The religions of the world – including Jewish tradition – give humanity a central role. The clash between science and religion is fundamentally a consequence of science demoting humanity from this pedestal. Astronomy, which has been central to the growth of science in the West, has taught us that we are not at the center of anything, at least in terms of physics and chemistry. We have learned that we are in a corner of the universe that is typical, not exceptional. But is the same true of biology? How can searching for life on other worlds tell us? And how might science and religion, and the tense area between them, respond to a prospective future discovery?
Ariel Anbar, who is Professor of Earth and Space Exploration and of Molecular Sciences at Arizona State University, as well as a Distinguished Sustainability Scholar in the Global Institute of Sustainability, explored these questions at in an online event with Valley Beit Midrash.
(This post is part of Sinai and Synapses’ project Scientists in Synagogues, a grass-roots program to offer Jews opportunities to explore the most interesting and pressing questions surrounding Judaism and science. This was an online adult education event co-hosted by Valley Beit Midrash, a recently awarded Scientists in Synagogues organization, and Congregation Or Tizon).Read Transcript
Shmuly Yanklowitz: Thank you for joining us for the launch of our Science and Judaism series. We’re very very excited, so thank you for joining us. And we just feel that Judaism is so vast and so beautiful and so complex, and science is so vast and beautiful and complex, and how amazing would it be if they were in dialogue with each other. And so we’re fortunate to be a part of this program with Sinai and Synapses, Scientists and Synagogues, and to experiment with moving this forward in a serious way, to bring in new voices and new ideas and new synergies. And so I’m thrilled that my colleague and friend Rabbi Geoffrey Mitelman, the head of Sinai and Synapses, is here, so he can hear a few minutes about the vision of the program, since today is our kickoff. So Rabbi Mitelman, please.
Geoff Mitelman: Thank you Rabbi Yanklowitz. It’s nice to see you all and and meet you all. I’ve heard such wonderful things about Valley Beit Midrash, and thrilled to be here. And I know our Professor Anbar because he was part of Scientists and Synagogues in the first iteration which was launched in 2016. So as Rabbi Yanklowitz mentioned, Scientists in Synagogues is a project of our organization Sinai and Synapses, which bridges the worlds of religion and science. One thing that we really emphasize is that the biggest questions that we face in this world are not religious and they’re not scientific, they’re human questions. And we need wisdom from as many sources as we can on all of these big questions that we’re grappling with, ranging from “Are we alone in the universe?” to questions of climate change, to the ethics of genetic engineering, to political psychology – there are so many different kinds of conversations and topics where we need wisdom from both religion and science.
And so this project that Valley Beit Midrash is part of, Scientists in Synagogues, is actually a national initiative. There are 12 communities in this round from all across North America, ranging from Phoenix and one in El Paso, to one in New York to one in New Jersey, Virginia, suburban Chicago, all over North America, and in fact now 34 synagogues have been part of this project. You can see all of the work that we’re doing at sinaiandsynapses.org, I’ll send the link here, to be able to find out about the work that all of these incredible communities are doing, and you’ll be able to see the work that we’re doing.
I actually got an email earlier today, of somebody saying, “I want to be here from Valley Beit Midrash, but I can’t make it, is it going to be recorded?” And I said “Absolutely.” So the work that you all are doing, and exploring these kinds of questions and elevating the public discourse, is so crucial. So thank you to AJ, to Rabbi Yanklowitz, to Professor Anbar, to everybody at Valley Beit Midrash, for helping think about these questions around science and judaism and being part of this incredible national initiative.
Shmuly Yanklowitz: Thank you so much, and I’m thrilled to share we already have about five or six of these sessions set up – some are 60 minutes, some are 90 minutes – and also some interviews coming up that are shorter in length as well. Put it down on your calendar – our next one, January 21, is Evgenya Shkolnik, who was already mentioned, Evgenya Shkolnik will be talking as well, and then Professor Michelle Lani Shiota on February 9th, and many others to come. Our plan today is to have a slideshow presentation for about an hour, 60 minutes, and then we’ll open up the floor for about 25 minutes of questions. Feel free to chat on the side, your thoughts and questions, as always, in the meantime. And then we’ll be able to unmute folks for the Q&A after.
So Professor Ariel Anbar is a scientist and educator exploring Earth’s past and future as an inhabited world and the prospects for life beyond. He directed ASU’s astrobiology program from 2008 to 2016. He also directs ASU’s Center for Education through Exploration, which is reinventing digital learning around curiosity, exploration and discovery. A graduate of Harvard and Caltech, Professor Anbar has been recognized for both his research and education excellence in awards from multiple national and international organizations. He’s now a President’s professor and ASU’s scholar of earth and science exploration and school of molecular sciences. Professor Anbar, thank you for kicking off our series and for being with us here today.
Ariel Anbar: Thanks very much, it’s an honor and a thrill to be asked to do this. It’s great to do this again with with Rabbi Mitelman, and it’s just an honor to be here, and it’s nice to see so many familiar faces. At the outset, I thought we’d be a little interactive, because most of this – until we get to the Q&A later – is going to be a a presentation, but we have a poll that we’ve prepared that I think I can actually distribute. Let’s see if we can make this work. I want to know before we even get started – what’s your reaction to this question: are we alone in the universe? “Yes,” “No,” or “Not sure.” I’m curious to see if this changes at all by the time the talk is over. […]
All right, so i’m going to share my screen here, so that we can actually get started. Looks like the poll leveled off and we have the results. All right, so most of you think there that we are not alone – that’s about what I would have expected, so that’s a pretty typical response. So I’m curious to know if that’s going to change by the time we’re all done with this. Let me just change this a little bit here. I’m very curious to know, all right.
So what I’m gonna do here is talk to you mostly about the scientific search for life in other worlds, but also its intersection with – I’m going to frame I with its intersection with certain religious questions and concerns, and particularly some Jewish thoughts. I may not have any answers in the end to any of this, but hopefully this will at least stimulate your thinking and fire your curiosity about this topic of searching for life in the universe, and its intersection with some of the things that we care about in our spiritual and non-scientific lives. I’m a scientist, so I apologize at the outset, I’m going to try to keep the science from being too technical. I will throw an equation at you at one point, but trust me, I’ll be as gentle as I can with it. So iIll try to not be too technical there. And not being a rabbi, I’ll try to keep the religious thoughts and connections from being too ridiculous or incompetent. I hope that the rabbis on the call will forgive me if I go astray or get something wrong. So we’ve done a little poll, and why don’t we move forward here.
Now, when we talk about the intersection of this “are we alone?” question with religion, and talk about reason or religion, there’s a tendency to right away think about the tensions between religion and science around the questions of Biblical literalism, scientific evidence versus literal interpretation of the Bible. And I just want to say at the outset here, that’s not our concern here today. Here’s how personally I deal with this kind of tension, which which does come up – and I will allude to it a little bit later, but we’re really not going to deal with it centrally here – you know, Maimonides dealt with this, you know, almost a thousand years ago, in “Guide for the Perplexed,” which is really written for people, you know, it’s really interesting to read through that, it’s written for people kind of like us, right. People who are in the rational world but also have a religious life and are trying to understand how to reconcile the two. And he has this very nice passage where he’s discussing the creation story in Genesis, and he writes that “He,” referring to God, “Described those profound truths, which His Divine Wisdom found it necessary to communicate to us in allegorical, figurative, and metaphorical language,” right.
As I understand, the Rambam’s take on the tension between science and religion when it comes to Biblical literalism is that whenever they are in tension, whenever there is conflict, one needs to look at the literal Bible and reinterpret it as allegory, as figurative language, as metaphor. And so I kind of figure if that’s good enough for the Rambam, it’s good enough for us. And that takes care of a great many of the sort of controversies that people like to talk about between science and religion. I don’t think that they’re fundamentally nearly in tension as much as the conventional wisdom would have us believe.
So the religious sort of implications and connections of the search for life in the universe that I want to talk about really more have to do with motivations, and with meaning, right. So before we talk about the science, we really probably want to talk a little bit about: “Why do we search for life in the universe at all? What’s our motivation? What’s our interest in this?” You know, we’re going to focus on the science before this talk is out, but science is a human endeavor. We do scientific investigations for very human reasons. Science drives us all as scholars to try to agree on the what of the universe, but the why questions are very human questions that are bound up in our human emotions, our needs, our desires, as much as our reason.
And so not surprisingly, when you think about it, right, the search for life in the universe, this question of “Are we alone?” is really a question that’s rooted in our human psychology, right, before we had science in its modern form. We still ask this question “Are we alone?” in various ways, in various contexts, and we sought to answer it from all sorts of traditions. And we asked it because we aren’t dispassionate about the answer, right. There’s an answer that we kind of tend to want, at least most of us, because we are social creatures, right. We ask “Are we alone in the universe?” because we want the answer to be no. And I think that’s very important for us as scientists to realize.
And we see this in all faith traditions, right. So I’ve just put some quotes here, right. The Dalai Lama right it says “Without love, we could not survive. Human beings are social creatures, and a concern for each other is the very basis of our life together,” right. So are we alone? Well, no, we can’t be alone without – if we were alone, we couldn’t even define what we are as human.
Karl Popper, not a not a religious person at all, but a philosopher of science who was very humanistic in his thinking about what science is, wrote: “We’re social creatures to the inmost center of our being. The notion that one can begin anything at all from scratch, free from the past or unindebted to others could not conceivably be more wrong,” right.
So in all sorts of traditions, right, anything, everything that we do, our sense of meaning, our sense of purpose, they all come at least in part and very often in very large parts, and often centrally, from our understanding that none of us is alone. In our Jewish tradition of course, leaving aside philosophy and just going into practice, which reflects philosophy to some extent, we have the whole concept of the Minyan, right. There are certain things that one cannot do in Jewish religious life unless one is part of a community, that one cannot do alone. And Maimonides, Rambam, again, quoting from him, “A person must join himself with the community, and should not pray by himself so long as he is able to pray with the community.” We cannot fulfill all the mitzvot alone. When we move to a new place one of our first obligations is to find a Jewish community, right.
So Judaism is very bound up, has very much, deep in its core, this notion that being alone is problematic. We don’t want to be alone, we don’t want to be alone as individuals. And I think that translates to our thinking about our place as a species in the larger universe. And we see this also in our most ancient texts about creation. Let’s go to Bereshit – so go to chapter 2. “The Lord said it is not good for man to be alone; I will make a fitting helper for him,” right. So this is deep, this is everywhere. It’s deep in the Jewish tradition, it’s, I suspect, universal in all cultures and traditions, this notion that being alone is a problem, this notion that we do not want to be alone, we want to be part of a community in some way, some form, some fashion.
So it’s really very natural for human beings. It’s deeply instinctual for us to wonder if humans are alone in the vastness of space, and to seek answers by looking out into the void. And scientists are not immune to this desire.
The rabbi Carl Sagan – a secular rabbi of sorts, born a Jew – has this wonderful quote: “The universe is a pretty big place. If it’s just us, it seems like an awful waste of space.” Well this is a very value-laden statement, right. This is a statement that walks up to but doesn’t quite say “I don’t want us to be alone, I want there to be community out there somehow, I want us to be part of something more.” It doesn’t say it explicitly, but you can kind of read the latent meaning into a statement like that.
And so we want to believe. Those – most of you are old enough to remember, I think all of you are old enough to remember –The X-Files, right. So “I want to believe,” we want to believe, we want to believe in all sorts of things. And when it comes to looking for life in the universe, we want to believe that there’s life out there other than us. And we see it all over our popular culture, right. Popular culture is full of aliens of all sorts, mostly friendly, some not, but irrespective of that, if you look at most of science fiction, it’s rare – it’s there, but it’s rare to find science fiction that does not involve alien life somehow, that doesn’t grapple in one way or another, and isn’t driven in one way or another, by this deep yearning to ask this question “Are we alone?”, and to lean towards the answers, which say “No, we’re probably not.”
So that’s all well and good, but we have to be careful. If we’re going to engage in the search for life of the universe as a science, then we have to be very careful not to let our desires cloud our view, right. We don’t want to be alone. There’s a great desire to discover life in the universe. I see this in my many scientific colleagues who are drawn to this field of science. You can see that they feel emotionally that it would be amazing to discover that there’s life elsewhere. And when you kind of push them as well – “Well, what if we don’t discover it?” – there’s kind of a disappointment there.
So we need to be cautious, right. We need to be cautious, because we don’t want the scientific search for life of the universe to become a sort of a search for the Holy Grail, a sort of a treasure hunt, right, where there’s a right answer, the answer that we want, and a wrong answer, the answer that we don’t want. Because we know from human psychology, and we know from the history of science, that once we start letting our emotions get so deeply immersed in the things that we’re researching, that we tend to go wrong. And we know this for many walks of science, but we know it in particular from previous astronomical studies that tried to look for evidence of life elsewhere. The most notable would be the research into Mars 100 years ago. So Mars has fascinated astronomers and non-astronomers on Earth for many, many – for centuries, for millennia, in simple ways. And scientists, you know, modern astronomers, since the dawn of modern astronomy – and in the late 1800s and early 1900s, early telescopes were aimed at Mars.
Percival Lowell, in particular, a very famous astronomer of the day who did a lot of work here in Arizona, aimed a telecope at Mars, and he, like many others, saw what you see here in the middle of the screen, or interpreted what they saw as what you see in the middle of the screen here. These vast networks of what were interpreted as canals on Mars, these straight lines and intersections and junctions, that could only be explained, the only rational hypothesis that could be come up with, was that this was evidence of some advanced civilization on Mars. And you see here in New York Times, August 30, 1907: “‘Mars Inhabited,’ Says Professor Lowell, declares the planet to be an abode of intelligent constructive life.”
So I don’t know if this was fake news, but it definitely was incorrect news. What Mars really looks like is there on the left – those are Hubble Space Telescope images of Mars. And what Lowell and others were seeing was the result of atmospheric distortion, plus a lot of wishful thinking. They saw what they wanted to see, because there was this romantic desire to believe in alien life elsewhere. And so they fooled themselves. And it’s not the only example in science of people fooling themselves, of seeing what they want to see, but it’s perhaps one of the most spectacular and certainly directly relevant to the question of searching for life elsewhere in the universe.
So for many decades, this notion that Mars must be inhabited, and inhabited by intelligence rivaling our own, and perhaps a civilization exceeding our own, was a very common one in the culture, because this is what scientists were saying for a while. So Richard Feynman, who said many great, pithy things about scientists and science – Feynman was a physicist, a Nobel Laureate physicist, at Caltech. He had this nice line: “The first principle is that you must not fool yourself, and you are the easiest person to fool.”
So as scientists, when we look for life in the universe, we want to not just turn this into a quest for life – it’s not a search for a Holy Grail – we want to frame it as a scientific investigation, because that helps us create a discipline around around the whole examination that that shields us a little bit from our desires. So we have a scientific field that is organized around the search for life in the universe, we call it astrobiology, the science of astrobiology, a combination of astronomy and biology. I should add I’m neither an astronomer nor a biologist, I’m a geologist. The word geology doesn’t appear anywhere here in the phrase “astro,” or the word “astrobiology,” but as it turns out, probably about half of the people who study this field are geologists, because if you want to understand the prospects for there being inhabited worlds elsewhere, you need to understand how this inhabited world works, and that’s the province of the geosciences. So astrobiology brings together astronomers and biologists as well as geoscientists and others around this central thesis, or this central statement: “Astrobiology is the study of the origin, evolution, distribution and future of life in the universe,” whatever it may be. So there’s certainly a bias towards thinking that we are not alone, that there are other life in the universe. That’s a hypothesis that we’re exploring – I’ll get to that a little bit more in a minute.
But it’s quite possible that it turns out that there isn’t life elsewhere in the universe, or that there is, but it’s extremely rare. When you frame the search for life in the universe this way, that it’s the study of the origin, evolution, distribution and future of life in the universe, implicitly whatever it may be, then it doesn’t really matter whether the universe is teeming with a Galactic Federation that we’re on the verge of joining, or is a sterile, empty universe except for us. Either way is equally fascinating as a subject of scientific inquiry. Either way, we want to understand why it is the way it is. We’re still in the exploring “what it is” stage, but that’s the first step towards then asking a deeper question about “Why is the distribution of life in the universe what it is?”, whatever it is.
So that’s the science of astrobiology, that’s taking this “Are we alone?” question, which tends to turn into a quest, into a true science, where whatever you find is equally interesting, valid and important. And when you frame the science of astrobiology this way, it’s really a continuation of a deepening of a very old trend in modern science. It really goes back to the dawn of modern science.
So as many of you know, the conception of the universe used to have the Earth at the center, the so-called Ptolemaic model of the universe named after Ptolemy, an exceptional genius astronomer of the Second Century. He developed a very elaborate model to explain the motions of the stars and the planets in the sky that was a model that had Earth at the center. It’s called the Geocentric view of the universe. The Earth is at the center of everything, everything revolves around Earth – in the Ptolemaic vision of the universe, the Geocentric universe.
And it was around the time of the birth of science in its modern form, of the experimental, observational testing form of science, that Corpernicus, in the 16th century, developed the heliocentric view of the universe. And this was an alternative model that similarly tried to explain the motions of all the stars and planets, everything you see in the sky, but in terms of a sun-centered universe, right – the sun at the center, the planets revolving around the sun. And then in this model, to explain what we see in the sky, the Earth ends up being the third planet from the sun. And to a modern sense, it’s kind of – “Well yeah, this is much simpler, right”. They have the sun at the center and things revolving around it.
But that certainly wasn’t the case to the thinkers of Corpernicus’s time, and before, and even for some time after, because the Earth-centered view is in many ways much simpler. In order to accommodate it, though, you have to create all sorts of complexities. And you can see it a little bit here in this geocentric view. You see these planets have making these little what are called epicycles, these little circles in their orbits. Because to really explain in detail the things that you see in the sky in terms of a geocentric view, you need a pretty complicated model. It looks simple to put Earth in the middle, but it becomes complicated to explain everything else. The sun-centered version, the sun- centered model, is in many ways simpler. But in a big sense, it’s actually kind of more complex, because you’ve got to wrap your brain around the idea of the earth not being at the center of things. You know, you look outside, it sure looks like the Earth doesn’t move, and everything moves around us. So that seems simpler to many people at the time.
So Corpernicus’s view did not win out right away. And in fact, in its earliest forums, Corpernicus’s model wasn’t actually as good as Ptolemy’s model in predicting the motions of things in the sky, because Ptolemy’s model had a lot of complexity and nuance in order to cope with all the details, whereas Corpernicus’s model was still new.
So this was a radical innovation, and not one that was accepted right away, but it was a view that came out from experimental observation and held up much better to future experimental observation by folks like Galileo – which got Galileo in trouble with the Church, as most of you are probably aware. One of the defining battles around the time of the birth of the modern scientific era, and in many ways, this battle, this tension between science and religion, is often framed in terms of this debate between Galileo, who aimed his telescope and saw evidence in support of the Copernican worldview, and the Church of the 17th century, which said “No,” which still stuck to a heliocentric view of things.
And this is often framed as a debate of Biblical literalism versus scientific observation. It’s often framed in terms that I said at the outset, you know, we weren’t going to talk about too much, because the Rambam kind of said, “Well, look, when science and religion are in conflict, you need to interpret the religious – you need to interpret the Bible a little bit allegorically.” But this, really – although this is often framed as a debate between scientific fact and Biblical literalism, I don’t think it really is that. I think this really was a debate about meaning. This is really a debate about “What is humanity’s place in the cosmos?” because the geocentric view, the view that has the Earth at the center, puts humanity at the center. And when you demote Earth to the third rock from the sun, you demote humanity as well. You move us out from the center of things.
And what emerged from that view, and what partly led to that view, is a philosophical stance that early scientists took, which has held up very powerfully in physics and chemistry, which is that the things that we experience on Earth, the things that we observe, are typical, right, that we aren’t privileged observers. The things that we see are not different from the things that other people might see elsewhere. We are not exceptional or unique, we are typical. And moving the earth from the center to the third rock from the sun, right, is sort of emblematic of that. And I think this tension between science and religion really has much more to do with that, with how we see humanity’s place in creation, in the universe – if you don’t believe in a creator, then any of the literalism.
I think that’s true of evolution also, where we have arguments between creationists and evolutionists about, “Well, the Bible says this, and Darwin says that.” I don’t think it’s really about that, right. I think it’s really about humanity, of our desire not to have humanity demoted from the center of things. And so it’s kind of funny, really, when you think about it, right. On the one hand, we have this deep-seated desire to not be alone, to be part of a community, but we also have a deep-seated desire to be special, to be unique in some way. You know, it’s like we’re kids and we want to have siblings, we want to be part of a family, but we want to be the special kid, right.
So I think this is part of the tension that religion and science have dealt with, science usually pulling us towards being typical, being not exceptional, religion, very often –religious world views trying to pull us, or emphasize, or find, or discover, what’s special and unique and important about us as humans, and each of us humans as individuals. That’s, I think, the fundamental tension, really. And it’s not a tension that is irrevocable, it’s a tension, I think, that can be overcome in many ways when you understand it for what it is, when you understand it’s not about the debate between scientific fact and words that were written long ago by people who simply didn’t have that level of observation of of the universe.
So to come back to the search for life, the science of astrobiology, what are we exploring, then – so I gave you this vision of the history of science, moving from the Ptolemaic to the Copernican worldview, from the Earth-centered view to the sun-centered view, this notion that we are typical. So in physics and chemistry and astronomy, that’s certainly been true. The science of astrobiology is essentially exploring the following hypothesis: that the Copernican Revolution applies to biology. That in terms of biology, we are also typical in the universe, right. Most of you said that you think that we’re not alone in the universe, and that’s because most of us have internalized this notion that the things we observe on earth are probably not unique. I mean, details are unique, each of us is a unique snowflake, but the things that we observe on earth are things that could happen elsewhere. In physics, in chemistry, astronomy, that’s certainly true. We’ve internalized the notion that it probably applies to biology, which is why the current thinking is that yeah this Copernican idea, this notion that we’re not privileged observers here, applies to biology as well. And hence, if it happened here, it should happen elsewhere. And that’s a fine hypothesis, I bet it’s right, but it needs to be explored. We don’t really know if it’s true, because right now we only have one example of life in the universe, and that’s here.
So what I’m going to do now, in the remaining next 20 minutes or so, is walk through some of the science. I’m going to give you a whirlwind tour of the science of astrobiology, I’m going to give you a sense of what we know and don’t know, and how we try to organize our thinking.
There’s a few ways to go about this. One thing to realize is that there is this kind of tension in these kind of discussions and presentations as far as what kind of life we’re talking about – on the right, we have microbial life, on the left, we have alien intelligence. We scientists tend to get just as excited in many ways about microbial life as about alien intelligence, because right now we don’t know about evidence of any life anywhere other than this world. And so we focus a lot on the origin of life, and the possibility there could be life of any sort elsewhere. We also figure, for reasons we’ll get into later, that microbial life is probably more common than advanced intelligence, so it should be easier to find in some ways.
But when we ask the question “Are we alone?” as people in the popular culture, which we are – even those of us who are scientists we also live immersed in the popular culture – we’re really thinking about intelligence out there, right. You know, I’ve done this survey sometimes with kids in my classes – “Do you think that we’ve already discovered microbes elsewhere?” And a lot of kids think we have, that, “Oh yeah, we know there’s microbes.” They’re still fascinated with the “Are we alone?” question, because when they ask “Are we alone?” they’re thinking about aliens, they’re not thinking about microbes. And that they know that we don’t know if there’s aliens out there.
So we’re going to focus this presentation around this question of alien intelligence, not just microbial life. And I’m going to warn you at the outset, I’m going to throw just a little bit of math at you, because – you know, this is a sophisticated, Jewish audience, so I figure I can do this. We’re not gonna solve any equations, I just want to throw one equation at you, which, if you’re familiar with this topic, then you’ve heard of this before. It’s barely an equation. It looks a little intimidating, but it’s barely an equation. It’s really a way of organizing the things we don’t understand.
So it’s called the Drake Equation. It’s named after a famous astronomer named Frank Drake and he, back in the early 60s, came up with this way of thinking about the search for intelligent life in the universe, that the number of civilizations that we could communicate with, which we’ll call N, is equal to the product of a bunch of things, each of which is actually pretty simple to understand. This is a kind of a stacked probability kind of a thing.
So the first term of the Drake Equation, R*, this is the rates of formation of stars that could host Earth-like planets. It could be the universe, could be the galaxy, depends on what space you’re talking about. We’ll focus on the galaxy here, right. So how frequently do stars that could host Earth-like planets form? That’s the first term of the Drake Equation.
The second term is the fraction of those stars that have planets, right. It could be that every star has a planet, it could be that no stars have planets except for ours, or it’s somewhere in between. It’s a very simple concept.
Then, for those stars that have planets – “What’s the number of Earth-like planets per solar system?” You know, is an Earth-like planet a unique thing to our solar system, is there only one place that’s happened, or is it a common thing that happens all over the place? And then the fraction of Earth-like planets on which life begins, because we’re going to define what Earth-like means in a minute, but Earth-like doesn’t necessarily mean it has life.
So once you’ve sort of gotten a sense of how common Earth-like planets might be, well, on what fraction of those does life begin? Again, we don’t know the answer to this question, we’ll talk about the uncertainties in a minute.
And then of the planets on which life begins, what’s the fraction of those on which intelligent life evolves? And then just because you have intelligence doesn’t mean you have radio, telescopes and other kinds of means of communicating across the vastness of space. Dolphins are intelligent, but they have flippers. They don’t build radio, telescopes, or rockets, right. So then you have fc , the fraction of planets with intelligence and a detectable civilization.
And then finally, the last term in the Drake Equation is the average lifespan of the detectable civilization. How long does a sophisticated civilization survive? It turns out that this is the most uncertain part of the whole thing, and the whole thing swings on the value of L, right. So you know, if you don’t like math, just ignore the math. But it should be kind of intuitively sensible to say that, well, the number of civilizations out there with which we could communicate, the number of advanced aliens that could be out there right now, would depend on these things, right: how many stars there are that could host Earth-like planets, the fraction of those stars that actually have planets, the number of Earth-like planets per solar system, the fraction of Earth-like planets where life begins, the fraction of those on which intelligence evolves, the fraction of planets with intelligence that have a detectable civilization, and the average lifespan of detectable civilizations. […] It’s like this stacked probability thing.
So we’re going to walk through now each of these terms very quickly – maybe not so quickly, but we’re not going to take too much time or go too much depth – to give you a sense of what we do and do not know. Because it turns out that this equation, this is organizing the things that in 1961 we didn’t understand, now we’ve made a lot of progress, but there’s still a lot here that we don’t understand.
And so this is an equation that organizes our uncertainties, and as it turns out, as you go from the top to the bottom, we move from things that we actually know pretty well to things that are really uncertain. So it’s a very nice kind of way to frame the search for life in the universe, and this “Are we alone?” question.
So “the rate of formation of stars that could host Earth-like planets. So we live in a vast universe. This is a picture from the Hubble Deep Field. Everything you see here in this picture is a galaxy. We think there are something like 100 billion galaxies in the known universe, just from a little patch of sky. Take a quarter and hold it up and look through a quarter, and look at that for a long, long time, and you’ll get this image. That’s essentially what the Hubble Space Telescope did when they did this Hubble Deep Field image. And in that little quarter of space, there’s this immensity of galaxies. And overall, we think there’s some 100 billion galaxies in the known universe. We live in one of those galaxies – we live in the Milky Way galaxy, which we understand fairly well. It’s not a particularly exceptional galaxy, from anything we can tell. It’s a pretty typical galaxy of its type. It’s about 100,000 light-years across, which means it takes light a 100,000 years to get from one side to the other. And it contains around 100 billion stars. So when Carl Sagan says, “You know, it would be kind of a waste of space if we’re alone” – you know, 100 billion galaxies, each containing 100 billion stars, that’s a lot of opportunity, right. So it is kind of mind-boggling to think that we are alone, if indeed we are alone.
But in terms of R∗, we understand stars in the universe, we understand how stars form, we understand this all fairly well. And so we think that we have a pretty good handle on this R∗ term. We think that roughly five to 10 stars per year that could host Earth-like planets are formed in our galaxy.
So this is one that we can check. We got this one. It’s the one that we’ve had for a while. So let’s talk about the fraction of those stars that have planets. So this brings us to an area of research that in the past 20 years has exploded. It went from science fiction to science reality, very strongly because of this particular telescope. This is the Kepler Space Telescope. This is a mission that was launched in the last decade, specifically with the goal of detecting planets orbiting other stars using what’s called the transit method, which you see in the upper right here. You’re seeing brightness over time as a planet goes across the dips of its star. And so what the Kepler Mission did is to look at thousands upon thousands of stars, looking for little dips in brightness. And from those data plus statistical models, the goal was to figure out “What’s the fraction of stars that have planets?” Not by theory, but b “Let’s go look for planets, let’s go look for evidence that there are planets out there.”
And so the Kepler Telescope has finished up its mission. It, on its own, it has discovered thousands of planets that our current count for planets in general – and I have to update this every time I give this talk, because this number changes – goes up steadily over time. We’ve now discovered over 5,600 planets, 4,300 of them of which are confirmed discoveries, meaning there have been follow-up observations that confirm that the discovery really is real, more than one observation to confirm it. And as a consequence of this, we’re now pretty convinced that most stars have planets. The fraction of stars that can harbor Earth-like worlds around them, that have planets – it’s about one, it’s about all of them. Planets are really common. We didn’t know this when I was a grad student 30 years ago, 25 years ago. Many of them are very weird planets, like this one here. Many of them are gas giants that are really close to their stars, right. In our solar system, the gas giants are really far away, but some of these are gas giants that are as close as, or even closer, than Mercury is to their sun – planets we didn’t actually predict could exist, but they’re out there.
And it turns out that those kind of planets are easy to find for a bunch of reasons. So we found a lot of them.
So the fraction of stars that have planets is close to 1, so we can check that one off. 20 years ago, we didn’t know that, now that’s known. The next frontier – which is pretty active, but is reaching some kind of resolution now – is the number of Earth-like planets per solar system. Because what we’re looking for are not gas giants, if we’re talking about searching for life in the universe. We’re looking for planets like us.
So this is a picture of us. This is a family portrait. You are in this photograph, taken by the Cassini Orbiter around Saturn that turned its camera back to look at Earth. That little blue dot is you, is all of us. That’s Earth. So what we’re looking for are Earth-like planets.
So what’s the abundance of Earth-like planets per solar system? If solar systems are common, how often do solar systems have an Earth-like planet? Well, what do you mean by earth-like? We could go on and on about that, but broadly, the way astronomers and astrobiologists think about it is [that] an Earth-like planet is a planet that is a rocky world like ours, not a gas giant, that’s at the right distance from its star to have liquid water at the surface, that could have oceans at the surface like we do. That makes it Earth-like. Now, we could argue about whether that’s too constrictive or not constrictive enough, but that’s kind of a working definition. That’s going to be different in different solar systems, because for a hotter star that means the planets have to be further out. For a cooler star, that means the planets have to be closer in.
So we have this concept called the “habitable zone.” So what we’re looking for are rocky planets in the habitable zones around their stars. And it turns out that that’s not rare. And that’s what’s emerged in last few years from the Kepler mission. A paper that was published, or made open – submitted for publication and made open just a couple months ago – gives the first accounting of the number of Earth-like planets for solar system coming out of the Kepler mission, as well as integrating some other data. And it looks like it’s around half. There are some errors around it, but it looks like every other solar system out there has got an Earth-like planet, or a planet that could be Earth-like, let’s put it that way. We don’t know if it has water, but we know it’s a planet that is at the right distance from its star, that if there is water on that planet, it could have liquid oceans. And it’s a planet that’s big enough that has enough gravity to hold its water, and not so big that it becomes a gas giant.
About half of solar systems have planets like that. Doesn’t mean they have life, doesn’t even mean they have water, just means they could have water, and arguably could be habitable, if all you care about is water. So this is one that we can give a check to now also, and that’s just in the last few years. So this is like, you know, exciting frontier science.
So now we get to the ones that are more contentious, less clear, because they depend on making observations that we can only make on Earth. So the fraction of Earth-like planets on which life begins, how easy is it for life to get started? I have colleagues who think that – and I think they may well be right – that the emergence of life may be an inevitable planetary process. If you’ve got the right conditions, it’s just going to happen. It just takes some time – it’ll happen. But we don’t know if that’s true. Maybe it’s a freak thing, maybe it’s a 1 in 100 billion times 1 in 100 billion thing that only happened here. We don’t know. What we can do is look at the history of life on Earth and try to infer some things.
So this is a picture of a rock – I’m a geologist so I’m going to show you some pictures of rocks here.This is a picture of a rock that’s about 3.5 billion years old. Geologists use the abbreviation ga for billions of years. When you see ga on the right, that means billions of years ago – billions of years old. So this is a rock that’s of a type that’s called a stromatolite from approximately 3.5 billion years ago, from a place in western Australia that is cheekily called “North Pole.” It’s called North Pole because it’s really, really hot. So Australians have a good sense of humor, and they call it North Pole. So this is about 3.5 billion years old. The Earth, we are pretty convinced from lots of lines of evidence, is about 4.6 billion years old. So this particular rock is 3.5 billion years old. You can find evidence of life on earth from as early as about 3.8 billion years. It’s debated, but there are signs of life that I think are actually pretty pretty interesting and convincing, starting around 3.8 billion years ago, so it seems that life maybe gets going pretty quickly on Earth.
So that’s one thing we can do, is we can look to ancient Earth to try to get evidence for how quickly life got going here. The other thing we can do is we can look in our solar system, right. If we found evidence of what we like to call a second Genesis, if we found evidence of life elsewhere in our own solar system that we could convince ourselves arose separately from us, an independent origin of life that happened twice in one solar system, well, then the odds of life being common are are pretty good, right. It happened twice in one Solar System, it probably happens inevitably in many, many places. So that’s what’s driving, now, a lot of the search for life in our own solar system.
So here are the planets in our solar system. We have a lot of places we could look, there’s been, as you are probably aware, lots of effort to explore Mars. This is a panorama from the Curiosity rover, which is squirreling around Mars right now. Most of these missions have not had as their explicit goal to look for evidence of life, but they’ve been looking for evidence of water, and past water, and evidence that Mars in its past was a habitable environment. And we have good reason to think from these investigations that in the past, Mars was, but today, probably not, but in the past it might have been. And so there’s a lot of interest in further exploration to Mars to see if we could find evidence of ancient life there.
Now what i’m going to do here is try to show a little movie, because there’s a little trailer here from the next Mars mission. You might be aware that there’s a mission on its way to Mars right now that was launched last summer, the Mars 2020 mission, which has another rover, which lands in February. So it lands in just a little over a month. So let’s see if we can make this movie play, and hopefully it comes through for you guys.
If you catch that, February 18th this thing lands. Now this is a very cool mission, this is NASA’s first mission since the late 1970’s that has looking for life as an explicit goal. Many of the instruments here are designed not to look for current life, but to look for evidence of fossil life. I’m not going to go through all these these instruments, because frankly I don’t understand most of them, but this is a mission, it’s a rover that is following up on the previous rovers, in order to look for evidence of past life on Mars. And the most exciting thing about it for many of us is it’s actually going to drill and store samples in a little canister that is designed to be picked up by a future mission that is still being designed, and bring those samples back to Earth, where we can interrogate them in the lab much more carefully than we can do on a remote rover.
And so what’s driving this search for evidence of life on Mars with the undercurrents, right, the implication that, well, if we could convince ourselves that there was life on Mars in the past that originated independently of life on earth, then the odds of life in the universe go way up. Then this fl term is probably close to 1. It’s likely that probably any planet that can host life, and probably can originate life. So that’s one area of investigation in our solar system around this theme.
The other is driven by discoveries in the 1970s that life exists, even in the cold, deep, dark ocean near these hydrothermal vents, these hot areas where magma from the earth’s interior interacts with water and creates superheated plumes of material, hot water and chemical environments in which microbes, of various sorts, can thrive, and other organisms can live off of that. So this is life that is cut off from sunlight. It doesn’t have anything to do with photosynthesis or the kind of biology that we’re normally used to – metabolisms are normally used to. And so conditions like that might exist elsewhere in the solar system. Jupiter’s moon Europa, we know, has a subsurface ocean that, at the base of it, could have the same kind of processes. And so there’s a lot of interest in the possibility that there could be life beneath the surface of Europa. And there’s a mission planned called the Europa Clipper Mission that will be an orbiter that will be designed to look closely to get a better idea of what might be possible there. It won’t be directly looking for evidence of life, but it’ll be understanding the context.
And then finally there’s this little moon of Saturn called Enceladus. This teeny, teeny, tiny moon that the Cassini mission discovered has jets spewing out of it – jets of icy water. They’re coming from a liquid water subsurface ocean, most likely. And the analyses of the plumes of material flowing out of there are that these are plumes of water, there it must be a source of energy to to melt the ice, to make water, there almost certainly are reactions going on like that happen at the bottom of the Earth’s oceans, between water and rock, that create conditions conducive to life. There’s what’s called reduced nitrogen in these plumes, which is necessary for life, and organic molecules have been detected in them, which are building blocks for life. So there’s a lot of excitement about some future mission to go and fly through those plumes and try to get a sense of whether or not there is life on Enceladus.
So this fl term question mark, we don’t really know, but I’m going to try to give you a sense of how we go about it. We look at Earth’s past, we explore the solar system to try to get a sense of whether life on some of those planets – we’re talking about elsewhere, right, Enceladus and Europa are not Earth-like, but if you have life on a planet that’s as weird as Europa, an object as weird as Europa relative to Earth, then Earth-like planets almost certainly have life, right.
So then we come to the last two terms, or not last two ,but the next two terms, fi and fc , intelligence and detectable civilizations. So one way to go about that is the search for extraterrestrial intelligence. If we found intelligent life elsewhere, then we’d start to have a pretty good handle on this, right. So radio telescopes looking for radio signals from other worlds is one way we go about trying to figure out what these numbers might be, what these probabilities might be. The other thing, again, is to look at earth’s history, to look at the rocks. And so, you know, the layers of rocks are the layers of history that are pages of time. And so we can look back in time and ask ourselves about the history of life on Earth. So here’s a fossil of one of the first animals on earth, the so-called Dickensonia from the Ediacara formation. These don’t appear until about half a billion years ago.
So on Earth, anyway, it took a long time from when life began, to when we’ve had the first multi-cellular animal-like organisms, and then, you know, real animals that walk the earth, dinosaurs and stuff like that. So they came after that, obviously. And you know, the demise of dinosaurs was not that long ago. Dinosaurs lasted for a couple hundred million years, and they ended around 65 million years ago, which is almost yesterday, geologically speaking. And then the first hominids – depends how you want to count. You know, Lucy’s a couple million years ago. Homo sapiens is much younger. But you know, a couple million years is, again, it’s yesterday geologically speaking. So the rise of the stirrings of intelligence that would lead to us is a very recent phenomenon on Earth, after life had existed on earth for a long, long time. And so technological civilization, of course, is after that, is at the very tail end of this.
So it looks like [if] we look at Earth’s history, it looks life gets going pretty quickly. It looks like to order to originate life is not that hard, if you’re going to infer from Earth’s history. And that life persists tenaciously, but that tool-using intelligence like us that could build radio telescopes and communicate across the cosmos, emerges very late if it emerges at all. But it takes billions of years before that happens. That’s what one would infer from Earth.
So one might infer from Earth that while the origin of life is easy, the fraction of planets on which intelligence evolves is small – that’s a rare thing. But on the other hand, once that happens, you get to communicating civilizations pretty quickly, right. Because the gap between us, the gap between the origin of life, and the rise of the first hominids – that was very long, but from the first hominids to us, it’s actually pretty fast, a couple million years. So maybe once you have intelligent life, you get communicating civilizations pretty fast. Maybe. But again, we only have the one example of us here on Earth, so unfortunately until we find evidence of life elsewhere, or develop a real theory that we believe, that can predict these things, which we’re nowhere near, we are stuck with conjecture.
And the final term is the lifespan of a civilization, right. What’s the average lifespan of a sophisticated civilization that can communicate across the cosmos? So this gets into questions of our future, which is frankly another reason I think that many of us are motivated to search for life elsewhere, because looking for life elsewhere gives us some hint of what might be our future. If we live in a galaxy filled with advanced civilizations then, and we’re typical, then we should be able to become an advanced civilization that that travels the stars and or whatnot, right. But if it’s an empty universe, an empty galaxy, then we have to ask some pretty deep questions about our future.
And we are in this realm now where we are entering an epoch that geologists now are starting to call the anthropocene, the age of humans. We are starting to have such an impact on the planet – global warming is just the beginning really, frankly, of our ability to impact the planet – that humanity is becoming essentially a geological force. Very few species in the history of life have been like that, so we’re pretty unusual, if not unique. But the prior ones that could do that did not have self-reflected conscience and will, and so in that sense we certainly are unique. We can create the planet of our choosing, we’d like to think.
So is our future going to be, you know, the end? Are we not going to last very long? Will we be unable to manage our impact on ourselves, leading to our own demise, or will we find some way to balance between our human needs and desires in the planetary system, and reach some sort of sustainable harmony? Scientists actually debate whether or not there is such a thing as a “good anthropocene.” Can any anthropocene have a good end? Some feel that it can’t, that humans are inevitably going to wreck the planet. So we don’t know, right, and that’s another reason that we search.
So are we alone? Maybe life is common… but intelligent life is rare. Maybe it’s just us. Maybe Corpernicus doesn’t apply to biology. Maybe we are exceptional and truly unique. As it turns out, even if we’re not unique, even if Corpernicus is right, even if what we see is typical – if it took billions of years to get intelligent life, if that’s a typical thing, if a planet that originates life has to hang around for billions of years before life, before intelligence emerges, and if intelligent civilizations don’t live very long, then even if our experience on earth is typical, it may be that we’re effectively alone. And the latest estimates are that, under those strict conditions, there could be as few as about 30 to 35 civilizations in the Galaxy right now that we hypothetically could communicate with. And out of 100 billion stars, having only 35 civilizations means that, in practice, we’re alone, even if our situation here is typical. That’s a possibility, depending on what “typical” really means. But it could also still be true that, in fact, we are completely unique. It could be true that the origin of life is a freak event, or the origin of intelligence is a freak event. That is incredibly unlikely, such that perhaps we are completely alone.
And now just to wrap up and bring it back a little bit to Judaism, you know, many of my colleagues, and many of us, I think, are unsettled by that prospect – the notion that we might be alone. It’s so different from the conventional wisdom right now. But you know, I think we have to ask why that makes us unsettled, right. It makes us unsettled, in a way, because it places a huge emphasis on ourselves, because if we’re alone in the universe, then it’s not just that our own future depends on how we treat this planet, it means that the future of life in the universe depends on how we treat this planet. And what we do – it’s all on us, and it’s not our choice to be in this position. It’s a choice that’s been made for us by the nature of the universe. If that’s the way it is, then we’ve been chosen – which, as Jews, should sound a little familiar – so maybe that’s actually not such a strange idea. I mean, maybe it starts to sound a little bit like tikkun olam, that we have to take care of this planet because it’s an incredibly precious place in all of creation, you know, maybe that’s the way it is.
So the search for life elsewhere, you know, until we find an intelligent species somewhere else, which may not ever happen in our lifetimes, and our children’s lifetimes, and our children’s children’s lifetimes – the search for life elsewhere should drive home to us just how special this planet is, just how special our place on this planet is. And special, potentially, in a truly cosmic sense. The rabbi Sagan said, “We are a way for the universe to know itself.” And that may in fact be true, because we may be the place where this is all happening. And the future of that is, then, all in our hands. And so if that’s the case, may that possibility renew our dedication to our own ideals of making this world all that it can be. Thank you.
Shmuly Yanklowitz: Beautiful. Professor Anbar, this is so fantastic. I feel so – I learned so much and I’m so inspired and I’m so glad we have a half hour to ask you questions. And I’m gonna take the privilege of the first. I have dozens [of questions] I could ask you, but I want to make space for others to ask their questions.
So here’s my first. I think that when we talk about religion, we oftentimes think that we’re talking about the realm of truth, as opposed to the realm of experience. So I want to ask a question, not about truth, but about experience, phenomenology if you will. And that is to say: this session mostly today has been about looking outwards, what exists outwards. And I want to ask the question that every religious tradition does, and every spiritual practice asks, which is looking inwards. And how has this work for you – if you’re comfortable answering personally – or how have you found others in your field have experienced a new type of spirituality based upon this type of study?
Now, let me go a little bit deeper on that question. One way to ask the question is “Do we see commonalities between the micro and the macro?”. That’s to say, the human body, the social dimensions of life, in relationship to the macro, of how we think of the solar system and beyond. That’s one way to ask it. The other way to ask it is: the spiritual concept of oneness, which every spiritual tradition holds in one way or another, of oneness of all life, oneness of all existence, how does zooming out, or zooming in, help you or not help you to think about that?
Ariel Anbar: Well the second one is maybe easier. So, you know, scientists are also driven by kind of a oneness, an appeal to oneness, right ,we try to develop theories that we can extrapolate elsewhere. So we have theories and ideas about what life needs, what life requires, what drives biology, and then we look for evidence of that elsewhere, right. And so there’s this deep sense, right, that whatever we discover out there, and however surprised we’re going to be – and we know we’re going to be surprised because our imaginations fail us – that we’ll be able to understand and comprehend it in terms of the laws of physics and chemistry as they are applied to what we call “life,” as we understand them here, right. I mean, that is itself a kind of – when we talk about it as scientists, we don’t talk about that as spiritual, but there is certainly a spiritual element to it if you start thinking about that using that language, right.
I think Einstein said something like, “The most remarkable thing about the universe is that it can be comprehended at all,” right. I mean, that’s when you start having these sort of metaphysical thoughts – I don’t think you can really study science as a thinking, conscious person without stumbling into these kind of metaphysical areas, right. And you have to kind of half-hang up your sciences hat when you step into them, because they’re simply realms where science can’t really guide us, but they’re there. So why is it that the whole notion that we can make observations on earth, that we can extrapolate ourselves elsewhere, that’s remarkable, right? That speaks to some kind of oneness and unity in the universe that underpins the entire thing, and underpins the scientific enterprise. Why should it be that way? I mean, that’s just an axiom of science, right, that it is that way, but if you want to get metaphysical, why should it be that way? I don’t know why it should be that way. Because of God, creator, whatever you want to phrase that.
The first question you asked, about inner versus outer, what comes to my mind when you ask the question is – and I guess Rabbi Wasserman isn’t here – so I many of you know I attend The New Shul, so Rabbi Wasserman has thought a lot about this tension between religion and science, and wrote a very nice essay a couple years ago trying to argue that the tension really, you know, shouldn’t be there, because if properly understood, both science and religion are fundamentally empirical, right. Science is dealing with the empirical “outside” of observation of the making of the universe that’s replicable, and religion takes care of the domain, or deals with the domain, of observation that we make, that’s very personal and internal that inherently can’t be replicated, right. You and I cannot have exactly the same experience of things. There are things that we will experience and feel that are different. And religion is trying to, in part, help us understand these experiences that we have that are fundamentally subjective. And I can’t do justice to his essay. But that’s kind of how I try to deal with that duality.
Shmuly Yanklowitz: Beautiful. Thank you friends, please unmute yourself if you want to jump in with a question. There’s always a little pause before someone comes in. That’s okay.
Okay, I’ll jump in, Shmuly. If you’ll bear with me, because I don’t know that I can do this sort of otherwise. In the Jerusalem Post this week, I don’t know if you saw it, there was an article or statement by Eshed, who is…
Ariel Anbar: Is this he former the retired intelligence guy who–
Yes, retired Israeli officer, current professor, Haim Eshed, about keeping all this secret because humanity isn’t ready for it yet. But he seems to have the credentials and the life experience, and I sent it out to a couple of people and it was interesting, the responses. A couple of people said yes, they definitely believe that this is true, and other people said they’d like to send some people up there to get rid of him. So I would just like to know what your take is on his credentials, and the article itself? You obviously are familiar with it.
Ariel Anbar: I only know from news accounts, so to to help others, there is a news account of a retired former Israeli – he was highly placed in Israeli military intelligence, if I’m not mistaken –, who was interviewed by a reporter and talked about how it’s known to intelligence services that there are aliens, that there are agreements and deals with them that US administrations have made, and it has been kept secret until we’re ready for it. Um, so you can probably tell by my kind of half-smile that I don’t believe…
I was going to say, I can tell (laughs).
Ariel Anbar: But yeah, by my demeanor, so my gut reaction to it is – well, severalfold. But, you know, at core, you know, our governments are not all that good at keeping secrets, especially for a long time, especially big ones. I mean, we see that over and over. So then, to me, the notion that there has been contact made, that somehow has been kept so secret that nobody knows about it, and then this older fellow blurts it out to a journalist, strikes me as not inherently – the context makes it not very credible, right. So why would he be saying this to a reporter, right? Well, if the conspiracy is so well done that nobody’s heard anything, then why is he able to pop off to a journalist during an interview, right? And if the conspiracy is so bad that that can happen then, there should be leaks all over the place that are more credible even than that – especially in the scientific community. I mean, scientists and academics are really lousy at keeping secrets. I mean, it’s just not what we do. We’re wired to make discoveries and shout about them. So you have to postulate that somehow, whatever scientists were brought into these conversations have been somehow kept very, very quiet, and that somehow this has happened without there being any evidence that the rest of the scientific community has looked at, that is the kind of replicable, useful evidence that we can chew on as scientists.
So I find hard to believe . It’s not impossible. I mean, I’ll say at the outset, it’s not impossible – there are things we don’t understand, there are now credible reports of unidentified objects that the New York Times has reported on, that U.S. military intelligence has made publicly available. There are things that we don’t know. But to leap from that to saying that there is alien intelligence, let alone the whole story that he spun, strikes me as far-fetched.
Shmuly Yanklowitz: Great. We have a question here from Sohan.
Hi Professor. I have a question about the Day of Judgment and extraterrestrial life. How do you imagine that might work, or even, actually, for that matter, like humans on other planets – if we colonize other planets, and given how how terra-centric Judaism appears to be, specifically its attachment to specific locations, physical locations on earth, like Jerusalem and everything. So I’m just wondering how would that work with a civilization, and multiple civilizations even, on the scale of like galaxies or something like that.
Ariel Anbar: Well, there’s a few questions wrapped up in there, I think. I mean, I think it is interesting to ask how will whether there’s life elsewhere or not, if humanity spreads to other worlds, how will religions evolve to cope with that, right? Will religions evolve to cope with that, will there be a need? I mean, at a very practical level there will be some sort of need right you don’t face east when you’re on Mars exactly, so in terms of ritual ritual will will somehow evolve. But you’re asking a deeper theological sort of question I think.
Shmuly Yanklowitz: Okay, let’s go to the next person here. We can circle back to such ideas. Michael?
Well, one thing I’ve worried about that you didn’t mention with different scales was kind of – I wondered about the concept of infinity, and the scale of – I mean, perhaps, you know, you hear concepts now, what was before the big bang, and possibly other universes, you go infinitely large and infinitely small. So we’re really saying is: at the scale in which we exist, is there other life? And I know this is maybe beyond what science [can find], but have a concept of different scales, and you know, as we get smaller and smaller, as we see the size of the universe, isn’t that also kind of what our place is and all that?
Ariel Anbar: So there’s what science can deal with, what science can investigate, right, which is the universe as we perceive and understand it. Once you get into sort of the metaphysics of other universes, which is at the – there are physicists, cosmologists, who try to deal with that notion. And it’s at the boundary of what I would say [are] physics and metaphysics, right, because these are ideas that we kind of dream up, and then we ask “Is there a way that our physics could actually even test the idea of there being other universes?,” right, the whole multiverse concept. And we don’t know, the jury is still out on that, right.
So at that point, science stops as we know it, right, because it’s at the level that it’s at right now, and we’re just in the realm of speculation. So could there be other universes where there is life that doesn’t interact with us in the normal way that we’re used to? Yeah, but it’s in the realm of speculation, right. It’s not going to be the problem from uh
Let me just say one more thing but the history you’ve gone through with us is a history of that skill expanding starting with “The Earth is the center” then the solar system, and we now see it on the edges again the possibility of expanding beyond our universe. I think your intuition is right and kind of comports with mine. Let me put it in slightly different terms: there are a number of, you know, at the end of the 1800s, there were a whole bunch of observations piling up in physics that kind of contradicted each other and the existing view of how the universe worked, and what the rules of physics were that kind of, you know built up and built up until Einstein came up with relativity, which started to unlock some of these things, right. And then quantum mechanics came along and provided theories and ideas that explain many of these observations that otherwise didn’t make a lot of sense, that didn’t fit together. They left us with deeper mysteries too.
But now a hundred years later, a little more than a hundred years later, we also have a pile-up building of observations that are kind of puzzling, like dark matter and dark energy, right, the universe is made up of stuff that has mass that has a gravitational effect that we see on motion of galaxies, but we don’t know what it is and it doesn’t seem to interact with light, right. If there really is a mysterious matter, right, what’s that all about? Dark energy, right, there seems to be a force pulling the universe apart, right, slowly. It’s not gonna fall apart tomorrow. So these are weird things, right, we can’t understand. And so I think we are kind of building up a set of weird, contradictory observations that some future theory is going to blow our minds about. And maybe it will have implications of multiverses and whatnot..
Shmuly Yanklowitz: Very nice. We have a question here from David. Friends, don’t forget to ding me a message if if i’m in case i’m missing your hand up. Thank you, David.
Thank you. So I recall that Albert Einstein was asked the question, you know, if he were to come back in 500 years, what question would he want answered? And I believe he said “I want to know, is the universe a friendly place?” I’m not sure I quite understand the question, but the way I take it is “Is the universe tending towards supporting life, or is it hostile to life?”. That’s how I take it. And you know, if that’s true, are there any trends that you can see in this study of astrobiology, where you can, if not state a conclusion to the question, at least say “Okay, we seem to be finding that there is a direction,” right?
Ariel Anbar: So let me answer that, and I’ll take it one step further to what a friendly universe might be all about, right, which gets, again, metaphysical and spiritual. So one is – I think I mentioned before, I have colleagues at ASU who make a pretty convincing case – I think the current science, the best understanding of the science of life and planetary habitability, would agree with this – that the universe probably is a pretty friendly place for life, right, that it’s probable that life emerges pretty easily when the conditions are right. I think most scientists who study this will agree with that as a bias, right. It’s not a proven fact, it’s just a hunch, right. It’s an intuition. And that’s why we get excited about looking for evidence of life on Europa or Enceladus, right. You know, we wouldn’t get excited about it if most of us didn’t think that it was likely that there could be life there, right, if we thought these were inhospitable environments. So there is this tendency right now, based on what we know, that to think that the emergence of life may be kind of an inevitable planetary process, just like other planetary processes, like the emergence of continents, the emergence of atmosphere. You know, that once a planet is going for a while in certain ways, you will eventually get the organic chemistry going to get life as we know it. So it may well be – and I think if I had to put money on it – I wouldn’t put a lot of money on it, but I would put money on the side of the table that says that it’s probably a friendly universe for life.
But I think there’s another layer of friendliness, which is – okay, so let’s say it’s a friendly universe for life, and let’s say it’s also not a particularly hostile universe for the emergence of intelligent life like us. Let’s say that there are many other civilizations out there. So here’s the “friendly” question: “Are the rules of the universe such that on any planet that has life, you’re going to get evolution and intelligence that will develop social behaviors, that will promote cooperation and ethics, in some ways as we might know them, in their alien context, but still, right, versus aggression and violence and destruction?”, right. So another layer of what a “friendly” universe might be might be one where the rules, not just of physics and chemistry, but of biology and social behavior that follow from them, are such that cooperation, and ethics, and selflessness, and tikkun olam, and these sorts of ideas, right, are universals of intelligent species. That’s, you know, a nice idea, maybe it’s all wrong, right. It may be quite the opposite. And in science fiction you can see we’ve speculated on both things in the popular culture, right, on both sides of that.
Shmuly Yanklowitz: So if I can jump in with a question of ethics – and I honestly don’t mean this to be a question that’s offensive, I’m more interested in just the types of answers you could provide here. Why should we invest money in this study? Meaning, as Jews, we know we have ethical obligations to our families, our Jewish community, to those who are suffering in poverty, to the study of the human body and health, and the list goes on and on, right. But the allocation of billions of dollars to this study, what would be moral justifications as to why there should be serious investments in these fields?
Ariel Anbar: I mean, there’s the sort of more spiritual side to that, and then there’s the practical side, right. The practical side is that, as folks who are biologists who are involved in this article can articulate better than I can, you know, right now biology is the study of n of one, there’s only one example of biology, right. And so the basic rules of biology, the laws of biology – I mean, it’s a little funny to talk about laws of biology, right, because we only have one example of biological systems, right. They’re all based on DNA and RNA, proteins, being the same way, right. We don’t actually have enough variety to actually understand what those basic laws are. If we found just one other form of life out there, even just bacteria, that was of independent origin, almost certainly the details of how it works will be different. But the underlying principles will be similar. We’ll have something that we learned from, that we start then to turn biology into a real – a deeply, fundamentally, foundationally comparative and experimental science, like physics and and chemistry are. I don’t know what the practical benefits of that would be, but they almost certainly will be profound, right. It’s hard for me to imagine that understanding better what is life, and how it works, wouldn’t have all sorts of very practical ramifications for us. So if I were a better science fiction writer, I could probably come up with some.
So at that level, we could certainly give you sort of practical ethical justifications, which is probably what you really want or need, depending on where that question is coming from. But the bigger one is that this is actually, in the scheme of things, very little money that goes into this, compared to what we spend on many other things. And it is money that is going towards us trying to understand our place in the universe, which, you know, I think everybody here is probably spiritual to some extent, or we probably wouldn’t be part of this community – it’s obviously something we value, right. So I think, again, you look at the popular culture and you see that there’s a lot of interest in this. It’s not ubiquitous, right, not every human, but a huge number of human beings are very interested in understanding what is our place in universe. And I think, then, there is a follow-up practical angle to this that becomes the responsibility of religious communities others to deal with, which is: How do you translate our understanding of the universe, right, and our place in it, into behaviors and actions that are profoundly important for human beings?
So I think I would argue that probably the single thing science has done more than anything else – I mean, well that’s too strong – one of the most important impacts of the space program, of sending men to the moon, was turning back and looking at Earth from the moon. And that picture of, you know, Earth as this pale blue marble sitting in space, you know, which became this iconic image, right, from the original Apollo 8, of Earth sitting in space, and in emptiness, that image, and the thought that followed from it about the specialness of Earth and the fragility of Earth in its cosmic context – you know, I think that has had a profound practical consequence for how we think about the environment, and for our caring about the environment. And so I think there’s a whole dimension there that, by understanding our place in the universe, it’s not just a philosophical thing, it comes back to us thinking about how we should behave with respect to the planet, and in certain ways, with respect to each other.
So I think even the spiritual has a profound practical consequence, which as a rabbi I assume you agree with, right.
Shmuly Yanklowitz: Rabbi Mitelman was going to jump in here.
Geoff Mitelman: That’s an important piece. There are a couple of people who have done a lot of work – Adam Frank, who is at Cornell, has done some incredible work on understanding our place in the universe as questions about environmental justice. But I think the other piece is that science doesn’t tell us what we know, science helps us understand what we don’t know and what there are still questions of. Someone said it’s the difference of searching versus browsing in a bookstore, right. Like a search is a targeted search of “I know what I’m looking for and I found it,” but browsing allows us to create serendipitous connections, and you didn’t even know these were things that you needed to be able to look at. So if you are starting by saying “I am looking for this particular answer and how to be able to solve it,” that’s one direction, but I think we also need to be investing money in “Here are the kinds of questions that we don’t even know that we need to be able to ask, questions about.” And that’s sort of general scientific knowledge there, the compendium that we have of knowledge that increases knowledge, which then increases new questions, which then creates new knowledge, which creates new questions. And that then redounds on questions of education, of being able to educate our children, to be able to have more knowledge now than we did previously. And so a lot of science is going in with I think this is what the question is, but I don’t know. And I think we can’t invest in that answer of saying “Here’s the answer and I want to see if this is accurate,” it’s “I want to find out what is this going to do.”
Shmuly Yanklowitz: Very interesting. So AJ has a question on the side here directed to you, and to me. I’ll let you take the first stab.
“If life is found elsewhere in the universe, how would that impact our relationship with divinity? Would anything change? Would everything change?”
Ariel Anbar: So the last one is easy, I don’t think that everything would change. I think some things might change. I think it depends on your notion of divinity. I think different religions might have different challenges. I don’t want to speak for the religion, but I think in Judaism, I don’t see that major a challenge, right. I mean, I’d be curious to hear from from the rabbis here – if you see a big challenge to their – if we find that there’s alien intelligence, whether they’re Jewish or not, right. So there’s more tribes out there that, you know, that do or don’t know of God, right. I mean, that’s not fundamentally theologically challenging. I think if you’re Christian, it poses interesting challenges.
Shmuly Yanklowitz: So I have two thoughts here. The first is that I think that Judaism, by and large, certainly with many exceptions, embraces anthropocentric theology, that humans are the pinnacle of creation and the center of existence. And I think that would really challenge that basis of the highest obligation, as to saving human life. The second is that wherever there is suffering, there is moral obligation. If we were to find that there is sentience among other beings, that would raise profound questions of moral obligations–
Ariel Anbar: To those other beings.
Shmuly Yanklowitz: To those other beings. To look at one other direction, what about rights? What if they actually had more to offer than we did? Do we have rights to claim? Okay, Rabbi Mitelman, you’re gonna jump in there, yeah.
Geoff Mitelman: Yeah, I actually wrote a piece for Nautilus, which is a science magazine: “Whether there’s a multiverse or not, Judaism can take it,” of the other question, not just life on the universe, but what if there are other universes too? And that’s something that also we don’t know the answer to. And there are a variety of different ways of thinking about this, that I think Judaism and its view on theology can adapt and change. And I don’t think it would totally eliminate Judaism, but theology would change, in the same way that the language that we talk about God has changed over centuries, and has incorporated in new scientific knowledge.
So you know, when we take the Torah out, it says “Adon ha-olamim,” not “Adon ha-olam,” “Adon ha-olamim,” which is “The ruler of all of the universes.” Now, I don’t think that means that there is absolutely a multiverse, that the rabbis knew that and that they literally and they’re literally were going to talk about that in their liturgy, that there’s a “God of all the universes” here, but we would be able to say if we were to discover, you know, life on other planets or life on other universes as well, we would be able to adapt and change. We would need to uh but your language, Professor Anbar said at the beginning, of this idea of chosenness – it doesn’t negate, you know, Judaism being the Chosen People, that doesn’t negate God having a relationship with other people, right. There is a specific kind of relationship that happens under certain parameters, but it doesn’t mean we’re better, it means that there’s a specific element here, and the way that God would interact with other other beings would be a different kind of relationship, just as God has a different relationship with different people throughout the world.
Shmuly Yanklowitz: Great. So we have time for one last question from Lois here on the side. She says: “I wonder if there had been life on other planets in the past, rather than something there presently. We know the Zohar says that God created and destroyed many worlds before this one, but obviously we can’t know this about something destroyed. But do we know anything about history in this regard?”
Ariel Anbar: In terms of other worlds, no, but that gets to this question of “What’s the lifespan of intelligent civilizations?”, right. I mean, maybe they tend to live very short lives, and we’ll go out there and we’ll find evidence of ruins of “worlds destroyed,” as you put it, right.
Shmuly Yanklowitz: I missed one other question – Dudley Cunningham has a question he’s been trying to get in, excuse me for that.
Thank you. A few minutes ago, we were talking about how if there was liquid water on a planet, if it was the right distance from its sun, life would very probably evolve. Would you say that life would probably evolve – intelligent life would evolve – on its own, without some sort of, you know, direction, directionality? I mean, I’m thinking of the shape of our ear, and the connections in our brains, seem to be so involved with – you know, there seems to be intentionality about that. And I was wondering if you wanted to comment on that.
Ariel Anbar: Intentionality is a difficult thing, because it’s always retrospect, right. So it always looks like it had to be that way, and was purposeful to get this way, because that’s what you know when you’re looking back, right. My biology friends would tell us that there’s no intentionality, and there’s no directionality, in that even most of my evolutionary biology friends would say that even the emergence of intelligence is the result of a series of accidents and may or may not prove to be actually a successful biological experiment, right. So that would be that would be the scientific view, which is a little disappointing, I know.
Shmuly Yanklowitz: Beautiful. So we need to pause here, and we’re very grateful to Professor Anbar for this wonderful opportunity to learn with him, and that he’s here in our community and that we get to see and continue to learn from him. And thank you Rabbi Mitelman for helping us launch this program forward, and all of you who are going to join us, please give us feedback, please give us continued ideas, please follow our upcoming uh programs. We’re offering – mark on your calendar January 21st, Evgenya Shkolnik is our next science and Judaism program. Have a wonderful day and see you all soon. Thank you all.