Are We Alone In The Universe? Sara Seager on Exoplanets, Venus, and the Hunt for Alien Life (Astrophysicist and Planetary Scientist at MIT)

Why search for life beyond Earth? For MIT astrophysicist and MacArthur Genius Fellow Sara Seager, it’s not just a scientific question—it’s a deeply human one. Like creating art or studying philosophy, the search taps into our primal curiosity about who we are and whether we’re alone. Sara is a pioneer in the field of exoplanets: planets that orbit stars other than our Sun. Her early work was met with skepticism. Today, she’s one of the most respected voices in the field, with discoveries that have redefined our understanding of the universe. From detecting alien atmospheres to reimagining where life might exist, she shares how entrepreneurial thinking and intuition are fueling groundbreaking discoveries. In our conversation, we explore: • An explanation of exoplanets and the importance of their discovery • The key technologies that enabled exoplanet detection • Sara’s controversial discovery of phosphine gas in Venus's atmosphere and why it could be a sign of life • An overview of Project Starshade, why NASA has currently shelved it, and why Sara continues to work on it anyway • How scientific innovation often requires challenging authority and conventional wisdom • How Sara approaches her research portfolio like an investment strategy, but with an inverse risk profile • Why AI may someday explore planets we’ll never reach—and what that means for humanity • Much more! — For a full transcript of the episode, please visit: https://www.generalist.com/p/are-we-alone-in-the-universe-sara-seager — Thank you to the partners who make this possible Augment Code http://augmentcode.com/generalist: AI coding assistant that pro engineering teams love. Brex https://www.brex.com/mario: The banking solution for startups. — Timestamps (00:00) Intro (04:07) What is an exoplanet? (04:33) The diverse types of exoplanets, including the common Sub-Neptune type (06:40) Why the search for habitable planets matters (08:57) The timeline for finding life outside of Earth (10:15) Parallels between professors and entrepreneurs (11:37) Sara’s background and inspirations (15:48) Why the study of exoplanets was initially viewed with skepticism (18:38) Technology breakthroughs enabling exoplanet discovery (21:05) Looking for atmospheric signals as signs of life (25:48) The K2-18b debate and challenges of detecting life (31:10) The Venus Life Finder Initiative and phosphine discovery (37:38) The mission to explore Venus's atmosphere (39:20) Goals of the first missions and the inspiration from a prior Soviet balloon mission (41:58) An overview of the Starshade project (47:44) Applications from the Venus mission that may benefit Earth (48:50) Sara's scientific "investment portfolio" and the impact of the MacArthur grant (52:46) The power of intuition (56:09) Formative lessons from Sara’s childhood (59:04) How Sara uses AI for administrative tasks (01:00:38) The evolution of AI (01:01:50) Sara’s speculation on life beyond Earth (01:03:24) Where Sara's best ideas come from (01:04:02) Final meditations — Follow Sara Seager LinkedIn: https://www.linkedin.com/in/sara-seager-1352b85/ Website: https://www.saraseager.com/ — Resources and episode mentions —Books— • The Smallest Lights in the Universe: A Memoir: https://www.amazon.com/Smallest-Lights-Universe-Memoir/dp/0525576258 • The Giver: https://www.amazon.com/Giver-Quartet-Lois-Lowry/dp/0544336267 —People— • John Bahcall: https://en.wikipedia.org/wiki/John_N._Bahcall —Other resources— • Exoplanets: https://science.nasa.gov/exoplanets/ • Sub-Neptune: https://en.wikipedia.org/wiki/Sub-Neptune • NASA’s Asteroid Bennu Sample Reveals Mix of Life’s Ingredients: https://www.nasa.gov/news-release/nasas-asteroid-bennu-sample-reveals-mix-of-lifes-ingredients/ • Seager Hair Transplant Centre: https://www.seagerhairtransplant.com/ • Kepler: https://science.nasa.gov/mission/kepler/ ... Resources continued at: https://www.generalist.com/p/are-we-alone-in-the-universe-sara-seager — Production and marketing by penname.co https://penname.co/. For inquiries about sponsoring the podcast, email [email protected].

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:00Speaker 00

  My favorite planet is always the next one because no matter how comfortable we get with the craziness that exoplanets are, there's always something even more incredible just waiting to be found. When people found the first exoplanets, nature was kind. Nature gave us easy to find planets. Like, if we had been left with all those solar system copies alone, we might not even be talking right now.

• 0:18Mario Gabriele?

  We have our own set of recipes for life on Earth, and some other species or civilization on another planet has these different set of recipes, and they could conflict so aggressively that you could effectively wipe each other out.

• 0:30Speaker 00

  There's just so much more out there, and we have evidence for hundreds of billions of galaxies out there. So if you just think about that for a moment, it's absolutely overwhelming.

• 0:43Mario Gabriele?

  Hey, I'm Mario, and this is the Generalist Podcast. You've probably heard the saying, "The future's already here, it's just not evenly distributed." On this show, we explore that future through conversations with the founders, investors, and thinkers who are already living in it, helping you see it more clearly and capitalize on what's next. Today's episode is especially futuristic. I'm speaking with Professor Sarah Seager, an astrophysicist at MIT and one of the world's leading experts on exoplanets, planets that orbit stars other than our own sun. As well as teaching at MIT, Sarah is a MacArthur Genius Awardee. She's responsible for changing how we search for life beyond Earth and pioneering

• 1:24Mario Gabriele?

  techniques to detect atmospheric signals from planets hundreds of light years away. In our conversation, we discuss the revolutionary hunt for extraterrestrial life forms, including how Sarah's team may have detected signs of life on Venus. Sarah's investment portfolio pokes to research, and how she balances a mix of high-risk and low-risk bets. And finally, the future of interstellar exploration, why AI might make it to other galaxies while humans remain confined to our solar system. I walked away from this conversation with an expanded sense of what's possible in the search for life, and how close we might

• 2:03Mario Gabriele?

  be to answering one of humanity's most profound questions: are we alone in the universe? This is a new podcast, so if you like it, I hope you'll consider subscribing and leaving us a review. Now, here's my conversation with Sarah Seager.

• 2:20Mario Gabriele?

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• 3:03Mario Gabriele?

  Keep using VS Code, Jet Brains, Android Studio, or even Vim. Don't hire an AI for vibes. Get the agent that knows you and your codebase best. Start your 14-day free trial at augmentcode.com/generalist. Sarah, it's really lovely to have you here today. And as a perhaps bit of preamble, this is a podcast about the future. And often I sort of interpret that in a slightly narrower sense through the lens of technology. But as I started to think about it on a more cosmic scale, I was acquainted with your work looking at planets outside our solar system and for planets that might have habitable life on them. And it was through that that I read your really remarkable memoir,

• 3:47Mario Gabriele?

  The Smallest Lights in the Universe, which is such a poignant story and also just, I think, an incredible scientific story. And so I say all of that just to say that I'm extremely excited for this conversation, but certainly a novice, albeit an enthusiastic one. So thank you so much for being here.

• 4:06Speaker 00

  Thanks for having me.

• 4:07Mario Gabriele?

  Just with the idea of bringing everyone along with us in this conversation, maybe we can start very simply with a few definitions. In basic terms, what is an exoplanet?

• 4:19Speaker 00

  Well, an exoplanet is a planet that orbits a star other than our sun. All those stars in the skies are suns. And if our sun has planets, it makes sense that the other stars have planets also. And they do. And we now know of thousands of planets, and there are probably trillions more out there.

• 4:34Mario Gabriele?

  I was surprised that I think NASA has a counter that we're nearing 6,000 detected exoplanets. Is that right?

• 4:42Speaker 00

  That's about right, correct.

• 4:43Mario Gabriele?

  And one of the things that struck me about it was just like our sense of the diversity of these planets, if you haven't spent time studying them, is really pretty mind boggling. Like, you know, two suns, raining glass, you know, seas of molten lava. Are there favorites that you have that sort of demonstrate that level of diversity that we're talking about when we talk about these types of planets?

• 5:07Speaker 00

  Well, all those you mentioned and more. My favorite planet is always the next one, because no matter how comfortable we get with the craziness that exoplanets are, there's always something even more incredible just waiting to be found. But if I had to pick one, it's this really odd type of seemingly bland kind of planet called a sub-Neptune. There are planets that are in between the size of our Earth and our Neptune, and we have no solar system counterpart, yet such kinds of planets appear to be the most common in our galaxy. But they're this kind of very average run-of-the-mill. It's like, here on Earth, you know, if you see a baby, you know they're a baby. If you see a super old, like 100-year-old, you can guess that they're very ancient. But sometimes there's that

• 5:48Speaker 00

  giant range in between, when, from afar, anyway, you know, perhaps like a 25-year-old to a 50-year-old, you might not, you know, from far away, they're moving, they are about the same height. And so these planets could be a lot of different things. Just like that age range, you could have, you know, a very young 25-year-old, you could have be like a cancer-stricken 50-year-old. But in general, we don't know what they are, and there's nothing like them in our solar system. And we're being on the verge of being able to find out what they might be like.

• 6:13Mario Gabriele?

  Oh, fascinating. So these sub-Neptune planets, it's almost, because they're so common elsewhere, it's almost anomalous that we don't have something like it in our solar system. Is that right?

• 6:21Speaker 00

  Right, right. And the flip side of that is, we haven't found any solar system copies yet. So it's kind of strange to think we might be rare.

• 6:29Mario Gabriele?

  Wow, fascinating. I think you have a good phrase in the book, which is that, for exoplanets, anything is possible under the laws of physics and chemistry, which I thought was, yeah, a good way of sort of stretching the imagination of what might be out there. At risk of asking perhaps a silly question, what is it about the search for habitable planets that has mattered so much to you? And why should other folks care about it as much as you do, or at least to an extent that they pay attention to this? You know, on one hand, it's clearly a massive cosmic question, but on the other, you know, What is the civilizational value of knowing that there are quasi phytoplankton 100 light-years away?

• 7:11Speaker 00

  Well, that question I cannot answer. We all have our own things that we're passionate about. And just like most people can't answer why they care about something. One thing we can say is that in a society where we have explorers or we have great art and music, we should add, what is the value of those things? So to me, it falls in that general category, number one. And number two, we sometimes make a giant discovery that is so value to civilization. That's the whole point of pure science. That's like GPS. I can't imagine there's a single listener who doesn't use navigation on their phone.

• 7:45Mario Gabriele?

  Yes.

• 7:45Speaker 00

  And do you think we set out to like, hey, let's figure out a way we can get navigation? No, we didn't. There were people fooling around with rockets, people trying to understand the night sky, which is a reference frame, by the way. But actually, the real value in astronomy and the search for life beyond Earth, it's actually getting more young people, mostly kids, into the hard sciences. I mean, now there's a real job crunch. It's May 2025, our graduates don't have jobs. But you know, the only place that does have jobs actually is defense. So we can ask ourselves, what is the value of astronomy? It's encouraging people to go into science because the sky is for everyone. And let's just face it, everyone wants to meet an alien of some kind.

• 8:21Mario Gabriele?

  Yes, that's definitely true. Just on that thread about the sort of job crunch, there's just not enough jobs out there for an astrophysicist or an astrobiologist?

• 8:30Speaker 00

  No, no, no, it's not that. I'm not even talking about that. I'm talking about biochemistry, computer science. I'm talking about tech and science in America today with all of the major funding cuts.

• 8:40Mario Gabriele?

  Yes.

• 8:41Speaker 00

  To university researchers. We're now seeing a cascade where overqualified people that are leaving university or not going to university are taking those very entry-level jobs that our undergraduates would normally be taking as they step into their life beyond school.

• 8:55Mario Gabriele?

  Got it. That makes sense. One of the things that struck me about your work on exoplanets and reading about it more broadly was the idea that actually the hunt for life outside of us is maybe not as far away as we imagine. I think you've maybe said elsewhere that in the next 10 to 20 years, we might have an answer on this. Is that sort of still roughly the timeline you think makes sense for knowing what's out there reasonably?

• 9:22Speaker 00

  Well, yeah. Well, funnily enough, we always put it about 10 to 20 years away. It's a bit of a hedge, if you will. But I think it's possible. Everywhere we look in astronomy, we see the ingredients for life. There's an asteroid, Bennu, that NASA just brought a sample back to Earth not too long ago and have recently completed the first very, very in-depth analysis. And they found all kinds of biological building blocks, many, many amino acids. They found our nucleic acid bases, so much exciting things. So we just see the ingredients for life in the interstellar medium, this very rarefied space between stars to, you know, we look at planets in our solar system and moons,

• 10:03Speaker 00

  we see like organic material. So it seems logical, right, that there should be life somewhere, even just very simple life, like microbes. And I do think there's a great chance of finding signs of it soon.

• 10:15Mario Gabriele?

  Incredible. Well, I'd love to get into sort of the progress around exoplanets as a field, which, you know, really charts your journey. But to take it a step even further back, your personal story that you talk about in The Smallest Lights in the Universe and your upbringing, I wonder if anyone has ever told you how many traits you seem to have that also mirror many of the great entrepreneurs. As someone who, you know, spends their time focused on tech and venture capital and studying these founders, you often see some extent of a quite difficult childhood, some amount of neurodivergence, like obviously extremely high IQ. And I wondered if that had ever occurred to you.

• 10:58Speaker 00

  In fact, that hadn't. So, thank you for that insight. But we do know that being a professor and being an ambitious, successful one is like an entrepreneur, because I am here working hard. My job is to educate undergraduates, to train graduate students, to do some outreach. But I really want to do science, but I need to get all my own money for science. I'm not paid for that. I'm paid, which makes sense, right, to help run the university, to teach.

• 11:20Mario Gabriele?

  Yes.

• 11:21Speaker 00

  So, I have to always be trying to get money, selling my ideas, hustling, implementing a great idea, right? Because that's what sets apart successful entrepreneurs just from those of others who have a great idea but can't quite make it work, or sell it, or make big bucks off it. So, that's really interesting. Thanks for sharing that.

• 11:38Mario Gabriele?

  Yeah, no, it's fascinating to me. And that also struck me about your career, like, to what extent you have been an extremely entrepreneurial academic with the different projects you've taken on, you know, clearly beyond just theory and executing a lot of these big ideas that we'll talk about. But your father was also an entrepreneur in a totally disparate field, but was also clearly a very important inspiration to you. And yeah, I was curious how often you maybe think back to him, or the advice that he gave from your childhood as you do this kind of work today.

• 12:11Speaker 00

  I definitely think a lot about him. In fact, it may be a bit TMI, but you have a very nice hairline.

• 12:17Mario Gabriele?

  Oh, thank you.

• 12:18Speaker 00

  My dad was a, he broke out into being a hair transplant doctor. He was a GP for like, say, 30 years. He started in a really small town, and he did everything. He delivered babies. He did psychology appointments. Those babies grew up, and he was their doctor. And after a while, we all want to do a new job after two or three decades. And he had always wanted hair. He lost all his hair by age 19. People thought he was the senior doctor when he went around doing rounds. And so, he did branch out. He asked some of his patients to be volunteers. One summer, I helped him. I happen to know a lot about it. And one thing they tried to do is make the hairline very natural, so that, you know, you can't have hair down to like halfway down your forehead. That's unnatural.

• 12:54Mario Gabriele?

  Yes.

• 12:54Speaker 00

  And nor do you want to get a hair transplant too early, because as your hair keeps falling out, then it'll just look weird later. So, there's a lot of aesthetics. He did invent new things in that field. But the most memory I have that he taught me was how to think big.

• 13:11Speaker 00

  How to make a plan and how to execute. I mean, he didn't give me like the step by step guide, but it was just like things here and there. Like one time, believe it or not, I came to MIT at a relatively young age with tenure. That's a big, big deal. And I was trying to explain to my dad what a big deal it was. And instead of saying, great, honey, that's so great. He didn't say that. He said, Sarah, no, I never want to hear you be limited by your own thinking. And what a surprise.

• 13:38Mario Gabriele?

  Yeah.

• 13:39Speaker 00

  I was just trying to say like, yeah, it's really great. I'm proud of myself. And wow, that definitely has stayed with me because you're right. Like there's, he just left me with, there's always a better job and someday you'll get it. And he was asking me to own that attitude.

• 13:52Mario Gabriele?

  I, I really love that response. And it's something that I've noticed in a lot of exceptional people that at some point in their life, someone served as sort of an ambition amplifier for them that just told them in some small way, like you can be happy with whatever you've done, but you know, do not be content and really push much further than you might be imagining.

• 14:13Speaker 00

  And also, you know, the other thing is it's really up to the individual to recognize that moment and to own it. I had another experience like that once where my postdoc mentor, John Bahcall, a giant in science, he also, he was like a father to me and he also threw out these random things. It was like, you can take it or leave it. And one time I just, I don't know where it came from, but I summarized his way of thinking is, if you have a great idea and you can back it up with physics and it's achievable sometime in your lifetime, which is a very long time. If you have a great idea, you can back it up by physics and it's achievable sometime in your lifetime. It is worth pursuing.

• 14:50Mario Gabriele?

  Hmm. Wow. That's a good, that's a good framing. Gosh.

• 14:54Speaker 00

  And I hope you can take that as well.

• 14:55Mario Gabriele?

  Yes, totally.

• 14:56Speaker 00

  What is ahead of you? You have decades ahead of you and you know, you're here now, but we should all think about that for a moment. What does that mean? Like a lifetime is a long time. And if you can back up the idea and you have, you know, your intuition, you have judgment, you have risk analysis. Like, let's do it.

• 15:12Mario Gabriele?

  Do you find that the work that you do sort of innately or naturally helps you think along longer time spans than, than most other people?

• 15:24Speaker 00

  Like yes and no. I think it really is a personal thing because I do meet other scientists. And given the choice between a long lead time, possibly like high impact work, or a very short lead time, another paper that can count on your resume towards your promotion. They're always going to pick that short term. So I don't think so necessarily.

• 15:44Mario Gabriele?

  Yeah, it's not necessarily about the space as much as it is about the person. On the subject of your scientific mentors and this field, what struck me so much in your memoir, or one of the many things, was just to what extent the study of exoplanets was seen as like, an incredibly unpromising field when you were starting out in it. Why was it looked down on so much?

• 16:12Speaker 00

  Well, two things. One is there's the giggle factor. Have you ever told anyone in your family or friend circle, hey, I'm going to do this?

• 16:18Mario Gabriele?

  Yeah.

• 16:19Speaker 00

  And they laugh. I mean, well, hopefully they're not laughing. You want to have your supportive group of friends, but there's always some people there. You can tell they're trying not to laugh or they're like that.

• 16:26Mario Gabriele?

  Yes.

• 16:26Speaker 00

  And what is, what kinds of things are those? Those are crazy things that are hard things that seem unachievable by anybody, not just you personally. And so let's talk about exoplanets. It makes sense that planets are out there. Our sun has planets. We already had seen stars being born, surrounded by discs of gas and dusk. We knew they had to be making into planets. Just like those dust bunnies under your bed, they're going to form. You can't help it. So we had to, we had to be sure at some level they were there. But finding them was a whole other thing because planets are tiny compared to their bright, massive host stars. So it's not that we'd be bad at finding astronomy. We can find small faint things, but not when they're right next to a big, bright, massive star.

• 17:09Speaker 00

  And so the kind of giggle factor, the kind of not believing, thinking it was a bad idea was simply because it's too hard, too challenging.

• 17:17Mario Gabriele?

  So it was less that people didn't think it was possible, more just that people thought you'll never, you'll never be able to do it practically?

• 17:25Speaker 00

  Yes, it was, let's just rephrase that a bit. It's, it's people believed the planets were out there. They had to be. They just thought it was not necessarily, not possible to find more than a handful of them.

• 17:38Mario Gabriele?

  Yes. And an intellectual dead end to spend your life on it.

• 17:42Speaker 00

  Yeah, an intellectual dead end because, and this resistance was there for a very long time. When people found the first exoplanets, nature was kind. Nature gave us easy to find planets, big planets, Jupiter mass planets, very close to their star, like nearly 10 times closer to their star than Mercury is to our sun. And by the initial methods, that happened to be very easy to find those. Like if we had been left with all those solar system copies alone, we might not even be talking right now. So initially, once we had a handful of planets, you know, eventually people started to agree they were real, but they still thought the field would dead end. Because people didn't think that the detectors or the telescopes or the techniques, but you know, who forced, you know, and now looking back, of course, hindsight is 2020.

• 18:26Speaker 00

  You could say, you know, we have really, really great detectors now, like the camera on your phone is just incredible. We have great detectors, we have great this, we have great that, we have AI, we have computers. Everything has been rushing along.

• 18:39Mario Gabriele?

  And, and on the technology piece, you know, obviously, exoplanets is, the, the rise of it as a, as a field of study has been driven by people like you, but also it is in, in some respect, a technology story, as you mentioned. What were sort of the major unlocks that allowed for, you know, 1992, I think is when they, you know, the first exoplanet is detected and now to be almost 6,000 of them catalogued. What allowed for that?

• 19:06Speaker 00

  Well, I'd say it's two things. I mean, there's way more than two things. One is computer power. What I had heard was for the initial set of exoplanets, the ones around sun-like stars, which started in 1995, we have a lot of spectral lines, like when we take the light from a star and split it up into its constituent colors, there are like thin, like lines of absorption of gases in the star's atmosphere. And we're using those to, well, it's a bit technicality, but we're measuring the Doppler shift. Those lines are moving back and forth as the star is wobbling due to the planet orbiting it. But one of the limitations was getting enough information out of the data. And that was because a lot of these lines are blended together. They're overlapping. So having the computer software to sort through all that was a ginormous breakthrough.

• 19:52Speaker 00

  The second thing was detector technology. I think that's probably true in so many fields. But a long time ago, when I started out as an undergrad, we had these things called photomultiplier tubes attached to a telescope where you could record the brightness of stars and the variation. But what was just coming online were CCD detectors. And those have developed so amazingly well. They're very sensitive and you can make much, much more precise measurements. And that's what we needed to find the tiny signals. So that coupled together with space above the blurring effects of Earth's atmosphere, enabled NASA's Kepler Space Telescope, you know, to get up there, get launched. And this was back in 2009, and just find absolutely astonishing populations of planets.

• 20:37Speaker 00

  So it's those two things, just the speed of computers enabling software to break through all the issues and then detector technology.

• 20:45Mario Gabriele?

  And, you know, you'll have to forgive me, but what is a CCD detector? What is that actually, you know, doing?

• 20:51Speaker 00

  Well, it's just called a charge coupled device. And in general, it just gives you like real estate. So you can look at lots of stars at one time rather than like a more narrow field of view where you're measuring the brightness in a more kind of clunky analog way.

• 21:05Mario Gabriele?

  Fascinating. I really enjoyed sort of the detective work of trying to identify these exoplanets. And you have a nice metaphor in the book of, you know, you're essentially looking for Bigfoot by looking for his breath, by looking for these sort of atmospheric signals. You've, you've talked about it a little bit there, but yeah, to the extent that you're able to let listeners into, to that idea, like when you, we talk about the breath that we're looking for, what are, what are you actually seeking out?

• 21:34Speaker 00

  Sure, well, let's back up a little bit. We talked about detecting exoplanets, but observing their atmospheres is like a whole other level of hardness because, you know, your planet is so big, but then the atmosphere is like the skin of an onion on an onion. It's just kind of like the very outer layer. It's very hard to detect, but the atmosphere can tell us a lot about the planet. Like our planet Earth, we have oxygen in our atmosphere that we humans need to breathe. We need oxygen to survive. Yet, without life, without plants and photosynthetic bacteria, we would have no oxygen in our atmosphere. You know, we have a lot of carbon dioxide, we have greenhouse gases, other greenhouse gases too. So the atmosphere is really complex and it's tied into the, at least the interior and the oceans.

• 22:16Speaker 00

  So we want to learn about the atmospheres, just to learn more about the planets in general, and eventually to search for signs of life. So that's kind of what the atmospheres are. I mean, that's what we mean by it, is we want to find the gases that are present, so we can kind of pick apart what's going on there.

• 22:32Mario Gabriele?

  And it's sort of a, you know, looking for these biological signals, sort of contrasts with, I think, a lot of what people's maybe common perception of how you search for extraterrestrial life, which is more of these techno signals, sort of looking for radio communications and things like that. For those that maybe haven't dug into the space, why is this like proven to be just a much more productive pathway so far?

• 22:56Speaker 00

  Well, because most planets have atmospheres, and most planets do not have intelligent life to send us a signal. But let's hold on to that thought for a moment, because whether or not looking at the atmospheres is the best way to find a definitive sign of life, you know, that is still debatable.

• 23:15Mario Gabriele?

  Yes, and you talk in the book about, you know, in some ways, the atmospheric conditions that we assume lead to life on Earth and so on. You can almost be too terra-centralist, I forget the phrase you used.

• 23:30Speaker 00

  I use the phrase terra-centric.

• 23:32Mario Gabriele?

  Terra-centric, thank you. In looking for these signals, because we really don't know how life might form in a different set of conditions. And you have this amazing thought experiment about if two different civilizations were to meet, they might poison each other because of their specific conditions. And I wonder if you might sort of share that example, just to sort of frame it up for folks.

• 23:57Speaker 00

  Sure. Well, in exploring chemistry, we, my team, went off on a big side chain. And we started to notice that there are some bonds or some fragments of molecules that our life just avoids, actually. It's kind of surprising because if we were to enumerate all of the elements in life's products, so stuff life makes, well, there's a lot of nitrogen and a lot of sulfur. But what's so unusual is a nitrogen sulfur bond appears to be nearly absent from Earth's biochemistry. So it's so weird. We have a lot of nitrogen, we have a lot of sulfur, but nitrogen and sulfur bonded together within a molecule, it just seems to not really exist.

• 24:37Speaker 00

  I mean, there are a few rare exceptions. So what we noticed was, well, we did some experiments and we concluded that what's really interesting is molecules with nitrogen sulfur bond are incompatible with a much more common type of bond and that our life uses sulfur hydrogen bonds. It sounds a bit esoteric, but let's just say life couldn't use everything available to it. It's like doing a recipe, you know, some things just do not go together.

• 25:02Mario Gabriele?

  Yes.

• 25:03Speaker 00

  So in the book, I was just trying to explain it by a height, an imagined scenario where an alien, it's not going to happen, but imagine an alien comes to Earth, but their biochemistry chose to use the opposite, chose to use those nitrogen sulfur containing molecules bonded, you know, nitrogen sulfur bonded within a molecule and we never use that. And if we met each other and shook hands, it was all great. Wow, we might just poison each other because our bodies cannot handle that.

• 25:30Mario Gabriele?

  You know, we have our own set of recipes for life on Earth and someone else or some other species or civilization on another planet has these different set of recipes and they could conflict so aggressively that you could effectively wipe each other out.

• 25:45Speaker 00

  Exactly. We definitely could.

• 25:47Mario Gabriele?

  Fascinating. On the, the sort of returning to the subject of looking for these atmospheric signals, I'm curious to understand, to the extent that you're able to share, what are the places where it's, you get sort of most false signals or the most errors of when you're trying to make these detections? How much of this is in flux whenever you are looking at some new exoplanet and trying to decipher what it is like and whether it's habitable?

• 26:13Speaker 00

  Well, it's extremely challenging. There's one right now. There's a planet that's being debated in the news and just last month, The New York Times wrote an article, astronomers detect a possible signature of life on a distant planet. Further studies are needed to determine whether K218b, which orbits a star 120 light years away, is inhabited or even habitable. So we can, you know, break that down briefly. K218b is one of these sub-Neptune sized plants I was talking to you about. There is a kind of It's kind of going away, but a paradigm that life needs water, liquid water. Now, what's really interesting about K218B is in its atmosphere, one gas we expect to be there, ammonia, NH3 is missing.

• 26:55Speaker 00

  And it turns out ammonia is very, very, very soluble in water. So we might think that might indicate there's a liquid water ocean there because, you know, gas got dissolved in it that should be in the atmosphere. However, it's also correct that nitrogen likes to dissolve in liquid rock. So the planet could have like a massive greenhouse atmosphere, causing its surface to have liquid lava lakes or oceans. So there's ambiguity for you. We don't even know if this planet, what it's like, like, is it a water world with a lot of water and liquid water? Or is it its massive greenhouse and no water and, you know, rock that's all liquid?

• 27:39Speaker 00

  So we don't actually know what's going on in the planet alone. Yet, one group has tried to claim there's a sign of life there by way of a gas that doesn't belong, that at least on Earth is not produced in any significant quantities other than life. And this is kind of like the very current thing. So if we listen to this interview 10 years from now, hopefully it'll all be water under the bridge by then. But right now it's undergoing debate for some very good reasons. First reason, is the signal real? People are arguing about whether the signal is real. You know, we have to do a lot of data analysis. I don't want to make the analogy to Photoshop, but it's like as if, you know, you have taken a photo with your phone and you're trying to enhance certain parts of it.

• 28:21Speaker 00

  And the question is, are you enhancing it so much that you're amplifying what's really nothing to something? That's the first question. The second question, if the signal is real, are we attributing that signal to the right gas? It's like, you know, if we have fingerprinted you and, you know, hundreds of thousands of other people, we can pick you out. But what if we can't see all five fingerprints? What if we only see a tiny slice of one finger? We might get it wrong just because, you know, there's a lot going on. There's a lot of fingerprints. So question number two, is it attributed to the right gas? We don't know that either. I think we can sort through those first two. We can get more data. We can do more considerations of other gases. But it's number three where we're going to ultimately be stuck.

• 29:02Speaker 00

  And that number three is if we believe the signal's real and it's attributed to the right gas. Number three is, is it made by life? Or is there another process on this planet? We don't know much about that is creating that without life.

• 29:15Mario Gabriele?

  And the reason we think, or these scientists, rather, who proposed that it might indicate life is because the signal itself is something that we only see created by, I think, marine life on planet Earth. Is that, is that right?

• 29:29Speaker 00

  That's right. Marine phytoplankton. But that, the group is led by one of my former students, actually. So I don't really like to say anything bad when he's not here to defend himself.

• 29:37Mario Gabriele?

  Yes.

• 29:37Speaker 00

  But the first two aren't true. So we, we probably shouldn't even talk about number three until we can settle on the first two. Is the signal real? Is it attributed to the right gas?

• 29:47Mario Gabriele?

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• 30:31Mario Gabriele?

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• 31:15Mario Gabriele?

  has maybe changed to some extent. What's been behind that shift?

• 31:20Speaker 00

  Well, what is behind that shift is a lot of my work because guess what? I was involved with a very controversial discovery of a sign of life on another planet, Venus, and this gas is called phosphine, which I know, just like dimethyl sulfide, no one has heard of it for good reason, because it's extremely rare. It's only produced by life on Earth. We make it as pesticides, or it's made by bacteria and oxygen-free environments. So I was involved with this. That's why I know so much about it, because I've lived through claiming a sign of life, at least reporting a gas on Venus that shouldn't be there, that is not made by any known process like lightning, or meteoric delivery, or volcanoes.

• 32:01Speaker 00

  And wow, we got really trashed in the scientific world because of those three things. One is the signal real. We had to do a lot of data processing to get our signal. Number two, is it attributed to the right gas? It looks like phosphine to our team, but others might claim it's sulfur dioxide, a gas that's already known to come out of volcanoes on Venus. But let's say those first two are true. Well, now can we really prove to you at 100% level that there's life on Venus? No, we cannot. And one of the arguments against it is that Venus has no water. Instead, it has a very nasty, nasty chemical called sulfuric acid, concentrated sulfuric acid. And it's not the surface we're talking about, by the way, because the surface of Venus is too hot for life.

• 32:47Speaker 00

  But just like on Earth, if you go on a mountain, climb up a mountain, or go in an airplane, it gets colder and colder. And 50 kilometers above the surface of Venus, it is the right temperature for life. And that's a cloud deck, like permanent clouds that are always there, and we have life in our clouds. So kind of, all that kind of makes sense. Maybe there's life, but it's not water, it's sulfuric acid. And that has even more of a giggle factor than are there exoplanets and can we find them? But bolstered and what's the word, like when you're brave now because of your past?

• 33:16Mario Gabriele?

  Yes, yes, you've sort of built the thick skin on it.

• 33:19Speaker 00

  Built the thick skin on it. We've decided to explore this in the laboratory. That's why I was running late today, because I have a chemistry lab now. I'm like an astrochemist. But my lab, because space is so at a premium everywhere in all universities, I have to walk 10 minutes to get from my lab to my office. So I was involved in some new, just yeah, doing some work in the lab. So what we've been doing is we've been studying, not life, because our life cannot survive in sulfuric acid, but we're studying biomolecules, like building blocks of life. This is a whole other thing. Like honestly, it's probably like an entire other, other podcast to get into the details, but it really is so much like the early days of exoplanets. No one believes it. No one really cares. And we're trying to

• 34:01Speaker 00

  cover as much ground as possible to like own this field and also in parallel, working on space missions to go to Venus to search for signs of life or life itself.

• 34:11Mario Gabriele?

  Okay. There was so much fascinating information there that I almost want to summarize it to make sure I'm following and also to lead us somewhere. You worked on this, it was called, I think, the Venus Life Finder Initiative, which is where you sort of detected this set of signals that we talked about, the phosphine gas. And I think what you were saying is that basically there is perhaps the conditions for life above the cloud cover on Venus and that that is what you are now investigating more deeply with regards to seeing what sort of building blocks of life can live in sulfuric acid? Did I, which parts did I butcher brutally?

• 34:50Speaker 00

  Well, what's interesting is you've got, you have a very, very, very logical narrative, but it happened in a slightly different order.

• 34:56Mario Gabriele?

  Okay, excellent.

• 34:57Speaker 00

  So I'll slow down. So I've been working on exoplanets for two or three decades.

• 35:02Mario Gabriele?

  Yes.

• 35:02Speaker 00

  Thinking about what gases might be made by life, came across phosphine, an amazing gas, very, very, very rare, made by life on Earth, seemingly only made by life on Earth. Got involved with a different team, not my team, trying to find signs of life on Venus, ironically, by phosphine.

• 35:20Speaker 00

  Join that team.

• 35:22Mario Gabriele?

  Yes.

• 35:23Speaker 00

  Reported phosphine on Venus with some room for it being possibly made by life. Use that opportunity to get the space mission group together to handpick individuals to carefully think through what can we do to find signs of life or life itself by going to the Venus atmosphere directly. Our sponsor, who gave us a little bit of seed money, asked us to do laboratory experiments to support the mission. And I'm like, wow, what? What kind of lab experiments? And then the lab experiments took an entire life of their own now with a growing number of biomolecules, stable and concentrated sulfuric acid.

• 35:59Mario Gabriele?

  Wow. So just to unpack that last piece, what does that mean to sort of like test the stability of these biomolecules? And what are the sort of signals that you're looking for or sort of hypothesizing you might come across?

• 36:11Speaker 00

  We started out very simply. We took our amino acids. Those are basic building blocks of life. You know how some muscle builders like to eat amino acids or amino acids, you know, come together to make proteins? We put our 20 biogenic amino acids that our life on Earth uses in sulfuric acid. And we were really surprised to find that, you know, with one exception, they're all stable. We literally just put it in and we have to do some sophisticated chemistry analysis to show that the molecules are not changing over time. Or if they are changing, like some of them do, they're still stable. We put other things like parts of our DNA. Our DNA is unstable, but we put some parts of

• 36:53Speaker 00

  them that are stable. And we've sort of been moving through the space of the molecules our life uses to find out which are stable and which are not.

• 37:01Mario Gabriele?

  Fascinating. And so the implication potentially there is that, you know, the presence of sulfuric acid doesn't rule out the possibility of there being, you know, life on Venus in the way that people maybe believed it to be the case.

• 37:14Speaker 00

  Yes. Yes, exactly. I love how you said that. And we are just trying to take this work far enough to motivate missions to Venus to search for signs of life or life itself. So we're not trying to like make a life form in sulfuric acid, right? We're just trying to convince people like you and everyone else and people who will fund the mission that it's wow, absolutely worth going there to do some really, really close up front investigation.

• 37:39Mario Gabriele?

  Wow. What does it take to get to Venus? Both in terms of sort of capital and technology?

• 37:45Speaker 00

  Well, the question is always more, what do you want to do when you get there? And we do have a series of missions to Venus. You know how before we were talking about the giggle factor and people being uncomfortable? People did not like the name of our missions Venus Life Finder Missions. So we did kind of back off due to peer pressure and we've rebranded to Morning Star Missions to Venus. The reason we picked that name was sometimes Venus is shining very brightly in the morning sky. And it's like a new dawn is rising for space missions, fast focused space missions. Typically, when you're doing a space mission, you have to have everyone on board in the community. There's many, many instruments because everybody has to get a part of it.

• 38:29Speaker 00

  But that really slows things down and makes them more expensive. So we're trying to do these missions through largely privately funded or private public partnerships. So we can stay focused and get the job done and work in this really extreme area that most people still don't believe in. So what does it take? It takes a lot. I mean, it takes working with a partner. We're working with Rocket Lab for the first mission. It's called the Rocket Lab Mission to Venus. That is on the same wavelength with this idea of something small, focused, simple. We don't want to use the word dumb. We sometimes do. You want to make it as dumb as possible, like few moving parts, few things that can go wrong. And get to Venus and each mission will build on the last. So we're not going to find life right away, but we want to be able to send more complex missions

• 39:14Speaker 00

  to find very complex molecules that are, you know, highly suggestive of life being there.

• 39:21Mario Gabriele?

  What would be the data that you would hope to collect? That would sort of move forward your, your understanding of Venus best? Like, you know, this is a very naive question, but is it sort of soil samples? Is it atmospheric samples? What is it that, yeah, would help the most?

• 39:37Speaker 00

  Well, right now it's atmospheric samples because if there is life on Venus, it's going to be in the temperature ranges that can support life. And those are high up in the atmosphere of Venus in the clouds. So ultimately, we'd like to go to Venus with a balloon mission. And you know, the former Soviet Union sent two balloons to Venus.

• 39:57Mario Gabriele?

  I did not know that. Wow.

• 39:58Speaker 00

  Yeah, in the eight, in the early eighties, they lasted a couple of days. In the old days, everyone would do two in case one didn't work, but they both worked. They had batteries and they lasted as long as their batteries did, which was a couple of days floated around. So we'd like to go to, I'm only telling you that so it doesn't sound as hard as it actually is.

• 40:15Mario Gabriele?

  I mean, that is, it's sort of amazing that I've never heard of that. Not because I, you know, know that much at all, but just because that seems like a sort of landmark achievement.

• 40:25Speaker 00

  So landmark. So that we want to send a balloon and collect cloud particles. We'd like to condense the cloud particles and then evaporate the excess sulfuric acid. And whatever's hopefully left over, hopefully there's leftover material. We will send that to a chemical analyzer called a mass spectrometer to identify complex molecules. And we have a plan. We're working on that. We have prototypes in the lab. We have a partner who's building the mass spectrometer in Berne in Switzerland. We have designs. We have a balloon vendor who's building us a flight like balloon this summer. So we're moving this whole thing forward.

• 41:02Mario Gabriele?

  Wow. Incredible. Uh, this is, I think, a really good case in point of, of sort of your career as an entrepreneurial academic. But one of the things that also struck me was you talk about the need to create sort of like cheaper, faster, faster, nimbler expeditions. And a big part of the exoplanet research you've done has been sort of relying on these cheaper satellites. And I, I'd love to hear, you know, how you thought of that modality and how it's sort of changed the way that we're able to gather data on exoplanets.

• 41:34Speaker 00

  A lot of the exoplanet work that now it's going to be a bit contradictory now because a lot of the

• 41:38Mario Gabriele?

  Oh, interesting.

• 41:39Speaker 00

  Things that did well, like the Kepler space telescope was not a cheap mission. It was a simple mission, though. It just had one goal. It had one payload, if you will. But Kepler was definitely not a cheap mission. So I think there's room for both, really complex things and really cheap things. But right now, we have to go for cheap and reasonable.

• 41:58Mario Gabriele?

  Fascinating. One of the projects that you've also worked on was something called Starshade, which really felt directly out of science fiction almost, which is sort of this incredible parasol almost in space. Yeah, I would love for people to hear about that project and where things are with it.

• 42:17Speaker 00

  This is a 1% scale of Starshade. It would be a giant specially shaped screen that would go to outer space. It would have a spacecraft attached to it and it would block out the starlight so only planet light can enter the telescope.

• 42:31Mario Gabriele?

  And by doing that, you're able to gather just much more precise or sort of you're able to filter out a lot more of sort of like the visual noise. Is that a fair way of saying it?

• 42:41Speaker 00

  Yes, well, the entire goal is to block out the starlight so we can see the planet light directly. Now, wait, before we leave that, I'm going to show you something else. That's a full scale.

• 42:51Mario Gabriele?

  Oh, wow, that's a full scale fin?

• 42:54Speaker 00

  Pedal, yeah, we call it a pedal. It's like five and a half meters long.

• 42:58Mario Gabriele?

  Wow, and for people who don't watch the video, it is a massive black pedal essentially. And I think there are 28 in the design, I can't remember.

• 43:09Speaker 00

  Yeah, there's different designs depending on how you want to sew and deploy Starshade. But back to what Starshade will do is, you know, there are very many ways to discover and study exoplanets. But the Starshade is very special because it falls into the category of finding a true Earth twin. Remember, our solar system is so hard to find, but we'd like to be able to go beyond the blurring effects of Earth's atmosphere to block out the starlight just to only get planet light in the telescope. And that's the goal of Starshade.

• 43:38Mario Gabriele?

  Fascinating. And what are the sort of next stages of Starshade that you hope will happen over the next decade or so?

• 43:47Speaker 00

  Well, right now, Starshade unfortunately has been kind of shelved by NASA.

• 43:52Mario Gabriele?

  Okay.

• 43:53Speaker 00

  And there's a competing complementary idea called the coronagraph, which blocks out starlight when it's inside the telescope. And that is what NASA is pursuing right now. But Starshade is such a great idea that it will survive. It'll have to get shelved for a while and get revived. But a group of us, we still work on Starshade. You can look at my website called projectstarshade.com. And keep up to date with what's new there. But I would like to take, well, I'm not sure if it's appropriate to do here, but I have a really good analogy for starshade. Let's imagine, okay, so the chronograph is like a starshade, but inside the telescope. And the advantage there is you don't have two separate spacecraft and two separate things going on because starshade has to block out starlight.

• 44:35Speaker 00

  And formation fly with the telescope, very far apart, very precisely. And so it's a lot of added cost to have an extra spacecraft to do all this formation flying. It's hard. So it may seem that having a device you put inside the telescope might be easier, but here's why it's harder. I want you to imagine that we're actually in the same room. And before we got started, you had brought me some banana bread.

• 44:58Speaker 00

  And I said, wow, I love banana bread, but here's the thing is I don't eat cinnamon. So I need you to go in that banana bread and pick out all the cinnamon one by one. It's hard.

• 45:07Mario Gabriele?

  Yes.

• 45:08Speaker 00

  I mean, let's say there's 10 billion parts flour to 1 billion parts cinnamon. That would be like the 10 billion photons from the star to every one photon from the planet. But let's say instead you told me in advance, hey Sarah, I'm going to bring some banana bread. And I'm like, that'd be great, but I don't eat cinnamon. Please keep that cinnamon separated and let's bring it and keep it separated.

• 45:31Mario Gabriele?

  Yes.

• 45:32Speaker 00

  So you've separated out the planet and starlight before we even started. Way easier.

• 45:37Mario Gabriele?

  Yes. And so it's the idea, you know, of, of having this telescope floating in space. Starshade is sort of, you know, the telescope is the eye. Starshade is sort of shading that eye's view in such a way and filtering out for you, with your analogy, the cinnamon, rather than sitting within the eye and trying to filter out after the fact.

• 45:58Speaker 00

  Yes. And after the fact, the problem is that the star and planet light all intermix together. Bounce around imperfections in the telescope. And then they get even more jumbled up, just like the cinnamon being all spread out in the banana bread. And it's just a very, very hard problem. Now, if we could solve that problem. It does seem a bit easier to have just one thing go up there instead of two, but we need to solve that problem before we can be sure it's going to work. And that's what NASA is trying to do with their so-called habitable worlds observatory.

• 46:27Mario Gabriele?

  Is NASA the only organization that is capable of taking this to the practical next step? Or do you see a role of the private sectors in these sorts of projects?

• 46:40Speaker 00

  That's a tough one because very, very hard problems require so much money. And it's really hard for, like the question we started out with, why are we doing this? Well, we're doing great art and great music and we're trying to inspire and know who we are. And that is something usually the government does. It's very hard for private investors. It's not really an investment because you're not going to get money back. In contrast, the Venus missions I'm telling you about, they're far cheaper. They're more than 10 times cheaper than Starshade, maybe 20 times cheaper, maybe even 50 times cheaper. And we are developing some technology that could have applications on Earth. So we have more of a concrete motivation if there are going to be investors. So it's definitely tricky. We'll see.

• 47:22Speaker 00

  It could be possibly that, for example, Europe or another country launches a telescope that we make sure is Starshade compatible. And that now our cost comes down and we could do something more cheaply. So it's all, like you said, the entrepreneurial spirit. We have a lot of things cooking, trying to keep things alive, moving forward. And when the time is right, we jump on the one thing we're trying to make real.

• 47:44Mario Gabriele?

  Yes. What are the applications from the Venus mission that might be sort of Earth applicable?

• 47:50Speaker 00

  Oh, well, great question. Well, I'm super, super excited about miniature molecular sensors. People are using these from all kinds of things, so like detect cancer to environmental sensors. And shrinking them down to tiny, tiny pieces means we could be able to, for example, instead of sending a big balloon with our mass spectrometer and collecting the clouds and evaporating it and all that, we could imagine just having a probe and as it's falling down. It could drop off a bunch of little mini sensors, or they could be attached to the outside of the probe. And as they hit the liquid, these miniature molecular sensors could pick up what they're looking for and send us a yes or no signal.

• 48:34Mario Gabriele?

  Hmm, so if you develop sufficiently good miniature sensors to detect, you know, this phosphine gas and other sort of signals on Venus, that is probably quite good for detecting lots of important things on Earth, too.

• 48:47Speaker 00

  It could be if we do it right.

• 48:49Mario Gabriele?

  Really interesting. In your memoir, you talk about your work as almost an investment portfolio, which I thought was really fascinating. You know, you have your sort of low-risk parts, your moderate-risk parts, and then, you know, a few very high-risk parts of the portfolio. When you look at your portfolio today, like, what does that balance look like? Which are the parts that are the true flyers that could be massive? And which are maybe the more sort of steady compounders?

• 49:15Speaker 00

  Great question. You know, for us humans, as we age, we're supposed to have less risky and more conservative, right? The idea being that as retirement looms, you want to make sure you're not going to lose all your money. But oddly enough, in science, my portfolio has gone the other way, into more and more extreme investments. It feels like the less time I have left to work, which is still a long time, but let's just face it, we're not getting any younger here, the less time I have, the more risky. So I'd say right now, it's probably 90, 95%. I'd say it's like 50% high-risk, 45% extremely high-risk, and maybe 5% kind of conservative-normal.

• 49:51Mario Gabriele?

  Wow, incredible. Did winning the MacArthur Grant help, like, change your risk profile at all?

• 49:59Speaker 00

  It didn't at that time because I was always working quite risky. But it actually more helped other people than it helped me because I already knew I was good at what I do. I already had my achievements in the past. But it let other people get the rubber stamp I think they needed to be OK with what I'm doing. And I had a really funny thing happen. It's sort of funny, but like one of the most helpful things was, I mean, the most helpful things were personal because it came with a lot of money. And at the time, I was a widowed, single mother. And I'd just become widowed a bit earlier. So I could use all that money to supplement, like, on the home front. Like, I could have my housekeeper. I could have my wonderful, wonderful family friends, who were nannies at the time. The funny thing is, my son just graduated from college, and we had a party for him. And he has a girlfriend, and her whole family was there. And her dad's like...

• 50:45Speaker 00

  Wow, there's a lot of nannies in your life. Because our four, well, three family friends who were their babysitters, who are very good family friends to this day. I think it was a bit confusing for him because I don't think he knew the whole story. It's sort of like, like, they're my family. They're the ones who came to the graduation party. I didn't have any of my own family, it was them. So the MacArthur fell helped because the money helped me as a single mom. But it helped at my kid's school because I really believe in the public school system. My kids went to the public high school. But for a while, I had them in a Montessori school. And in the school, I mean, it was, you have to pay for them to go there. And I was really short on money and time, but they kept expecting parents to like, do so much at the school. And I'd be like, look, I pay my bill in full.

• 51:27Speaker 00

  I'm struggling to just keep my whatever together. Could you please not bother me? But as soon as I got MacArthur, they stopped bothering me.

• 51:35Mario Gabriele?

  Ooh, that's a great perk.

• 51:36Speaker 00

  Well, I think, I think they real, yeah, that was a great perk. Because I think they understood the situation here, like.

• 51:40Mario Gabriele?

  Yes.

• 51:41Speaker 00

  I'm not your average person. I have a lot going on. Just leave this poor person alone.

• 51:45Mario Gabriele?

  How often do you use the fact that you are officially a genius to win an argument?

• 51:50Speaker 00

  Well, I don't use it very often, but in this really tight, tight, tight job market, we started telling you about. I mean, the reason I know a lot about that is because I have a son who just graduated from college and I went to his, he's in biochemistry. So I'm not talking about astro.

• 52:03Mario Gabriele?

  Yes.

• 52:04Speaker 00

  You know, astro, astrophysics, arguably like a luxury science. I'm talking more of more practical things, the young people who are going to go and figure out the hard problems for us. And many of them didn't have jobs like by the time, you know, I went there a few weeks ago to their senior thesis presentations. But anyway, one of the people trying to give my son advice, an older person, he's like, just tell them your mom's a MacArthur genius.

• 52:28Mario Gabriele?

  That is a good perk.

• 52:29Speaker 00

  Nepo baby, nepo baby for science, you know, just like, you got to use everything you have right now because it's just the networking that gets you in the door.

• 52:36Mario Gabriele?

  Yeah, that makes sense.

• 52:37Speaker 00

  I don't usually use it, but maybe now's the time, right? To cough it up and like, start mentioning it.

• 52:42Mario Gabriele?

  These are, these are great side perks of the MacArthur rant that I never considered. You, you also say in the book, something that I thought was really interesting, which is that how many great scientific achievements are the products of hunches of like intuition? And how some of yours have, have also, you know, come from that. One, just for my own edification, I was curious, like, which ones come to mind as sort of great historical examples of hunches proven correct? And then, secondly, I was curious what current hunches you sort of have.

• 53:13Speaker 00

  The whole thing about these so-called sub-Neptunes is that I had a student and I work on that before they were ever discovered at all.

• 53:22Mario Gabriele?

  So you theorized they would exist?

• 53:24Speaker 00

  Yes, but it wasn't so much theorizing they would exist as the fact that, how would you characterize what they're made of? Because these planets fall in a very awkward range. I'll just take a moment to do a thought experiment with you. Imagine now I'm bringing you something and I give you a box and I tell you it is made of three separate planetary materials, or the option is one of three, or two of three, or three of three planetary materials, rock and iron, or water, or hydrogen gas. So if I give you the box and it's so heavy, it immediately falls to the floor. I think you can guess what's in it.

• 54:01Mario Gabriele?

  Yes.

• 54:02Speaker 00

  Rock and iron.

• 54:03Mario Gabriele?

  Rock and iron.

• 54:04Speaker 00

  It's very, very heavy. Right. And if I give you the box and you accidentally let go and it floats away, then you can guess what it's made of. It's got to be made of hydrogen. That's like a helium balloon. It's so light. But if I give you a box and it's just so average, like, you won't know what's in it. It could be a mixture of iron and, and hydrogen. It could be some water and some hydrogen, or it could be some of all three, you won't know. So what we had done was we were really setting out to think ahead about how would we capture the range of possibilities if these things existed. And then as soon as one was discovered, we could like momentarily write up our paper and put it out there and explain now that it was a bit of a quagmire.

• 54:46Speaker 00

  Because they're very average density, very bland, we can't really tell what they are. So I think that was probably one of my best hunches from the past. So one of the things when I started working on exoplanets, people will ask me, oh, did you always know it would be big? How come you stuck with it? It's like, no, I didn't know. There's no way as like a young grad student, I could have had that foresight. There's just no possibility. I just thought it was cool, it was risky, it was out there, I had nothing to lose. I was not, believe it or not, committed to a career in science, so I could take a risk. But over time, I purposely looked back and unpacked my wins. You know how we're always told to learn from your failures? That's important, but we also need to learn from our successes. And as I've done that, I've really honed my intuition.

• 55:31Speaker 00

  I can kind of now, it's a very below the surface kind of thing, right? But you know, my intuition is so strong, it's like buzzing, buzzing, buzzing for all my work in the lab right now. And I'm in a really special place because I know enough about chemistry, but not too much. You know, when you know too much, you're just going to damp it down. It's not possible, but when you don't know enough, you can naively discover things. And so I just have a big, big feeling about life and non-water solvents. And I'm growing my team and I'm heavily investing in this laboratory chemistry. I call it from the lab to cosmos, rethinking habitability beyond Earth.

• 56:10Mario Gabriele?

  Wow. It's again, you know, I can't help but finding another parallel to entrepreneurship, which is just that, you know, almost all of the great companies of the past 20 plus years have come from people who don't know too much about a given subject. They know maybe enough or, you know, they're sort of self-taught often on the field that they

• 56:30Speaker 00

  Self-taught.

• 56:31Mario Gabriele?

  Yeah, work on and you know, that doesn't always work in science, obviously, but yeah, the openness to question what are is sort of the perceived wisdom seems to be a core part of how you think through these things.

• 56:43Speaker 00

  Yes, and I do want to reflect back on my childhood a bit, although we finished talking about that. I mean, there are two things. One is I definitely had the evil stepfather, very evil. And while I wouldn't wish that on anyone, it gave me a distinct advantage because I learned at a young age not to trust authority. It's a sad place for a kid to be, I'm telling you, because usually you trust your parents, they keep you safe. But when you don't have that, you know, when you're older, you're like, well, why should I listen to him? If he doesn't believe me or believe the work, who cares? I mean, I don't believe older people because they obviously are bad people out there. So that's one thing. But at the same time, I had my dad, who adored me and I lived with him on weekends. And we talked about my dad, he was very, very eccentric.

• 57:25Speaker 00

  He loved me so much, he believed in reincarnation and that we would come back to this earth together over and over again. You know, we were father, daughter, maybe we'd be brothers or husband and wife or business partners. It didn't really matter. And so there I was like at 11 years old, pre-internet, pre-internet. I remember going to the library and checking out like a stack of books, reading about reincarnation and being like, hmm, no, no, it's just not. I just, not for me, I just can't believe that I see no evidence. But that in my childhood enabled me to be open to ideas because the man, my dad, that I trusted and loved. You know, I would definitely entertain what he said, even though I wouldn't take it seriously.

• 58:04Speaker 00

  So I grew up being able to challenge authority and having an open mind to crazy ideas and having the tools to sort through crazy ideas. And I feel like that was a huge, huge win from what was otherwise a traumatic childhood.

• 58:17Mario Gabriele?

  Yeah, you were able to take some, some benefits from a difficult situation.

• 58:23Speaker 00

  But I think those things could be learned. I hope so, like, I hope all those things can be learned. And I do see it in some of my students, like I did have this amazing student one time from China and he would never challenge me. Like, the respect and authority was just a thing you just do not challenge. And I just had to sit him down one day and go, look, you're allowed to respectfully go against me. I mean, to my face, like, you're allowed to push back. That's how science is done and we're going to have to find a way here. I didn't say it exactly like that, but it did evolve for sure. And he's definitely still very respectful, but he had to learn that as an adult.

• 58:58Mario Gabriele?

  And he was able to do it in some respect.

• 59:01Speaker 00

  Yes, I think maybe perhaps some people can't, but some people can.

• 59:05Mario Gabriele?

  I'm curious to what extent sort of some of the revelations in artificial intelligence over the past few years have changed what you do. Has it impacted the sort of signals you're able to get or even sort of more basic things like, I don't know, day to day lab operations or the paperwork and administrative burdens that are associated with that or not really?

• 59:27Speaker 00

  Not really yet. I'm proud to say that when I ask for help from AI for my research, I mean, it's such a great thing. My research is so frontier, it can't help in many ways because it just doesn't know enough and I can tell it's wrong. It does help with administrative things. If I need to summarize something or like I have these undergrads coming this summer and really excited about and they're like our first generation of undergrads who have AI at their disposal, right? So it's really cool because assign them a task, they get it done. It's a table of past Venus missions. For example, that can get filled out pretty quick by AI. That's wonderful. And then we have the question, well, how do you, how do you absorb and maintain knowledge if it's just done in a flash? Because usually the process of gathering the knowledge is gets to sink in and you can absorb it. So

• 1:00:11Speaker 00

  we have other questions going on, but it can simplify administrative tasks, can summarize papers. It can help with making a succinct review. It can't do it for you, but it can help polish the language, you know, take steps forward. I'm still waiting to find AI useful in my own personal research. You know, in exoplanets, I've seen it used to speed tasks up, but rarely for AI to do something we humans couldn't do brute force. We have a lot of ideas and we're, we're working on those.

• 1:00:38Mario Gabriele?

  One of the things that you've talked about previously is that you don't think it's really very realistic for humans to colonize exoplanets because, you know, space is not particularly favorable to biological life that, but that potentially AI intelligence might be able to. Could you talk a little bit about why that's the case in a bit more detail?

• 1:01:00Speaker 00

  Well, there's many threads to that, but one thread people have is unfortunately, perhaps one day AI might take over. And AI might be able to self replicate by 3D printing. Perhaps we humans will meld with AI somehow. We're attached to our phones pretty seriously right now, even being the first generation to get to have smartphones. We have Neuralink or other ideas. I've seen people get trained to move artificial limbs by AI and thinking. Online, you know, I've seen that. So perhaps it's just a matter of time. It could be 100, 1,000, 10,000 years that we're no longer here in the human form and that we're somehow melded to AI and physical hardware, software items in outer space.

• 1:01:45Speaker 00

  That's one idea, not my idea, but in general, it's a general consensus idea.

• 1:01:51Mario Gabriele?

  You have this saying in your book, which is that every problem is ultimately a problem of statistics. Why is that the case?

• 1:01:58Speaker 00

  I think in the book that is supposed to capture how in astronomy, there's just so much out there. You know, on a day to day basis, we're all bogged down by our individual selves, our individual environments, our family, you know, going in rungs outward. But ultimately, there's just so much more out there. There are billions of stars in our galaxy alone. And we have evidence for hundreds of billions of galaxies out there. So if you just think about that for a moment, it's absolutely overwhelming. All the numbers, all the possibilities.

• 1:02:29Mario Gabriele?

  You've said before that sort of probabilistically, thinking of all of those numbers, that you imagine there's sort of almost not must be life on Earth, but it seems certainly very, or life beyond Earth, but certainly possible. Do you have an intuition or a hunch on what that life might look like? Like, will it be phytoplankton? Will it be necessarily a more simple life form rather than something more complex? Just sort of by the odds? Or is that actually a silly way to think about it?

• 1:02:58Speaker 00

  I mean, I like to imagine life on Venus. I think it would be very, very simple life, maybe even more simple than our simplest life form on Earth. Perhaps going back to whatever primitive life first emerged that is now lost to time. But other people will argue that evolution wants to get more complicated and that ultimately. Every life form, planet permitting, will evolve to some sort of complex life. So I'm not sure really what's out there.

• 1:03:24Mario Gabriele?

  You know, I'm curious, to the extent that you're able to identify it, how you end up getting most of your, you know, best ideas? Do you crib from science fiction ever? Do you sort of find that, you know, when you're on a long walk in nature, for example, that you spot something or have these moments of insight? Or is it, you know, more gradual than that?

• 1:03:47Speaker 00

  Well, it's definitely more gradual because it's a lot of accumulated knowledge and it's a lot of processing in the background. When the idea does surface, it's often barely perceptible.

• 1:03:59Speaker 00

  Sometimes it's just like a feeling and then I grab onto it and take it.

• 1:04:03Mario Gabriele?

  Well, I always like to wrap up these conversations with a few sort of more abstract questions. So, uh, yeah, with that in mind, if you had the power to assign a book to everyone on earth to read and understand, which book would you choose?

• 1:04:19Speaker 00

  The book I would choose is called The Giver. This book actually ends up being middle school required reading in parts of America. And that's how I came across it when my kids were in middle school. And it's absolutely astonishing. You're just reading through this book and it's supposed to be a utopia. But partway through the book, there's a little crack in the facade. And I feel like we're all living in a bubble. And once in a while, there's a crack and it's our job to search through what that crack means for us and others around us.

• 1:04:50Mario Gabriele?

  What have been the cracks that have appeared to you over the past few years? That sort of feel like that giver moment, maybe?

• 1:04:56Speaker 00

  Well, that's a little tough to get into.

• 1:04:59Mario Gabriele?

  Fair enough.

• 1:05:00Speaker 00

  Well, one of the big cracks we're facing as a nation is DEI, which intended to bring equity. But a large majority of it was virtue signaling. It has gotten us into a really tough situation right now.

• 1:05:12Mario Gabriele?

  Do you think about what the best? Way to handle that is?

• 1:05:15Speaker 00

  I do. I do think we need to empower ourselves from within. And one of my businesses I've started recently is about confidence. And it's about how to teach people, everyone, but especially women, how to build confidence and overcome the imposter syndrome. Because I think we need to grab some of this and take our own initiative and build our own skills, rather than relying on people around us to solve bigger problems that are perhaps too hard to solve.

• 1:05:42Mario Gabriele?

  You know, you talk about this a lot in the book, but you know, you certainly had to overcome a great deal of skepticism and resistance as a woman in your field.

• 1:05:52Speaker 00

  Well, it wasn't just a woman. I just was very, I had very low confidence. Not sure where it came from. Every young woman has it, it turns out. A lot of others have it as well. And as I was able to overcome it, I've decided to give back and try to share all that with people.

• 1:06:10Mario Gabriele?

  Amazing. Maybe a final question. What's an experiment that you would like to run if you had unlimited resources and no operational constraints? And perhaps you're already working on a few of them.

• 1:06:23Speaker 00

  Well, aside from Starshade,

• 1:06:24Mario Gabriele?

  Yes.

• 1:06:25Speaker 00

  it would be a sample return mission to Venus. So send a cruise vehicle to Venus with a ginormous balloon itself with a small rocket attached. Collect the clouds, package it all back up, launch the rocket to connect with the orbiter and bring it all back to Earth.

• 1:06:42Mario Gabriele?

  Amazing. This was so interesting, Sarah. And yeah, I can't thank you enough for your time.

• 1:06:48Speaker 00

  Thank you.

• 1:06:49Mario Gabriele?

  That's it. Thank you for listening to this episode of the Generalist Podcast. Please subscribe on Apple Podcasts, Spotify, or your preferred podcast app. Ratings and reviews help others discover these discussions. So if you enjoyed the conversation, I'd be grateful if you could take a moment to leave one. For all past episodes and more, visit us at thegeneralist.substack.com. See you next time as we continue to explore the future.