>> booktv is on twitter and facebook. we want to hear from you. treat us twitter.com/booktv or post a comment on our facebook page facebook.com/booktv. >> good evening. i am barbara stover chief of community programs here at the museum. it is my pleasure to welcome you to an evening with david grinspoon. here at the national museum of natural history through research, exhibitions, programs and online resources we help promote the natural world and our place in it. we aim to inspire dialogue around the important scientific

issues of our time. tonight's program is one of our after hours offerings. we include film screenings, lectures, conversations like tonight. and game nights. and our evening with a series of features leading researchers and thinkers and conversation with the museum director and paleontologist kirk johnson many of you have joined us in his engaging conversations between kirk and speakers or guests like evolutionary biologist wasn't, journalist eddie young, science exchange director and merchant, philanthropist david rubenstein and most recently, president of the university of maryland baltimore college, freeman -. this spring will feature florence williams as she explores the science of awe --

i would like to thank -- before we get started i would like to take a moment and encourage you to complete and turn in surveys. we learn a lot from your input. and we use the information to develop our programming. thank you in advance. also, please remember to turn off cell phones. now i would like to introduce our featured guest, doctor david grinspoon. david is an honest-to-goodness esther biologist. a prize-winning author. his latest book "earth in human hands" explores a transformative role that humans have played in this. now known as the "anthropocene" and provides solutions for better stewardship of the earth.

david will start out with a short talk. after which he will be joined on stage by kirk johnson for a conversation. then we will open the fourth two questions from you, the audience. then we will conclude with an opportunity to purchase david's book and have him sign it in the gallery outside the auditorium. i think you're in for a treat. and now, i would like to welcome david to the stage. please join me. [applause] >> thank you so much. first of all for coming out tonight. it is great to be here at the magnificent smithsonian and i am looking forward to talking with kirk johnson. someone i have known for a couple of decades and his work, have long admired. what i want to do now for the next half hour is that you about what is in my new book

"earth in human hands", why i wrote it and lead you through some of the ideas and then i will stop and talk and hopefully hear what you have to say. why would and astrobiologist write a book about this? we are the ones who study the possibility of life elsewhere. i do feel like this perspective, my day job as a planetary scientist, someone who models the evolution of other planets in comparison to earth and thinks about habitability of other environments.and how planets gain and lose habitable conditions. you feel that it gives me a slightly different perspective on earth and even on the human presence on earth that i

decided was worth trying to put down in some pages. i want to read you a little bit from the very beginning of the book where i tried to address this question of why astrobiology is relevant. first, is this working? i also want to start off with this quotation from doctor martin luther king. that i just love where doctor king says if we are to have peace on earth, which i also take to meet if we are to build a sustainable civilization, our loyalties must become, must transcend our differences and we must develop a world perspective. i feel that one of the messages i tried to get across in this book is that if we really look at ourselves, honestly through the lens that science can give

us. and see where and who and what we are on this planet, would be multigenerational and global perspective that planetary science naturally leads us to. then that knowledge does lead us towards developing a world perspective. so that is one of the things which if you do read the book, i hope you will take away. why would and astrobiologist write about humans on earth? i'm going to read you a little bit from the very intro of "earth in human hands". gauging over the fluctuations and transformations in earth's multi billion year history, i'm struck by the unique strangeness of the present moment. we suddenly find ourselves sort of running a planet. and while we never anticipated or sought. without knowing how it should be done. we are at the controls but we are not in control.

this book is my view of how we got into this situation. and where that leaves us now. we are witnessing and manifesting something unprecedented and completely unpredictable. the advent of self aware geological change. as an astrobiologist i study the possible evolutionary relationships between life and the planets that may host it. i see the -- as an intricate step between earth and that biosphere that has been going on for 4 billion years. a lot of those subject to the same as being too self aggrandizing for destructing human centered viewpoint.but this is well names because it represents a recognizable turning point in geological history brought about by one species.

anthro. i believe that more than the extreme end of the ignitable physical changes to the planet being caused by human influence, it is this going self recognition that is really fundamentally different and ultimately promising about the "anthropocene". many species have changed the planet to the benefit or detriment of others. but, there has never before been a geological force aware of its own influence. and i have another little snippet here about the planetary perspective. the planetary perspective allows us to step away from the noise of the immediate presence. to see ourselves from a distance. in time lapse. when we do, what we see is not just a problem facing our civilization but an entirely new evolutionary stage in the development of life.

seeing ourselves as a geological process we see upon entering a phase where cognitive properties are becoming a major agent of global change. hurts biosphere gave birth to these thought processes. which are now in turn feeding back and reshaping is changing planetary cycles. a planet with brains? fancy that! not only brains but wins in which to manipulate and build tools. we are just beginning to come to grips with this stranger development. like an infant staring at his hands. we are becoming aware of our powers but have not yet gained control over them. the planetary perspective provides us with a kind of out of body experience. hovering in orbit and watching ourselves sleepwalk through it so disaster of our own making. now, can this experience help

us to shake ourselves awake? for all of the history earth has evolved without us. we have always seen ourselves as autonomous actives on a path of monetary backdrop. but now we're beginning to see that our futures, those of humanity and of planet earth are tightly conjoined. if human civilization is to persist and thrive, we will need a completely new and different view of our planet and of ourselves. in which we acknowledge both our deep dependence and are increasing influence. wayne visions of a future in which we have applied our infinite creativity to the task of living on a finite world. we have embraced our role and become comfortable and proficient as planet shapers. and learn to use our technological skills to enhance the survival prospect, not just of humanity but of all life on earth. my name for this vision is wise earth.

a recent scientific growth through enriches the story. the xo client revolution. as we long suspected and not confirmed this universe is full of planets orbiting nearly every store. it is inconceivable that we could be the only technological transfer it entices to underwear the parallel dramas may have unfolded in distant worlds. two other planets also grow inventive brains and of causing themselves problems? two other species develop technology and build civilizations that create dangerous instabilities on their planets? how do they cope? to planetary biosphere is become self-aware? the anthropocene leads us for the search for extraterrestrial

intelligence. how we fit into the planet and what kind of future we dare imagine. 100 million years from now, what will our time has been? a brief climate spasm that earth shrugged off and largely forgot? leaving it in fees of bizarre plastic objects? or the beginning of a lasting new phase where the biosphere finally woke up and adjusted its grip on the planet. so, that is often the intro. excuse me, and hopefully it will give you the perspective that i am advancing or attempting to advance and in the first part of the book is called listening to the planets. i trace some of the history of this relatively recent ability that earth has to send little bits of itself back out into the universe from whence it all

once came and explore. after 4 and a half billion years of earth evolution, one species evolved the strange ability to start launching little bits of earth stuff circling the planet, observing ourselves and also visiting the neighbors and sending signals back. and what have we learned from all of that? a lot that can fill many books but what i focus on here is what we learned about earth. from our explorations elsewhere that may be useful in our task to manage ourselves and our relationship with the planet. there are many insights that we gained into earth. profound fundamental insights about how our planet works. that have only come from leaving and examining other

planets. getting other examples. getting some perspective on what is going on here. it is like t.s. eliot said in that famous poem that i will now slightly mango about the end of all of our exploring when we turn to this place we started and see it as if for the first time. i think he said it slightly better not but you get the idea. hey! i am an astrobiologist not a poet. then many of these insights and i have a section of the book reconcile this but they involve ideas about earth's geology and the way that the surface relates to the current moving in the interior and how that is bound up with climate evolution through these great cycles of carbon and nitrogen and oxygen that unite the atmosphere, the surface and the interior of the planet. and the role of the other planets and the rest of the solar system and affecting

earth revolution by impacts. the fact that earth has been hit repeatedly like the famous asteroid years ago with the dinosaurs. and the way in which our climate has been affected by the gravitational torquing from other planets. many of the connections between earth and the other solar system came out of this enlarged view from interplanetary exploration. but one of the most profound insights has to do with the role of life on earth. by comparing earth to our apparently lifeless neighbors, venus and mars we gained an appreciation of the deep and profound extent to which earth has been transformed by life. early on in the history, each of these three planets went through a kind of catastrophe. a catastrophic change.

venus became an oven, mars became a freezer and earth came to life. it was completely transformed, not just in the obvious ways where our atmosphere for the composition of the atmosphere is strange compared to other planets because of the influence of life and all of the oxygen and methane and other things. but the surface of the planet, composition of the ocean. and even the interior of the earth we now believe over the long run is affected and maybe even controlled by life. seven a really deep way, it is hard to separate the living and nonliving parts of earth and earth is in a sense a living world. kurt went down a path, a junction of the other neighboring planets did not take. we are still trying to figure out why we have some ideas. but earth went to a branching point early on in history. there's a chapter in the book

or discuss this. it is called can a planet be alive? about the profound role of life in determining the nature of our planet and in a way that is a bit of a set up for the next part of the book where i talk about human influence because i contend that we are at a sense in another branching point in planetary history. we could be. it may be equally as profound as the origin of life was in transforming our planet. the origin of cognitive life or life that is influencing the planet through cognitive systems. the next part of the book is where i sort of summarize human influence from the earth's point of view. if you will. in this section is called monkey with the world. i want to review a little bit from the very beginning. of this section, monkey with

the world. it is called something new. it starts off of course with the grateful dead quote. who can stop what must arrive now? something new is waiting to be born. have you noticed that something strange is happening to earth? take a good long look at this world. a dazzling blue with spiraling clouds, spinning their store darkness. dayside glinting and slowly bringing son. winter white pulsing between north and south as earth ambles through its orbit. now, imagine you are a very patient alien regarding earth over the eons. if you have been watching carefully for say - the last several billion years, you have seen a lot happen. the continents drifting around the oceanic globe.

coalescing and breaking apart. animated pieces in a morphing spherical movement.the polar caps -- throughout all of the changes, the nightside remains a nearly unbroken black. and the dayside continents are the stark dull gray of bare rock. after 4 billion lonely years a green french first edges over the land and the night starts to sparkle with occasional forest fires. still, for the longest time, the unlit hemisphere remains as black as the starry space surrounding it. the dark interrupted only by these fleeting fires and by occasional flash of lightning or splash of aurora. until - very recently, in the last few hundred years just a twitch in the life of the planet.what is this?

something new! suddenly, the planet lights up in a peculiar spidering pattern that seems to reflect an organic process but, but something else as well. something cognitive? starting in a few isolated river valleys and coastal areas, glowing points appear. then stitching together and spreading along widening and brightening webs. hugging the shore as it eventually glowing in patterns and the interiors of the land. the dayside image of dark lines becomes visible. bonding between these nightlights. egypt swiftly surrounded by a growing grade of geometry. two regular movement a small wave generated objects start crossing the ocean.at the same time a host of other accelerating changes are observable in the atmosphere, the land, the ocean and the

ice. finally, just 60 years ago, a blanketing misfit interval in this fast forward view. began at the curious anti-capuchin with small bits of -- little insectlike constructions of refined metal. they start leaping back off the planet. first to the nearest world and then those farther afield. sending pictures and other information home to their inquisitive builders. signaling the arrival on earth of curiosity and gravity defying technology. yes, after billions of years of geology as usual, something new and strange is definitely happening here. what is the meaning of these new changes? and then i tell you, i make an

attempt to characterize what is happening on earth now from a planets a logical point of view. one thing we learned when we do that, if you study the long history of the earth is that earth has been through a lot of catastrophic changes. it is not the first catastrophe to be here and it is even true that we are not the first life form, the first species to radically transform the planet. for instance, these little guys, to bacteria about 2 and a half billion years ago completely transformed the planet. they may not look like planet records but they are. these guys discovered a new energy source. and exploiting that source where they polluted this planet

and -- they look innocent enough, don't they? but with this discovered was solar energy. they learn how to use solar energy to break apart carbon dioxide and make organic stuff. in the process they polluted the planet with a dangerous gas 02. those who love oxygen, i mean i know i do! good stuff, good stuff. but that is because we have evolved to tell ourselves of these exothermic energy releasing reactions that happen when organic molecules made oxygen oxygen first appeared, organic life was defenses until

we evolve respiration if you have a power plant in every cellular body that uses those reactions. that's how we live. when it when it first appeared not only was it poisonous but it crashed the climate. we think there was a methane -- it probably led to the greatest palio proterozoic when the earth became frozen over. these guys did a lot of damage. but we don't say those irresponsible bacteria. how could they? what were they thinking? because materia do not think. they're just bacteria! but at the same time we see ourselves behaving in a way that is perhaps analogous. and of course, those of us that are paying attention feel a great sense of responsibility about this. and so what is the difference? in an effort to probe the question a bit i looked at different kinds of catastrophes

that can be planets. and i think that perhaps they fit into four categories. four kinds of planetary change, categorized with respect to the influence of life. what i call planetary changes in the first kind, these are random things that happened when bad things happen to good planets. an asteroid clausen, a big birth of mass extinction. these were catastrophes -- >>

>> this is in a sense what we are finding ourselves doing to the planet now we are causing in denver in catastrophe because this is what happens when you have influence that extends beyond your awareness i see this with traffic because if you look at this here you have a species to have a great job to solve a local survival probably not aware of those global effects they did try to drive home from work and each car is driven with a person of agency to see around obstacles but then talk about the global transportation system? nobody. so we are participating but

don't have a sense of agency this is like a child who has not developed situational awareness so they could do others harmed is by simply not being aware of the extent of their influence and smashing into things. inadvertently catastrophe is one we have heard a lot about the fact we are jacking up of carbon dioxide in the hemisphere with tella combustion and other means to burn fossil fuels this is a great animation showing it comes from and where it is going and you hear about the curve the decades rising 30% over my lifetime and all the

things happening as a result the alarming decrease i will not dwell on that now because you know, about this. another example of inadvertent change is the ozone hole discovered in the '70s that was discovered in part because we were exploring the of planet venus we noticed we your interaction with oxygen compounds in the smart scientist said wonder if that could be happening. so here we thought it was nice and safe and a non-toxic but then when it diffuses into the stratosphere does something else starting to destroy radio's all their fortune in the rediscovered it in time. there was a global

conversation of course there was the argument that led to agreements and treaties and this is a problem that is actually been fixed so it is my first example of planetary changes of the fourth kind, intentional. it shows a proof of concept we have the ability to respond in a different way to knowledge of the global effect we're having. not that it will be this easy and every case but at least it shows or demonstrate something important that there is another way the problem can be the way we responded to humanity. also other intentional change the main problem is the need to transform our energy system in such a way

that they do not destroy those natural systems that they depend upon it is under way the media back to that in the discussion we are clearly moving in that direction that is inevitable just how fast can we do that and how much damage to redo along the way? but if you look cataloger timescale i feel like one of the points of the book we are obligated to because now we find ourselves with the geological force we have to consider ourselves honor range of time scales think about the type of world relieving for descendants descendants descendants to have a long-term plan and vision so once we get over this than what? then what

are our responsibilities? that is a longer-term threat to we can see coming if we can have that ability to avert them that we have that responsibility to do so talk about asteroid impact the one that got the dinosaurs will not be the last one even an i.c.e. age in the long run we know that the solar system is full of lots of stuff this is data showing earth crossing castrates each is a real unknown object that can impact the eric. did not lose sleep over this. [laughter] i continue other things that our more important although you probably don't need my help, but in the long run this will get us but it doesn't have to i'd like the dinosaurs we have a space program to deal with this program -- problem.

also the fact over the long run climate is not benign. we have an allusion the reading will be fine if we leave the earth alone and left to its own it will be a paradise for ever because we came along in an unusual time of history of relatively warm and stable climate of the last 10,000 years but that will not last . we know what to go to another i.c.e. age we will not survive and other species will not survive. it is nothing to worry about except i think we do have to worry about what do we envision for ourselves on the planet? it is not enough to avoid short-term but jimmy picture ourselves

having a more constructive role on the planet? going in to the further future of consideration in their want to wrap up here to get into conversation but i talk about the search for extraterrestrial intelligence it as a way of thinking about our for future liggett of literature is about the longevity of civilization in the crucial unknown factor of many species are out there is how long those civilizations can last people of been thinking about this since the late '60s but there is an interesting convergence that we realize the central problem that confronts us is

the same as is it possible for technological civilization to have long-term sustainable relationship? when we think of that ideological timescale we usually think about the past but it is interesting to think of the future as well. but people tend to talk as the new epoxy -- epoch when it is often accompanied by a mass extinction. there have only been for eons that is a major transition of planetary shift back when everything

was hellacious nothing lived and one marked by your gin of life which is this boundary than when life took over the planet when the oxygen and catastrophe happened then finally where we live now with life became complex we're still in this time but with this transition of cognitive life potentially the eons boundary? not just a function ration but a transition in the way life relates to the planet. so to be that eons would have to last a long time we will not know for millions of years if it turns out

that way. but to think about what is happening now as cognitive creatures are in a fundamental different relationship with the planet in this means the time of wisdom that is only if it is sustainable so therefore those are some thoughts. i want to read you one last passage from the end of the book the last chapter by talk about the human relationship with planet long term which i draw upon from the work of one of the scientist here at the museum who has done some very interesting work and you learn about this in the halls of human origin. but human history has been

determined by quiet for a when negative climate for a long time as climate change survival machines we have reinvented ourselves in the face of existential threat and a large our ability to cooperate and invent our way out of the situation. we need to do that one more time to a larger were circle to become more global to find the new way to be in relation to the world some talk about pessimism and optimism in the power of negative thinking toxic fatalism and the doomsday scenario that is so widespread in our assumptions that they can be a dangerous self-fulfilling prophecy so i talk about constructive pessimism that

the very end of the book to turn that around i've got this to be inappropriate because you're at the earth and optimism summit so this is all areas of the book not the last two paragraphs because a want to leave the cliffhanger. >> right now the subject of the future is ripe with anxiety visions of a pox a lot -- apocalypse the topic of anthropocene is with the doom and gloom this is understandable but not the whole story do not dwell on the prophecies to the point where they do become self-fulfilling opposed on the contrary the true anthropocene should be welcomed although only in its infancy don't fear learn

to shape it. the awareness of versos and geological change was propagated will give the capacity to take your future into our own hands understandably we are uncomfortable with the planetary engineers sometimes it is manifest as denial but this is our task we cannot afford to wallow we have to stand up and looked in the mirror and wake up to find out we are the eyes of the world. early in this chapter i talked about pessimism there also optimism cosmic optimism stemming from the belief in the universe will bend towards life and

intelligence and what happens doesn't really matter anyway there is plenty more where we come from. data driven and historically based optimism which focuses on positive indicators poverty, malnutrition and unfair mortality levels of educational the rise communication continues to be cheaper and easier population headed toward stability wind energy is getting cheaper and will continue to do so to build environmental sustainability of the pragmatic optimism we don't know what will happen so why not spread hope and encourage engagement? technological innovation is an accelerating ways ways that we seemed magical or not imminent and

exhilarating but above all unpredictable weather uncertainty there is also hope andrew for faith in ourselves a believe we're just getting started on this planet. nobody knows the odds to navigate the evolutionary obstacles but there is a real hope and it is this that are evolving technological capacities can allow us to maximize our progress equipping yes with those novel threats we have created to become something new in the process. we have done this before. [applause] >> nicely done.

this is a great booker really recommend it to i really enjoyed it i did not reach the final paragraph before i got here but it is full of these cool little phrases and it is very clear that he had ample time to write this book and i know this because in my previous job as the first curator of biology was so bold higher because the collection was very small which was the study of life outside of birth yet to be discovered. [laughter] and he was a tough curator because he had no collection

but near the end of my time i got a job as the astra biologist of the library of congress and then moved to washington d.c. and thought that was pretty cool. tim was later followed you to this job so to watch this evolution as our time has moved forward. and telling you about the book it is the global bank's that we struggle with with spatial and temporal context one way to take a problem is to stand back it spreads out the time scale one of the things that i love is that as a people we have a tendency to put ourselves and to the apocalypse time as of next tuesday and that it was stretching time out

but just on a journey. and then he parked within the neighborhood of the solar system in the different neighboring planets that the astrophysicist with book that the climate history of venus or mars and that defuses the discussion of climate change if you talk about other planets. so what really struck me in the book that the majority of kids born today will never see the milky way?. >> that is a sad statement dealing with the urbanization such talk about how the way we live is how

you think about our planet. >> yes. that struck me when i heard that statement and i haven't actually checked the map but it does make sense because we are increasingly urbanized with that trend so it is a problem although not people are trying to deal with a light pollution and fantasize part of this long-term vision of what that might mean to be a healthy civilization might involve leaving parts of the earth on urbanized and maybe that will not always be true but it is strange to think the stars that have been such a huge part of human experience that the kids will grow up never to see the milky way so that is emblematic of the fact that

we are really living on a different planet than any generation of human beings and it is an open question if we are well equipped but i have learned how incredibly reinvented of the human species is and that gives me hope that when i say we have done this before there are amazing moments in human history we almost got wiped out maybe down to a thousand people or less that we survived that coming up with a completely new way to be social and get food maybe we need to do that again. >> been trying to convince people nature is wonderful while sitting inside a building that is the natural

museum dilemma does that experience in foreign your thinking?. >> it did. i love that interdisciplinary nature and the challenge to be the astro virologist you are right where is your collection? there are some fun answers to that one is classified mitt other is my cabinet of aliens but there is a certain sense that all collections that it is the interdisciplinary field it has been called a science with no subject but you can also say it is also the

history of life on earth. so then all the geology collections and paleontology collections become relevant to this story which try to piece together with cosmic evolution because i just learned so much from the curators and the opportunity to interact with so many is a wonderful experience i recommend it. >> talk about the twisted gift of global warming. >> yes. one of the themes in the book is our task is to recognize we are planning changers where we reach that point where we don't have the option not to be there are possible futures we

could devise to go back to non intrusive areas of society but if you say okay to reduce human population to a few million that is not realistic. there will be billions of people for some time to come so we will be planet changers we have to manage the planet. so global warming is the first lesson of that the first thing that is happening to make us aware of what is going on but it will not be the last that is the gift of global warming that it wakes us up to the reality of ourselves as a planetary force. and like a lot of things happening historically right now i would not wish upon us

it is a silver lining of awakening and arguably in the long run solving this problem and i think we will that would be the time when we woke up to the planetary nature. >> we're basically the same age their 3 billion people on the planet now is 7 billion in the next 33 years another 2.5 billion will join us so we in a critical moment i want to know what kind of an optimist you are?. >> i guess i would say all of the above i do think i have some of that cosmic optimism where i find comfort in the knowledge i

think what is happening here is not completely unique and they don't want to get all mystical but the universe does have a tendency to create intelligence and there are wise civilizations' out there it would be nice if we could join that party and that is my other pragmatic optimism and i do believe because there is a huge range of uncertainty that those who called to our over confident in their knowledge it is not valuable to promote a positive vision so i mention all the positive indicators are reasons to think we could get over these comps that we are confronting right now as a long-term trend as good i think 100

years from now it will be like waling we did that too long but now we stopped and now there are still some wailes and the manchin population of projections show that it will stabilize so we will get to another world with a stable population i think that is inevitable but how much damage do we do along the way? but my optimism partly comes from my long-term time frame because there will be a 22nd in the 23rd century. >> will the kids born today see the 21st or be 22nd century citizens? and then

you are on to the races. >> and the cosmic scheme stand back and look at it is an overwhelming and difficult to solve problem or not? but i am curious as a side question what about the signature of extra terrestrial life in the next five years?. >> five years is pretty short time scale to predict i will wiggle out a little bit but this is a time for the search because our knowledge is expanding rapidly in certain ways of this just a matter searching a little more and better

than it will become known to assume. but because of the xl plan a revolution we have discovered the sky full of planets and we did not know that when we were kids we still though almost nothing what they are like but we can start to say an oxygen atmosphere and methane and look for bios signatures that is right around a corner may be closer to 20 years and then the solar system which we have not checked closely enough there could be life there five years we have to get pretty lucky but within our lifetime? then we have a decent shot. >> so that was just a few

years ago with the planets?. >> the first was in the late nineties but they were reared really it was the mission about a decade ago we started to say a planet planet planet. >> so this whole idea we cannot engineer our way out of this?. >> go engineering is a term it is a daunting concept that we think we know enough to fix the planet by engineering a solution but i have a different take on it. so what he just mentioned radiation management to fix

climate change putting stuff up into the atmosphere like carbon dioxide particles and were that climate is cool down with stuff bin the stratosphere than the idea of carbon captured through the iron into the ocean to cause a massive algae bloom they were kong paper but in my view it is dangerous so the system is complex and rears still a lot of unknowns so for us to say we don't have to worry about co2 emissions or the? fix that is safe to not have to change the energy supply.

but in the long run is the obligation to transition to the intentional planetary changes. but even when we plant trees it is benign. that is contrary intervention in the planet. and with different kinds of ways to consciously intervene in the planet. at the same time we're obligated to learn more about the planet and to

handle our role on it. >> with those spare objects to devise ways. >> there is a lot of junk out there we think we know ways to change the you don't want to send a bruce willis up there. [laughter] but it would not make as exciting a movie scene but give the hour rocket with a heavy object and then pushed it a little bit too miss the earth and over time we can

do that make a policy that's trades coming decades in advance. >> so what happened to life on earth with the times? but given those recent developments i'm curious of your thoughts. >> i am scared of nuclear winter. when i mention don't lose sleep over asteroids there are other things but nuclear winter is something that is not only included in the

decision makers these things are not weapons they are suicide machines if you just explode enough it does not take much just a small scale exchanges a drastic climate change around the point - - the planet. so studying the planet mars to study those dust dorms on mars to say this is where did you fill of the planet to atmospheric particles is there anything that could make that happen on earth? and say what could cause that to happen in the future? that is what led to

the publication of a nuclear winter so ironically it would cool the earth down to be a temporary fix but it is not recommended. [laughter] it is a real effect and a possible game changer would be the end of civilization? quite possibly even with the smallest detail exchange. >> it has been 72 years as those faded into memory with those unintended consequences i read about

those people in hiroshima of who are working with the survivors person to person contact where they assign themselves to the individuals everything that they know to the best that they can to carry on that memory some people are trying to keep that alive it is so important we don't forget that. >> the last survivors are passing the direct memory into museums and with this exhibit called deep time over the last seven years it is open 779 days.

but that time it will pass in a flash is a cool exhibit because it stars the formation of the earth and then it goes into the future in takes use some distance into the anthropocene to look back into the future of life on the planet that most prehistoric is of mammoth dinosaurs but in fact, to park that where that belongs. bettis 779 days mark the calendar. that to be an early party

but the role is to help people deal with time we are worried about in the sense of what's for lunch but 33 years from now on or 70 years from now but is one of the things. what about time travel?. >> it is one of the biggest challenges to lose that illusion that all we need to care about is what is happening right now when we are alive. to create a sense to be embedded in that time as we are related to our ancestors and descendants.

i don't know if i have any magical tools i think storytelling is important and the reality of what we learn about our existence connects us with this long-term history with the long-term future so just communicating that as a scientist ruleless to communicate what i know and love my colleagues and i have learned with this project to build a more sustained and help the presence but it is funny retell the story of time as this is the end but i came to one of these earlier this year and it was a great talk but he did this thing that i have done before when he

walks across the stage to say this all stages the history of the eric 1 billion, a 2 billion that the very end was now and i have done the exact same thing. i should say now it is of little and carl sagan has that cosmic calendar of the beginning was january 1st now it is december 31st so what about tomorrow so i think we have to be careful to define time not to say that the apocalypse is coming growing up we had people who knew the end of the world would happen so they were making financial decisions based on that.

>> that fatalism is not useful this time but this is the last question how do we want people to feel after they have read your book?. >> i want people to feel hopeful, engaged and entertained. that it has been a worthwhile experience reading it. provoked thinking about things and a new way, but to me it is important because i feel lamp pummeled with these messages now that can suck out hope that is not productive or maybe not even

true so hopeful and engaged and provoked. >>. >> guest: them to do anything?. >> yes. to transform human consciousness on mass. [laughter] so what about the march for science?. >> i am excited about it it is a little puzzling i was taught that science is value neutral that is my heart as a kid and so what is great about science it is completely objective that they do not marry or test any goal. just the facts. so that it could be above the fray but now we find ourselves in a world that is

so relevant to the questions of climate change to have that objective truth is under attack. so to put science in a strange territory i am intrigued to see what they do personally and want to go rob there to make it known there is an attack is strange but nice and inspire the people want to respond to that. >> we have some questions. >> thanks for your talking

and though wonderful book a thank you achieved a lot of the goals the you just mentioned also attaching specifically on my question it does seem very accessible to all people of all opinions so just some thoughts on how we can get back to that place to agree on the fact so to cut climate studies?. >> so how can we find agreement? is very difficult and challenging because we are so entrenched and then to say they don't

think what i think that doesn't get us very far. [laughter] one way is to change the context of a the conversation. but with this accurate description as those who would call themselves skeptics but we don't like that term either for the virgin island it is pretty intense work that is compared to the holocaust deniers and there is a certain truth to that because you cannot just make up your own history or fax but the problem is if you use the phrase some people

will not listen to what you say next and i don't believe anybody who doubts climate science is evil or greedy i think they are consuming other information sources and searching for ways to communicate with other people i think it is important but i had had some success talking about this earlier on other planets because some say that nasa is cool i like space exploration so there is some credibility the models' work for venous and mars to take

that out of the context of is they don't have the magic bullet and any dead better metaphor than that produced the eighth listening is important in the conscious not to be insulting or turn people off of the conversation. >> africom meant and a question with the cosmic calendar i did not take that as fatalistic but as a comparison to the great expanse of history in general as a biologist would you think about our responsibility for diversity of species? i have heard

that description and what is your thoughts on that?. >> first of all, on your comment the cosmic calendar ahead is a great comparison i did not mean to disparage that because i grew up with that. he did an amazing service as a new way to think about time so that is wonderful it is just my foot note of december 31st but i love the cosmic calendar for:--. but it is clear the short-term obligation is to stop the mass extinction we are threatening there have

spent five mass extinctions and why and of which was that dinosaur hit so to continue that the projected rate of species destruction we have to start - - stop that long-term what are the implications after? what do we do about extinction after that? if we get through this transition in the 22nd century we stabilize the population we no longer cause a mass extinction but then what is the right rate? do we say it should be zero then we have the massive change your massive intervention if we don't

save zero then hugos? so in the long run of the immediate obligations and raises interesting questions >> 20th-century dilemma. >> ion stupidly excited because i read a book and it had me go back to school for science so as he started to see these xl planets and what we didn't expect so we say that's great now the other hypophysis so we can look at these things to say

b.c. this or that chemical signature but if you look back in our past you would not have seen that signature with bacteria at the time before they built up purpose of is there a signature we have such a small sample size with the vast universe that we will not recognize that chemical signature?. >> cry question thanks for sharing that you read that and made you want to study science of love to hear that that is what makes writing this worth it. [applause] but about your question the search for baia signatures is inherently biased in many ways we don't know anything about life in the rivers we

have one example. how can you draw any conclusions from one sample? if you have one fossil? so we have to be careful with our assumption so then we said there is a planet just like curve there will have oxygen but that is the point you just made maybe a couple billion years of further evolution where earth had a complex biosphere but not oxygen so the search for by a signature is based on a crude guess. also into more broadly search for a novelist signatures and may not be

what we are predicting but if there is suspiciously large amounts of gases that don't seem to be like the produced the doesn't improve that makes us want to pay attention. >> have a comment i hope you can respond to the adn that we are all in this together nobody wins unless everybody wins with that whole concept of what we all share the atf that is far from universal today that it is possible those who don't think in

terms of humanity. so it seems to me it isn't just a question of consciousness of the idea we're all in it together but convincing and it is not a fact maybe ethical but people need to be convinced door carefully taught. >> absolutely. to identify a tricky problem it is not enough to have a solution that you and i could agree is the right solution so to come up with a plan to solve global

warming and these other problems there are the solutions that exist but that is not enough. how do we get that global bosnian -- when the world is fragmented it is hard to tell if that is a blip of the old world view to be a perennial optimist so i see kids growing up with the much more global perspective in other countries as well to be more connected as a global citizen. so that transformation will not come overnight but it doesn't have to be perfect

it just has to be enough. there is a documentary about the '60s when they surrounded the pentagon and tried to levitate it. [laughter] they made the point that anti-war movement ultimately won but we were never the majority we were just very visible how many were there really? he said enough's. so it is a matter it doesn't mean we have to be a of global altruist the people just have to connect the dots of selfishness or in light in the self-interest they don't want to destroy a the world they and their children will live in if

they have connections that is clear to them. you can see some of the powerful players in the world starting to realize they way they to think about these things i am encouraged by the chinese not because they are a global all dressed the reality has a way to bite you on the behind if you ignore it long enough. there are a coalition of corporations and business people that is bipartisan not at the highest levels of government but other levels like state and local to realize we need to deal with this.

so the alignment of the wider self-interest with the need not to destroy the world that we've been is something that will come around with these connections between the choices and the global environment to become more apparent so the task that we think about is to make it the easy way through foresight in the bike that to be as much as possible. >> so working in a museum that are run by the creation of new knowledge of discovery in the communication of that knowledge that is what we

do. . . the solutions we are looking for and so many amazing discoveries were unexpected and for each of those discoveries was only used in retrospect. i know that you as a scientist read and speak and i'm curious if it occurs to you more

effective ways to describe the value of simple curiosity and the value of simple discovery as opposed to, let's solve a problem, kind of thinking that were involved in our. >> i'm intrigued by the point you made their where were distracting from the joy of discovery by the sense of urgency. we really need to meet both. there certainly is urgency in the science and they feel obligated to be part of the solution in different ways but science also does thrive in an environment and with an attitude of curiosity for the sake, learning for the sake of learning. and everything is to apply then we won't do our best science. that's a tough one. one thing i do like to do is make the connections, to tell stories about how many curiosity driven projects resulted in very

practical knowledge and some stories that people don't know, i mentioned about the ozone layer, that take one. people were studying in the atmosphere of venus because they wanted to know what the atmosphere was like and they were puzzled. they know it's mostly co2 and it's been broken up by sunlight, ultraviolet light and there should be oxygen coming up. but there isn't any and where is it some other science that i saw these experiments, chlorine destroys oxygen and they took the spectrum and centers chlorine there and that's what's happening. then these other scientists and this was just curiosity. other scientists read the paper and wondered if this would apply to earth's upper atmosphere. if they hadn't been curious about the other problem it would've taken us longer to discover the ozone. there's a lot of examples like that where we do our best science a lot of times when were

just trying to figure stuff out and trying to solve puzzles and somehow we have to have that i think it's healthy to support scientists who are just simply driven by wanting to know and not being forced to justify what they are doing by saying, here's to immediate societal benefit and this is what i will event you give me this funding. it should be enough to say here's an interesting problem that no one has all. >> here is the last question. i wanted to ask you to expand, slightly, i love your effort to approach the denial is proud or whatever in a different way. i thought it would be helpful -- you started off talking about the comparison between mars and venus and earth and the models

was a good way to do that. i'm wondering if you would share with us and what's the 92nd version. that's all you have to talk to trump in 90 seconds. [laughter] >> that would be a hard pitch to make. i think i'd be fired. >> were only giving you 90 seconds here. >> the fact is that they're just models, their computers. what do they have to do with the real world which mark the fact is we went to venus and we measured the surface temperature, found it was 900 degrees. they did a climate model using the same physics that we predict future climate on earth. if it's all co2 and that the atmosphere it will be 900 degrees. there's a lot of examples of this. it shows by stretching our ability to model places that we

have never been before and accurately predict what will find and verifies that we know what we are doing, the physics are real and the modeling is real. by presenting it that way we can take it out of the context where people already have their differences up because they think they're being sold a political argument. >> forty-three seconds. [laughter] [applause] what will happen next is that david will sprint off the stage before you even have a chance to jump up and greet him and rushed to the table in the hallway where he will be selling and assigning books. you should all by at least four or five copies and give them to your friends and family. please keep your heads up for future events in the evening coming up soon. the fun events and we appreciate you taking the time to join us tonight. please join me in thanking david come back.

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