Cosmic Queries – Alien Worlds and Extremophiles with Kennda Lynch

What will life be like on other planets? On this episode, Neil deGrasse Tyson and comic co-host Chuck Nice explore the origins of life on alien planets and extremophiles right here on Earth with astrobiologist Kennda Lynch. (Originally Aired February 22, 2022)

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

• 0:00Neil deGrasse Tyson?

  Hey Startalkians, Neil here. You're about to listen to an episode specially drawn from our archives to serve your cosmic curiosities. Check it out. Welcome to StarTalk, your place in the universe where science and pop culture collide. StarTalk begins right now. This is StarTalk, Cosmic Queries Edition, and today's subject is extremophiles and alien worlds. One of my favorite subjects. Chuck, what do you think about that topic?

• 0:39Chuck Nice?

  Uh, kinda sounds like aliens gone wild. Call right now. It's aliens gone wild. You've never seen aliens like this before. Extremophiles.

• 0:52Neil deGrasse Tyson?

  I love me the sub, little bit of this subject, and but we have a, one of the world's experts on it.

• 0:58Chuck Nice?

  Yeah.

• 0:59Neil deGrasse Tyson?

  On StarTalk today, Kennda Lynch. Kendra, welcome to StarTalk.

• 1:03Speaker 02

  Thanks for having me. I'm so excited to be here.

• 1:05Neil deGrasse Tyson?

  Excellent, excellent. You, you have a PhD in this stuff, and but let me just alert people that your expertise is, is some kind of amalgam of whole fields that were previously distinct from one another. Cause I think of geology, and I think of biology, and I think of modern astrophysics, and you just took a big fat stapler and crammed them together, and then you, and you do all three of these all at once. How is that even possible?

• 1:34Speaker 02

  Um, it's called astrobiology.

• 1:37Neil deGrasse Tyson?

  No, but you gotta know your geology too, right?

• 1:42Speaker 02

  You have to know, yeah, I mean, so, yeah, it's kind of this interesting thing where you just gotta learn to wear a lot of hats, and, um, and you don't necessarily, you, you should have, I mean, ultimately, you have expertise in one thing a little bit more than the other, but you have to know enough about the others to kind of pull those pieces in because ultimately, they all are really interconnected. And you also have to know when you don't know something and pulling the right people to work with you, but you have to be able to speak their language. So having that understanding of geology, so I can talk to a hard rock geologist about, you know, how I think my bugs are eating their rock, you know, is important, and being able to have the same, you know, same conversation about it is really important.

• 2:19Chuck Nice?

  Let me tell you something, this is why I love being on this show. It's the only time you will ever hear somebody say, and I have to talk to them about how their bugs are eating my rocks.

• 2:29Neil deGrasse Tyson?

  There's a sentence, I did not see that sentence coming.

• 2:32Chuck Nice?

  I did not either.

• 2:33Neil deGrasse Tyson?

  But Kendra, you work on Earth.

• 2:35Speaker 02

  Mm hmm.

• 2:36Neil deGrasse Tyson?

  So why, what does it have anything to do with aliens on other worlds?

• 2:41Speaker 02

  Well, I mean, the reality is, is when we're trying to understand life in the universe right now, we only have one data point, and that's Earth. So, um, you know, we have to kind of work on Earth and try to understand life here. And, and really, when we think about it, it's a big question. How did life even come to be on Earth? How did life, Earth come to be this big cradle where there's lots of life just kind of crawling all over it and in it and everywhere? And.

• 3:05Chuck Nice?

  Let me, let me help you with that, Kendra. Uh, bugs started eating rocks.

• 3:12Neil deGrasse Tyson?

  Chuck, Chuck is not going to shake that sentence for the next five years.

• 3:18Neil deGrasse Tyson?

  Yum, yum, yum, tasty rocks.

• 3:21Speaker 02

  But when we, but when we really try to understand, looking for life in the universe, you know, a, a logical first question, and, and especially since we've tried and, and hadn't been too successful in the past, looking for life on other planets was, well, how do we, how well do we understand life here on Earth? Do we understand the extent of where life can live on Earth? Do we understand how life arose on Earth? And kind of what did early life look like on Earth? And, and, you know, where can we go to look for it? And what kind of environments did it live in? And those are a lot of the questions.

• 3:50Neil deGrasse Tyson?

  Okay, I'm, I'm an old man here. When I learned about this, it was, we need the 72 degree tide pool for, for life to thrive on Earth.

• 3:59Speaker 02

  Yeah, yeah.

• 4:00Neil deGrasse Tyson?

  That's how, that's how old I am. That's how old I am.

• 4:04Speaker 02

  One of the things that we have learned.

• 4:05Chuck Nice?

  Life is not comfortable unless it's room temperature.

• 4:08Speaker 02

  Uh, yeah, no. And it needs just the right amount of sugars and it needs, and it needs this special kind of media. No, what we have learned is.

• 4:15Chuck Nice?

  Every once in a while, every once in a while, life is just like, who touched that thermostat?

• 4:20Neil deGrasse Tyson?

  Exactly.

• 4:21Chuck Nice?

  Now, which one of y'all touched that thermostat?

• 4:23Neil deGrasse Tyson?

  On its barko lounger.

• 4:26Speaker 02

  That would, that would be, that would be us as a life. We, we're the ones that kind of need to, we need, we are the ones that glamp, right? But, but microbial life, man, every time we think we got those bugs figured out, they do something crazy. And we're like, wait, what do you mean you can live on a nuclear reactor? Wait, what do you mean you can live two kilometers down in a, in a subsurface, in the subsurface, and we find you when we're mining for gold? What do you mean you can live?

• 4:49Neil deGrasse Tyson?

  Right, okay, yeah, yeah.

• 4:50Speaker 02

  In like, like, super hot water that's also salty and acidic? What do you mean? So.

• 4:57Neil deGrasse Tyson?

  Okay, wait a minute. Three sentences ago, you used the word glamp. Could you please, for anyone over fifty, could you just tell people what that word means?

• 5:04Speaker 02

  It's like, it's like camping, but glamour camping, like bringing your house with you camping. So you, you maybe have like, you, you're not really camping. You're in the wild, not really. Cause maybe you like tow a big old like house trailer with you and that's your camper.

• 5:17Neil deGrasse Tyson?

  If you can still watch HBO in your trailer, you're not camping.

• 5:20Speaker 02

  Yeah, basically, basically, you know, if you've got, yeah, if you've got a hot tub and, you know. And you've got your, and you've, and you've got your, your, um, your Keurig or your Tassimo or your, what's the other one? You got that making your coffee, you're not camping.

• 5:35Chuck Nice?

  That's why I camp at the Ritz Carlton.

• 5:36Speaker 02

  There you go.

• 5:39Neil deGrasse Tyson?

  Okay, so you're a staff scientist at the, at the storied Lunar and Planetary Science Institute. Um, is that right? Is that, no, just Lunar and Planetary Institute.

• 5:47Speaker 02

  Lunar and Planetary Institute, correct, yes.

• 5:49Neil deGrasse Tyson?

  Right, right. And, um, that's based in Houston, Houston, Texas. And we're especially interested in you today because you, um, you're featured in episode two of Netflix's docu-series, what's it called? Alien Worlds.

• 6:05Speaker 02

  Yes, yes.

• 6:06Neil deGrasse Tyson?

  So, um, uh, pick up the action for us. Where, where, where do we find you?

• 6:10Speaker 02

  Um, you find me, uh, a- a- as far as in the episode, yeah, right when we open up, right in the beginning, you see this alien landscape that kinda looks, to my opinion, it looks like Mars. But we're actually in the, uh, Dalal Hydrothermal System, which is in the Danakel Depression in Ethiopia. And the Danakel Depression.

• 6:27Neil deGrasse Tyson?

  So hydrothermal, this would be heat emerging from Earth's crust. Manifesting, uh, on the surface somehow.

• 6:34Speaker 02

  Yeah, hydrothermal, meaning that it's, um, it's heat coming from the, um, from this, the, the Earth's subsurface. And in this case, a hydrothermal system usually meets heat-generated waters, like geogenerated, um, water manifesting up in the surface. So there's water flowing in the subsurface, passing over usually like, um, what we call a magma pocket. There's a big pocket of lava. And there's water flowing over it, getting superheated and then pushing up to the Earth's surface and boiling out and speeding out all sorts of hot gases and everything like that. And that's called a hydrothermal.

• 7:03Neil deGrasse Tyson?

  So at those, at those high temperatures, does it absorb a lot of minerals from the rocks that it passes through?

• 7:08Speaker 02

  It absorbs a lot of minerals. So there's a lot of, um, what we call, um. And anions and cations, there's a lot of dissolved constituents, um, chemical constituents. And especially in the Dalal system, it also goes through su- a subsurface salt deposit. So not only is it getting minerals from like the, the, the, from just like the, the ground, the subsurface rock, like over the magma pocket, pocket, but it's also picking up all these minerals and dissolving all these salt minerals. And so Dalal, um, is amazing because it is, it's hydrothermal, really hot and super salty, hyper saline. And it's also acidic because there's also all this iron and sulfur that make it super acidic. So.

• 7:46Neil deGrasse Tyson?

  And that's where you wanna find life.

• 7:48Speaker 02

  Yeah, and it's, it's what we call a polyextreme environment. And it's so amazing. And it's a, it's a crazy challenge for life. And yet, um, you know, there's multiple teams of us working there that are finding evidence for life i- i- in these, this environment. And.

• 8:04Neil deGrasse Tyson?

  Okay. So, so the, so the Dead Sea, which is a highly salinic body of water, could only have been named that by people who did not have access to a microscope.

• 8:13Speaker 02

  Yeah. Cause there's a lot of life in the Dead Sea. Salt.

• 8:17Neil deGrasse Tyson?

  I, just no fishes, no vertebrate fishes.

• 8:19Chuck Nice?

  Kinda get the feeling that the Dead Sea was named, cause somebody drank it. And then everybody else was like, you see what happened?

• 8:30Chuck Nice?

  Everybody, don't, you see what just happened?

• 8:35Speaker 02

  There you go.

• 8:37Neil deGrasse Tyson?

  Water, water all around and not a drop to drink.

• 8:40Chuck Nice?

  There you go.

• 8:41Speaker 02

  There you go.

• 8:41Neil deGrasse Tyson?

  Um, so, so tell me about that. I, I read something about, there's an algae pool nearby or in some other parts of your work. What's going on there?

• 8:49Speaker 02

  Uh, in, in Dalal or in, um, other, other sites that I work at. Um.

• 8:55Neil deGrasse Tyson?

  Oh, well, just, I, I, I just, I just have notes that I'm piecing together here. Just pools of algae in a toxic liquid. What's going on there?

• 9:03Speaker 02

  Pools of algae. So we have these bubbling pools, right? And they're literally like, you literally have elemental sulfur precipitating out of these waters. And you can see like.

• 9:12Neil deGrasse Tyson?

  Sulfur. So it stinks.

• 9:13Speaker 02

  Oh, it's, it stinks. And it's like, you think the Dead Sea's deadly? Oh, no. Dalal's deadly. You'll see when we're walking through there, you literally see, if you get too close to the ground, there's so much, um, hydrogen sulfide gas and carbon dioxide gas. And if you get.

• 9:27Neil deGrasse Tyson?

  Ooh, well, you gotta tell Chuck. Tell Chuck what hydrogen sulfide gas smells like.

• 9:31Speaker 02

  Um, rotten, rotting eggs.

• 9:33Chuck Nice?

  All right, listen.

• 9:34Neil deGrasse Tyson?

  No, no, you can, he's a comedian, you can do better than that.

• 9:36Chuck Nice?

  I knew, I knew what it was, and I'm sitting here. I'm sitting here like.

• 9:40Neil deGrasse Tyson?

  Holding him, holding himself in.

• 9:41Chuck Nice?

  I am trying my best. I, you have no idea the amount of restraint I just exercised. I have 15 fart jokes right now that are bubbling up in me.

• 9:53Neil deGrasse Tyson?

  They're backed up.

• 9:54Chuck Nice?

  That's the wrong way to talk about a fart joke. But.

• 9:58Neil deGrasse Tyson?

  Chuck has fart jokes backed up.

• 10:01Chuck Nice?

  Backed up.

• 10:01Neil deGrasse Tyson?

  The whole time you're talking about this, Kendra.

• 10:04Chuck Nice?

  I was ready to explode with fart jokes, this is all I'm saying.

• 10:12Neil deGrasse Tyson?

  Okay, so hydrogen sulfide, H2SO4, is that correct?

• 10:16Speaker 02

  H2S, actually.

• 10:17Neil deGrasse Tyson?

  Oh, just H2S. Oh, H2SO4 is sulfuric acid.

• 10:20Speaker 02

  Yeah, and that's what's in the water, is the H2S. The sulfuric acid is actually, there's H2S, low malarity, so, I mean, well, I don't know, I haven't touched the water, but in, in other acidic environments, usually the H2S is kind of low malarity, because I've also worked in the Rio Tinto Acid River system, and so the H2S is pretty low, like, it's not gonna like immediately burn your skin off, you know, you'll, you'll get a nice peel though from it if you.

• 10:42Neil deGrasse Tyson?

  Okay, so that's the place, if you're gonna eat beans, no one will blame you for anything.

• 10:45Speaker 02

  Yeah, not at all.

• 10:46Neil deGrasse Tyson?

  Because you got, you got to- total, the whole landscape to blame it on.

• 10:50Speaker 02

  Yeah, nobody's gonna even notice.

• 10:51Chuck Nice?

  I would do very well there. I, I would do very well there.

• 10:57Speaker 02

  Yeah, nobody's, nobody's gonna notice that.

• 11:00Neil deGrasse Tyson?

  Chuck, for one night only, an evening of fart jokes.

• 11:06Neil deGrasse Tyson?

  So Kendra, wh- uh, what, what, where did you grow up?

• 11:09Speaker 02

  Um, I grew up in, I'm a Midwestern kid, I grew up in a town called Rockford, Illinois, which is just west of Chicago, about 90, about 90 miles. I went into Chicago a lot, a lot for, you know, going to see shows and.

• 11:21Neil deGrasse Tyson?

  Well, just to be clear, if you were just 90 miles west of New York City, you were across New Jersey into Pennsylvania. So, to, to index your location to be 90 miles in any direction from Chicago, um, does that mean there's no other big city you can tell us what you're near?

• 11:38Speaker 02

  Um.

• 11:40Speaker 02

  No, not, not where I am. Cause I'm, cause I'm west. If I was east, I could say, you know, Detroit's not far away.

• 11:46Neil deGrasse Tyson?

  Detroit.

• 11:47Speaker 02

  You know, if I was east of Chicago, but I'm west. So no, it's kind of, kind of open plains and cornfields and stuff. Uh, north of me though is Green Bay. If I had straight north, you'd be in Green Bay in a few hours.

• 11:58Neil deGrasse Tyson?

  And we've all heard of Green Bay.

• 11:59Speaker 02

  Yeah, but I'm a Bears fan, so you know, let's not go there.

• 12:02Neil deGrasse Tyson?

  Oh, the Bears. So how did you, uh, so, uh, how do you land on extremophiles as a career goal?

• 12:10Speaker 02

  Oh, well, you know, um, uh, this is interesting because I had a different hat on when I started my career. I actually started, um, learning how to try to grow food and keep astronauts alive on other planets. I started out as-

• 12:20Neil deGrasse Tyson?

  That's cool too. Both of these are cool.

• 12:22Speaker 02

  I started out as a systems engineer, um, working on space station and trying to keep people alive. But in my education, I dual, I, I was, I'm nuts and I, um, did a dual degree. I literally have two bachelor's degree, one in engineering, one in biology.

• 12:37Neil deGrasse Tyson?

  Generally, if you're nuts, you don't have to tell that to other people because it's just completely clear.

• 12:41Chuck Nice?

  It is true. Yeah. By the way, all you have to do is say, I got two bachelor's degrees at the same time. And people will look at you and go, you must be nuts.

• 12:53Speaker 02

  And, and, and so part of, yeah, so, yeah, well, yeah. Um, and I like pain apparently. So, you know, there's that. Um, part of it, part of my training was to also learn about microbes. Cause when growing, trying to grow plants and develop earth microcosms, you know, microcosms, you have to understand, you know, not only how humans live, but how everything else that's going to interact lives. So I took classes in, you know, um, aquatic ecology. I took classes in lake ecology. I took classes in plant biology, you know, and I took classes in microbiology. And so-

• 13:24Neil deGrasse Tyson?

  Wait, wait. So, so at the end of the day, you realized you took two different majors worth of courses? Is that what happened there?

• 13:30Speaker 02

  Yep.

• 13:31Neil deGrasse Tyson?

  So what are the two majors? What were the two?

• 13:32Speaker 02

  The first one was basically systems engineering. So it was all of, I took a full course of engineering classes. And then I took a full course of general biology classes. And, um, my engineering degree lets me specialize. So I was able to use a couple of my upper level biology classes for my specialization in engineering. So.

• 13:49Neil deGrasse Tyson?

  Wait, wait. So your PhD, what was the title of your PhD thesis?

• 13:53Speaker 02

  A geobiological investigation of the hypersaline sediments of Pilot Valley, Utah. A terrestrial analog to ancient lake basins on Mars.

• 14:01Chuck Nice?

  Wow.

• 14:02Neil deGrasse Tyson?

  Wow, okay.

• 14:03Speaker 02

  That's why I had to read it, I couldn't remember.

• 14:05Chuck Nice?

  I gotta tell you right now, I'm sorry he asked.

• 14:11Neil deGrasse Tyson?

  I retract the question.

• 14:15Speaker 02

  The funny thing is, my PhD was still an engineering degree. I unintentionally got three engineering degrees along the way.

• 14:21Neil deGrasse Tyson?

  I'm liking it. Oh, the masters along the way?

• 14:23Speaker 02

  Yeah, aerospace engineering for my masters.

• 14:25Neil deGrasse Tyson?

  Okay, so you were totally loaded.

• 14:27Chuck Nice?

  What do you think about, since you're a microbiologist and you were talking about growing food as one of your tasks when you were working on space stations? What do you think about Matt Damon growing poop potatoes on Mars?

• 14:38Neil deGrasse Tyson?

  Poop potatoes on Mars? We need the final word there.

• 14:43Speaker 02

  He would have had some problems with his thyroid because of all the perchlorate in the regolith, so yeah.

• 14:51Chuck Nice?

  Wow.

• 14:51Speaker 02

  There are some issues.

• 14:52Neil deGrasse Tyson?

  Okay, just to be clear, I gotta unpack that. Wait a minute, wait a minute. So, on Earth we have soil.

• 14:59Chuck Nice?

  Right.

• 15:00Neil deGrasse Tyson?

  Which is rich in microbes that participate in the ecosystem.

• 15:04Speaker 02

  Yep.

• 15:05Neil deGrasse Tyson?

  On the moon and on Mars, there is no soil.

• 15:09Speaker 02

  Yep, no there's none.

• 15:09Neil deGrasse Tyson?

  Whatever, the dust is there is like

• 15:11Chuck Nice?

  Powder.

• 15:12Neil deGrasse Tyson?

  ground up rock, basically. And so, and you call it regolith.

• 15:17Speaker 02

  We call it regolith because it has not been processed by microbes that we know of. On the, like, there's definitely not on the moon and on Mars, not that we know of. And we're not sure what the origin is of the organic matter that we have found so far on Mars. So, we call it regolith because it's not soil like we know it on Earth that has been processed over years by microbes and other life elements and there's not a significant amount of organic matter making it kind of a

• 15:47Chuck Nice?

  So he would have had a thyroid problem, so when they picked him up to save him, he basically would have had a goiter.

• 15:55Speaker 02

  Probably, or some other crazy issues. His metabolic system would have been having some weird issues because perchlorate, you know, actually kind of competes with iodine to bind on your thyroid. And we know that Mars has an abundance of perchlorate in the regolith. And that's actually something that, you know, I'm working on with other scientists. It's kind of funny, in my astrobiology life, I'm starting to kind of go back to my, to my human spaceflight roots and bringing my astrobiology knowledge and my human spaceflight knowledge together as we're getting ready to go back to Mars.

• 16:40Speaker 03

  Hi, I'm Ernie Carducci from Columbus, Ohio. I'm here with my son Ernie because we listen to StarTalk every night and support StarTalk on Patreon.

• 16:50Neil deGrasse Tyson?

  This is StarTalk with Neil deGrasse Tyson.

• 17:05Neil deGrasse Tyson?

  So Chuck, this is a cosmic query. So we put out the call, and so what did you get?

• 17:11Chuck Nice?

  Well, we got, we got a bunch of people who actually, believe it or not, are super interested in this subject.

• 17:20Neil deGrasse Tyson?

  I believe it, I believe it. It's like weirdly interesting, you know?

• 17:23Chuck Nice?

  It really is, it really is. Okay, let's start off with our, with our favorite. This is Violetta and her mom. It says, hello Neil.

• 17:33Neil deGrasse Tyson?

  Ain't that child grown up by now? Isn't she in college by now, Violetta? She, she used to write it when she was like 11 and 12, no, when she was 11 and 11 and a half, and 12, and 12 and a half.

• 17:44Chuck Nice?

  Okay, well, here we go. This is, hi Neil, hi Chuck, hi Kendra. Violetta here, the 13 and a half year old.

• 17:52Neil deGrasse Tyson?

  It's up to 13 and a half.

• 17:56Chuck Nice?

  A full up teenager.

• 17:57Neil deGrasse Tyson?

  Okay.

• 17:57Chuck Nice?

  So you said it, Neo. She did 11 and then 12, 12 and a half. Now she's 13 and a half.

• 18:04Neil deGrasse Tyson?

  And a half, alright.

• 18:05Chuck Nice?

  Okay.

• 18:07Chuck Nice?

  She says, I'm writing in from Washington DC. And my question is, what is the most surprising, fascinating life form or trait about a life form here on earth that you have discovered or learned about in your career so far? How did this impact the way you think about what life might look like elsewhere in the universe? Thanks, guys. And I just want to say to Dr. Lynch, that the world needs more scientists that look like you.

• 18:33Neil deGrasse Tyson?

  Whoa.

• 18:34Chuck Nice?

  By that she means fabulous.

• 18:37Neil deGrasse Tyson?

  Looking fabulous.

• 18:39Chuck Nice?

  And she says, thank you so much for doing and being an inspiration.

• 18:44Speaker 02

  Thank you so much, Bill, let us. So, oh my gosh, there's so many. There's so many crazy.

• 18:49Neil deGrasse Tyson?

  What's the weirdest bug out there? You probably have posters that rank the weirdest. Don't tell me that you don't know what your answer is.

• 18:58Speaker 02

  I'll give you my number one favorite because I just think it's so crazy. The thought of it is just so crazy. My favorite bug is, um, is the, um, is the one that can live on nuclear reactors. It's literally.

• 19:11Chuck Nice?

  And does it have a name?

• 19:12Speaker 02

  Yes, and I'm trying to remember.

• 19:14Neil deGrasse Tyson?

  It's not, it's not the tardigrade.

• 19:15Chuck Nice?

  It's not the tardigrade?

• 19:16Speaker 02

  It's not the tardigrade because tardigrade is not, it's a, that tardigrade is a, my quote, is a small organism, but it's a multicellular organism. It's, um, um, oh my gosh, my brain is, it's, uh, but it's.

• 19:28Neil deGrasse Tyson?

  Okay, but tell us more about it. So it can live like inside a nuclear reactor?

• 19:31Speaker 02

  They found it living on nuclear reactors. It could take these high doses of, of radiation and it's got this cool shape. It's actually kind of like a cube almost shape. And that's what I love about it.

• 19:40Neil deGrasse Tyson?

  In Japan, those things turn into Godzilla.

• 19:42Chuck Nice?

  I was gonna say.

• 19:44Neil deGrasse Tyson?

  That's how, that's how you got all those Japanese monsters.

• 19:48Chuck Nice?

  You're talking about a Marvel origin story right now.

• 19:51Neil deGrasse Tyson?

  Yes.

• 19:52Speaker 02

  So somebody, it's, um, um,

• 19:56Speaker 02

  oh, yeah, the name will come to me and I'll spit it out at some point later.

• 20:00Neil deGrasse Tyson?

  Okay.

• 20:00Speaker 02

  I know I will.

• 20:01Neil deGrasse Tyson?

  Alright, so you'd like the radiation resistance of that?

• 20:04Speaker 02

  I just, I just think it's amazing that, again, it's this whole thing about every time we think we got bugs figured out, like, okay, here's their radiation limit, here's their life-water limit, here's their cold limit, here's their hot, and then bugs are like, yeah, no, and they blow us right away, and they're like, nah, we figured out a way.

• 20:18Neil deGrasse Tyson?

  We got this, yeah, we got this, we got this. Alright, so, so is this, this a single-celled organism?

• 20:24Speaker 02

  Yes, it's a single-celled organism, yes.

• 20:25Neil deGrasse Tyson?

  Got it, okay.

• 20:26Speaker 02

  Most of the, most of the-

• 20:27Neil deGrasse Tyson?

  Whereas the tardigrade is a whole macroscopic object with legs and-

• 20:30Speaker 02

  Right, it's a multicellular organism, but it's still small and it's still something that has amazing, amazing resilience and, and can survive incredible, incredible environments. So, I'd be excited if we could find something like the tardigrade, like, on another planet, because it definitely has developed strategies to live in crazy environments. It kind of basically desiccates itself and, like, goes dormant and goes into, like, a, it's like, you know, it's, they call it a water bear, so it goes into hibernation, this really crazy, like, dehydrated hibernation, and it can survive all sorts of insane environments, including being exposed to space.

• 21:04Chuck Nice?

  Oh, man, there's a whole episode of Star Trek Discovery devoted to a space tardigrade that they find that helps them navigate the mycelium network, and the mycelium, cosmic mycelium network is this thing that allows you to move faster than light because you entered this network that kind of transports you almost instantaneously to different locations throughout the universe.

• 21:29Speaker 02

  I love it, I love it, and they found a tardigrade in there.

• 21:32Neil deGrasse Tyson?

  Who would have thought tardigrades were also spacefaring, well, if they came from space initially, that's the big thing there, yeah. Cool. Let's get to the next question, Chuck, what else you got?

• 21:42Chuck Nice?

  Alrighty, let's do it. Here we go, uh, this is, uh-oh, uh, Nander, S- Nander Sirkel.

• 21:54Chuck Nice?

  Okay.

• 21:55Speaker 02

  Okay.

• 21:55Chuck Nice?

  All right, that's your name now, man.

• 21:59Neil deGrasse Tyson?

  Take it or leave it, okay?

• 22:00Chuck Nice?

  Ah, here we go. He says, "I often wonder, when we're looking for life out there, aren't we a bit biased by our own conditions for life itself? Like water or breathable air? Even when considering silicon life forms, this still assumes creatures living on planets. Do you think it would be reasonable to consider, for example, other scales of life in size and spacetime? Maybe some life forms would be the size of planets, even galaxies or quantum particles moving in time so fast that we, as slow pokes, can't even see them."

• 22:44Neil deGrasse Tyson?

  Whoa. So Kendra, what part of your PhD thesis dealt with quantum?

• 22:49Chuck Nice?

  Quantum life forms.

• 22:51Speaker 02

  Uh, not much of it, but I'll tell you, I was a fan of Star Trek: Next Generation, so I'm there with this person's questions, you know? But quantum, quantum life forms, so not, not part of that. But in astrobiology, we really do think about, what we call as life as we don't know it, or what some people like to call weird life. And we try to think, when we're looking for life, we try to do, we're developing this way to try to think what we call agnostically about life, which means, so life as we don't know it or weird life. So yeah, there's the problem. We only have one data point, Earth and life, and life on Earth has these-

• 23:29Neil deGrasse Tyson?

  And even your extremophiles are part of that one data point.

• 23:32Speaker 02

  Even though they're extreme and they can live on radio, you know, live on reactors or breathe iron or, you know, eat other crazy, you know, metals and things like that.

• 23:46Neil deGrasse Tyson?

  Rocks.

• 23:47Speaker 02

  Eat rocks, yeah. And even though they can do these crazy things, they all still have the same amino acids as we do. They have the same stereochemistry as we do. And we all have the same fundamental, basically code. We have DNA and RNA. We all have the same fundamentals. We all have that same base code of life that kind of builds the structure of life. So yeah, when we think about life on another planet, we have to think about life as we don't know it. What if they, what if they use a completely different stereochemistry? What if they use a different set of amino acids to build- Their proteins, what if, you know, what if they have a different liquid? I was just getting asked this in a, in a previous conversation about, you know, what about Titan where we have lakes of methane? It's a fluid and life needs fluid for a chemistry and.

• 24:32Neil deGrasse Tyson?

  Titan, Saturn's largest moon.

• 24:33Speaker 02

  Yep.

• 24:33Neil deGrasse Tyson?

  Yeah, where we've actually been there.

• 24:34Speaker 02

  And we're sending a beautiful little helicopter that's gonna go and land and, and study on the surface and those lakes and some of the organic sands there and try to, try to understand the possibility for periodic chemistry on Titan. And that's the question is, is periodic chemistry possible in, you know, that kind of environment? And what would it look like? And what could life look like being, you know, arising in that kind of environment? So, yeah.

• 24:58Neil deGrasse Tyson?

  One, one of my favorite New Yorker comics was, uh, there's a crashed flying saucer in the desert and these two aliens are just crawling along the sands and one says to the other, ammonia.

• 25:12Speaker 02

  Total, I mean, that's totally it, right? I mean, it doesn't, I mean, on Earth, it just happened that water was the thing that was gonna be, you know, the basis for, for life's chemistry, but that doesn't necessarily mean that that's how it's gonna work on other planets. And that's something that we do have to think about. Um, you know, and then thinking about the larger scale of life, we do have scientists that are, you know, they look at things called techno-signatures. So we try to understand the scale of, you know, uh, contacting other intelligent, you know, what we call intelligent, I mean, forms of life and get me started on the intelligent comment, you know, I don't know.

• 25:43Chuck Nice?

  We, we're not even that yet.

• 25:45Neil deGrasse Tyson?

  Right, right. The jury's still out on that one.

• 25:47Chuck Nice?

  The jury's still out on us.

• 25:48Speaker 02

  Yeah, so, yeah, exactly. So.

• 25:51Chuck Nice?

  So can I ask both of you this?

• 25:53Speaker 02

  Mm-hmm.

• 25:53Chuck Nice?

  Um, is there a finite chemistry in the universe? I know we have the period, pretty periodic table. Is there anything that could be outside of that, that could actually contribute to life that is not on our periodic table?

• 26:12Neil deGrasse Tyson?

  No.

• 26:12Chuck Nice?

  No.

• 26:13Neil deGrasse Tyson?

  That can't happen.

• 26:13Speaker 02

  Everything, everything that we know. Now, there may be other elements that we haven't discovered just because we haven't discovered them yet, but no, I mean, because all life begins with stars, you know, you know, all of our elements come from stars, so. The star stuff, that's, that's the one common thing that makes it possible for us to really think about this question is that.

• 26:32Neil deGrasse Tyson?

  That's the ingredients in the kitchen.

• 26:33Speaker 02

  Yeah, that's the ingredients in the kitchen are the same across the universe. So that's helpful.

• 26:37Neil deGrasse Tyson?

  Right.

• 26:38Speaker 02

  Yeah.

• 26:38Neil deGrasse Tyson?

  It's just the recipe. We do, we're doing better than that because we have created elements that the universe has never seen before. In our laboratories.

• 26:47Speaker 02

  Yeah.

• 26:47Neil deGrasse Tyson?

  So we've, we, we created two dozen more elements or, or twenty, yeah, twenty, twenty, yeah, about two, twenty more elements than we're currently there. So, so let me, let me ask you this, um, Kendra. If chemistry is the same. And basically geology is the same. Right? You put a geologist on a planet, oh, I know what rock this is, or we might have a different kind of minerality, but it, it won't be so foreign to them that they'll be befuddled. Right. Is there any reason, and, and the physics is obviously the same. So if I have the same physics, the same chemistry, the same geology.

• 27:26Neil deGrasse Tyson?

  Why can't we think that maybe biology will go, will all focus towards the same forms as we have here? If everything else does that in the other branches of science?

• 27:38Speaker 02

  Well, I mean, that's a, that's a loaded question because it's not.

• 27:44Speaker 02

  It, it's, um, I mean, we can expect some of the same, uh, principal things to happen. Like there's going to be a, some kind of cell wall structure. There's going to be an encoding system. There's going to be some way to transfer information. There's going to be some way to move energy and generate energy. There's going to be some way to move things in and out of an interior environment. Those kinds of things, yeah, we can kind of figure out that those kind of are the common elements that are going to make life happen for biology. And those are the kind of things that we agree there. We agree that, we actually kind of agree there's a common set of, of about, about eight things that all life. You know, anything we call life would probably have going on. Now, how they get it and how they put it together, that's where that chemistry is different.

• 28:26Speaker 02

  And that's where the, the environmental context that made the geology is probably different. You know.

• 28:32Neil deGrasse Tyson?

  That's gonna matter.

• 28:32Speaker 02

  And that's where, you know, you know, and that's where may- maybe some of the physics because the gravity is a little different. So some things are slightly different that help, you know, drive that environmental context. So does that make sense?

• 28:44Neil deGrasse Tyson?

  I can say that you're not gonna expect life forms the size of galaxies.

• 28:48Speaker 02

  No.

• 28:48Chuck Nice?

  Well, okay.

• 28:49Neil deGrasse Tyson?

  Can I tell you why? I'll tell you why.

• 28:50Chuck Nice?

  Why?

• 28:50Neil deGrasse Tyson?

  Okay. Okay. So again, our galaxy is a hundred thousand light years across. Okay? Hundred thousand. If that were a life form and one part of it had an itch,

• 29:03Neil deGrasse Tyson?

  how long would it take to scratch that itch? If you can't, you can't move faster than the speed of light. So, so it has an itch and then it brings one part of it to over to the other part to scratch it. A hundred thousand years later, it scratches the itch. This is not.

• 29:20Neil deGrasse Tyson?

  This is not a, uh, this is not a coherently functioning organism.

• 29:24Chuck Nice?

  Right.

• 29:25Speaker 02

  Exactly.

• 29:25Neil deGrasse Tyson?

  And if evolution requires a lot of experimenting, then the life form has to be able to change either on purpose or by accident, fast enough so that you can have enough of these experiments for it to take on interesting forms.

• 29:39Speaker 02

  Yeah.

• 29:40Neil deGrasse Tyson?

  And, and if you're really, really big, that doesn't happen.

• 29:42Speaker 02

  Yeah, because I mean.

• 29:43Chuck Nice?

  And if it takes a hundred thousand years to scratch an itch, just imagine how uncomfortable it would be when its underwear gets stuck in its butt.

• 29:54Neil deGrasse Tyson?

  Okay.

• 29:58Speaker 02

  I'm, I'm more thinking about the size of the underwear at this point, you know, so to say.

• 30:01Neil deGrasse Tyson?

  I know.

• 30:03Speaker 02

  Sorry.

• 30:06Neil deGrasse Tyson?

  Well, just, just to be clear, I wear boxer briefs and boxer briefs don't get stuck in your butt.

• 30:09Chuck Nice?

  Oh.

• 30:10Neil deGrasse Tyson?

  Okay.

• 30:10Chuck Nice?

  Oh, look at you, sexy bragging.

• 30:18Neil deGrasse Tyson?

  So let's see if we can squeeze one more in before the break.

• 30:19Chuck Nice?

  Alrighty, let's do it. Here we go. This is Akilisha, uh, Kashyap. Man.

• 30:33Chuck Nice?

  Y'all just messing with me now, man. That ain't a real name. Okay, it's A K H I L E S H. Achilles. Achilles. Kashyap. C K A S H Y A P. Kashyap, I hope. Okay.

• 30:49Neil deGrasse Tyson?

  Okay.

• 30:51Chuck Nice?

  Hello, Dr. Tyson.

• 30:52Neil deGrasse Tyson?

  We'll give you a B minus on that one.

• 30:53Chuck Nice?

  I get an A minus, okay.

• 30:55Neil deGrasse Tyson?

  A B minus.

• 30:55Chuck Nice?

  Oh, B minus, damn. You just keep, I keep going down. Before you know it, it's just like, you're expelled.

• 31:04Chuck Nice?

  Hello, Dr. Tyson. Hello, Dr. Lynch and Lord Nice.

• 31:07Neil deGrasse Tyson?

  Oh, okay.

• 31:08Chuck Nice?

  Uh, I'm, I'm a first time Patreon member.

• 31:13Neil deGrasse Tyson?

  Nice.

• 31:13Chuck Nice?

  And my question is, if we discover life on a restricted body like Europa or Enceladus, are we allowed to study them only through orbiting satellites? Or can we bring something back home and cut them open? For science, of course. I mean, you went dark there. You went dark at the end, bro.

• 31:37Chuck Nice?

  You, you started off with, uh, to-

• 31:40Neil deGrasse Tyson?

  Real good.

• 31:41Chuck Nice?

  You started off with our continuing mission.

• 31:47Chuck Nice?

  To seek out new life, new civilizations, and then you ended up with, let's just cut these suckers open.

• 31:55Neil deGrasse Tyson?

  Well, well, be careful. There's some folks around where Kendra hangs out in Texas where, can we bring it back and barbecue it?

• 32:03Speaker 02

  Yeah, yeah.

• 32:05Neil deGrasse Tyson?

  We will, we, we will get to that answer after, after the break on StarTalk Cosmic Queries with astrobiologist Kennda Lynch.

• 32:24Neil deGrasse Tyson?

  We're back for the third and final segment of StarTalk Cosmic Queries. Kennda Lynch is with us. She's an expert in microbes on Earth. As possible analogues to microbes in the universe. So, so, uh, Kennda, uh, over the break, you, uh, you remembered this, this, uh, radioactivity-loving microbe.

• 32:46Speaker 02

  Yes.

• 32:47Neil deGrasse Tyson?

  The name of it, what, what's it called?

• 32:48Speaker 02

  It's called Dinococcus radiodurans, and they love, they literally can live on, um, they found them on nuclear reactors, and they are very, um, you know.

• 32:57Neil deGrasse Tyson?

  Dinococcus?

• 32:58Speaker 02

  Dinococcus, Dinococcus, yes.

• 33:00Neil deGrasse Tyson?

  Radiodurans, this sounds like a, a rock group.

• 33:03Chuck Nice?

  It does.

• 33:04Neil deGrasse Tyson?

  Doesn't it?

• 33:04Chuck Nice?

  It really does, you know?

• 33:07Neil deGrasse Tyson?

  Chicago, are you ready?

• 33:12Neil deGrasse Tyson?

  Dinococcus radiodurans.

• 33:15Speaker 02

  Rock it out.

• 33:18Chuck Nice?

  Wow, that's cool.

• 33:20Neil deGrasse Tyson?

  Okay, so we left off with a question about, what was it, Chuck?

• 33:24Chuck Nice?

  So, uh, he wants to know that if we discover life on a restricted body, like Europa or Enceladus.

• 33:33Neil deGrasse Tyson?

  It's protected by NASA laws, basically, yes.

• 33:36Chuck Nice?

  Right, so, you know, can we actually study it just through satellites orbiting? Or can we bring back something and cut it open?

• 33:48Speaker 02

  Well, I mean, um, you know, to cut it open, wow. Uh, so, I mean.

• 33:54Neil deGrasse Tyson?

  Well, let me just back up for a second. So NASA has a department of planetary protection. And there, there's, there's, there's a, there's a code within them, which is, not, not a computer code, but a behavioral code, whereas there are these selected objects in the solar system that may have life. We don't mess with them, or if we do, we go in a highly, highly sterilized way. And if we bring anything back to Earth, we want to keep that quarantined to make sure it doesn't kill us. That's their job.

• 34:22Speaker 02

  Yeah, and that's the, that's the planetary protection office. And the answer is, we're moving into this phase of science where we are trying to bring things back, because we realize that we need to bring things back to be able to study them better, to understand if there's life in them or not. Right now, we're in the process with the Perseverance rover in the, um, in Jezero crater for the Mars 2020 mission. They're caching samples that we're gonna send to. A lander to go and pick up those samples and hand them off from the rover. And we're going to bring those samples back to Earth from Mars. And we actually are have missions that are being developed to go to try to land on both Europa and Enceladus. Enceladus is my favorite. It's one of my favorite icy moons, by the way. I love Enceladus. Um, to try to understand, um, to look at the surface and maybe eventually try to get a sample,

• 35:06Speaker 02

  a sample that that came up from the subsurface ocean on both of those planets. Uh, you know, that we can, we can study in C2 and maybe someday we can figure out how to bring those back. But right now, the goal is to just try to get to land on the surface and try to study samples in C2 to see if we can find evidence for, for possible, um, biosignatures of life.

• 35:26Chuck Nice?

  Uh, so I may be mistaken with this question, but I'm just going to ask it. Uh, did, did we not learn from what's Madame Saturn, what Carol, Carolyn Porco? That they're going to try to fly something through one of the plumes?

• 35:40Speaker 02

  Yes.

• 35:41Chuck Nice?

  Of Enceladus and maybe collect?

• 35:44Speaker 02

  Yes.

• 35:44Chuck Nice?

  What's being, you know, pushed out of the, uh, the ice?

• 35:47Speaker 02

  Yeah, we have a, we have a mission that's going to try to do that. I, um, well, we also have, uh, Europa Clipper that's going back to Europa. Um, that's gonna, that's gonna, that might even be able to do that with Europa Clipper. But we're also trying to fly through the plumes of Enceladus. We have the Enceladus Orbilander concept that is looking at doing that, like orbiting, but also sending a lander down to the surface to pick up, to, to do some in C2 science on the surface of Enceladus, hopefully near one of the tiger claws where all this stuff is pewing out.

• 36:14Neil deGrasse Tyson?

  Okay, so that's, that's the third time you said in situ.

• 36:17Speaker 02

  Sorry.

• 36:18Neil deGrasse Tyson?

  In five sentences.

• 36:19Speaker 02

  In C2 means?

• 36:21Neil deGrasse Tyson?

  In situ, excuse me, Madame Latin there.

• 36:24Speaker 02

  Sorry, Latin, that's all science, especially biology. We like, we like throwing Latin around everywhere.

• 36:29Neil deGrasse Tyson?

  You throwing Latin?

• 36:31Speaker 02

  Everything has a Latin name.

• 36:32Neil deGrasse Tyson?

  Just give me some Latin.

• 36:33Speaker 02

  Everything has a Latin name in biology.

• 36:34Neil deGrasse Tyson?

  Yeah, yeah, it's Latin. So, so let me emphasize something that I think you, you said, but just wafted by it. Um, the, the ice on Europa is very thick. But it also cracks and then water seeps up in the cracks and refreezes. So you're going to be? You're gonna be astrophysically lazy and instead of trying to dig through the ice, you're gonna try to see if there's anything that came up through the ice and froze there that requires no digging at all.

• 37:02Speaker 02

  Well, I mean, yeah, I mean, there's, it might require some digging for the, you know, the subsurface, but there are, you know, we have some really brilliant scientists, not me, but some of my colleagues that are really brilliant that study the kind of the ice.

• 37:13Neil deGrasse Tyson?

  Other brilliant scientists.

• 37:15Speaker 02

  Other brilliant scientists, not me, because I don't study ice dynamics, I'm a, you know, I'm the biology one, but they study kind of that geology of those ice dynamics and they found that that there is likely water that is seeping up from the ocean and kind of connecting in the shallow subsurface and doing things that they can actually see on the surface from remote sensing.

• 37:34Neil deGrasse Tyson?

  And if that water below the surface had life, it would have gurgled up and frozen in place, you'd have freeze dried life to study.

• 37:40Speaker 02

  Yeah, exactly, if we can access some of those areas where that life probably kind of gurgled up, and then on solid, of course, we've got, you know, the tiger claws just spewing, you know, stuff out into space so we can try to capture some of that, and then we can also land on the surface to try to see what we can see that maybe kind of fell back down, if anything, you know.

• 37:57Neil deGrasse Tyson?

  Okay, so how sterilized do your probes have to be to land on a protected body?

• 38:01Speaker 02

  Oh, very sterile, that's the challenge of doing this, is that, yeah, you've got to make sure not only that the lander is very sterile, but that, you know, all the instruments that you're working on are very sterile.

• 38:12Neil deGrasse Tyson?

  Everything, everything.

• 38:13Speaker 02

  And they're even working on concepts.

• 38:15Neil deGrasse Tyson?

  A coronavirus found on?

• 38:17Speaker 02

  Yeah.

• 38:18Chuck Nice?

  Just make the lander wear a mask.

• 38:20Neil deGrasse Tyson?

  That's everything, Chuck.

• 38:23Chuck Nice?

  It's just like, make sure you wear your mask, lander.

• 38:26Speaker 02

  And use hand sanitizer, right?

• 38:27Chuck Nice?

  Use hand sanitizer and show us your vax card before you touch that.

• 38:31Speaker 02

  So, yeah.

• 38:34Neil deGrasse Tyson?

  All right, Chuck, give me another one, another question, Chuck.

• 38:36Chuck Nice?

  All right, you know what, I gotta ask this just before we go, I know I'm not a Patreon, but, so when you talk about this water underneath this, basically, you know, this planet, you got the ice like a crust and then the water underneath, but then you have other bodies in space that are just frozen, solid pieces of water, why doesn't the planet just freeze all the way down? Why is there water underneath that ice that can just?

• 39:05Neil deGrasse Tyson?

  On the moons.

• 39:06Chuck Nice?

  Yeah, on the moons, not the planet, I'm sorry.

• 39:07Speaker 02

  Why do we have these ocean worlds on moons around Jupiter and that?

• 39:11Chuck Nice?

  On moons.

• 39:12Speaker 02

  Well, first of all, a couple of different things. First, first of all, um, there is, um, we get heating from the gravity, the extreme gravity that causes what we call tidal heating and, and, um, and Neil could probably explain that better, that, that kind of pushes and flexes and causes heating that kind of adds some heating to the planet and keeps it warm. Plus, these waters have lots and lots and lots and lots of salt, lots of salt, that are keeping, that are depressing the freezing, the, the, the, the, the freezing point. So the salt, the water is able to stay liquid because there's so much salt in it that that freezing point gets lowered because there's so much salt in it keeping it liquid.

• 39:48Neil deGrasse Tyson?

  It's been rumored that zero on the Fahrenheit scale is the freezing temperature of a super saturated solution of, of, of brine, of, of, of salt water. It's been rumored. Um, and so that's where we get a zero. That's the coldest liquid they could get that would freeze. And then regular water just goes freezes at the warmth of thirty two degrees on a, on the Fahrenheit scale. But yeah, no, you said it perfectly, uh, Kennda, just the tidal stress between Jupiter and the tugs of other surrounding moons are pumping energy in. And so now there's a heat source that has nothing to do with the sun. Um, I learned in my biology books, you need sunlight for life. What you really need is just energy. You take the physics angle on, you just need energy and

• 40:32Neil deGrasse Tyson?

  you pump energy in from, from tidal forces, you got it.

• 40:35Speaker 02

  And what they think's going on in Enceladus is they actually think that heat is also generating kind of, and maybe it's maybe some residual heat, but probably more of the tidal forces on Enceladus, generating heat that's causing hydrothermal, hydrothermal vents, like what we see on Earth, you know, the deep sea hydrothermal vents with the black smokers and things that you see like on the National Geographic videos. They think that that's what they're seeing in the, uh, in Enceladus, and that's kind of what's kind of helping to kind of possibly generate the tire claws pushing, pushing that energy out. And that is creating a lot of cool chemistry that life can live, that life could take advantage of.

• 41:05Neil deGrasse Tyson?

  So, Kennda, we've had Natalie Starkey on the show who, who wrote a book recently on, uh, all the- Cool, literally and figuratively, things in the universe. Volcanoes, hot and cold. And she describes, and sell it as, as an ice volcano. Yeah, cryovolcanism. And, and the plumes are just, where you just need extra pressure buildup. It didn't have to be hot compared to us. It could just be pressure in its own environment, even if it's very cold. So, very cool. Chuck, keep it coming.

• 41:33Chuck Nice?

  You can't get better than that. That's so cool. Cryovolcanism.

• 41:38Neil deGrasse Tyson?

  Yes.

• 41:38Chuck Nice?

  If that doesn't, if that doesn't make you love science, you're dead inside.

• 41:43Neil deGrasse Tyson?

  I want that on my business card.

• 41:44Chuck Nice?

  Exactly.

• 41:45Neil deGrasse Tyson?

  I'm a cryovolcanist. What are you?

• 41:49Chuck Nice?

  All right, here we go. This is William D.A. Thank you, William. Thank you.

• 41:59Chuck Nice?

  He says, "Given that humans have always been fighting a war with tiny bacteria, viruses, and preons, etc., how likely do you think it is that there's a planet out there with a tiny microscopic organism, and it wiped out the more complex life? What would such a planet look like long term?" And that's what he said. So if we're in a war with, i- i- if we all got killed by a virus here, then what happens long term, even if it's just here on Earth?

• 42:39Neil deGrasse Tyson?

  Yeah, ultimately, do all the little things kill all the big things? And you just have a planet full of viruses? Or single-celled organisms? Yeah, what, what is it, where does biology go?

• 42:49Chuck Nice?

  Hey, what's up Corona? What's up streptococcus?

• 42:56Neil deGrasse Tyson?

  Hey, rhinovirus, how you doing today? Yeah, everybody's just chilling.

• 43:00Chuck Nice?

  All the viruses.

• 43:00Neil deGrasse Tyson?

  They got cities and things.

• 43:02Chuck Nice?

  Get out of here, herpes!

• 43:08Neil deGrasse Tyson?

  You weren't invited to the party.

• 43:09Chuck Nice?

  No, you're not invited, man.

• 43:13Speaker 02

  Um, you know, given that we've already had multiple mass extinction events on the planet already, um, where we've, where like, not necessarily microbes have taken out our bigger organism, but something else usually an asteroid or something else took out, um, our larger organisms, uh, life has just kind of rebounded. And yeah, for a while, the, the little guys were, you know, the little guys were in charge, but life eventually kind of picked back up and, and, and organisms got more, you know, there, there's an advantage on earth for multi-cellular, multi-cellularity. And so life eventually kind of worked its way back to, um, multi-cellularity at some point, you know, and those small guys got bigger and bigger and more complex

• 43:55Speaker 02

  and more complex each time. But we, you know, so, um, all I would say is if we had a micro-generated mass extinction event, my guess is yeah, for a while the little guys would be in charge, but then eventually, um, you know, depending on, you know, the environment of earth, if it's advantageous to take advantage of resources and to keep yourself alive, become multi-cellular, life would probably go back to being multi-cellular or having a multi-cellular component on the planet.

• 44:20Neil deGrasse Tyson?

  That's an excellent argument because if we've done it multiple times in the past, why not again? I mean, after the KT extinction, nothing bigger than, you know, a suitcase or something, you know?

• 44:31Speaker 02

  Yeah, like swirls and rats and like small

• 44:32Neil deGrasse Tyson?

  Yeah, a duffel bag, which is biggest sized life form. And now we have, you know, the blue whale swim in the ocean, the largest animal there ever was. So a very good argument there. Yeah, I'm with you on that.

• 44:42Chuck Nice?

  That's very cool.

• 44:43Neil deGrasse Tyson?

  Okay. Chuck, we got time for like one more, I think. What do you got?

• 44:46Chuck Nice?

  All right, let's, uh, let's go to Kevin, the sommelier.

• 44:52Neil deGrasse Tyson?

  Oh.

• 44:52Chuck Nice?

  Kevin says. I like Kevin. Yes.

• 44:56Neil deGrasse Tyson?

  Kevin, we're gonna party with you, Kevin.

• 44:57Chuck Nice?

  Hey.

• 45:00Chuck Nice?

  Kevin says, you know, when I'm sitting around drinking a Chateau Neuf de Parc, I often

• 45:04Neil deGrasse Tyson?

  But no, did he say?

• 45:05Chuck Nice?

  No, he doesn't, no.

• 45:06Neil deGrasse Tyson?

  No, no, no.

• 45:09Chuck Nice?

  I just, I just threw that in there.

• 45:11Neil deGrasse Tyson?

  Okay.

• 45:11Chuck Nice?

  I thought that'd be cool.

• 45:13Neil deGrasse Tyson?

  That was cool.

• 45:13Chuck Nice?

  I wish he did start like that. Uh, Kevin says astrobiology used to be termed exobiology. Was this just a rebranding to make people more interested in it? Like when Coke introduced new Coke, but had, but had to go back to classic Coke? Well, keep drinking up, Kevin the sommelier.

• 45:37Speaker 02

  That's a very good question that I'm thinking about here because you know, the reality is, is that when I fell in love with this, it was exobiology when I was, and I'm not going to date myself, but when I got my first lecture, it was from this gentleman named Donald DiVincenzi, who was a part of what was called the exobiology office at NASA. And FYI, NASA always had an exobiology office. NASA started with an exobiology office. So this has been a question that NASA has wanted answered since the beginning of NASA. So this has been kind of part of our charter from the beginning. And so I think the big transition came, obviously after the Viking results, but I think the big transition came after the Allan Hills Rock and the discovery

• 46:19Speaker 02

  of the organics in the Allan Hills Rock and, you know, the hypothesis that these were, organics were made by Martian microbes and these kind of microbes made these special, you know, the whole argument about the biogenicity of the organic structures in the Allan Hills.

• 46:39Neil deGrasse Tyson?

  The Allan Hills Rock is about the size of an Idaho potato, been sitting on the shelf for years. We knew it was a meteorite, but no one really knew much about it until, like you said, the Viking mission, we have accurate measurements of the atmosphere of Mars from that mission and air pockets trapped in that rock matched that air exactly. And oh my gosh, a rock from Mars sitting on the shelf.

• 47:00Speaker 02

  The age of SNC rocks, meteorites was born.

• 47:03Chuck Nice?

  I never mind looking ignorant because it's my specialty.

• 47:08Chuck Nice?

  Please tell me what the Allan Hills Rock is.

• 47:10Speaker 02

  The Allan Hills is a Mars meteorite. We know, as Neil said, that it came from Mars because we look at these little, little bubbles in it that keep gases in it and we're able to extract the gas and look at the gas composition and it tells us it has the exact same composition of the gases on Mars from our Viking results. And so we know that this meteorite was a piece of Mars that got blasted off and traveled to Earth and kind of landed on Earth. And so Allan Hills is one of what we call an SNC or a Mars meteorite that came from Mars.

• 47:39Chuck Nice?

  Cool.

• 47:40Neil deGrasse Tyson?

  Just for background, there's a set of hills in Antarctica called the Allan Hills, where the glacier that is like permanently on Antarctica for now, as it migrates, it comes up against the hills. And if any rock fell from space and landed on this glacier, it gets dragged to these hills and deposited there. So it's a really convenient way to scoop up meteorites without having to comb thousands of square miles of area. You let the glacier do it for you. So it's in Allan Hills and was found in 1984.

• 48:18Speaker 02

  And they do still do annual trips, or they had been, I don't know if they stopped because of COVID for a while, to Antarctica to go out and look on the glaciers for meteorites. Because anywhere else, you actually have to watch it fall to kind of go look for it, or you have to, you know, and we've had, we have people send us rocks, especially at the LPI, all the time. "I think it's a meteorite!" And it's not.

• 48:38Neil deGrasse Tyson?

  Yeah, it's here we call them meteor wrongs.

• 48:40Speaker 02

  Yeah, exactly.

• 48:42Neil deGrasse Tyson?

  No, the point is, is it most? Certainly, possibly as much as half of all meteorites in our collections come from these ice sheets. And people wonder, well, do the meteors aim for the ice sheets? No, that's the only place you would find them if they fell. Otherwise, you have to sift through countless other rocks in the forest to know which one came from space and which didn't.

• 49:04Speaker 02

  And most of the ones that are verified that weren't falling on the glacier is because somebody watched it fall and tracked it.

• 49:08Neil deGrasse Tyson?

  Yeah, exactly.

• 49:09Speaker 02

  So, but the point is that after, you know, we got Allan Hills, and this was back in, I think it was 92, 93, is that right? When this study came out, and they thought that this happened, and everybody, you know, kind of disagreed, and we had, you know, arguments back and forth about are they life, are they not life? And then we realized, do we really understand what life is? And this is about the time that we started learning about, we started learning more about extremophiles and the RNA world, the vastness of the RNA world. And we started learning more about biotechnology and our capabilities for, you know, for, you know, higher sample resolution and sample detectability, you know, and our instruments got higher. So all of this kind of stuff made us start to question.

• 49:54Neil deGrasse Tyson?

  My instruments got more sensitive.

• 49:55Speaker 02

  Yes, thank you, more sensitive. Can't find my words today.

• 50:02Speaker 02

  But all of these things kind of together, kind of, you know, with that Alan Hills discovery, and at that time, they went back and looked at the Viking results and and realized that Viking would not have necessarily caught everything because of the the sensitivity wasn't high enough, right? So there's all of these things going on. And, you know, we started asking the question like, what do we really know about life? Do we really understand life on Earth? Do we really understand the extent of life or what is alive on Earth? And so that's where astrobiology, because it was looking, exobiology was like looking for life elsewhere, but astrobiology includes understanding how life on Earth also came to be. How did we become to be a living planet? So that's where the new term astrobiology came from, because it became about looking

• 50:45Speaker 02

  for life on Earth, looking for life in the universe, but also trying to understand how do we become the data point that we have now?

• 50:51Neil deGrasse Tyson?

  So I take the meta view, which is everything the astrophysicist does in space has a counterpart here on Earth. And so you want to glue together astro in front of each of those words. So we have astrochemistry, astrobiology, astroparticle physics, and so astro, we're the pushcart for it all.

• 51:10Speaker 02

  Right, there you go. I like that one, too.

• 51:13Chuck Nice?

  Funny how the astrophysicist become the quarterback of the team.

• 51:19Speaker 02

  Oh, I get it.

• 51:21Neil deGrasse Tyson?

  We got appointed by the universe itself to be that role.

• 51:25Speaker 02

  Come on, now.

• 51:27Neil deGrasse Tyson?

  So, Kendra, I remember when that Allan Hills rock made news, and it was a research paper by some folks at Johnson Space Center, making the claim that maybe this has evidence for life, which meant life was on Mars. I remember it like it was yesterday. And there was some chemistry within the rock, and then there was a, there was a photo of a worm looking thing on the surface. And we didn't know what it was. It was really tiny, but it was just kind of intriguing. It made a good headline photo. But the the better evidence was from the other chemistry going on in the rock. I was on a talk show to comment on this rock, and they had me, a philosopher, and a biologist.

• 52:10Neil deGrasse Tyson?

  And the philosopher said, how do we know whether the rock itself is not alive? Okay, we got that out of the way. Got to make that comment.

• 52:17Chuck Nice?

  Stop smoking weed, dude.

• 52:21Neil deGrasse Tyson?

  We had to get past that. And then... So then they put up the photo of this worm thing and the biologist says, "That can't possibly be life." And I'm thinking, "Wow." The biologist must know a lot to know that that can't be... So I said, "Well, how come?" And he says, "Oh, because that's one tenth the size of the smallest microbes on Earth." And I then said, "Last I checked, this is from Mars." It was like, and I realized how narrow the thinking was of biologists. Because like you began this program, Kendra, if all you have is a data sample of one,

• 53:03Neil deGrasse Tyson?

  you have no capacity to think differently. Everything has to be shoehorned into your own understanding of the world. And I was perfectly happy to have it be a life form that we don't know anything about. Deal with it.

• 53:16Chuck Nice?

  And that biologist today is working at McDonald's.

• 53:24Speaker 02

  I don't remember who that was.

• 53:26Neil deGrasse Tyson?

  All right.

• 53:26Speaker 02

  I don't know.

• 53:27Neil deGrasse Tyson?

  We gotta call it quits there. Kendra, it's been a delight to have you on the show. I remember you when you were in graduate school and you're all grown up now. It's so fishy, all grown up.

• 53:37Speaker 02

  It's such an honor to be here and I'm so glad that you remember me and...

• 53:40Neil deGrasse Tyson?

  Actually, we finally found you in the ether. And we can find you on Netflix, Episode 2 of Alien World. And we're loving it. And Chuck, always good to have you there, my co-host.

• 53:52Chuck Nice?

  Always a pleasure.

• 53:53Neil deGrasse Tyson?

  All right, Emile deGrasse Tyson here, your personal astrophysicist. Keep looking up.