Nobel Prize Conversations

”I don’t think it’s my job or anybody’s job to try to convince other people of the righteousness of my opinion. I think it’s each person’s job to figure out how they look at the world”

Listen to a podcast with astrophysicist John Mather, where he speaks about space and if we will be going to Mars in the future. Mather also shares good advice to young researchers on how to prioritise projects. The movie ’Gravity’ is another topic that comes up – how scientifically accurate is that movie? 

Listen as we take you back to this conversation with Mather, recorded in 2014 as part of the series ‘Nobel Prize talks’. The host of this podcast is nobelprize.org’s Adam Smith, joined by Clare Brilliant.

Below you find a transcript of the podcast interview. The transcript was created using speech recognition software. While it has been reviewed by human transcribers, it may contain errors.

Clare Brilliant: Welcome to Nobel Prize Conversations. I’m Claire. Brilliant and I’m here with our host Adam Smith. Hi, Adam.  

Adam Smith: Hello, Clare. 

Brilliant: We’ve been digging through our archives of previously recorded conversations, and today we’ll be hearing from John Mather. When did you speak to him, Adam?  

Smith: The conversation was recorded in 2014. He’d been awarded the Nobel Prize in physics back in 2006 of his work on the Coase satellite and mapping the cosmic microwave background radiation. In 2014, he was busy with another satellite. 

Brilliant: I guess he’d had a few years to get used to the prize. 

Smith: Yes. he had indeed, the prize tended not to interfere too much in his work because he’s very focused and putting together these teams that have to get satellites to actually work, get launched and work in space. 

Brilliant: I think that really comes across in the conversation, the immense task of bringing these huge teams of people together and how dedicated he’s to that. 

Smith: Exactly. He was building the James Webb Space telescope back in 2014 which now of course has been launched and is sitting a million miles from earth mapping deep regions of space and revealing all sorts of amazing things. 

Brilliant: Yes. It was really interesting to him talk about the potential of what he thinks these satellites are going to tell us. 

Smith: Absolutely. I mean, the data’s coming back now and showing that water in the atmosphere of exoplanets orbiting stars in distant constellations or indeed the signatures of carbon containing molecules in those atmospheres. He feels that such signatures will be the footprint of life elsewhere. We will eventually find. 

Brilliant: I really found it fascinating, his conviction that we will find extra-terrestrial life. 

Smith: I also love his observation that extraterrestrial life may, if it becomes advanced, actually not emit much of a signal that he says, although we beam energy into space all the time, that may be just a stage in our lack of advancement, and once we get past this stage, we might become quieter, if you see what I mean. Fascinating. 

Brilliant: Really fascinating. 

Smith: Yes. He says that he can’t ever remember not wanting to be a scientist, and you can certainly tell that from listening to him. So let’s tune into the episode now. 

MUSIC  

John Mather: Morning. 

Smith: You’ve just come back from the Intel Science and Engineering Fair in Los Angeles. 

Mather: Yes, indeed. It was a pretty amazing group of young people there. Very inventive, very creative, very self-propelled young people. Several of them told me no, they did it themselves. Their parents didn’t even understand what they had done. If the world is to be based on what these young people are doing, we’re in fine shape. 

Smith: That’s the thing. In a way one might associate doing science projects with a sort of old fashioned approach. Certainly lots of the laureates we speak to did great science projects when they were young. But nowadays it’s really good to hear that young people are still doing science projects in their spare time. 

Mather: Oh, well, yes. They just want to do these things. They think of something, they’re inspired. They look things up on the internet. They take online courses. They go far beyond what their school teachers are leading them to do. They’re amazing. 

Smith: It’s been going a long time, this science fair, but it’s becoming a more and more international affair. Is that right? 

Mather: Yes. I think they told me there were 1600 people from 80 countries. Yes, it’s indeed huge. 

Smith: Anybody you saw you wanted to recruit? 

Mather: Oh, there are lots of really smart people there. One of the astronomers that I know is already going to be a summer intern at NASA Goddard where I work. We certainly recruit right people occasionally, but before that we’re ready to hire them into NASA we need them to have college degrees mostly. 

Smith: Yes.  

Mather: Of course. We’re just eager to see what they’re going to do next. 

Smith: Did you tinker with science projects when you were young? 

Mather: Yes, I participated in some. I know in ninth grade I had a project about nutrition and rats. I kept eight baby rats under the table in the kitchen for a few weeks while I found out what they did on different kinds of food. Later on, I think in 11th grade, I had a project about trying to measure the orbits of asteroids. I would say that it was a complete failure, but it was fun to try. 

Smith: Were there any mishaps with your projects apart from failures, actual disasters? 

Mather: No. No serious disasters. Nobody hurt.  

Smith: Were you in a very supportive scientific environment when you were doing these things? Or were you out on your own? 

Mather: Yes and no. My dad is a scientist, so he certainly was encouraging. My mother was encouraging, but they didn’t know personally very much about what I wanted to do. My dad did teach me statistics in ninth grade, so I learned about analysis of variance from him. That was a good thing to know about. My other project was asteroid orbit. Now I was definitely on my own.

Smith: When you were doing these things, had you already decided that you wanted to become a scientist? 

Mather: I don’t know if I ever decided that. I think it’s more like I noticed that. I can’t remember ever not wanting to be a scientist.  

Smith: Really. Even when you were very young? 

Mather: I don’t remember anything when I was very young, but I know around third or fourth grade, I was already reading everything I could about science. 

Smith: Gosh. So that’s eight or nine years old and you were already… Wow. That must’ve been pretty unusual. 

Mather: I suppose so. But I have no way to tell. I would expect that many of the science fair students there also started there when they were eight or nine years old. 

Smith: Can you summarise what it is about science that you found and find so fascinating? 

Mather: Several things. One is that there’s a sense of discovery that you can just find out things that nobody knows before. If you find them yourself, and you’re the first one to find them, that sounds really important. Maybe it’ll help change the world for the better in some way. This idea that it’s also a little dangerous. I grew up on stories of Galileo and Darwin and the fact that they got in trouble just proved to me that it was important. 

Smith: I love the idea of a nine-year-old boy reading about science and thinking of it as a kind of wonderful, dangerous profession. 

Mather: Growing up here in the States where there’s so many fundamentalists around and people who would disagree with you if you wanted to tell them about evolution. I used to have dreams about that. Suppose I were teaching in school and I was teaching the students about evolution. It wasn’t so long ago we had our trial, jury trial over here about whether it was okay to teach evolution. Anyway, we keep on fighting that fight. 

Smith: Exactly. Because things haven’t changed all that much. I mean, they’re not jury trials now, but there’s still a big debate. 

Mather: Yes. 

Smith: Do you still feel yourself to be fighting that battle on a daily basis to try and get people to attention? 

Mather: Actually, no. I don’t fight it on a daily basis. I just do what I do. I don’t think it’s my job or anybody’s job to try to convince other people of the righteousness of my opinion. I think it’s each person’s job to figure out how they look at the world. 

MUSIC 

Smith: One of the things that you had to have when you eventually came to be the lead scientist, making sure that the Kobe Satellite Project actually worked was an incredible degree amount of confidence, I would’ve thought. 

Mather: I actually don’t think so. Confidence, I think, is the sort of wrong feeling to convey. I think more it’s a sense of the importance of the work and the determination to make it to work. So rather than confidence, one has to have persistence and determination and certain degree of worry. If you don’t worry, then you don’t understand how hard the job is. In fact, it’s the job of our space engineering experts to make sure that something works. They have to spend a vast amount of effort to think of everything that could go wrong and make sure that doesn’t happen. It’s like the opposite of confidence.  

Smith: Okay. But when somebody handed you the task of pulling all these people together and acting as the kind of center point for everybody, building Kobe, putting everyone in the same direction. They must have seen in you the sort of person who could inspire confidence in others, at least. 

Mather: Yes. I guess they must have. It’s hard for me to remember those days. When I was hired into NASA to work on this project I was only 30 years old. So I thought they don’t have much basis for confidence. It’s just I’m willing to stand here and say I’m going to do this project. They were willing to bring in the top talent to make it happen. I didn’t actually organise all of that. Top engineering management did that. I think what they saw was a young team of scientists with some good ideas, and they thought it was important enough to recruit the best engineers that they could to make sure that it would happen. So it’s much more an organisational process with other people’s leadership than it is me. 

Smith: Right. Is that, in a way, the secret of NASA’s success? That they’re able to organise the right teams of people to make these projects work? 

Mather: Yes, I think so. It’s NASA, it’s every other large organisation that succeeds has to have a set of people and a culture and a process that leads to success. If you were to just set one bright person in the middle of the world and say now build me a telescope it would be a very long time of recruiting the top talent and organising them to find out who could do what and making sure that things would work. An organisation like NASA or its great contractors, all of them have this collection of people and process at the same time. There’s no way we could be building a great telescope today, just because a few people were smart. It takes this huge crowd of people with history who know how to do things. 

Smith: When you finished the project, when Cobe finally delivered, in your case, the evidence that the CMBR had a black body form, do you remember the moment of finishing that project, of the data coming in? 

Mather: Well yes and no. There are a number of special moments. One is of course the launch. And you realise that no, it did not explode. 

Smith: Yes. 

Mather: Then a few hours later, you realise and signals have come back and you say, well, the satellite’s alive. Then it takes a few days before we are able to open the cover on the hibi cryostat to find out if everything works. Then two days after that things are not behaving quite right. We have to debug and figure out what to do about all that. But within a couple of weeks, I think we were already getting our first interferogram and our first data saying, yes, things are functioning. I do have somewhere in my keepsakes a signed interferogram where my team members working late into the night were able to make a printout that showed the data were coming in correctly. That’s a special moment. It didn’t take too long after that before we realised we could make the famous spectrum that we presented six weeks after launch at the Astronomical Society. 

Mather: I think when I presented that spectrum and we got a standing ovation for it, I came to understand that it was much more important than I had ever guessed. That was pretty special. Then two years later, as you know, we put forward our first maps of the sky. Again it was hugely important to the world because it was a map that they could print on the front end of the newspaper, and it was got even more publicity than before. I’d like to, by the way, mention that there was a process leading to that. About six months before that event Ned Wright, who was a member of our science team, had done his own personal analysis of the microwave map, and showed the science team that yes, it had spots on it. Our conclusion was that’s probably right, but we better check it. We spent the next six months verifying that it was correct before we could go public with it. 

Smith: That six months was important. 

Mather: Yes. There’s a history of people going off half-cocked in science. The more important it is, the less careful they get sometimes. That was in the days of poly water, which was apparently a fraud and cold fusion, which was apparently another fraud. We knew for sure we’d better not be announcing something that would have to be retracted. That’s why we were so careful. 

Smith: When you come to the end of a project like that, and you had lived with a cosmic microwave background radiation for a long time, because you’d tried to make a map from balloon borne experiments prior to you ever beginning on the satellite project. When you come to the end of it, it must be very hard to conceive of starting something else. You finished a major chunk of your life’s work. How do you begin again? 

Mather: That was a tricky question. At the end of the Kobe project, I did indeed think, what am I going to do now? I started poking around at different ideas. I thought for a while, well, maybe you know, they were planning the Spitzer Telescope at the time. My friend said, well, you know, it’s not a big enough telescope. We need to make a bigger one. I started making sketches of how you would unfold a telescope in outer space. I had in mind something only about two meters across, which was about a little over twice what the size of Spitzer Telescope is. So I thought, well, that would be fun. I presented my ideas to a small colloquium, and my friend said, oh, we’ll never do that. That’s much too hard. A couple years after that, I got a phone call from NASA headquarters that it said, it’s time to start the new telescope. What turned into the James Webb Space Telescope would I like to participate. They needed a proposal the next day for how to proceed. So I thought, I certainly can tell what’s to do now. 

Smith: Did you have your scrap of paper where you had your doodles ready?  

Mather: Yes.  

Smith: When will the James Webb Space telescope launch? 

Mather: It’s planned for October, 2018. So just over four years from now. We will have the observatory at the launch site. That’s the plan. 

Smith: And the launch site will be where? 

Mather: It’s in French Biana. It’s on the equator in South America because the European Space Agency is buying the rocket for this mission, and that’s where they launch.  

Smith: How assured is that rocket launch? Is there a huge competition for those, or can you really book in advance like that and say, this is going to be a model? 

Mather: No, we can book those in advance. It’s a commercial product. They launch them many times a year. I think they have a track record of about 50 in a row, good runs. We’re pretty pleased with that. It’s about as good as it gets in the space business. 

Smith: Do you have a kind of backup plan for if you happen to be the rocket that does explode?  

Mather: No. We don’t even think about that. 

Smith: Okay, let’s not talk about that.  

Mather: Better not to think about that. Just make sure the one that we have does the right thing. 

Smith: Okay. When it gets into space and becomes functional, what will it see that hasn’t been seen before? 

Mather: It’s designed to do infrared astronomy, which we accomplished by making the telescope cold so it doesn’t emit infrared light itself. It’s also very large. It’ll be able to look much farther out into space and farther back in time to look for the first objects that formed after the Big Bang, the first stars, the first galaxies, the first black holes, the first supernova, the first everything. Then try to understand how that led to our existence today. How did the stars explode and the material fall back into make new generations of stars and planets? How are stars being formed today? We know where they’re doing it nearby, and so let’s please have a look inside those dust clouds, see them do it. Ideally to learn a lot more about planets planetary systems. So for instance tracking down all the planets that have been discovered by the Kepler. We’re even developing a NASA mission called Tess, which is a transiting exoplanet survey satellite, I think. Anyway, it will basically extend the Kepler technique to all the nearest and brightest stars so that with luck, we’ll have a pretty nearby candidate object that might be like Earth. If we are extremely lucky, then we will find one that has enough water vapor to have an ocean, and that will be remarkable. 

Smith: From the James Webb, you are going to be able to see planets as they transit across their stars and tell whether they have enough water vapor to potentially have oceans. 

Mather: Yes. Isn’t that amazing? 

Smith: It’s indeed. 

Mather: When we first conceived the telescope, we didn’t know that was possible. We’ve only made the tiniest design changes to make it possible for the telescope to see those things. 

Smith: Is it the case that you have a kind of raft of ideas coming in all the time for how you can improve it, and what else you can add to it to the mission? Do you have to have a shutdown time at which you say, after this point, no more ideas, let’s just do what we’re doing. 

Mather: Pretty much the scientific requirements were frozen in about 2002. So hardly any changes have been made since. 

Smith: That’s amazing. That’s a very long time. Why does it have to be set so far ahead of the 2018 launch? 

Mather: Well, of course, in 2002, we didn’t think the launch would be in 2018. We thought we had much shorter time. But it was still the correct plan because you can’t build stuff while you keep changing your mind. So you have to decide what you’re going to do. So we did, however, have to continue to demonstrate our technologies. We had 10 different things that had to be invented and perfected before we could use them on this observatory. It took until 2007 before they were even ready to trust. That included things like the mirrors, the two kinds of infrared detectors that we need, a very low temperature amplifier and a computer to run the detectors. The ability to unfold the telescope in space and focus it after launch, all of those things had to be understood before you could even finish the design. So it’s very intimidating. There’s a plenty of good reason why you don’t keep changing your mind. 

Smith: When people talk about the Apollo missions in the sixties, they look back and they say that it was an unbelievable feat. It happened, but the advancement in technology in the lead up to the moon missions was so great that it was just unlike any kind of invention that had been seen before or pace of invention. Is it like that every time you do one of these, that you conceive things that have to be invented to make this project work? It seems incredible when you conceive them that it can be done within the time, but somehow people find the resources to make it happen? 

Mather: I don’t know about every time because every mission is different. We have different requirements, for instance for studying the earth than we do for doing astronomy. For earth science we need to have continuity where we know that the new equipment agrees with the old equipment as measuring trends of the earth is very important. You want to know if it’s getting warmer or colder,  wetter or drier, dusty or less dusty. All those things require continuity. For that territory sometimes less change is good. Many more of the same kinds of equipment is good for astronomy. We push the frontiers by building something that’s more powerful than before. They’re infrequent enough that technology changes a lot in between. For instance the next even bigger telescope after the James Webb Telescope would probably be built specifically optimised to study those planets around other stars, the exoplanets. That probably means it needs to be two or three times as large as the James Webb telescope. When we get to do that, it’ll take yet another set of inventions. 

Smith: Do you have to start designing the next one before you’ve got the current one up and working so that you have to predict what you’re going to see from this experiment and use that to design the next experiment without actually knowing whether this one is going to give you what you need? 

Mather: I think actually our challenge is a little different. The most uncertain thing about these great telescopes is can we do them? People are quite concerned about what happens if it doesn’t work. I think that’s the number one thing to establish that it’s possible for an organisation to produce a working product, even if it is complicated. I think setting out the next kind of science to do isn’t actually so hard to figure out because we already have good evidence for what it should be. 

MUSIC  

Smith: How do you decide which experiments to do? How do you prioritise and given the vast number of possibilities, and whether NASA or invest in space missions or whether they invest in satellite technology? How do you begin to decide? 

Mather: For a particular mission like the James Webb telescope we set out committees of scientists to say, well, what’s most important to you? What do you think we’ll be wanting to do in 10 or 20 or 30 years from now? How do you know that somebody else isn’t going to do it? We looked for the things that could never be done in any other way. That sort of basic idea, don’t do something somebody else can do. It’s too hard and takes too long to cut up a space mission. We could tell that nobody was going to do this particular science because nobody could see through the earth atmosphere at the wavelength that we were working on. Whatever progress that was going to be done, had to be done with a space mission. That told us our idea was unique. That’s if you want to say, how do you choose what general idea to pursue what kind of observatory? We have giant committees in the US. They meet every 10 years. They produce a survey of all kinds of astronomy and what should be done next. Europe has its own process for doing those things and so do individual countries like the UK. Committees of scientists get together and argue. That’s a good thing. 

Smith: Is there a big debate about whether it’s better to do missions that have great popular appeal? I suppose searching for exoplanets is a good one as far as the public are concerned. Certainly putting people onto Mars would have popular appeal or projects that are more for the scientist, if you like, where the popular appeal is not quite so obvious. 

Mather: I don’t know. Clearly the public pays for these things with their taxes for large NASA and European missions. If we’re sending people to Mars, it may happen differently because it takes a different way to go than what we’ve been thinking about. For instance there’s a company called SpaceX where they’ve been making good progress on lowering the price of space launches. The company owner, Mr. Elon Musk, says that he’s motivated by the desire to go personally to Mars. That may actually change our whole interplanetary travel process if he’s successful. 

Smith: Do you think he will be? 

Mather: He is doing awfully well now, so I encouraged the thought that he can do well. Travel to Mars is dangerous no matter how you think of it. But we can do better. So maybe we will. 

Smith: Did you ever entertain the thought yourself of trying to get up into space? 

Mather: Not very much. I’m not very much of an athlete. I think I would be a little concerned about surviving the launch, but if I could go safely and comfortably, of course, I would want to go. 

Smith: I wanted to ask you just one film related question. Having watched Gravity on an airplane journey myself the other day, is that picture that’s portrayed in the film, gravity of a rather crowded near Earth orbit with a potential of things to bump into each other, satellites bump into each other, becoming true? Are we getting a bit crowded in the near Earth space? 

Mather: It is crowded, and we’ve already had a one definite accident where two satellites collided, and they weren’t even trying. They were just a random accident. Of course, that showers the area with debris. We’ve had a couple of events where satellites were intentionally shot at by the people that owned them, one US to prove the ability to do it and one Chinese. In both cases debris occurs and this has a significant hazard for astronauts. There’s more and more of this debris up there. It’s not imminent, but certainly it’s predictable that there will be a time when there’s so much debris that you can’t go there anymore. 

Smith: That will happen? There will be such a time? 

Mather: It depends on what people do. We could continue to work on ways of reducing that debris to go out and catch it or destroy it, or send it into the atmosphere, or various things we could do that would help. 

Smith: Hard to conceive, because… 

Mather: Now you probably already know that there’s an international treaty that requires all satellites in those areas to be disposed of safely when they’re done. But bad things still happen. 

Smith: I can’t begin to see how you might, you might begin to get rid of the debris. You’d need some sort of vast vacuum cleaner sucking it all up.  

Mather: Yes, you do. There are a lot of ideas but none of them turned out to be very… none have been chosen yet, I think. 

Smith: I mean, presumably it’s a very important problem to solve, because otherwise you also can’t put satellites up because they’re gonna bump into the debris every so often. 

Mather: Yeah. It’s harder than it sounds. Let’s put it that way.  

Smith: Yes, quite so. One of the other things you spoke about with reference to James Webb, was that it’s going to look further back in time to the formation of some of the earliest large structures in the universe. That’s an extraordinary thing to sort of begin to conceive. I wanted to ask, do you stop every so often and just marvel at the wonder of what you are looking at and what you’re trying to look at? The enormity of it? 

Mather: I do every day. I’m thinking about the marvels of what I’m looking at. To me, the even more mysterious part is the biological world. I’ve studied physics long enough to have some idea of how these things function and how we’re now able to simulate in the computers how galaxies form and things like that. How stars form how planets form. When I listen to my biologist friends talk about what they’re working on, I’m thinking how completely astonishing it all is and how unutterably complex it all is. How almost miraculous it seems, even when you understand about evolution. There’s just no end to the complexity of what we have inside us. To think about the fact that we’re probably all descended from the same original single cell living thing 3.8 billion years ago. Here we are continuing 3.8 billion years of life. So you and I, and the bacteria and the viruses are all direct relatives.  

Smith: It’s very nicely said, very beautifully said. But one of the strange things perhaps, is that people in general, I would say are much more grabbed by the wonders of the universe than they are by the wonders of life on Earth. If you look at sort of newspaper headlines, as soon as there’s a new beautiful picture of the universe, or some fact that brings out the enormity of space, it hits headlines and people lap it up. Somehow the marvel of life on Earth is perhaps more mundane to people. They see it, they sort of encounter it every day, and somehow they’re used to it, and they don’t tend to be as amazed by it I would say. 

Mather: I know, that’s true. We make beautiful pictures in our astronomy, and people are inspired by those pictures. How life works is just much more complex than you could possibly imagine. So it’s hard to make a pretty picture of it. But if you know a little bit about it, you say, oh, how completely amazing. Because life is more, is far more than I ever knew. It’s done digitally. We have digital code in our RNA and our DNA. The little tiny computer hardware inside each cell, they read the code and do things with it. Things are switched on and off digitally. Nobody gets excited about computer code, except maybe the people who write it. We just are, we just use it without knowing anything about the marvels inside it. People aren’t amazed at the wonderful engineering inside their cars either. But 200 years ago, we didn’t have any. That’s an equally mysterious and wonderful story. 

MUSIC 

Smith: Is there one undiscovered question in space research in astronomy that you very much hope to see answered in your career? 

Mather: I’d say every day when somebody asks me that question, I have a different answer, because there’s so many wonderful mysteries out there. I’ll just say a few that are really intriguing and there’s a chance that we can make some good progress. What are the dark matter and the dark energy? There’s a fair chance that we can have a reaction of some kind of dark matter in a laboratory setting. There are several experiments worldwide hunting for that. Maybe we’ll know more about the dark matter and maybe we’ll finally get a satisfactory unifying theory of physics that says what it is and what it’s supposed to be, and makes some decent predictions that would help the closer to home. Are we the only ones here in the universe, or is this planet the only one that’s alive? Or are there many planets that are alive? I’ll tell you my prediction is that wherever there’s liquid water there’s life. That’s what I think. And how would we know? We have to go a few places where you can examine this. On Mars, there at least was, and probably still is, liquid water in places. I think when we dig carefully and well, we will discover signs of life on Mars. We know we can get there with the equipment to do that. 

Smith: Let me just explore that question a little bit more. Where will the liquid water be on Mars, do you think? 

Mather: It’s not on the surface because it’s too cold and too dry, but underground, there could be liquid water in the rock. 

Smith: When do you think it is likely that we might be able to get to that place? 

Mather: Oh, that’s pretty hard. It depends on how far down into the rock you think you might have to drill, or whether you think some signs of it will be on the surface. I think we have to send a continuing series of probes to go looking around. We have chemistry labs on the surface of Mars now. In fact one of them was built right here at Goddard Space Flight Center. My colleagues are every day rehearsing in their lab in Greenbelt, Maryland, how to do the analysis on Mars. There will be a continuing series of miniaturized instruments to go to Mars to do these analyses. Another great hope that that team has there is to bring back some rocks so we can study them here at home, with even more powerful equipment. Bringing rocks home, that’s clearly a major job. It’s difficult and expensive also, but it’s still not nearly as difficult and expensive as getting people to Mars and back. I think it’s clearly a next step in our in our travel plan to Mars is to learn how to go there with robots and bring back rocks for study.  

Smith: Sorry, now that we’re on this topic of extra terrestrial life, and given that you surely expect to find liquid water on innumerable planets in time, and thus there are innumerable points in the universe where there is life, do you think it’s odd that there has been no sign of that life seen in emissions that we’ve been looking for in space? 

Mather: No, I don’t think it’s odd. I think it is what I would expect. There’s no particular reason for a civilization to be transmitting large amounts of radio power out into space. We do it here on earth sort of by accident. We need radars, we have televisions. It wouldn’t surprise me a bit if in another century that we abandoned all that stuff because there’s some other better way to do it. I think it’s quite possible that if there are civilisations out there carrying on a high technology civilisation that there’s no reason for them to be sending us a signal. 

Smith: Yes. It’s very hard to think of things in any other way than the way you live, isn’t it? So I suppose, all future predictions sort of see us going on just as we are, but we won’t be. 

Mather: Anyway, I think space is also very large. I think that there’s a suggestion here that even if life is common, that intelligent life is not common. The evidence that we have here on Earth is that very soon after the asteroid bombardment ended about 3.8 billion years ago we got signs of life in the fossils. Probably it was very quick here after life could occur with liquid water that we had. So that says the formation of life is quick, but then it took the rest of history for us to get here. Modern civilisation has only been here, maybe you call it a hundred years, where we could transmit radio power which out of the age of the universe is just like nothing. We’re so new and so brief here, it’s hard to tell where we can go or what we will do. 

Smith: Yes. It is a good point that, what is it? Is it three and a half billion years since life first began on Earth, perhaps? How would that compare to the normal time that it would take an intelligent civilisation to occur on any planet? How long do planets normally have before something happens? 

Mather: Right. Good question. No one doesn’t know. We have our only one case that we’ve noticed, which is ourselves. There are many serious writers who think that our case is rare. There’s a book called ‘Rare Earth’ that makes the case for that. That’s not the only one. I think they’re probably right that the history of events here on the surface of the earth is unusual. We have a particularly unusual situation with a large moon, which stabilises the spin axis of the earth. We have volcanism and continental drift and just the right amount of water to have both land and ocean. Those might all be necessary for the formation of intelligent life. We don’t know, but what if all those are necessary, then it would be rare. 

Smith: Do you think you might see extraterrestrial life on Mars in your lifetime? 

Mather: I think quite so. I think we could but I don’t know. Because Mars is large, if you were to sit down a probe in the desert here on earth, you might have a hard time discovering that there was something underground that was alive here too.  

Smith: Yes.  

Mather: Each probe can only examine a few square meters of territory at that, out of millions of square kilometers. If you don’t find it the first time, it doesn’t mean there’s none. It just means you didn’t find it. 

Adam Smith: I suppose every scientist likes to point out how each time you ask a question, the answer just leads to more questions. It couldn’t be more true in the case of astronomy and space exploration and cosmology.  

Mather: Certainly true. Absolutely. But that’s one of the great marvels of science too, that when you see a little farther, you see that everything is more complex. I think it’s a fair guide to science to figure everything is more complex than you can possibly imagine. If you can just peel off another layer you’ll have more work to do. 

Smith: Yes. That’s a great advertisement for a career in science, isn’t it? 

Mather: Yes. Our job is not going to be done anytime soon. 

Smith: Good. What a fascinating conversation. At least for me. I’ve enjoyed it tremendously. 

Mather: Thank you, Adam. I love talking with you. 

Smith: Thank you so much.  

MUSIC

Brilliant: This podcast was presented by Nobel Prize Conversations. If you’d like to know more about John Mather, you can go to nobelprize.org. Where you’ll find a wealth of information about the prizes and the people behind the discoveries. 

Nobel Prize Conversations is a podcast series with Adam Smith, a co-production of FILT and Nobel Prize Outreach. The producer for Nobel Prize Talks was Magnus Gylje. The editorial team for this encore production includes Andrew Hart, Olivia Lundqvist and me, Clare Brilliant. Music by Epidemic Sound. You can find previous seasons and conversations on Acast or wherever you listen to podcasts. Thanks for listening. 

Nobel Prize Conversations is produced in cooperation with Fundación Ramón Areces.

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