YouSaid · the spoken record

Sara Seager

lines on the record: 135
first: 2020-08-16
most recent: 2020-08-16
sittings or episodes: 1
sources: podcast

Every line below is reproduced as it was said and linked to the record it came from. Nothing here is summarised or generated. Directory · Search · Corrections

“You can call it extrasolar. Exoplanet is simpler, but I think it's worth pausing to remember that each one of those stars out there in our night sky is a sun. And our sun has planets, Mercury, Venus, Earth, Mars, et cetera. And so for a long time, people have wondered, do those other stars or other suns have planets? And they do. And it appears that nearly every star has a planet, has a planet we call exoplanet. And there are thousands of known exoplanets already.”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“Well, at the time, it was a big deal, but it was also incredibly controversial. Because in planets, we only had one example of a planetary system, our own solar system. And in our solar system, Jupiter, our big, massive planet, is really far from our star. And this first exoplanet around a sun-like star was incredibly close to its star, its star, so close that people just couldn't believe it was a planet, actually.”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“And that's going back to that, that's what people were skeptical about. When I first started working on exoplanets a long time ago. People didn't believe we would ever, ever, ever study an exoplanet atmosphere of any kind. And now dozens of them are studied. There's a whole field of people, hundreds of people working on exoplanet atmospheres, actually. At first”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“Oxygen is a huge indicator. And that's what we're hoping that there is an intelligence civilization not too far from here around a planet orbiting a nearby star with the kind of telescopes we're trying to build. And they're looking back at our sun and they've seen our Earth and they see oxygen. And they probably won't be like 100.0% sure that there's life making it. But if they go through all the possible scenarios, they'll be left with a pretty strong hint that there's life here.”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“What's floating about? Yes, it was totally floating about. And it comes down to oxygen, which on our planet fills our atmosphere to 20% by volume. And we rely on oxygen to breathe. You hear about the people on Mount Everest running out of air. They're really running out of oxygen. Well, they're running out of oxygen because the air is getting thinner as they climb up the mountain. But without plants and bacteria, there's plants that also photosynthesizes and produces oxygen as a waste product. Without those, we would have virtually no oxygen. Atmosphere would be devoid of oxygen.”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“Oh, that's so true. And that's a big part of this growing field is how to make sure that this gas isn't produced by another effect. Do you want to... Again, pausing on that and going back a bit. It's incredible to think, but like at least almost a hundred years ago, there's a record of someone talking about. The idea of a gas being an indicator of life elsewhere.”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“So, we make this basic assumption of chemistry. That's the first thing. The second more complicated thing that I and my team work on is what happens to the gas once it is produced by life? It goes into the atmosphere. And a lot of gas is just destroyed immediately, actually, by ultraviolet radiation or by oxygen. Oxygen's incredibly destructive to a lot of gases. So the gas can be produced by life, but it could be just completely destroyed by its environment.”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“In the best days, it's like 80%. And I could actually go into a lot of detail here, but I'll just give you the simplest things. So, first of all, we make an assumption that, like us and our life here on Earth, life uses chemistry. So we use chemistry because we eat food, we breathe air, and we have metabolism that to break down food, to get energy, to store energy, and then ultimately to use it. And all life here has some kind of byproduct in doing all that, some kind of waste product that goes into the atmosphere. I like to think that life everywhere uses chemistry. Some people have imagined like, let's imagine like a windmill, like mechanical energy, just getting energy and using it without storing it. And if there was life like that, it might not need to output a gas.”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“So, interestingly enough, that entire question Relates to, I'm going to say almost my life's work, the work I'm doing now and the work I'm doing for the next 20 years. And I wish I could give you a concrete number, like 1%, like on the worst days, it's 1%, let's say, in my mind.”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“So, for example, you could imagine life like us humans, we breathe out carbon dioxide. Our planet Earth, we already have a lot of carbon dioxide on it. Well, we have hundreds of parts per million, but it has a really strong signal. So us humans breathing out carbon dioxide, it's not helpful for any intelligent beings that are looking back at Earth because there's already a lot of carbon dioxide. We're not adding to it. So if there is life on a planet and it's outputting a boring gas that's not helpful for us to uniquely identify. Being made by life versus just being there anyway, then it's not helpful. So I separated those two terms out. Soon I think we'll have evidence that planets that can support life, at least, are common.”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“We don't know what that is, and FS I called for spectroscopy, the fraction that have, we can use our telescope and instrument tools to look for light. Actually, FS was the ones that the planets that have life that actually gives off a gas, a useful gas that might accumulate in the atmosphere so we could eventually observe it.”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“We can assume, and there's evidence that it's uniformly distributed. Yes. So then the next, so all of these factors so far, number of stars accessible to whatever telescope you're thinking about, how many stars are quiet, fraction of stars that are quiet, fraction that are observable, in this case for the geometric factor. Those are all things we can measure. And there's one more term in the Sieger equation we can measure. I call it fraction of planets in the habitable zone. Because believe it or not, we have a handle on that for a certain set of stars. We know from the Kepler space telescope that operated for a number of years. We have estimates for how many planets are in the so-called habitable zone of the host star for a certain type of star. So all those we have measurable and then like the Drake equation itself, there are some terms we can not measure. And those ones, I call them FL, fraction of all those planets that have life on them.”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“Sun is So I have actually two terms. One describes how quiet they are, and one is if we can find a planet around that star. These transiting planets, for example, not all planets transit because the planet would have to be orbiting that star in this kind of plane as viewed from you. If a star is, for example, orbiting in the plane of the sky, it will never transit. It will never go in front of the star In that case, we have to have a fraction that takes into account that kind of geometric factor.”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“Yeah, but let's just say that out of all the stars there are accessible to whatever telescope, some of them are just bad for whatever reason. You're not going to be able to find planets around them. So I need to know the fraction of those that are good. So again, we have the number of stars, the fraction of them that we can actually find planets around.”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“Trillions and trillions of stars everywhere. It's what are available to like a specific search. And so, for example, the MIT-led NASA mission test is surveying the sky, looking for all kinds of planets, but it can also has stars. It has about 30,000 red dwarf stars. So we just take a number of stars that a given survey can access. So that's what the number of stars is. Then I wanted to know what kind of stars are quiet. I called it fraction of those stars that is quiet. In the case of tests, the way it's looking for planets is planets that transit the star. They go in front of the star, as seen from the telescope. But it turns out that some stars are very active. They're variable, and they brighten and dim with time. And that interferes with our observation.”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“So, in my equation, I set out to what are the numbers of inhabited planets that show signs of life by way of gases in the atmosphere that can be attributed to life. I could just walk through the terms. It's simpler. The first thing I say is what are the number of stars available? And it's not that”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“Oh, yes, the equation proposed numbers, and you can still plug your own numbers in. And there's this really cute website that lets you, for both the Drake and my revised equation, plug in some numbers and see what you get.”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“So I took the Drake equation and I called it a revised Drake equation and I recast it for the search for planets by more traditional astronomy means. We're looking at stars, looking for planets, looking for rocky planets, looking for planets that are the right temperature for life, looking at Looking for planets that might have life that outputs gases that we might detect in the future. It's the same spirit of the Drake equation. It's not going to give us any magic numbers. It's not going to say, hey, here's exactly what's out there. It's meant to kind of guide of where we're going.”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“Sure, well, the Drake equation, as you said, it's a framework. It's a description of the number of civilizations out there, of intelligent beings that are able to Communicate with us by radio waves So, if you think of the movie Contact, you've seen contact, right? We're hoping to get, we're listening in, actually. It's an active field of research, listening to other stars at radio wavelengths, hoping that some intelligent civilizations are sending us a message. And the Drake equation came like at the start of that whole field to put the factors down on paper to sort of illustrate what is involved to kind of estimating. And there's no real estimate or a prediction of how many civilizations are out there, but it's a way to frame the question and show you each term that's involved.”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“So, the funny thing is one time I met Frank Drake and I asked if he minded if I took his equation and kind of revamped it for this new field of exoplanet astronomy. He was totally cool with it.”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“But it sounds cool appears to have a planet around it. That's an about an Earth-mass planet in the so-called habitable zone, or the Goldilock zone of the host star. So think about how incredible that is, like out of all the stars out there, even the very nearest star, has planets and has a planet of huge interest to us.”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“But one thing that's really exciting in this field is that the very nearest star to Earth called Proxima Centauri is part of the alpha centauri star system.”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“After you interrupt your reverie and get back to in our lifetime at least the short term We have to, we only have the nearest stars to look at. It's true that there are so many stars, so many hosts for planets that might have life. But in the practical question of will we find it, it has to be a star quite close to Earth, like a few light years, tens of light years, maybe hundreds of light years.”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“Big pictures. Doesn't mean that big picture is. Yes, I believe absolutely there is life out there somewhere because the vastness of the universe is incredible. It's so breathtaking. When we look at the night sky, if you can go to that dark sky, you can see many, many hundred or even if you have good eyesight and you're somewhere very dark, you could see thousands of stars. But in our galaxy, we have hundreds of billions of stars. And our universe has hundreds of billions of galaxies. So, think about all those stars out there. And even if planets are rare, even if life is rare, just because the number of stars is so huge, things have to come together somewhere someplace in our universe.”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“Right, right. That's exactly what we need to do. And I like the word you chose hint because it's going to be a hint. It's not going to be a 100%, yay, we found it. And then it will take future generations. To do more careful work to hopefully even find a way to send a probe to these distant exoplanets and to really figure this out for us.”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“Right, right. And there's a difference, right? If it's 10 years or 20 years or 100 years, yeah, there's a difference in that. Soon could be a decade or two decades. Way journalists usually don't like that, or the people want tomorrow, they want the news, but what it's going to take is telescopes, space telescopes, or very sophisticated ground or space telescope telescopes to let us study the atmospheres of other planets far away and to look what's in the atmospheres and to look for water which is needed for life as we know it, to look for gases that don't belong that we might attribute to life. So we have to do some really nitty gritty astronomy.”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“Yeah, we naturally resist that because we want numbers and hard facts and not speculation. But I do love that question. It's a great question. And it's one we all wonder about. But I have to give you the scientist's answer first.”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“Lex, the funny thing is that as a scientist, I so don't even want to answer that. I will answer it though. But I just love to say”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“Think as a child without articulating it, I felt that same way. Just like, wow, this is terrifying. What's out there? Like, what is this? What does it mean about us here?”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“The Dark Knight Sky and all those stars just like screaming at me. I just couldn't believe that. Honestly, my first thought was this is so incredible, mind-blowing. Like, why wouldn't anyone have told me this existed?”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“I do have this very incredible distinctive memory. And again, it had to do with my dad. He took us camping. Now, my dad was from the UK, and he was the type who you'd find wearing a tie on weekends. So camping was not in his sphere, his comfort zone. But we had a babysitter. Every summer we got every summer we had a babysitter. And one summer we had Tom. He was barely older than we were. He was 14. My brother was 12. I would have been 11 or 10 maybe. And we went camping because Tom said camping's the thing. Didn't aim to see the stars, but I walked out of my tent in the middle of the night, and I looked up. And wow, so many stars.”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“I think it's hard to say. I had this book when I was a child. It was in French. I grew up in Canada where French is supposedly taught to all this English-speaking Canadians. And it was this French book in French, but it was about the solar system. And I just loved flipping through it. It's hard to say how much, you know, you or I understand when we're kids, but it was really a great book.”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“It's hard because we live in our frame of reference here on this planet. Nearly impossible. None of us are lucky to go to see the curvature of Earth.”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“That age, like age five, there's just no way you can. I think it's one of the great things about being a kid, it's just that curiosity that all kids have.”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source
“I think I've always loved the stars. One of my first memory is of the moon. I remember watching the moon, and I was in the car with my dad, who my parents were divorced and he was driving me and my siblings to his house for the weekend. And the moon was just following me, just had no idea why that was.”
2020-08-16 · Lex Fridman Podcast · #116 – Sara Seager: Search for Planets and Life Outside Our Solar System · IDENTIFIED FROM THE TRANSCRIPT · source