Revisiting the Drake Equation with David Grinspoon

0:00Chuck. Yeah. Dr. Funky spoon. Back in the house. One of our favorites always. David Grinspoon. And in this episode, we found out exactly where we found life. We found it. Did we? I mean. Did we record the same episode together? Yeah. I mean, we didn't find it out in the universe. It's here, but we still found it. Join us again with one of the world's leading astrobiologists on StarTalk. Welcome to StarTalk, your place in the universe where science and pop culture collide. StarTalk begins right now. This is StarTalk. Neil deGrasse Tyson here, your personal astrophysicist. Chuck Nice with me too.

0:51Chuck, how you doing, man? What's happening, Neil? All right. You're a comedian, also acting? Yes. I'm stealing money. That's all. I'm just stealing money, Neil. I don't even know. They don't even know. You make people laugh and they just hand you their money. They're just giving me money and I'm like, you don't even know. I'm just acting like a comedian. But I'll take that, Chuck. So today, Chuck, we got Cosmic Queries. That's a fan favorite, Cosmic Queries. Yeah. And oh my gosh, one of our favorite guests. yes to help us out here excited to have him back we got dr funky spoon dr funky spoon david's grinspoon long-time friend and colleague we kind of came up together through graduate school but we were sort of different sides of the fence i was sort of galaxies and cosmology he was like planets and asteroids and stuff oh man that's like the jets and the sharks right there

1:57just to put that in context right we had telescopes that would reach out to the galaxies we had telescopes that would see the planets but then they started going to the planets is it still astronomy if you can go there you see this was this was part of the divide you go there and bring back samples and stuff you're just a you're a lab technician well you had to observe first you know you had to look through something and see it first david grinspoon welcome back to star talk dude oh thanks a lot it's really great to see you guys uh it's it's a pleasure as always and yeah that divide between uh planetary and astrophysics it's kind of funny i mean it is interesting how it how it evolved historically and at times it was kind of intense like you know And when I was in grad school in planetary science, the astronomy department across the street, the professors were like, oh, don't go over there.

2:55But now that was before exoplanets. Now we need each other more than we ever knew. Yeah. There's been a meeting of the melding of the minds and hearts and souls. Also, our preeminent journal, the Astrophysical Journal, the ordering. I don't know if it's still is this why I haven't paid attention. The ordering of the articles in every released issue was in descending order of distance from Earth. So it started out cosmic microwave background, large scale structure of the universe, galactic. And you keep doing. And way at the bottom is observations of Saturn. it was like clearly the priority prioritization of the universe is is writ large in those pages that's all so david i noticed you have a title that you didn't have last time at first you're an astrobiologist we get that but you're also senior scientist for astrobiology strategy at nasa what is that yeah so that's that's my new job since the last time i really had a a good conversation with you guys.

4:08I started a new role. I, uh, you know, I've always worked with NASA and, um, been supported by NASA for my research and the missions that I've involved in my whole career. But just about a year ago, uh, this week, I started a new job at NASA. I am now a G man. I worked for the government and look at that. Yeah. Yeah, see? You'll never take me alive, Papa. That's right. I am now working at Your Nation's Space Agency, helping to run the astrobiology program. And it's just like it says, I'm doing astrobiology strategy. So really trying to understand and figure out how we can expand astrobiology in new ways and plot the future.

4:58It's a really interesting role for me. It's fascinating. It's very different. I mean, I feel like my career up to this point was preparing me for this in a lot of ways, but it's fundamentally very different from any other job I've had. And it's been a year, but I feel like I'm still learning the ropes. But you don't have power over missions, do you? We do that in our decadal surveys. So do you help shape it after the priorities are set? yeah so i don't yeah absolutely like you say the decadal surveys which are you know the big community input uh exercises to set the priorities for the you know on a decadal time scale just for so the public understands it's why you never see astro folk publicly arguing about how money should be spent we do that among ourselves like in private well yeah like like any good marriage you know what i mean so that so that that sets like the major priorities which we take as our foundational document you know those are in a way our marching orders but within that there's a lot of decisions to be made about how we prioritize different research uh areas and um directions and uh you know what we put what we emphasize and how we communicate about what we're doing.

6:15The decadal kind of defines the shape that we're acting within. But then within that, there's a lot of decisions to be made. And again, it's all about working with the community. We represent the astrobiology community. And so it's not like, oh, what ideas do I have today about what NASA should do? I'm just going to go do it. Of course, I hopefully am interjecting my own creativity and my own ideas, but it only works if we're really working a lot with that community and kind of moving. If you're straight too far, somebody will come down to D.C. and kick your ass. Well, exactly. Exactly. You know, I'm a public servant.

6:54But, you know, it's interesting. It's a different kind of creativity. Before this, I was doing my own research. Now I'm putting a lot of time into facilitating other people's research and figuring out how to creatively get groups of people working together in new ways and helping, you know, create connections between people that that think they're doing separate things, but trying to get them to see how working together, the whole can be greater than the sum of the parts. So it's a real new kind of, I feel like I'm tapping into a new sort of creativity for me. And that's fun. So we kind of need that and even expect it.

7:31But are you following some mission statement that's been established for your strategic plan? Yeah. So as you mentioned, there's the decadal survey, which is, you know, and there's a Planetary Science and Astrobiology Decadal Survey, which is different from the Astrophysics Decadal Survey, although they, you know, they play well together. And then beyond that, there's actually something called the Astrobiology Strategy, which is a 10-year document, which is much more detail about the research priorities and so forth. And part of what I'm doing now, a big part is we're working on a new astrobiology strategy.

8:06So we're actually starting to canvas the community of astrobiology researchers and say, hey, what should our priorities be for the next decade? I solve that right now. Find life. That's, you know, that's that's the big goal. But then, you know, but give us some detail. How do you want us to do that? We're trying to fill in the fill in the steps there. here's the funny thing that you guys are always looking for life have you ever thought about creating it like maybe we're the progenitors like you know when you look at like prometheus it's all about like ah you know these aliens came they left you know some microorganisms in our water and that made us oh you mean prometheus the movie the movie not actual people to aliens just to to catch people up with your your sci-fi fluency that's my sci-fi yes so so is it ever us maybe we are the aliens that create and see the life elsewhere it's funny you should ask because there are people working on um well obviously there's there are people working on sort of origin of life experiments not necessarily that they're literally trying to create uh organisms organisms but they're trying to recreate the chemical steps to help us understand how life started and that's you know that's astrobiology supports a lot of that kind of uh experimentation there are people actually trying to work on synthetic life like could we create some kind of a life form and that you know it's a really interesting idea we that's certainly something how that's a avenue towards learning a lot about life if we could do that just to be clear when someone says this is made of synthetic leather it means it's not leather it just kind of looks and smells like leather if you're gonna say synthetic life you're not making it out of some ingredients that life is not made of you're actually making life right so so that that word synthetic it can be can mean a few different things but there are i think it's the wrong thing in person in terms of a person's first yeah hearing yeah maybe you want to say artificial or you know, laboratory created.

10:19And that's not a major effort of astrobiology now, but it's certainly something that some people are thinking about. And it is very related to this question of, you know, alien life. And some people have predicted, you know, sort of provocatively, but maybe they're right, that the first alien life that we will discover or come to know will be something made in a laboratory, you know, and then you can say, well is that really alien it comes from earth but it's pretty alien in a way yes the the impossible meat alien yeah exactly what do they call the turkey made out of out of tofurkey yes tofurkey You made a new turkey out of Tofurky.

11:22I'm Kais from Bangladesh, and I support StarTalk on Patreon. This is StarTalk with Neil DeGrasse Tyson.

11:37David, we had a guest recently who was a roboticist describing a collaboration with NASA about the search for life in the subsurface of Enceladus. We know Enceladus has these striking plumes that we can see sort of in those side views when it's properly lit by the sun. You see these sort of geysers coming out. So he's working with folks at NASA to make a worm, a robotic worm that'll go down that hole and then look around for life because it's frozen on the top. And then you have sort of liquid water, we presume, below. So do you know about that? And do they need your permission or do they need your blessing?

12:25Or do they need a fishing license? He's like Sam Drucker, right? He's got the fishing license. No, I mean, yeah, we put we certainly put some resources into these experimental and speculative engineering projects that could someday lead to a new way, a new kind of mission to search for life in a place like Enceladus. Not just a lander and, you know, the usual. Right. That's not a current mission that's in our plan. Like, we're definitely going to do this. But part of our strategy is to support people with innovative concepts that could lead to future missions. And certainly Enceladus is one of the places that's very high on our list of places that we would like to visit and characterize for habitability and perhaps search for life.

13:17for the reasons that you mentioned, Neil, it seems like a place, not only is there liquid water in the interior, but the hints we have about that ocean based on what we've seen in that plume suggests that the chemistry of that interior ocean may be really conducive to life. It may have the right mix of chemicals to have sources of energy and the biogenic elements, you know, the right elements to make life. So we have some hints that not only is there an ocean on Enceladus, but it might have the good stuff. So it's definitely high on our list of places that we intend to explore. You know what I never asked you guys, and this is for both of you, a very icy crust frozen over, right?

13:58And then underneath a liquid ocean. So what is making it so warm underneath that we can have a liquid ocean, but clearly it's like not in some Goldilocks zone because the outside is a frozen crust. Yeah, well, you know, it's been a big surprise of planetary exploration that so many of these moons of the outer solar system have these warm active interiors. We didn't expect that. Maybe we should have if we were smarter, you know, because the physics works out. But we thought they would, before we sent spacecraft to Jupiter and Saturn, we thought they'd just be these greater dead ice balls. But it turns out that being near these giant planets, the way the moons interact with each other, flexes their interiors basically by tides.

14:46The interiors are getting squished. And that makes certainly a place like Europa keeps the interior warm and keeps pumping heat from basically the gravitational influence of those giant planets. There's also any place where the rocky core, and all these moons have rocky cores, have some sources of just natural heat from radioactivity in the rock so it's some combination of natural radioactivity and the tidal history of these moons that have like warmed their interiors so so i remember enceladus i'm not entirely moon fluent but enceladus if memory serves orbits saturn correct that is correct okay last last i checked yeah it was like uh i'm just giving you that one neil i don't have to Sorry, I thought you were just pausing for dramatic effect.

15:40When Neil deGrasse Tyson says Enceladus orbits Saturn, correct? I'm going to think that that's rhetorical and just shut up. I was going with that. Jupiter has no shortage of moons. It's got tidally heated moons. It's got moons with ice on it. Everybody's favorite, Europa. And Jupiter is only half the distance out there compared with Saturn. So why would Saturn moons have any priority at all? relative to Jupiter's moons. Cassini at Saturn, which was the orbiter that really brought those moons to us, turned up some really surprising things. And probably the biggest surprise was that Enceladus is so weird.

16:21And it's weird in enticing ways that it seems... Some people think it's the best candidate for finding extant life. Some people think it's even a better candidate than Europa. Now, I don't want to get into that fight, but we're going to Europa with the clipper mission and which is great because europa is a very promising place to look but what's amazing about enceladus is as you mentioned it has these geysers so it's literally you know like uh shooting its guts out into into space and there is stuff from that ocean landing on the surface some people think we can go to enceladus and just scoop up snow from the surface and look for organisms in the snow and never have to go down into the liquid right it's it's the ocean is so accessible because it's literally squirting out into space.

17:06So what's this? I heard, you know, some of the chemistry, like hydrogen cyanide, is that right? Is it HCN or something? Yeah. Yeah. Which sounds like, oh, that's poison. But actually it's a very, and you're thinking about the origin of life and what primitive life may need. It's a very juicy chemical because whenever you've got nitrogen bound up in a carbon molecule, that's, you know, the basis of so much. That's the basis of amino acids and all this stuff so so hydrogen cyanide is actually a very promising sign if you're looking for a life somewhere but just to be clear it will kill you if you ingest it you're talking about the formation of life just just to be clear yes yes no don't don't try this at home but i know it giveth and it taketh away there you go chuck so it's hydrogen cyanide i think that's the gas and gas chambers or some variant on that uh but you're saying if hydrous hcn the c in the end together is what really that's what's fertile for organic chemistry that's that's enticing that's because we you know one thing we've learned is that there's carbon molecules everywhere in the i mean many places in the universe which is encouraging for astrobiology that it's not hard to you know the universe likes to make carbon molecules which is great but you You need certain things beyond that.

18:26And carbon bonded with nitrogen is very key to all the biochemistry we know. So when you see that in a natural environment, you go, hey, that's encouraging. All right. So this is what's attracting people. All right. Interesting. This is a Cosmic Queries episode. That's right. And Chuck has collected them. So, David, you may remember in our Cosmic Queries, we tell people you're going to be on. They're reminded of your expertise. and they come in with their questions that are inspired by the curiosity that your work drives. So let's see what you got, Chuck. Okay, we got it. Let's start off with Brad Lester.

19:07Brad Lester says, hello, Dr. Tyson, Dr. Grinspoon, and Mr. Nice. Didn't get the memo on the Lord part, did you there, Brad? Okay. Wait,

19:18Chuck, these are paying customers? Oh, that's right, that's right. Nice to them. By the way, thank you all for supporting us on Patreon. We certainly appreciate you. And we appreciate you just even more than we appreciate your money. Just letting you know that. And just to be clear, if they call you Mr. Nice, they must be new members because they don't know the history. That's true. That's true. So be nice to the new folks. I will be nice. That's right, because he's new too. So we got a super nice. So I've heard scientists speak about how unlikely it is for intelligent life to evolve into a humanoid form on other planets.

19:53That being said, has any study been devoted to the likelihood of other exoplanets that might contain trees or other plants or structures comparable to trees? If tree-like flora existing elsewhere in the universe is reasonably likely, and if we assume sentient life could also evolve on these planets, It is is it reasonable to conclude that some organisms would evolve to have limbs, hands, fingers or similar appendages to allow them to spread to the tree heavy environment? Maybe I'm mistaken, but isn't that the reason why primates evolved in the first place? And thus, like humans, contain two arms and two legs and fingers in which to grab things.

20:33So, you know, damn. See, that's not where I thought he was going with that. I thought he was. I thought, can we have sentient trees? like they have in Lord of the Rings? That's such a good question. You should get this guy to be your next guest on this show. No, I mean, it's like what he's asking about is something that we call convergent evolution. Like, you know, on the one hand, we know evolution is full of accident and contingency. And, you know, like Stephen Jay Gould used to say, if you ran the tape again, you wouldn't get the same biosphere because there's so much randomness. Why would you expect anything to be the same since evolution is so random?

21:10But the opposite of that is that there are certain things you can see on Earth that evolve similarly in different environments multiple times because they make sense. They solve a problem. And evolution is all about solving problems. Right. And so we do expect on other planets, probably photosynthesis evolves, like the ability to use sunlight, because what is there all over the universe? There are stars in any environment with, you know, that's a great source of energy. So if you have photosynthesis, you're going to have some organism that spreads out and has something like leaves so it can capture that.

21:47And then you're going to have something like branches because that's sort of a natural, you know, so you can make these arguments. Yeah, there'll be things that are like trees. And similarly, you can say, well, there's not going to be a humanoid because that would be unlikely. Why would you expect aliens to look just like us? But then you go through some of our characteristics. Like a head makes sense to have one central processing system for the brain and two eyes make sense to have, you know, stereo vision. And yeah, like your questioner astutely says, something to grasp and swing from tree branches.

22:20So, you know, I would not expect humanoids like we're going to mistake them and say, oh, wow, that, you know, are they from Earth? I think nothing's going to be that similar. But some characteristics in common, there's a rationale for that. And one of the fascinating things, if we ever get to meet complex aliens, that's how we'll answer this question. You know, not by speculating, but by finding out what they're like. And by the way, you don't have to actually, I mean, you don't have to necessarily evolve hands and instead of limbs, you could just evolve tentacles. Right, right, right. But David, when I think of convergence, I wouldn't be so specific as you've been.

23:08I would just say there's convergent evolution that enable organisms to sense things at a distance. For us, it's sight. And there's other versions of sight, right? So insects can see, but they don't have a retina eyeball situation. But they can see for sure, right? And then locomotion, you don't have to talk about legs or arms, but can you move? Trees can't move. Okay. Not at least, I mean, the ones in the Wizard of Oz, I think, chase Dorothy down the street. But I think there were some. And they threw their apples. Threw their apples at her. So you have locomotion. And in that need and that valuation of that talent, you have snakes with no arms and no legs at all, yet they move along just fine.

24:03So when I think just come to it from the world of physics, I'm not I don't have the urge to be so specific about what it is so much as what it accomplishes. Yeah, no, absolutely. I mean, it's a fascinating question. You're right. It's all about the needs being met because that's what evolution does. And there are some cases on Earth, though, of very specific things like eyes evolve more than once. Yes. And you can say that's all on the same planet with the same conditions. So who knows? I mean, I think we can speculate, but this is what I love about astrobiology and exploration is that that's how we'll find the answers is by going out there and seeing.

24:42Give me some more. This is Tom Lindelius from Sweden. He says, greetings from Sweden. Or did he say greetings from Sweden? Okay. yes chuck thank you for interpreting and right after that he says are easty being or bischie being or easty being or bischie board uh is that what he said right after that no anyway he says we already know that neil's favorite alien movie is the blob but what is your favorite alien movie, Dr. Funky Spoon. And what do you think the first encounter, actually bigger than microbes, might look like when we encounter aliens? Let me just clarify. That's my favorite. It's not my favorite alien movie.

25:32It's my favorite alien. Right. Just to be clear, because it has no bones, no skin, no mouth, eyes, teeth, hair, fingers. I think it's the most creative alien ever put on the screen because it looks nothing like any other life form on earth and if you're going to come visit from another planet and you look more like humans than either humans or you look like anything else on earth you're not being creative in hollywood right so yeah so i want to know too david what's your favorite so so i mean i have to give you two answers if that's okay because in terms of favorite i'm old school with a favorite movie to me it all goes back to 2001 and one and and part of that is because as neil says you know you if you show the aliens they're going to look cheesy no matter what and in 2001 they did the brilliant thing of implying them without really showing them uh in this pretty mind-blowing way by the way i'm told and you might have some other insight here that carl sagan at the time though young advised the producers of that film to not show the aliens and leave it to your imagination and that fact was preserved in his novel contact when the screen version at least you don't see the aliens at all yeah no that's a new way to think about it that's absolutely right hey i think you know uh rumor has it or the story is that that sagan and kubrick didn't really get along that well and carl didn't have that much input into that film but his one substantive piece of advice that was followed was don't show the aliens because in some earlier drafts they were going to try to But it's always a brilliant storytelling ploy is to leave things to the imagination.

27:11When you think about Jaws, you don't see the shark until how long into the movie. Right. And again, you're right. You're right, Neil. That was what they did in Contact, to brilliant effect. The one depiction that's coming to mind of an alien organism in a movie that I think is pretty good is in Arrival. You know, where they have those. The septipoids. Oh, the septipoids. Is that true? Thank you. I just saw it a few days ago. Oh, awesome. Awesome. I like that. An odd number is good, too. But, you know, and they're kind of floating there and behind this frosted glass in their own atmosphere. And you can sort of see them.

27:50But to me, there's nothing about them that seems like fake or implausible. I'm like, yeah, that looks like an alien. So I give them high points, high marks. Yeah, but you miss the ray guns and stuff like that, you know. Yeah. well so you said you had two movies so the arrival by the way there's another movie the arrival with charlie sheen in it playing an astrophysicist yes so you're talking about the more recent one where they have the the ash yet the physicist and the linguist to decode amy adams amy adams yes yes yes so that's the more recent one from a few years ago so what's the other film the charlie sheen one by the way is is underrated let me just say that charlie sheen one is pretty cool because it's about climate change oh okay i'll go back and check it out yeah all right go ahead no the other one i already mentioned 2001 i said that's my sort of foundational one where that's you know i like the aliens because you don't see them nice all right this is uh ivan or ivan de souza who says hello doctors and lord greetings from abu dhabi united arab emirates long time fan and recent patreon member well thank you uh My question is about Jupiter's moon Europa.

29:06I can't help but wonder what life may possibly find in that vast ocean that insulates its icy surface. Yes, I am ruling out impossibility because I really want to be there. What do you think we will find? And in what form? Please do visit this side of the world. Would love to take y 'all around. Okay, there you go. Very cool. I love open standing invitations. If that existed more frequently in the world, imagine how much more at peace we would be because there's an invitation awaiting you, right? Not a wall preventing you. It's just a very, very kind, forward thinking gesture. We're going to put a door in the wall.

29:50There's a door. Yeah, no, I love that. And I love the fact that these kinds of questions make it so obvious that we're all we're all on the same side when we're thinking of what's out there, you know. So that's great. What's your best? What's the best thinking about Europa? Because that's that gets everybody's imagination for sure. Europa was in 2010, the sequel to 2001. And Europa has shown up in several storytelling efforts. there's another one called the Europa Report which is a film lower budget sci-fi film I know about that because I'm in it oh get out! Interesting I have a very short cameo and it was simple because they just clipped something from when I was on CNN and the clip was I can't wait to go ice fishing on Europa cut a hole in the ice, put a camera lens down there and see if anything swims up and licks it I think that was my entire quote.

30:50I love it. Licks the camera. Could you imagine the giant European tongue?

30:58Europa is one of those places that's just been in our imagination for a long time. And actually, so I have a cameo too. In episode six of the original Cosmos with Carl Sagan, Traveler's Tales, they show the scene in um at jpl when voyager 2 showed the first close-ups of europa that had ever been seen by a spacecraft somehow carl convinced the you know them to let a camera crew in the room while this was happening and i'm actually an undergraduate intern in a skinny kid with a giant afro holding a clipboard in the very back of that scene on screen for like three frames

31:48did your mom have a poster of that you know with a circle and an arrow of course of course yeah but so Europa you know and that was 1979 summer of 1979 then that was the first you know Europa came to our attention as like a really weird world but just to be clear Cosmos was released in 1980 so it was filmed that moment took place in 1979 yeah and that you know we saw with Voyager, a moon with no visible craters on the surface. So that tells you it's young. There's not, hasn't been sitting there getting hit. And these weird lines turned out, you know, which turned out to be cracks in a thin ice shell with an ocean of liquid water.

32:27And the more we've learned about that, it seems the ocean probably has probably the right kinds of chemicals to support some kind of metabolism. And, you know, it's more and more encouraging to imagine some life form there and what's really cool is that we're going back there um i have to interrupt you again chuck uh he said a thin coat of ice but let's get him to quantify that by thin i mean maybe by maybe uh between 10 and 100 kilometers oh my little thin little coat of ice okay this is not this is not you know dangerous ice to go ice skating on you would you would not fall through just to be clear i'm just trying to truth in advertising here thin ice out of david's mouth this is a this is a object a world about the size of our moon so if it's just got 10 kilometers of ice over a deep ocean that's it's might be it's probably our solar system's largest ocean of liquid water more water than all on earth so it's it's impressive in that way as far as we know life on Earth began in our oceans.