the biology experiments on the Viking mission to Mars in 1976. All of the tests that were applied there were essentially metabolic in origin, right? Looking for one chemical being processed into another and a waste product being produced. So it certainly has been applied, but it also has the limitations as well. Is there a non living chemical reaction that could produce the same result?
Gregory McNiff
Perfect.
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John Willis
And breathe.
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Gregory McNiff
And John, I just want to set the thesis of the book is obviously we're, you know, looking for particular biosignatures of the formation of life on earth would provide a lab for what we might find on these exoplanets. And I want to drill into that. But just to set the stage. You make the insight or the. You continually reinforce this idea that every star has a planet attached to it. Or roughly it's one to one throughout the book. It's a common theme. And then I'm just going to read you. I'm going to read you your book, John, on how big the opportunity is. Because at some point I do want to talk about the Drake equation. And one factor is just what we call in finance the Tam. But how many planets are out there? You write hundreds of billions of galaxies, each populated with hundreds of billions of stars might well mean that we exist in a universe populated by a number of planets that's written down as the number one, followed by 22 zeros. Though we can calculate that number, it obviously stubbornly defies our comprehension and we risk losing our place in the universe. Is it fair to say there are, you know, beyond trillions of potential exoplanets, planets that could exhibit signatures of life?
John Willis
That's two points there. Is it true that there's, you know, potentially, you know, a vast. Let's define a vast number of planets right out there. Exoplanets. Absolutely right. That's the whole point in things like the Kepler mission, the TESS missions, to work out not so much what planets are there, but what does that represent statistically, when we extrapolate to all the stars we've not been able to study in the same level of detail. So vast numbers of planets, absolutely solid. Tick. Right. That's 30 years of wonderful research has meant we've gone from not knowing any planets at all to. To really knowing that number now. Potential habitats for life. Yeah. Each planet is a potential habitat for life. Right. You know, because if you're going to be completely broad, you know, talk about maybe, you know, all weird kinds of life that I can't rule out, but I have to sort of, you know, give a nod to. Absolutely. But then it comes down to the practical question. Let's take that number. Right? One, followed by. What did I say, 22 zeros. Right. How are you going to pick five and actually ask that question in detail? That's what astronomers are dealing with at the moment. Okay. Which are the ones that we think offer not just the best chance in terms of, oh, this is the most likely habitat. But what is practical, given the sizes of telescopes we have at the moment, given the kinds of techniques we have for studying the light from the planet when it's outshone by its parent star anywhere from 10 million times to 10 billion times. So there's always this marriage between the kind of planets you would like to look at and the kind of planets you're capable of looking at. Almost like that kind of Venn diagram overlap. And that overlap's not very big at the moment. It's certainly not one followed by 22 zeros.
Gregory McNiff
Totally. And when talking about life, maybe you quote, it might be Sagan, but somebody who says, I'll know it when I see it. What type of exoplanets would we like to look at, I mentioned oxygen and methane. You give a few other criteria. If you could list the criteria for the exoplanets, what would number one be? What would it have to have?
John Willis
You know what, if you want the truth, I give this answer to my undergraduates. I think we were talking about exactly this week the idea of exoplanet spectroscopy to be able to talk about what's going on in their atmospheres. And I told them, I said, in terms of biosignatures, can I come back when we've looked at the first thousand and tell you. Yeah, because nature has to teach us the rules of planetary atmospheres. How many do we have at the moment? We've got Earth, we've got Venus, we've got Mars and we've got Titan. Right. Well, you could also put in the gas giants as well, but let's maybe keep them separate. Let's keep Jupiter, Saturn, Uranus, Neptune. Let's keep them separate for the moment. So we've looked at essentially at 4 atmospheres around Rocky icy bodies in detail. I don't think that's enough. And so if, and it sounds like I'm telling you to come back a thousand years, not quite, but because nature will tell us from, let's say, for example, those first thousand, what chemicals do you see all the time? What's really common? What physical processes are going on in these atmospheres that make these chemicals really common? And then in a thousand, well, you stand the chance of finding say ten examples of the one in a hundred planets that show something a bit weird. Now, I don't quite know what that fraction is. Is it one in a hundred, Is it one in a thousand? Where you see. Now I don't know if it's going to be oxygen or methane, but let's pick it as an example. Let's say you see a planet where methane is really out of whack compared to where you see it with the other planets. Its temperature is the same, its gravity is the same, it's round, similar types of stars, but it's got a methane signature that's completely different. Right. Well that's nature teaching us and that's why discovery driven science is so interesting because it doesn't matter what your preconception is. Right. Nature's going to tell you how things work and your job as a discovery scientist is to respect that process. Right. So I'd love to be able to speculate for you and say, oh, it's going to be methane, it's going to be oxygen, maybe it's going to be phosphine, right, as people have claimed on Venus. I just don't know. And so as a discovery scientist, I have to take the patient approach and saying, well, just give me a thousand planets, that's all I need. Just give me a thousand atmospheres and then we'll give you a much better answer.
Gregory McNiff
Great answer. I'm going to push back a little. Is finding the biosignatures just the first step? And here I'm going to reference the Gaia hypothesis of James Lovelock, who argues that Earth's biological inhabitants are linked by a multitude of chemical reactions to our planet's atmosphere, oceans exterior across molten interior. In this great connected system, every terrestrial molecule is in chemical balance with every other in a finely tuned planetary equilibrium. So just finding the signatures, that's not, we're not done, right? I mean we're almost looking for an equivalent ecosystem, finely tuned equilibrium, something more. I mean, I think at one point you talk about the levels of oxygen and methane that the Galileo probe found on, I believe it was going through, I think it was Mars and it was a very high abundance.
John Willis
That was just to correct you there, Greg, that was Earth, right? When Galileo flew by Earth, that was Carl Sagan answering this question, right, what is life? I'll know it when I see it. And so his response is, all right, what do you see when you fly this Jupiter space probe past Earth? And that's where we got that idea of biosignatures from.
Gregory McNiff
Got it. So I may edit this. John, my question to you is basically beyond biosignatures, we should also be looking for ecosystems or finely tuned equilibrium planetary systems. How do you think about that?
John Willis
Always my answers are going to be rooted in terms of what's practical or what might be practically possible to achieve in say, the lifetime of the people reading the book. Right. So we've talked about being able to get a spectrum of an exoplanet's atmosphere and learn something about the via things. You've talked about the Gaia hypothesis, the idea that biology is part of the physical makeup of some planets or certainly on our planet and we can recognize that from chemicals we see in the atmosphere. What else could we do? Because you talked about trying to find an ecosystem. Well, let's imagine we detect a biosignature around an exoplanet from spectroscopy of its atmosphere. Clearly we're then going to study that in much more detail and you might see other chemicals that are part of that overall planetary system that have something to do with biology. So you'll be able to talk about the ecosystem from the different chemical elements you're seeing and the different molecules, et cetera, what role they might be playing. Depending upon the properties of the planet, you could image it directly, right? And actually ask the question, all right, what are we looking at here? Is it a pale blue dot, Is it a pale green dot? Is it a pale red dot that still might be something like chlorophyll? Because that pale red dot is actually going around a dim red star. And if you were going to make use of those kinds of stellar photons for photosynthesis, you'd have a slightly different light capturing molecule. Right? So you can. Those are the kinds of questions that to me at least seem accessible given the kind of technology that we are starting to develop right now. And it's going to come to maturity next decade, next two, three, four decades, it's going to become more commonplace. And I really kind of think it's useful to think about this idea of when are we going to reach our thousandth planet exoplanet atmosphere? By the time we get to that point, we're going to be having a very different conversation about the kind of things that look like the kind of chemicals that appear to be common. And though, you know, by that time we'll probably have three or four weirdos that we, that, you know, we talked about, you know, all these chemical interactions that link, you know, the geological properties of the planet to the oceans, to the atmosphere. And then do we throw biology into the mix? We'll have a few planets out of those thousand where it won't add up. If you just take geology and chemistry of the oceans and maybe other things, you won't be able to explain some of the chemistry going on there. And the question then will be, is, is that life or is that us learning something about planet atmospheres, that they work in ways that our few examples we have in our solar system don't reproduce? I just think that's a safer, more mature answer than saying, oh yeah, you've just got to look for abundant oxygen. You find abundant oxygen, you're going to be fine. Because that's a bit of a lazy answer because it might be some chemical that on Earth isn't actually used in our life recipe. But I can't rule out that there'll be an exoplanet where that chemical is part of some life recipe and that's the chemical that's going to be out of whack.
Gregory McNiff
That's interesting because you have a section in your book where you're talking about the meteorite ALH84001, and you reference Bernard Bloomberg, not only a Nobel Prize winner, but the head of NASA's astrobiology, who suggests the. I think he's counseling David McKay. They focus less on a searching, the search for a smoking gun, and more on, quote, converging lines of evidence that suggests, you know, the mere chemistry was occurring. He's talking about why it's on this planet. But it seems like you're also suggesting, hey, look for an incremental approach to signatures of life versus specific smoking gun. Because we don't know exactly what we're looking for, but slowly accumulate the evidence. I mean, is that kind of where you're going, sort of an incremental approach as looking for one specific thing?
John Willis
It's not necessarily the way I'm going or advocate going, but it's more counseling people you just might not be lucky enough to get a smoking gun.
Gregory McNiff
Yeah. Okay.
John Willis
Right now we're looking at these signatures. We're talking about signatures viewed at great distance. What do I mean by distance? Well, ALH84001, you're looking for potential biosignatures that are about 4 billion years old, maybe a little bit less than 4 billion. But that's how old the rock is. Right. That's rather a long time ago in the past. Right. That's why it's useful to look at. Well, what can we tell from Earth rocks that are three and a half billion years old? Turns out that cutting edge science there is quite contentious and heavily debated. There's a lot of academic to and fro, which is entirely correct. That's entirely what the cutting edge should look like. Right. With exoplanets. If the exoplanet was in our own solar system, when we could study it in immense detail, we wouldn't be having these kinds of conversations. It would be all very obvious. Right. But they're light years away and they're right next to their parent stars. And so we have to fight against the glare of these stellar photons. And that makes it difficult to get the kind of answers you'd really want to give you a smoking gun. So we actually have to put this jigsaw puzzle together. Right. Not quite with one hand tied behind our backs. Right. But we're not given all the pieces we want. And yet you still have to work out what the picture is.
Gregory McNiff
Yeah, maybe with a dose of humility and just keep moving forward. John, I do want to come back to this quote. You say astrobiology is rapidly approaching first Contact with alien life. Why rapidly. Why do you say that?
John Willis
Oh yeah, it's just the energy right now. And let me say this, just because I write it in the book don't mean I'm right, okay? You've got to be self aware enough there, right? The reason I feel confident in saying it is because let's take the example of the solar system. I think we've done enough, let's call it reconnaissance of the solar system to work out not where the best place is, not where the worst is, but where we've got a plausible top three or top five. I think we've got a really plausible top rank of candidates now and we're starting to go to them in an interesting level of detail, right. For example, Mars. Where's my top thing that gets my astrobiologically antennae wafting on Mars? It's these so called recurring slope Linux. It looks like seasonal melting of subsurface Moncton ice that's coming out where you have big rock outcrops just like you do when you go and see the mountains on Earth now. Very interesting in terms of it looks like there's seasonal flows of salty water and who knows what else. But I tell the students and also readers and people at my public talks, it's the worst kind of terrain for a rover. But isn't it amazing that just in the last few years we've seen a drone fly on Mars, right? And so clearly it's a really lightweight prototype. But if you're ever going to get to these recurring slope linnae and sample some of that perhaps liquid salty water in situ, it's going to be with a drone flight, right? And so we've actually got the right elements there, right? Or if you take, you know, Titan is just ridiculous, right? It has an atmosphere, it has bodies of liquid, it has not oceans as such, but you know, lakes, this kind of thing, all with these interesting, you know, chemicals that are, you know, reminiscent we think of early Earth before life formed, right? And we're going there with a car sized drone. Now I can't guarantee what's going to happen and let me be careful, right? You know, the experiments on the Dragonfly drone going to Titan, you know, are designed to characterize the chemical environment, get the background right, and look for weird things that don't fit, okay? But when I say we're rapidly approaching that moment of first contact, I look at these kinds of missions and think to myself, I wouldn't be doing anything differently. These people are going to the right places with the right kind of technology. And also the thing I really like about these slightly smaller, more dynamic missions is you can start to bring in new technology. Right when I mean, I still remember when the Huygens probe landed on Titan and the mission engineer, one of the mission engineers said it was like landing on Creme Brulee. Right. In that you crash through the crust and you sink it in some sludge beneath. And I was astounded by just a few photos we saw from the surface. I could never have imagined that 20 years later. Right. 20, 25 and beyond, we're going to be going back with a nuclear powered drone.
Gregory McNiff
I keep opening up more lines of questions here. I want to briefly talk about Mars, but before that you mentioned the drone. In the book you talk about being excited about the European. I'm sorry, the Europa Clipper and Reason, an acronym for the Radar for Europa Assessment and Sounding Ocean Linear Surface. Why are you excited about them? And particularly as it comes to looking under the Europa and ice sheet.
John Willis
Oh, right. Well, to put it into context for people. Right. Europa is a moon of Jupiter and it's slightly smaller than our moon. Right. Our moon is. Oh, it's got a radius of about 1700 kilometers. I apologize for the unit. I think in meters and kilometers. Europa's a little bit smaller. 1500. Right. But you have to imagine underneath that ice sheet there is an ocean 100 km deep that goes around the moon. Just an incredible place. We think the water is salty, we think it's in contact with the rock, we think it's heated by lunar heat that's coming out because of this incredible gravitational interaction with Jupiter. An amazing environment trapped under somewhere between 10 and 30 kilometers of ice. We don't even know how thick the ice sheet is. Right. So reason on Europa Clipper is first of all it's going to tell us how thick the ice is. Incredibly important to know this. Right. But also, and we see this using the same technology to map the Antarctic ice sheet, it's going to tell us about the 3D structure of the ice sheet. Is it a big solid block or is it more like. I use this word, cryogeology. Does it show the same kind of things in terms of ice dynamics that we see, for example on Earth with our mantle dynamics, do we see convection of ice over long time scales like mantle plumes? Right. Does that mean that ice can be in contact with the ocean and then maybe 10,000 years later it's cycled up to the surface? Well, that's important because that's then a conveyor Belt. That tells you that you can make some measurements of the ice sheet at the surface of Europa and learn about the chemistry of the ice ocean interface, right? Because getting through that ice sheet, I don't like to use the word mission impossible, but it's mission very, very difficult. But if reason is able to look at the ice sheet and tell us about it's actually got internal dynamics, there's weak spots, there's upwellings. That's going to be really important because it means by studying the ice, you can learn about the ocean.
Gregory McNiff
I'm curious, John, do you think our studying or looking for extraterrestrial life is giving us a better understanding of Earth? I mean, you talk about our theory of the oceans becoming the theory of the planet itself with plate tectonics. I feel like we're still learning about Earth. I say that at a high level, but how we're structured, how the planet was formed, whatever, 4 billion or so years ago, how do you think about that? Is that an interactive relationship, looking for life on other planets gives us a better understanding of our own planet?
John Willis
I can only speak from my personal perspective, right? And that's what I try and give in the book. Because people are so different, so varied in how they approach new knowledge, whether they accept it, whether they don't accept it, this kind of thing. For me, it's all about learning these wonderful connections, right? Sometimes I have to give myself a little slap or a nudge just to break out of these reveries. Because if you go out on a sunny spring day, right, all I'm seeing are cascades of solar photons that are being transformed by chlorophyll into electrons. And I see all these free electrons flowing through the living surfaces making eventually this thing that we are, right? If you stretch out those connections, there's a few in the book that I found really penetrating, right? The fact that we're even seeing it this week with Comet 3i Atlas, right? This amazing interstellar, completely natural, non alien made visitor, right? That means we can now study these lumps of rock and ice flying through our solar system. And it tells us about the chemistry now of some random exoplanetary system maybe, you know, light years away, that we are all connected, right? There are these deep connections now, they're not always fluctuating on human timescales. The timescale of a cell is a few seconds to a few minutes. The timescale of an interstellar comet crossing the void might be a quarter of a million years, okay? But we can all order it and put it into this context. That, to me, is what I find. It's an oft said phrase. Let me put it this. We are part of something larger. It's very difficult to be constantly aware of it. But what I did find as well, at a few moments when I was out at some of these spots I was fortunate enough to visit on planet Earth, you do get that sense of connection. And that was something I really wanted to share.
Gregory McNiff
Yeah. No, it definitely comes across. Yeah, you nailed it. Earth is part of something larger. We're not an island. I guess, to paraphrase John Donne, you mentioned Mars earlier. I do want to hit on some of the, I say case studies, but places you visited. One particular was Western Australia, which has some of the oldest evidence for life on Earth. What you know, how do you view these fossil structures, stromatolites formations in Western Australia? How are they valuable analogs for searching for biosignatures on Mars?
John Willis
Oh, yeah. I'm actually doing my book launch on Wednesday, and I've got a wonderful image where I've got, you know, living stromatolites in Western Australia that you can go and visit today. And I've got a picture of Mars today with the Perseverance Drone. With the Perseverance Rover Ingenuity drone side by side. And that's Planet Earth and planet Mars today. What's amazing is I can go about, oh, I think, two, 300 kilometers away from those living stromatolites today in Western Australia, and I can see almost exactly the same structures preserved in rocks 3.5 billion years old. Okay. And, you know, there's a long history of the study of those. Now, when you get to the very oldest ones, there are open questions. It's not a done deal. And it wouldn't be half as interesting as it is if it was a done deal. Right. But I can trace a lineage from those living stromatolites today back to three and a half billion years ago and remember Earth three and a half billion years ago. The sky was orange, the ocean was green. Right. It was an alien world. However, when I go then to that picture of Mars today and go to what we've learned about what Mars was like 3.5 billion years ago. The bottom line is we see evidence of widespread stable liquid water on the surface of Mars. The only way we could get that is if there was an atmosphere that was warmer and wetter than exists today. Much warmer and wetter. Right. We know what produced it. There was these vast volcanoes on Mars that we can see evidence of, you know, dormant and extinct volcanoes today. So then you ask a really interesting question. If on Earth three and a half billion years ago, I can go out and I can actually reach out and touch the fossils of these stromatolites that were the living creatures in that epoch. But if Mars was basically the same kind of physical environment three and a half billion years ago, what was going on there? How would we recognize it? Well, by going to Mars and looking, it's a very simplistic way of putting it, but looking for stromatolites on Mars or looking for evidence of the same sorts of physical evidence we see in rocks of that age on Earth, try and do the same tests right now. It sounds a bit like a no brainer and overly simplistic, but that is basically the reason why you go to Mars and you want to bring bits of Mars rock back from that exact period. If you look at where the Perseverance rover landed, it's on an ancient river delta, right? Where sediments have flowed down in a liquid water environment and been preserved as sedimentary rocks. When we study those same kinds of things on Earth that are preserved from three and a half billion years ago, that's where we're finding the stromatolite fossils you talk about.
Gregory McNiff
A Mars sample return mission would mark a generational moment in the exploration of our solar system. But you also say it's proving harder and longer than I guess we originally thought. We've talked about government funding and public support. What else is needed to bring back samples from Mars?
John Willis
Will. It's all about willpower. Because if this is something you want to make happen now, one of the basic reasons why it's tough is because let's say you go to Mars with a perseverance rover that costs, let's call it one unit of cash, right, for planetary exploration. And ballpark people may pick me up on the exact number I'm going to give. But let's take a ballpark figure of, say, four to five billion dollars right now. That's pretty much what it costs to do any one of these kinds of flagship missions into the solar system. Dragonfly is going to be a little bit cheaper to Titan, I think, but it's of the order of that amount of cash. Doing a sample return mission on Mars before it was postponed a couple of years ago was getting up to about $12 billion, right? That was the projected cost. And the concern was that cost wasn't quite under control. So that's becoming two to three units of planetary exploration cash and the big problem in the community was how do you persuade somebody who studies, say, Enceladus or Titan or even Europa to give up on their science? Right. So that you then let's say let's just go to Mars and just bring those rocks back. Because that's what was happening. It was going to. Going to Mars and bringing rocks back was going to stop us doing a lot of other things. And there wasn't that cohesion in the community of being able to say, this is a comprehensive plan, we get behind. Right. And so that doesn't at all take away from the fact it is incredibly interesting to do Mars sample return. Right. But either there needs to be more money or you need to partner up. And they've been trying to do this with the European Space Agency, perhaps a little bit broader as well. But it's a really tough human call because I've talked to researchers who study Titan, Enceladus, this kind of thing, and they don't want to just give up on their science for the rest of their life. That's the rest of their career. And so it's trying to find a plan that the community can get behind and then exercise the willpower to say, this is going to happen. This is our top priority. Make it so. Right. That doesn't mean you get the funding, it doesn't open the checkbook. Okay. But it means you speak with one voice. And at the moment, there's a little bit of competition going on.
Gregory McNiff
Oh, sorry, John. I want to move back to exoplanets and particularly what you refer to as, or I guess we in the industry, 51 peg B, what do you think of the most important learnings? After we discovered 51 peg B, which is at the exoplanet, particularly around detection methods and habitability criteria. Habitability criteria? Yeah.
John Willis
You know, the toughest thing in life is always that first first detection or even when, you know, I do a lot of exercise, right. If you tell people if you can get that first push up under your belt or the first pull up, you can do two, you can do three, eventually it will happen. If you can find your first planet, then you can find more. The first 51 peg B is probably most important for just being the first because it taught us this technique works, Right. This is finding things that everybody except one person never expected to find, which is these hot Jupiters going around in these very tight, short period orbits. Most people did not think that was what planets were going to look like. So it was a tremendous surprise. But once we realized that's how some planets form in their exoplanetary systems. Then we could look for the same kind of template. Right. And very quickly we found 2, 3, 4, up to hundreds using that technique. Okay. So in that sense, that's why 51 Peg B as an individual detection was important to me at least. Right. The other thing it did was, and I remember this because I just started grad school in 1995 and you look at the, the list of new papers published every week, every month. It was a much smaller list back then. It was much easier to go through the whole thing. And I'm sat there, I'm reading this paper. What does it say? A Jupiter mass planet orbiting a sun like star. What on earth is this? I remember reading it and it was mind blowing. It's almost science fiction. It goes around every four days. Right. It seemed absolutely nuts. And this gets back to the idea of discovery driven science. How wonderful that we were so wrong and that we at least had the good fortune to be taught by nature how wrong we were. Right. And it's amazing though, when you look back, there's a paper from 1950 by a very, you know, quite influential astronomer who's talking about how we should apply high resolution astronomical spectroscopy over the next coming decades. What are the interesting questions to look for? And in that paper there is a line where he says, you know, it is interesting how we do see stars orbiting other stars at incredibly small radii such that they'll go around each other every four, five, six days. Maybe we should look for planets the same way as well. Crickets chirping in the background. Right. Completely lost and, you know, not followed up on. Right. The folks who were looking for radial velocity planets very sensibly were looking for analogues from our solar system. They were looking for Jupiters and Saturns going around every five, 10 years. And then we discover 51 peg B. And quite literally it's mind blowing. Right. How different nature can be.
Gregory McNiff
Yeah. That's fascinating because the individual who actually thought it was possible was, I think, Otto Struve. And he based that on, I believe, the advancements in spectroscopy which you referenced here and earlier. Could you briefly talk about that? Because I think at one point you say it opened a whole new discipline.
John Willis
Now, more than Otto Struve. What's incredible is one of the pioneers of that planetary finding technique, a chap called Gordon walker, he's at UVic, right. He's emeritus now. So one of the nicest parts of being able to put this book together was to Sit down with him and the chap who was his graduate student at the time, Stevenson Yang, and talk about all of the things that never get written in books, right, about how looking for planets by looking for these stellar wobbles in terms of how the spectrum moves back and forwards with the Doppler shift. It was very speculative stuff, technically incredibly hard. They had to use some really interesting dangerous chemicals in the cameras of their astronomical cameras to work out what was going on. Also the skepticism in the community, right. And how he had to kind of do it. It's almost like his night job and just do other kind of studies in the daytime just to keep the papers coming out. Right. Just to keep the scientific credibility there. And it was. And just helping me understand what were those kind of human pressures leading up to the moment of discovery of 51 peg B. Right. For example, the people who finally announced the discovery, they'd been monitoring that star, oh, for about 10 years or more, right. Looking for a Jupiter or a Saturn like signal, that long period signal, right. And in the end they worked out well, if you compress all of that years of monitoring down to a four day period, that's where they saw the repeating signal. And they presented that at a conference. And people thought that was interesting, but they were very skeptical of that massive compression of data. In the audience were two other astronomers, planet hunters, who the very next month had their own, run a telescope a week and 51 peg was visible. And so they said, you know what, let's look at 51 Peg every night for just an hour or so, get the data we need and let's look at it consistently for one night. And over the period, one week, and over the period of one week, they saw that signal vary and they thought that's it. And they communicated that. And that was what then. That was the tipping point, really hear about this phrase, right? But that was the exact tipping point where you went from a community not believing in planets to then totally believing in the detection. Right. It was then unambiguous and it was, it's really important from, I think, the idea, you know, because we have this portrayal of science as a very linear, organized progression of ideas. And sometimes it is, but often not. And it was really nice to just be directly talking with Gordon and Stevenson with these people and just getting that anecdotal sense of what was it like to be in a scientific revolution.
Gregory McNiff
And I guess, John, that goes back to how young this discipline is, right? I mean, would you say you guys are. I mean, not only the front Lines, but almost. You're the founding fathers of the first generation. And.
John Willis
Well, Gordon is. Yes, but Gordon, I think he's about 87, 88 now. Right. But still absolutely sharp as a tat. Great person to talk to. Right. I actually, the thing I focus on more is when I'm in front of audiences, I'm always focusing on the younger members of the audience. When I say younger, let's take the under 30s right there. But I really emphasize to them how much there is still to play for. And that idea, you remember we talked about the ten year, hundred year, thousand year times. I really tell them what you do in your career, the decisions you make are important because those decisions will be impactful. You will see the results of them. You will get the results, you will make a difference. And the questions you ask, that you see answered will all influence this debate. Right. I don't say you will be the one to find alien life. I don't know know that. Right. But certainly it's so when I emphasize this point of it being a young science, it's not so much that the founding fathers are still around, it's that the founding fathers are in the audience. Right.
Gregory McNiff
Yeah. That's great. I want to. Could you briefly talk about the importance of spectroscopy in improving our search for exoplanets? It seems like it really was. It is a very valuable tool.
John Willis
Oh, spectroscopy is, we think really carefully. We think it's the key to looking at atmospheres. It's the absolute key. Right. If you want to talk about individual molecular species. Is it oxygen? Is it oxygen? Two, is it ozone? Is there methane? Is there anything more complex going on? It's all going to be from spectroscopy. Right. And so you really see this with. I focus a little bit on some of the new technology that's coming on really very quickly, especially this European telescope, the Extremely Large Telescope, the imaginatively named Extremely Large Telescope. Right. It has a meter. That's a mirror. Sorry, that's 42 meters across. Right. And it is an incredible light collecting machine. Because what spectroscopy needs to do these exoplanet atmospheres is photons. You need simply lots and lots of photons. This is why James Webb is doing incredible stuff and it's an incredible facility. But it's only got a 6.5 meter mirror. When you go up to 42 meter mirror, as long as you can deal with the effects of Earth's atmosphere. Right. That is literally a quantum leap in terms of collecting power. Now, if we are within our lifetime, it's going to answer the Questions of exoplanet atmospheres. If we're going to do these thousand exoplanet atmospheres I've told you about, it's going to be with something like the elt. Right. It's that important. Now, let me not detract away from, though, the other important way of finding planets from their transits in front of. So essentially never seeing the planet at all, but just seeing the dip in the brightness from the star when the planet moves in front of the star as we observe it. That is also potentially a way to get a spectrum of the planet atmosphere, but at very low resolution. Right. It's not really going to pick out the very fine detail that more classic spectroscopy will. So there's definitely a tag team approach going on here. But my own, if you ask me, where am I going to put my chips on the table for exoplanet spectroscopy? It's going to be things like the European Extremely Large Telescope, those kind of big facilities.
Gregory McNiff
Got it. And John, I think that's scheduled to be completed next year. It's obviously in Chile, is that correct?
John Willis
Yeah. Now, when exactly first light is going to be? Is it going to be next year, the year after? Always a little bit of uncertainty there. But the important thing is it is close that key.
Gregory McNiff
And we look forward to the next book. Again, I want to go back to some of the case studies in the book because they're fascinating. I want to ask you about meteorites, which you describe as, quote, a physical fragment of cosmic history that comes to us not quite from a forgotten age, but certainly from one only dimly remembered. What clues do meteorites offer us about our earlier environment, and particularly around the timing of water delivery?
John Willis
I mean, quite literally for us, it's like opening a book with our origin story. Right. These are the fragments of the creation of the planets. And so, I mean, I do this a lot when. Because I've got a lot of meteorites. I love meteorites.
Gregory McNiff
No, I was gonna say at your office. I think you mentioned in the book, you've got them all over your office, right?
John Willis
Oh, yeah. I mean, because essentially when I put my meteorite collection together, you can actually buy different meteorites that show physically each of the different stages of the formation of the planets, at least the terrestrial ones in our solar system. You can see the tiny pebbles, you can see the first heating of asteroids. Right. You can see I've even got a chunk of iron that is the center of a failed protoplanet. Right. Because one can follow the physical history now, of course, and I Do this when I talk to a lot of school audiences. Everything around us, everything in your office or for the listeners at home, everything they look around in their environment is made of atoms. All of those atoms are actually 13.8 billion years old, Right? They're all made in the Big Bang in some form. They've been rearranged a little bit, Right. Maybe in the centers of stars over a couple of generations to take their form today. What makes a meteorite special is that thing that you're holding in your hand hasn't changed its shape for 4.5 billion years, right? That is memory, physical memory, that says, this is how I was put together. This is the temperature and pressure at the time. This is the ingredients. So even though we don't know where any one single meteorite came from in the solar system, all of these are kind of. They're like individual stories, news report, witness reports, but from 4.5 billion years ago. And actually, you know, it makes it sound like a monolithic block of time, right? But 4.5 billion years ago, things were happening rather quickly in our solar system. And you can see all of those individual events told. Those stories are told to you by meteorites. I mean, we could do a whole podcast on meteorites, right? They're fascinating, but it's the tangibility of it, Right? And I've seen this so many times when you put a meteorite in somebody's hand and then tell them the story that it tells you, it's earth shattering.
Gregory McNiff
John, I want to move to dolphins, and I actually should have asked you to discuss or describe what the order of the dolphin is. But your last chapter, you talk about dolphins as being a powerful analog for decoding alien communication. And can you talk about dolphin communication system and why you think it might be valuable in helping us understand alien communication?
John Willis
That's a great point, Greg. So, I mean, it's in the chapter on seti, the Search for Extraterrestrial Intelligence, right? And there's kind of two aspects to seti. One is, and let's be honest, if we detect a signal, even if we don't decode it, it's going to be a significant event. That's probably the biggest understatement of our discussion today. It's going to be a significant event even if we don't decode it. However, at least in the kind of popular writing sphere, I've detected a little bit of a preconception among some people that if we get such a signal, decoding it will be in inverted commas, straightforward, given the universality of the language of mathematics, this kind of thing.
Gregory McNiff
Oh, that's interesting.
John Willis
And I kind of. My response to that was, and I think it's literally just written in the book is, well, if aliens are going to be so easy, then dolphins should be child's play. Right. They're not even aliens. Right. We're separated by, what is it, about 90 million years? Yeah. The common ancestor. Right. Should be easy. And it turns out that and I partnered up for a couple of seasons with a group of researchers that's been studying this one population of Atlantic spotted dolphins for 40 years. Right. I tell people it's like the dolphin equivalent of Jane Goodall following the chimpanzees. Right. Very much. This idea of anthropologically studying at a distance, listening, only speak when you're spoken, to only interact when you're interacted with. Right. And the data sets are incredibly rich. It's a wonderful human experience just to spend time with the dolphins, because even though you're meant to be a detached observer, sometimes the dolphins just want to check you out. And that's magical. Right. What have we learned so far? Well, think about what we're doing right now. We are taking a series of tones produced by our vocal cords, and we're putting those tones together into recognizable units that you and I, we would call phonemes. And then groups of those phonemes make repeated patterns that we call words. These are cultural objects, right? Now we can measure the kind of sounds made by dolphins, right? And they use tones and intonation, and this kind of thing we haven't yet recognized Fitness fitted those into kind of a repeating pattern. Think in the analogy. If you're looking at, say, some ancient written text, you would look for repeated phrases, words, symbols that repeat that. We're only just getting to that phrase. What we have worked out is that, for want of a better word, dolphins have names, they have a signature whistle, which is when they interact with their peers. And when their peers interact with them, it's done so with an identifying sort of sound whistle that is pertinent to that individual, and it changes then whatever the individual is. And we can now assign those signature whistles, those names, if you like, to dolphin individuals. It sounds like we've got a mountain to climb, and maybe we have. Right? But this is what babies do, right. We learn to recognize certain patterns when we're young, and then it starts to, you know, build into this structure of meaning. And in fact, it would be a little bit disappointing if it was too easy to just jump in the water and Work out what's going on. We have to spend time with these creatures. We've got to be open minded and aware, and we have to make sure that they have a stable environment in which to live and grow.
Gregory McNiff
Wonderful chapter and great point. John, I'd be remiss if I didn't ask you about the Drake Equation and why you say it keeps us honest. You can describe it, but it's 60 years old. And it's basically, I guess, an attempt to assign some type of probability to extraterrestrial life. Can you talk a little bit about it and why you say it keeps us honest?
John Willis
Well, I mean, it's great that we've got so much story of its history. Frank Drake wrote down the Drake Equation. First time it ever appeared was on a blackboard at a small meeting at a radio observatory in West Virginia. There's about 10 people present, all different disciplines, and they were interested in, you know, well, what factors determine if there's going to be intelligent alien life out there. And so he wrote down, he wanted a summary. And being a good scientist, he thought the easiest way to write this down is an equation and I'm going to break it down. And what the Drake Equation is, it's a classic example of taking one big unknown and breaking it down into, let's say, 10 smaller unknowns that might be answerable. Okay. And the term, I'm not going to try and go through all of the terms for you, but it starts off with how many stars are being formed every year in the Milky Way? What fraction of stars have planets? What fraction of planets go on to evolve life, et cetera, et cetera. By the time you get to what fraction of planets with life develop intelligent communicating aliens. It's a way of breaking things apart. It keeps us honest because he knew and the other people in the room knew they didn't have answers to everything, but it was still important to write those down because they're kind of like placeholders. This is why I say it keeps us honest, because it's not about showing how clever you are. It's about showing where you need to do the work in the future. Right. And so when he wrote down that equation, the only number that they knew with any certainty was how many stars or what mass of stars is being produced in the Milky Way every year. Right. Astronomers were able to measure that the next term, what fraction of stars have planets was completely unknown. Right. And even you'd be ridiculed for studying it. Right. As some of them were. And then that takes us Forward. So that was written down in 1961, 1995, you discover your first planet around another star, 51 Pegb. About 30 years later, 20, 25. We now have a pretty good idea that every star has a planet around it on average. And so to some people, they look at the Drake equation and say, but there's so much more that we don't know. Isn't that intimidating? And whereas I look at it and I say we answer the term in the Drake equation. Isn't that amazing? Right. And so I very rarely present the. I don't think I ever actually present the Drake equation as something you plug numbers into and get an answer. Say, that's the answer. That's how many aliens there are. I try to use it in what I think is the way Frank originally wrote it down is saying, what do we need to be thinking about?
Gregory McNiff
Yeah, And John, I just want to follow up there. You talked about the number of variables in it. You actually propose a much more simpler one. You call it the optimistic limit of the equation where N equals l. And I think that refers to how many number of years we could be to a civilization that we that might exist and transmit communication. But can you briefly say why you'd reduce the equation to N equals L?
John Willis
Well, that wasn't even me. Right. So when Frank wrote down that equation, the 10 people or so in the room, they had all really interesting backgrounds, right? There was a young Carl Sagan there. There were some astronomers, There were some people who were starting to think about planets. There was a biochemist, there was a couple of computer scientists. There was even a dolphin researcher. This is why they whimsically called themselves the daughter of the dolphin right after this meeting. And they did what any scientist would do when confronted with a new speculative problem. They ballparked it. They looked at the terms in the Drake equation and they ballparked it. And I think one could say it was optimistic. But they looked at each of those terms and said, and each of those terms can be written as a fraction. So a number between 0 and 1. Right. And they actually said, you know, we don't have any strong evidence to the contrary that says that these numbers should be anything other than close to one. And so when they put that in there, the Drake Equation, as classically written, reduces to the number of, pardon me, the number of communicating civilizations out there is pretty much equal to the typical lifetime of a civilization. If a civilization is communicating for 50,000 years, there'll be 50,000 communicating civilizations in the Milky Way. Right? So now, the way I present that, I certainly didn't come up with that analysis. Right. I don't have any claim to that, but I call it, you can think of it as the optimistic limit. You can't get any more than that. I do think it's kind of cool though, because it places the emphasis on the civilization. How long do you think we're going to be communicating for? Well, we've been communicating since, well, you know, just around the time of World War II. We started, you know, beaming radio waves into space just before. Right. So let's call that coming on close to 100 years. Now, would we like it to be 200? Well, if we'd like it to be 200 years or 300 years or 1000 years. That's an interesting way of looking at the Drake equation because it puts the emphasis on what are you doing on planet Earth now? What should we do to make sure we keep broadcasting? And then that opens up a parallel but nonetheless interesting discussion is, well, we're actually living on this amazing living world, this pale blue data point. Right. You know, perhaps we want to bear that in mind if we want to continue broadcasting.
Gregory McNiff
Yeah, yeah. That's a nice way to end the interview as we opened it about, you know, our actions have consequences. And we Talked about the 40 year project, Project mission in the beginning and that means planning now and asking the right questions. But John, this has been a great interview. Thank you so much for your time and, you know, taking the time to explore these questions and share your answers with us. I think the book really is just fascinating in terms of understanding both life and the universe and our search for it, you know, outside of planet Earth. Really enjoyed it and thank you very much.
John Willis
Well, thank you very much as well. It's a pleasure to be here. Here we have the Limu imu in.
Marshall Po
Its natural habitat helping people customize their car insurance and save hundreds with Liberty Liberty Mutual. Fascinating. It's accompanied by his natural ally, Doug Limu.
Gregory McNiff
Is that guy with the binoculars watching us?
John Willis
Cut the camera. They see us.
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John Willis
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John Willis
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Podcast: New Books Network
Host: Gregory McNiff
Guest: Jon Willis, author of The Pale Blue Data Point: An Earth-Based Perspective on the Search for Alien Life (U Chicago Press, 2025)
Date: December 3, 2025
This episode of the New Books Network explores Jon Willis's book, The Pale Blue Data Point, which presents a grounded, fieldwork-based approach to the search for extraterrestrial life. Willis, an astronomer at the University of Victoria, emphasizes uniting planetary science, geology, biology, and history to sharpen our understanding of what kinds of evidence would truly indicate life beyond Earth.
“The thing it hadn’t done is it hadn’t really answered the question, what does an astrobiologist actually do?” (03:16, Jon Willis)
“What I have noticed is folks are much better informed... There’s a real appetite for something a bit meaty...” (06:20, Jon Willis)
“Does that mean we’re going to find life in the next 10 years, the next 30 years? I have no idea. Absolutely no idea. And I’m totally honest about that.” (11:07, Jon Willis)
“The Fermi paradox is a little bit arrogant, right? In the sense that it assumes we’d know what we were looking at.” (17:42, Jon Willis)
“It’s a wonderful question that doesn’t have a clear answer. When does chemistry become biology? What is that point?” (21:13, Jon Willis)
“Can I come back when we’ve looked at the first thousand and tell you?” (30:39, Jon Willis)
“It’s going to come to maturity next decade, next two, three, four decades, it’s going to become more commonplace.” (34:36, Jon Willis)
“Bringing rocks back was going to stop us doing a lot of other things... there wasn’t that cohesion in the community.” (52:14, Jon Willis)
“If aliens are going to be so easy, then dolphins should be child’s play. They’re not even aliens. Turns out, it's not.” (69:27, Jon Willis)
“[It] keeps us honest, because it’s not about showing how clever you are. It's about showing where you need to do the work in the future.” (72:36, Jon Willis)
On Public Interest:
“You cannot fool a middle school kid, right? If they're interested... and they've got some background... they're going to be a very well informed and critical audience.” (07:41, John Willis)
On the Search’s Timeline:
“If you want to get people excited about a space mission, say to Enceladus... you're looking at 40 years—from first light bulb moment to the last line of your scientific paper.” (12:28, John Willis)
On Discovery-Driven Science:
“It doesn't matter what your preconception is. Nature’s going to tell you how things work, and your job as a discovery scientist is to respect that process.” (32:11, Jon Willis)
On the Challenge of Defining Life:
“What I would say is, in the past, we have seen that metabolism test applied as the sole test of life... but it also has limitations as well.” (24:06, Jon Willis)
On SETI and Communication:
“Even if we don't decode [an alien signal], it's going to be a significant event... If aliens are going to be so easy, then dolphins should be child’s play. Turns out, it’s not.” (69:27, Jon Willis)
On the Drake Equation:
“It keeps us honest, because it’s not about showing how clever you are. It's about showing where you need to do the work in the future.” (72:36, Jon Willis)
Willis presents a grounded, self-critical, and practical vision for astrobiology, mixing wonder, realism, and humility. He counsels patience and an evidence-based approach rooted in Earth's lessons, while reminding listeners that the field is young, dynamic, and still open to game-changing discovery. The search for alien life, above all, is a collective scientific adventure—one that both reflects and deepens our understanding of ourselves and our planet.