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SPEAKER 1: Thank you, Lynn, for setting us up for the climax of this wonderful day. And I want to introduce the next speaker by making sure all of you understand something.
Cornell did not decide to have an Institute for Pale Blue Dots, now Carl Sagan Institute, and call up our next speaker Lisa Kaltenegger because we thought she'd make a great director. That's exactly backwards.
We were very much interested in having Lisa Kaltenegger come here and energize our extrasolar planet program. And when she came to visit to decide whether she wanted to be here or not, she said, you know, there's an institute that I want to set up. And I said, an institute, really? That's interesting. What kind of an institute?
And she laid out this vision. And half of me was really excited and the other half was thinking, how do we talk to the department head and get to the dean and all of this? And we really want her here. And is this going to happen?
Well, look at this. It's happening. And it's happening as the Carl Sagan Institute with Ann Druyan here and so many wonderful colleagues. It's really been an extraordinary odyssey.
Lisa-- you will learn what Lisa's doing in terms of her research. It's all sorts of exciting things in extrasolar planet atmospheres. And she has wonderful students here.
I was going to write down all of her awards, but I ran out of room on the paper. So I'm going to Wikipedia and just do a few because I know we're running short of time.
Asteroid 7734 Kaltenegger is named after Lisa. In 2007, she was named America's Young Innovator in Arts and Science by Smithsonian Magazine. She received the Heinz Maier-Leibnitz Prize in Physics.
Several years ago in 2013, she was selected as P.I. for the Simons Origins of Life Initiative. In 2014, she received the Christian Doppler Prize of the City of Salzburg for Science and Innovations.
And I can say we are tremendously thrilled, and excited, and jazzed to have Lisa here, in case you've been sleeping all day, as the founding director of the Carl Sagan Institute at Cornell.
And so with that, I asked Lisa to come and bring it all together for us in the final talk this afternoon. Lisa.
[APPLAUSE]
LISA KALTENEGGER: Thank you so much for being here today with us to hopefully share the excitement of the start of finding or exploring our own place in the universe in this vibrant interdisciplinary environment Cornell provides us with, based on heritage that goes back to Carl Sagan.
And we really are standing on the shoulders of giants to be able to make this next leap. And you've heard, of course, from some of those today about the first discovery about thousands of new worlds and about what's next, this whole idea that you can live in a time when for the first time in history, we can answer-- or at least take the first stab-- at the question, whether we are alone or just how other worlds are like.
I think if I could pick any time in human history, I'd pick exactly this time. And we have the pale blue dot, our own planet. And now, with the knowledge of that, the solar system, the advances in biology, chemistry, and engineering that allows us to go forward and make more measurements, we're starting to take the next steps, because what we really want is to be prepared.
Ann has shown you the beautiful image that Voyager took of our own pale blue dot. Oops. That is not it. That is it.
And to this day, this is my favorite image. It shows this beautiful fragile pale blue dot, but it puts us in context.
Yes, there is a huge space between stars. And the next planet is far away. But we are reaching. We are catching the light of these other planets, and that, for the first time, allows us to figure out what's the air on another world.
And I am very interested in the question of, if I were getting out of the spaceship, would I actually be able to breathe it.
Our space in this amazing, amazing universe positions us just about half out from the center of our galaxy.
The sun is an ordinary star. As we heard, the small stars are much more numerous. But around every one of those billions of stars, we now found is another planet, another potential world, and some of them at the right distance to potentially be another earth.
We said that's about 100 light years across. And our search space is really just a fraction of that. All these thousands and thousands of worlds are just in our solar neighborhood. We have not even gone far yet in our endeavors.
But what we can do is we can actually now with the new techniques and with our telescope catch the light. We see the stars.
This is actually not an image of our galaxy because we have nothing that flew that far up and actually had a look at our galaxy. But we do know how the assortment of the stars are in our own galaxy.
And then we look out there. And we have a look at a galaxy that just looks a little bit like our own. And we said billions of stars in ours alone. And then billions of galaxies out there. So the numbers are fortunately very much in our favor.
But let me bring this back to this beautiful image that, to me, has not lost any of its compelling information or for its compelling visual beauty over the years. It's still to date the picture of our own world that was taken from the furthest spot away.
We don't have an image of our own planet that was taken further away than Voyager took this one. This is how we see our own planet.
But now, the exciting thing that happened is you see this dot of light-- and of course, you have to squint a little bit because the instruments are not perfect. And there's always some noise that we have to get out of the data to figure out what's going on.
But if I could zoom into this dot, then of course I would see this beautiful planet with continents and oceans.
And I want to bring you back to, this is not what we are going to see. But there is a way around it. Because all of the continents, oceans, air, the biology, the [INAUDIBLE] leaves basically a spectral fingerprint, a light fingerprint.
And that light fingerprint, even though the planet is one tiny pixel, one spot of light, that's what we can read. For the small planets, we need bigger telescopes. But that's what we can read, and so over light years away, we can explore other worlds.
And we are very used to having a look at our own planet in this context, but planets could be very different.
And we were saying they could be water worlds. So just imagine a little bit more water on a world. Then you wouldn't have any more continents. You could imagine, if you like to sail or to surf, you would have a wave that will never break. It's got to be a bit of a problem if you want a break between sailing, but other than that, while it's going, it's great.
But we're finding worlds out there, as Bill was talking about, that are different than what we have in our own solar system, and that to me is a big fascination. How could those work? And if they are this one dot in space, how could we tell that apart?
So this tiny dot could really be an earth, could be a Venus. And so, when you just see this white dot, you won't be able to tell.
But if you take this white dot, and you split the light and its colors-- basically what a drop of rain does when the white sunlight comes in and then you have a rainbow-- and you look at the different colors, figuring out how much energy, how much light gets and in different colors, if there are things missing, like a bite out of the apple, energy is missing.
Then you can pinpoint over light years away-- and we're doing this for the huge planets already-- what chemicals, what molecules are in the air of another world.
Because the light that's missing here-- really, the light hits the planet, and instead of this light getting back to you, what happens is the molecules use it to rotate, or to vibrate, or you used an electron to be like shifted up to a different orbit in the atom.
And so it's very specific which energy excites or gets used up by which molecule. And this is how we can read the air of plants very far away.
This, of course, is our own Earth. And you see CO2, water, and ozone here, and methane in here. And really the combination of oxygen, or ozone, and methane is what we're looking for as a signature for life.
Because it's a robust signature for life, as long as you also understand the star. That's another piece of the puzzle.
If you compare to Venus and to Mars, you see that Mars shows you CO2, Venus shows CO2, but neither of the two show you water, methane, or ozone, or oxygen, in concentrations that we can pick up with a telescope.
But you know that our own planet evolved through its geological time. We were not the same. And if anybody ever offers you a time capsuler or a time machine, please do not forget to bring your gas mask. Going back in time is great, but you might step out of the time machine and you're dead.
Because most of the time, it wasn't very good to breathe the air on our own planet for us. For life? Great. But for you and me? And that's the difference I want to make.
So if we just have a look at our own planet-- and we know from fossil record, as Lynn just mentioned, we had the origin of life pretty early on-- the oxygen photosynthesis came pretty late.
If this is the 24 hour clock, this is about five o'clock and the oldest multicellular fossils at around nine. You, me, and technology are just the last couple seconds before midnight.
So in our endeavor to find life in the universe, we are inclusive. We don't just want to look for you and me because we've got to basically narrow our search base so much if we were to do that.
But this history of life translates also into a different environment. Conditions were completely different early on when the earth was formed, and then around half of its history, this is where methane got produced by methanogens. And this is about five hundred million years ago when plants became widespread on our own planet.
And all of this is, of course, going hand-in-hand with the different forms of life that we had in our history. And so you had-- Lynn usually hits me when I say "primitive life" or "simple life" because nothing is simple apparently-- well, I do agree. Or advanced life, or evolved life, or you know, potentially intelligent life.
So all of this, if I catch the light off a planet-- we haven't done that because the telescope need to get more powerful. But what we do is we prepare for this. Because if you caught the light, this spectral fingerprint that I was talking about that tells you what the air on this planet is like changes.
This is our current planet. This is about two billion years ago. And this is when it just formed. And the spectral fingerprint of life that I was talking about is methane with oxygen or ozone. So for about half of Earth's history, you could actually pick that up from far away.
So we had this discussion at one point when somebody said, so if an alien astronomer was looking at the Earth, could they tell that there is life? Because Stephen Hawkins had just come out and said like, oh, don't send any signals. So it's like, well, if they have about 10 years more of NASA funding, they'd found us.
So whether we're sending something or not, it's probably a pretty moot point at this point in time. But this is how close, with all these planets out there, we are to such a discovery if everything aligns.
Maybe life doesn't get started. Maybe there's just one in a million chance. There's still a lot of planets that could have life out there. And we could spot it, but we would need very powerful telescopes to do that, more powerful than the next generation.
But maybe not. Maybe life is very abundant, and what we find either way is this diversity of worlds out there that we're trying to understand by doing that to put our own planet in context and understand it better.
And one of the things I wanted to just quickly touch on-- Lynn was telling you how different life can be even on the earth. It lives in very extreme environments. And my first trip to Yellowstone, I was fascinated by these beautiful colors, what basically showcased different biota.
And I was very tempted actually to swoop a couple up, and take it with me, and have a look at home, what I learned was not very legal. So then I actually decided that that was probably not a very good idea.
And I decided to collaborate with somebody who actually knew what they were doing. And so Lynn and me got into this collaboration that produced a wide spectrum of different life forms that we could isolate from different parts of the world that Gretchen Ritter was talking about as a color catalog that we're hosting here at the Institute.
And the graduate student was doing that work was with me in Heidelberg, and then went to Lynn's lab and actually grew 147 extremophiles. And I do have to say, got a little bit attached to them and didn't want to leave them behind when he left.
He is actually in the audience. It's the young gentleman over there. So he basically has done this bridging work between biology and astronomy that allows me and Lynn to think about what another world could look like.
And so if you take this together, then you say, now, if the world had a different biota that would be dominant, it would look different. But you could use this too because getting enough light to look at the individual spectre, to catch enough light to look very, very detailed is hard.
But if you think about this as colors, how does it look in the blue, how does it look in the green, how does it look in the red, and you add that signal up, the different surfaces actually would appear different.
This is why they have different colors. And that's what you could use to prioritize which of those planets look more, when you find them, like a planet that could host life.
Because even the next generation of telescopes will only give us a little bit, or will only allow us to take the light of one, two of these planets to figure out if there could be signatures of life.
So we want to be as prepared as we can by making these models and asking this question-- among the thousands of worlds or among the dozens that are close by, which ones do we want to pick? And combining what we know about life on the Earth with astronomy is one of the strong steps to do that.
And so this point that I gave you could be very similar to Earth, could be very different from Earth, could be a water world, could be a world with very, very different continents and colors.
And here, in case, this looks familiar, this is me on my computer using a graphic program, shifting the Earth and recoloring it.
So it's not at the level of this amazing logo that Christo was doing for us, but this was me saying like, ooh, how could that look like? So this is my amazing graphics skills just trying to visualize how different, even on Earth, even a planet that is the same radius and mass could be like.
And so let me come back to our place in the universe. We said thousands of planets have been found. Among those, the first ones-- and [INAUDIBLE] 29 right now-- in the Kepler data set that could be another Earth, meaning that it's not too hot, it's not too cold, and they're small enough to be a rock.
And this is just a tiny fraction of the possibilities out there because we just haven't looked far enough yet.
And I wanted to bring this back to this beautiful logo that we have for the Institute for Pale Blue Dot that Christo designed with exactly that in mind.
Because if you have a look at this, this is our own pale blue dot. And the spectral fingerprint, the light fingerprint that tells us that there is life is also the light fingerprint of a human, because we are one of the species on this planet.
But the other one that we see here on the horizon do not have any fingerprints yet. Because we are just not there yet, but we glimpse them already on the horizon. And they are measurable. These are our next steps.
And that's exactly, for me, what the Institute is about-- taking everything we know, everything we learn, putting it together, bringing the most creative minds together to ask the question, how would this be detectable in our own solar system and over light years away?
And let me bring this back to why Cornell and why now. I think you saw that right now, the time with thousands of plants on the horizon with the next big missions coming up in five to ten years, is when we need to actually start to understand what we could be finding and how we could be finding it.
And of course, here we are standing on the shoulders of giants. And I really like this imagery, because see? There are a couple planets. This is our own solar system. But with this new institute, we're linking the next ones to the search, to the spirit that Carl Sagan had and fostered here at Cornell.
And with Ann's involvement in this as well, I think what we're trying to do is get a lot of young people and a lot of interdisciplinary sciences involved in this exciting endeavor, because [INAUDIBLE] was talking about this galactic shore that we're standing on. I think it's an incredibly wondrous diversity of worlds out there. And we haven't even started to scratch the surface. And this is why it's so exciting for me to be alive right now.
Thank you very much.
[APPLAUSE]
Lisa Kaltenegger, director of the Carl Sagan Institute, shows how we can translate the detection of exoplanets and accumulate this scientific information to explore planets and life in the cosmos, May 9, 2015. The inauguration event, "(un)Discovered Worlds," featured a day of public talks given by leading scientists and renowned astronomy pioneers.
