Pod Insights StarTalk Podcast Cosmic Queries – Volcanoes & Life in the Universe About this episode Have we disproven the idea of a “goldilocks zone”? Neil deGrasse Tyson and comedian Paul Mecurio learn about space geology, magnetic fields, volcanoes, and the origins of life with cosmochemist Natalie Starkey, PhD.
Transcript 10,116 words · 4 speakers
Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.
0:01 Neil deGrasse Tyson? 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, and this is gonna be a Cosmic Queries edition. I don't know if you know the history of this. We did it on a lark some years ago, because questions would show up in our inbox, and we said, "Why don't we sort of staple them together and make an episode out of it?" And it turned out to be very successful. Now, you can only ask questions officially if you are a member of our Patreon network.
0:46 Neil deGrasse Tyson? But you can do that at the lowest entry level that we have, which is like $5 a month. I got with me my co-host, Paul Mecurio. Paul, how you doing, man?
0:56 Paul Mecurio? Hello, Neil. Great to be back. You're doing great, man.
0:59 Neil deGrasse Tyson? Yeah, I think $5 a month, everybody should be able to have $5.
1:02 Paul Mecurio? You know, unless you're going to the track. The track still exists. Yeah, that's $5. That's a cup of coffee at Starbucks.
1:11 Neil deGrasse Tyson? Yeah, I know, that's right. That's all. For a month, right. That's all that is.
1:15 Paul Mecurio? One less coffee, that's all.
1:16 Neil deGrasse Tyson? Well, today, we are orbiting the solicited Cosmic Queries around the expertise of a friend and colleague from across the pond, Natalie Starkey. Natalie, welcome back to StarTalk.
1:30 Natalie Starkey? Oh, thanks for having me. It's always good to join you guys.
1:33 Neil deGrasse Tyson? We love the accent. We love the accent. Oh, my gosh, we love it. Okay.
1:39 Natalie Starkey? I can't help it.
1:41 Paul Mecurio? I don't feel that sophisticated right now.
1:44 Neil deGrasse Tyson? Yeah, we just feel so inadequate.
1:47 Paul Mecurio? I know, exactly.
1:50 Neil deGrasse Tyson? So, let me remind people of Natalie's expertise. As I said, not only a friend of StarTalk, she's an ace science communicator, and she's a science media producer at the Royal Society of Chemistry in Cambridge. That would be Cambridge, England. She's written two books, Catching Stardust, I love it, and Fire and Ice. And it has a paperback edition that's coming out very soon. And... She wrote our planetarium show here in New York City at the American Museum of Natural History, and that show is called Worlds Beyond Earth.
2:28 Paul Mecurio? I've seen that show, and I remember saying to myself, there are flaws in this show. And I wanted to talk to you about it. Hang on a second. What did you mean when you said?
2:38 Neil deGrasse Tyson? So this is the right moment for this, yeah.
2:40 Paul Mecurio? I asked my wife, I walked out, I'm like, I cannot, I don't know who wrote this.
2:46 Neil deGrasse Tyson? Yeah, excellent, and I love the two topics remind us what catching stardust was about. Was that the Stardust mission?
2:51 Natalie Starkey? Well, it does feature within it, because I worked a little bit on the Stardust mission when I was doing lab work. But it focuses mostly on comets and asteroids just in general. So I look at some of the missions that have been to comets and then talk about sort of the past, the history of comets and asteroids, and also then going to the future. What are we doing with them in the future? How are we gonna divert them from colliding with Earth? Or how are we gonna use them to mine them for precious metals and things?
3:17 Neil deGrasse Tyson? Now, you realize there was a hit bestselling book and hit movie on exactly this subject, alright?
3:24 Natalie Starkey? There's been many books.
3:26 Neil deGrasse Tyson? No, no, I'm sorry, not just the collision part. But I think Michael Crichton's first novel was The Andromeda Strain.
3:33 Natalie Starkey? Oh, was it? Okay.
3:34 Neil deGrasse Tyson? I think it was, where there's a piece of sort of space dust that we captured and brought back to Earth. Because wasn't the Stardust mission, we brought comet dust back to Earth?
3:43 Natalie Starkey? Yeah, so Stardust, yeah, that was the first sample return mission from a comet. So, yeah, exactly.
3:50 Neil deGrasse Tyson? So as any good science fiction movie or story unfolds, we go into space and something bad happens. So, that's the whole plot.
4:00 Paul Mecurio? Well, it wouldn't really be much of a movie to stay and watch. It's like, well, we went to space, everybody was very pleasant, and they gave us tea, and then we left.
4:07 Neil deGrasse Tyson? And we analyzed the sample in a lab, let's catch up with what's in the lab.
4:11 Paul Mecurio? Exactly, exactly.
4:13 Neil deGrasse Tyson? So you didn't bring back any killer bugs, I guess, unless that was COVID.
4:19 Natalie Starkey? It was far too long ago. No, I mean, but they did bring back amino acids, which is really cool. So like, what a lot of people don't realize is that comets and asteroids contain basically the building blocks for life. And so actually, they measured glycine, which is one of the amino acids, within the cometary samples that were collected by stardust. And they didn't know it at the time. They were worried it was actually contamination that had been brought about from the scientists handling the material. But then since then, we've analyzed other comets and space and samples of comets, and we've seen it there again. So we know that actually the stuff that was on the stardust samples was amino acids in space, which is really cool when you're thinking about life elsewhere in the solar system.
5:00 Neil deGrasse Tyson? You said it just casually, but it's a very big challenge to make sure that we don't contaminate the samples that we're analyzing.
5:07 Natalie Starkey? Yeah.
5:07 Neil deGrasse Tyson? And say, look, there's DNA. Hey, look, there's the rhinovirus. Hey, there's the, you know, oh, there's frogs.
5:13 Paul Mecurio? Right. Why don't you have your gloves on? How many, how many times do I have to tell you this?
5:19 Neil deGrasse Tyson? Here's a box of Kleenex, you know?
5:22 Paul Mecurio? Can you stop sneezing on the, on, the dust is making me sneeze.
5:28 Neil deGrasse Tyson? Yeah, so that's a whole branch of NASA, I think. Planetary Protection, right?
5:34 Natalie Starkey? Yeah.
5:34 Neil deGrasse Tyson? They have a whole division called Planetary Protection, where we don't forward contaminate where we're gonna explore. And we wanna make sure contamination doesn't come back to Earth.
5:43 Natalie Starkey? Precisely, so, yeah, because if we send a spacecraft up into space and we wanna land it on a planet or a moon or a comet or asteroid, we don't want to then take bugs from Earth and then put them on that place and go, oh, look, we found these bugs here. We need to know that that's perfectly clean before we do that. So that's why we don't just go out and just put things on different planets and things. That would be relatively easy to do, but we need to make sure that we're protecting where we're going. And equally, the other way around, we need to make sure what we bring back doesn't end up with Earth bugs on it, and we don't know where they've come from.
6:12 Neil deGrasse Tyson? Right.
6:13 Paul Mecurio? At the risk of a silly question, so the amino acids that were found, I know there are amino acids here because I hear about them. Are they different than the amino acids that exist on Earth?
6:24 Natalie Starkey? Great question, really good question. Actually, there's more amino acids in space than we have on Earth. There's more amino acids than we need for life as we know it. So actually, now we've been analyzing those different meteorites, which is pieces of space rock that have landed on Earth and other samples from space. We've discovered a whole raft of amino acids, way more than we need. So it might be that they're not all needed for life, but they just exist anyway.
6:48 Neil deGrasse Tyson? Wait a minute, Natalie, I think you're taking the extra amino acids and making life forms of your own.
6:53 Natalie Starkey? Well, maybe. And that's what we're yet to find out. But you know the potential's there, you know. So in any of these moons or comet clusters, maybe there's, you know, there are different forms of life that we don't know at the moment. So yeah, there's so much out there.
7:09 Paul Mecurio? Her neighbors are like, is it me? Are there like six or seven more people in Natalie's house than yesterday?
7:16 Paul Mecurio? Yeah, and they're like, there's like an old man and a baby.
7:19 Neil deGrasse Tyson? No, there's someone trying to crawl out of the basement. You know, that's.
7:23 Neil deGrasse Tyson? So how about, there's another point here. This is a little bit inside baseball. But Natalie, that's an expression we use here in America when you're about to give detail that probably no one cares about.
7:34 Natalie Starkey? Oh, okay.
7:35 Neil deGrasse Tyson? Because there's a TV show called Inside Baseball, and you really have to be into baseball.
7:39 Paul Mecurio? Right.
7:39 Neil deGrasse Tyson? To like, just to watch it or come near it at all. So this is an inside baseball question. As I remember my biology, life on Earth has a handedness to it. Not that you're right-handed or left-handed, but the molecules twist in a way that they could twist the other way, but they don't. And if they did, we couldn't use it in our life forms anyway. So on these rocks or in the stardust, the comet dust, do you have both? Do you have half twisting left and half twisting right?
8:10 Natalie Starkey? So this is the chirality, isn't it?
8:12 Neil deGrasse Tyson? Chiral, that's the word.
8:13 Natalie Starkey? Yeah. And you know what? This is so bad, but I can't remember what they found. But so basically, if you found the, are we left, aren't we, on Earth?
8:23 Neil deGrasse Tyson? I forgot. Here's my definite answer, why the left or right chirality, I'm sure of it.
8:30 Natalie Starkey? I can't remember, and I don't know whether it's really important that, you know, if we had the other handedness, whether we couldn't have a parallel life in that handedness or not. But I honestly, I just can't, my brain has gone blank not having looked at this.
8:43 Neil deGrasse Tyson? It's my understanding that we could, but we just don't, it's just an observed fact.
8:48 Natalie Starkey? Yeah, that everything is in one way.
8:50 Neil deGrasse Tyson? And my understanding, Paul, do you remember that, was it a potato chip or something that Frito-Lay made where it had all the oil of any normal chips, but you couldn't digest it? Because I think the molecule had a different chirality to it.
9:07 Paul Mecurio? It went through you, yes.
9:09 Neil deGrasse Tyson? It went through you, and the warning on the back of the package said, "May cause anal leakage."
9:16 Paul Mecurio? Exactly.
9:18 Neil deGrasse Tyson? Because your body has no idea what to do with it, even though it's oil, right?
9:22 Paul Mecurio? Well, thank God we're talking about something I know now, anal leakage. So let me tell you, when I was a young lad.
9:30 Neil deGrasse Tyson? So I think, I think there's a whole fascinating sci-fi story waiting to be written about whether you have left-handed or right-handed chirality in a life form. Because that means you couldn't eat, you could eat them, but it wouldn't be nourishing to you.
9:43 Natalie Starkey? Right, okay, so you could find lettuce somewhere, but you'd be like, this is lettuce, it's no good to me. But yeah, no, I think that's another issue we have, that we would need to develop experiments put out in space to actually be able to measure that. So it's one step actually measuring whether you have amino acids, and then it's another step figuring out more information about them. So, and we're sort of in the first steps when we're going out to look at planets and things.
10:06 Neil deGrasse Tyson? And I have a fast chirality story, I'm pretty sure this is true. That the molecular form of the flavor for mint.
10:16 Neil deGrasse Tyson? Okay, I think it's spearmint. Is the molecular form is identical to caraway. Except caraway has the opposite handedness. And so when it intersects your taste buds, your taste buds respond differently because of the different handedness of them. So mint and caraway are chemically identical. That's very cool. Really cool.
10:40 Paul Mecurio? Yeah.
10:40 Neil deGrasse Tyson? Well, let's get to some Q and A. So Paul.
10:42 Paul Mecurio? Yes.
10:43 Neil deGrasse Tyson? What do you have for us? Did you collect these?
10:45 Paul Mecurio? Uh, I collected them myself. I went through them and there's some really great questions. And, and we're going to start with Christopher Stowe in Pennsylvania. Is there a relationship between active geology, volcanism and a planet or moon having a magnetic field?
11:00 Natalie Starkey? Oh, yeah, that's a great question. So, um, generally we think yes. Okay, so we think that a body has to be active and activity means that you need to have heat within that body. And that can create basically liquid. So we, we need a hot rocky core usually. And that could create a liquid ocean underneath an icy crust like we see through many moons throughout the solar system. And we need that kind of activity and the movement of material. It doesn't have to be rock and water. It can be other elements. And, and we think that needs to actually be there to create a magnetic field. So we have seen magnetic fields all throughout the solar system, but they're not that common. They're common on like some of the bigger planets. And, and I think just a couple of moons, we've detected these kind of magnetic fields. But, but yeah.
11:44 Neil deGrasse Tyson? You can't just have a liquid, I mean, it has to be, uh, it has to be conductive, right?
11:49 Natalie Starkey? Yes, so a salty, a salty water can definitely do that. Um, a salty ocean.
11:55 Neil deGrasse Tyson? So you're saying it's not just that you have, it's not just that the place is hot. Is that there's a difference in temperature between places within the object so that things convect and move?
12:06 Natalie Starkey? Yeah.
12:06 Neil deGrasse Tyson? Yeah.
12:07 Natalie Starkey? Yeah, so it's not necessarily boiling hot. It's just warm enough that you've insulated a crust and, and then you can keep something warm enough that it's liquid and it can move so there's heat below and, and things move around.
12:18 Neil deGrasse Tyson? Got it, got it, okay.
12:19 Paul Mecurio? And when it comes to cryovolcanism, doesn't it have to be a mantle below this? There has to be, so in other words, for that liquid to be able to not freeze so that even though you're on a super cold atmosphere.
12:33 Neil deGrasse Tyson? Listen to Paul showing off he knows the word cryovolcanism.
12:36 Natalie Starkey? I know, you just got that in there, didn't you?
12:39 Paul Mecurio? I looked, I looked up one word and I repeated it like a hundred times.
12:43 Natalie Starkey? You sound so knowledgeable.
12:44 Neil deGrasse Tyson? My man does his homework. Man, okay.
12:48 Natalie Starkey? Yeah, so cryovolcanism, generally it's happening in places that are icy because we're talking about cryo being the ice part and the volcanism is the movement of that material. So usually underneath an icy crust, you've got a rocky core in the middle which is warm and then this kind of salty liquid ocean and it's from there that you're pushing material out. So it's that, that mantle as you call it, on Earth, our mantle is made of rock and it's below a rocky crust, but in, on these kind of icy moons, the mantle is made of, of water or methane or ammonia or some other solvent and that becomes your mantle, but it's just made of something different.
13:20 Neil deGrasse Tyson? I'd like that analogy because it's, you're analogizing basically the physics of what it's doing rather than the, the properties of the material itself. That's very, I'd love that.
13:30 Paul Mecurio? And then there was the pulls of the moons that allow the movement of that subterranean water so that it's not, get, doesn't turn to solid as well, right?
13:39 Natalie Starkey? Yeah.
13:40 Paul Mecurio? There's a sort of movement that happens?
13:41 Natalie Starkey? That happens in moons around these giant planets like Jupiter and Saturn. They are actually, they wouldn't just be hot if they were not next to that big planet. They need to be pulled by the gravity of that planet as they go about their orbit and it's that rocky interior that's pulled and pushed and squeezed and the rock is grinding all against other bits of rock and it, by friction heats up and then it creates that heat that makes that mantle liquid and then produces that activity. So, you know, if, if Io for example wasn't next to Jupiter, it wouldn't be the most volcanically active object in the solar system.
14:12 Neil deGrasse Tyson? But I think what Paul was referencing was if it was, if it was only Io and only Jupiter, then it would stabilize into just a tidally locked orbit and then there'd be no heat drivers. But we have other tugging forces that like you said, there's, it's a, it's a, it's a push and a pull and a tug and a, everybody's trying to get a piece of the action.
14:32 Natalie Starkey? Yeah.
14:33 Neil deGrasse Tyson? And response to that is a deposition of heat.
14:35 Natalie Starkey? Yeah.
14:36 Neil deGrasse Tyson? Yeah. Yeah. All right, Paul, give me one more before our break. See if we can squeeze it in.
14:40 Paul Mecurio? This is Connor Holm. Firstly, I loved Fire and Ice. You really make geology exciting.
14:46 Natalie Starkey? Oh, that's so good.
14:47 Neil deGrasse Tyson? I like the way that sounds. It's like, we know it's not exciting. We need it now.
14:52 Natalie Starkey? Well, that is one of the problems. People think geology is really boring. And then they look back and they're like, oh.
14:56 Neil deGrasse Tyson? No, Natalie, that is the highest compliment I've ever heard.
14:58 Paul Mecurio? Yeah, absolutely.
15:01 Paul Mecurio? In a typical volcano, how how high is the pressure buildup? And how is it measured? Does this vary between Earth and space volcanoes?
15:09 Natalie Starkey? Oh, that's a good one.
15:10 Neil deGrasse Tyson? I like that, but let's take a quick break. So we're going to take a quick break. When we come back, more with our solar system expert Natalie Starkey. When StarTalk returns.
15:34 Speaker 03 Hi, I'm Chris Cohen from Hallworth, New Jersey, and I support StarTalk on Patreon. Please enjoy this episode of StarTalk Radio with your and my favorite personal astrophysicist, Neil deGrasse Tyson.
15:56 Neil deGrasse Tyson? We're back. This is StarTalk Cosmic Queries. My co-host, Paul Mecurio. Paul, always good to have you, man.
16:03 Paul Mecurio? Thanks. Great time.
16:04 Neil deGrasse Tyson? All right. And friend of StarTalk, solar system expert Natalie Starkey, coming in from the UK. Natalie, great to see you again.
16:12 Natalie Starkey? Yeah, good to be back.
16:13 Neil deGrasse Tyson? Always good to have you. Very good to have you.
16:15 Natalie Starkey? Thank you.
16:15 Neil deGrasse Tyson? Paul, we dangled a question there, something about what's the difference in the pressures between like Earth volcanoes and space volcanoes? And that's an interesting fact, and how is it measured? So Natalie, how should we think about? The undercrust pressures that ultimately just blow a gasket.
16:35 Natalie Starkey? Yeah, so actually, it's really dependent on the volcano you're looking at, even on Earth. You get loads of different conditions. So you've got some volcanoes that will erupt at lower pressures and some that erupt at higher pressures. So generally, what we're looking at is the amount of gas that's contained within the magma. And if you go to, for example, let's take Mountains and Islands. Everyone's heard of that big volcanic eruption that exploded half the national forest. And that had a lot of gas in the eruption and it was therefore at higher pressure. If you go to somewhere like Hawaii, you're looking at Kilauea, that's at lower pressure. It's got less dissolved gas within the magma. What happens is as that magma rises with all those dissolved gases, they start to expand as just the pressure of the crust decreases
17:17 Natalie Starkey? and that magma gets thrown apart, basically. So that's what would create a very explosive eruption. But you've always got dissolved gases. So even in Kilauea, where it's not very explosive, you're going to get quite high pressures. So it varies a lot. Now, when we go into space, you're basically then it's very dependent on the individual place that you've got. If you've got a smaller body or a big, large planet, we tend to only see activity on the smaller bodies. So we've seen them on Mars. And we've seen quite big volcanoes on Mars and we've got loads of volcanoes on Venus, which are actually still active today. We've recently discovered that there's still activity today there.
17:55 Neil deGrasse Tyson? Whereas the ones on Mars are dormant, obviously, or dead.
17:58 Natalie Starkey? Yeah. Yeah. Yeah, so we haven't seen activity on Mars for, you know, quite a while now, billions of years, I think. Um, it's possible that it could one day have another eruption. It's very, very unlikely, but Venus, on the other hand, is continually erupting. So it's really, really active, probably much more active than Earth. And those individual volcanoes, again, are going to be all at different pressures and it will just be at a point when it'll erupt. But they'll probably be more similar to what we see in Hawaii, those volcanoes.
18:28 Neil deGrasse Tyson? Okay, so I have a task for Paul. Paul, I want you to invent, you know how we tap a keg? Or we should tap, figure out a way to tap a volcano. So we can release the pressure so then it doesn't blow its head, okay?
18:42 Paul Mecurio? Okay.
18:43 Neil deGrasse Tyson? And, and, and, and level cities that are at their base.
18:46 Natalie Starkey? And that's the thing like with supervolcanoes, you know, if they can release a little bit of pressure along the way with a little eruption, then it takes the, the pressure off that big one happening. So when they say, oh, there's a Yellowstone eruption due, it's due, but you know, it has little eruptions and releases bits of pressure along the way. So it just kind of extends that timeline to when that big one's gonna happen. Maybe that big one never happens because it just along the way releases a bit of pressure.
19:09 Neil deGrasse Tyson? We should purposely dig holes and let it break.
19:11 Paul Mecurio? I was gonna say, I have a, I, listen, I have a new DeWalt cordless drill. I can just,
19:16 Neil deGrasse Tyson? That'll do it.
19:17 Paul Mecurio? Just drop me right in and then, hey, let me ask you something. How much greater is the pressure than the baking soda volcano I made in fourth grade? Cause that sucker spewed everywhere and I gotta tell you, it ruined my mother's drapes. I was grounded for a week, literally.
19:33 Natalie Starkey? I can't believe you did that indoors. I did it outside in the garden on the grass and it killed the grass and I was in loads of trouble as well. So, yeah.
19:42 Paul Mecurio? A quick, quick question in all seriousness, is there a common reason is when volcanoes go dormant in space? Is there a common, is research showing a common reason for that or does it vary depending on the celestial body and other factors or?
19:58 Neil deGrasse Tyson? Wait, wait, Paul, are you a Patreon member?
20:02 Paul Mecurio? Hang on a second. I got five dollars somewhere.
20:05 Neil deGrasse Tyson? You got five dollars, go find the five dollars.
20:06 Paul Mecurio? All right, we'll go, we'll ask the next question.
20:08 Neil deGrasse Tyson? Put it in the piggy bank.
20:09 Paul Mecurio? All right, sounds good. All right. Next question, are we moving on?
20:14 Neil deGrasse Tyson? Yeah, no, you can ask your question, Paul, I think.
20:17 Paul Mecurio? No, you ruined it.
20:18 Neil deGrasse Tyson? I ruined the moment, okay.
20:20 Paul Mecurio? No, no, no, go ahead.
20:21 Natalie Starkey? I think it's a good question. So basically in order for a, a body to be active in space, it's got to be warm. We took, we spoke about that in the last segment. And we were talking about how we've got to have heat within a body to create activity, create movement of material within that body, whether it be rock or methane or water, whatever it is that becomes that, that magma and lava on that, of that particular body. So if that particular object cools down and it loses its heat for some reason, it just primordial heat, a lot of bodies were just active because they had heat from formation because they formed from big kinetic impacts in space and that created heat. And they just lose that over time and they die. They do all the volcanic activity dies off and they can no longer be active because they're not warm enough.
21:06 Natalie Starkey? But then we go somewhere like Jupiter where we've got this push and pull of the gravitational energy. Those bodies can be active for forever, really, because if they stay where they are and Jupiter keeps going around the sun, then they're going to keep being active. So there's really no, no time limit on that.
21:21 Paul Mecurio? Got it. Okay.
21:22 Neil deGrasse Tyson? So that's, so can we say that Mars has just simply cooled off?
21:27 Natalie Starkey? Yeah.
21:27 Neil deGrasse Tyson? From its formation and so and it's smaller than Earth, it would cool faster. And so now it's got no action left.
21:33 Natalie Starkey? Exactly. And the same with the moon, it's even smaller. So it's just cooled off quicker. So Earth is sort of this, this really nice example. It's not too big that it became ridiculously sized like Jupiter or something and, and it's just not even a rocky planet any longer. It's just big enough to, to have kept its primordial heat and it also generates its own heat. So it's kind of that really nice sweet spot of being able to be active, but not be too active. It's not too hot and it's not too cold. So it's kind of, you know, the perfect planet, I think, anyway. I think it's a nice place to be.
22:02 Neil deGrasse Tyson? Says, says the geologist, we're in a sweet spot that gives us volcanoes, earthquakes and tsunamis. Yes, thank you, Natalie, for calling that a sweet spot.
22:10 Paul Mecurio? Right, right. Imagine being at her house, hey, there's going to be a hurricane this weekend. I can't wait.
22:16 Neil deGrasse Tyson? That's a sweet spot.
22:17 Paul Mecurio? The sweet spot. Okay.
22:20 Neil deGrasse Tyson? All right. What else you got, Paul?
22:21 Paul Mecurio? Moving on. Yep, we got Troy from Virginia. What are the current processes of detecting life outside of Earth? Would it be detecting radiation around an area that could contain food for different life forms or is it something else?
22:36 Natalie Starkey? Oh, that's really cool. I love this topic. So one of the ways that we first go out into the solar system to look for life is not to look for life itself. It's to look for the environments that could host life. So we wanna look for habitable environments. Now, we think that includes liquid water, because we think from what we know about Earth, all the environments we find life and where we think life started, included liquid water and heat. So we go out to all these places, and this is why we're sending the Juice mission, which launched just recently. It's looking at some moons around Jupiter that have those environments. They've got warm interiors, they've got liquid water, and these create what we call hydrothermal systems, which is what exists
23:18 Natalie Starkey? at the bottom of our oceans. And we think life actually started on Earth, potentially, at the bottom of our oceans, and where the heat is emanating from the Earth, and it's interacting with salty liquid water, and it's creating nice environments for microbes to thrive. So that's where we're going. We're going to look for these environments. And then, we're going to go, okay, do these places host the right ingredients for life? And then, we will look for life. Because there's no point looking for life. It's really hard to see life. Because if it's microbial, for example, we're not going to be able to see that from orbit. We're gonna have to land on that planet, we're gonna have to drill in, we're gonna have to delve into an ocean to actually see microbes.
23:54 Neil deGrasse Tyson? Drill, baby, drill. That's what we do.
23:56 Natalie Starkey? Wow, I know. Find out a submersible. You know, that's complicated. Of course, if there's dinosaurs roving on these places, we'd see that from orbit, fine. But we don't expect to have dinosaurs roaming around. So, we're looking for very probably small life, or it might have been life that doesn't, it's now died off. So we'd be looking for fossilized microbes, which is incredibly hard to find. So, initially, we're just gonna look for environments, like we've been doing on Mars, we're looking for those kind of, you know, saline, watery environments that might have hosted life in the past. And that's the best place to start.
24:27 Neil deGrasse Tyson? You don't expect to see fossilized microbes, because they don't have like, bones and teeth, right?
24:31 Natalie Starkey? Yeah.
24:32 Neil deGrasse Tyson? It's a speck of dust. Right.
24:35 Natalie Starkey? In the geological record, we have seen examples of where sometimes, you know, stuff without, or bones, everything has been preserved. But it's incredibly, it's really uncommon. You've got to have perfect conditions of deposition to kind of cover that stuff over and preserve it perfectly in that record. So-
24:51 Neil deGrasse Tyson? So it's not, so it's not destroyed over time, right?
24:53 Natalie Starkey? Yeah, exactly. I mean, you would need to be on the surface of a planet to find that. And you'd probably want humans there to be looking. Robots and, you know, they're gonna go and do a good job. But you need, you know, humans and, and the our superior intelligence to help find these things.
25:07 Neil deGrasse Tyson? Until AI becomes our overlords, then they're our security.
25:11 Paul Mecurio? Which is about a week away. Why don't we just?
25:14 Neil deGrasse Tyson? Next week, is it next week? You know something, Paul?
25:17 Paul Mecurio? It's happening. That's what I was told by my AI. Why don't we just set out some like, like alien bait? Like a full spectrum radiation banquet? Like, it's almost like a, like a banquet on a carnival cruise where just people eat so much. They fall asleep in their chair. So the aliens come, they eat the radiation banquet, they fall asleep and then we trap them. And then we study them.
25:38 Natalie Starkey? I mean, we, we do send radio signals out into space. So this is assuming that aliens can detect our radio signals and understand what we're saying. But we, we have been doing that and we've sent messages out on spacecraft over time. You know, to go out there and to say, look, we're here. I don't know, you know, I'm not sure if that's a good idea because we don't know if these aliens are friendly or not, you know?
25:57 Neil deGrasse Tyson? In retro, in retrospect, that feels a little dangerous, but yeah.
26:01 Natalie Starkey? Yeah. But yeah, we do that. And, and you know, another way, so when we're talking about the solar system, it's one thing. Cause we can get to these environments, we can send spacecraft and investigate them. But you then get to the exoplanets. So these are all the, the, the objects around other stars and other star systems. So far away, we can't directly see them. So we're using a different type of science then to try and detect what might be going on. Initially, we're just looking for whether the planet is hot or cold. And how close it is to its, its star. And because if it's too far away, we don't think it would be able to host life. Is it too close, it'll be too hot? So we're looking for things that are kind of within a zone that might be able to host liquid water or definitely have activity. But that's like the next step.
26:42 Neil deGrasse Tyson? A Goldilocks zone.
26:43 Natalie Starkey? And the Goldilocks zone is sort of being a little bit disproven more recently. Because we're starting to now in our solar system, see environments, you know, way, way like Pluto, for example. Not in the Goldilocks zone, but it's theologically active. And, you know, there is every chance that life could have started there. And because it's got all kind of the right conditions for, you know, very weird life to exist, but it could be there.
27:07 Neil deGrasse Tyson? A new species of dog, yeah.
27:09 Natalie Starkey? Yeah, who knows? There's labradoodles all over.
27:12 Neil deGrasse Tyson? Labradoodles.
27:14 Paul Mecurio? It's a species of dog that cleans up after itself. Please, God, please.
27:19 Neil deGrasse Tyson? So Natalie, you mentioned, you just slipped by, you mentioned it, we did an entire explainer on it, but just for those, this might be their first time hearing, use the word a juice mission. Could you just?
27:30 Natalie Starkey? Oh, yeah.
27:30 Neil deGrasse Tyson? Spend a minute, just a minute on that before we go to the next question.
27:33 Natalie Starkey? Yeah, so the juice mission just launched recently. It's a European Space Agency mission. And, okay, so the acronym is really forced. It's Jupiter, IC, Moons Explorer. So you kind of have to think through that one for how they got juice out of it. But it does work in some way. All the letters are there, within those words, anyway.
27:50 Neil deGrasse Tyson? Yeah, J U Jupiter, and I C Ice, and E Explorer. That's not too forced.
27:54 Natalie Starkey? Yeah, okay.
27:55 Neil deGrasse Tyson? We'll give them that one. We'll give them a B plus on that one.
27:57 Natalie Starkey? But yeah, it's not going to be arriving at the Jupiter system until 2031. So I think, you know, this is one of these crazy things about space missions. They set out and then it takes forever to get anywhere in space. And it's got to do some slingshots of Earth and gain gravitational energy to get out to Jupiter. But it's then going to be looking at Europa, Ganymede, and Callisto, which are three of Jupiter's moons. And actually, NASA are going to launch, hopefully launch, the Europa Clipper mission next year, I believe, which is actually going to then get-
28:27 Neil deGrasse Tyson? That's my understanding, next year.
28:28 Natalie Starkey? It's getting there ahead of Juice, which is a bit cheeky. It's like going to arrive a year ahead, even though it launches later.
28:34 Paul Mecurio? Natalie, everything's not a competition.
28:37 Natalie Starkey? Yeah, I think, you know.
28:38 Paul Mecurio? We're, we're sorry about 1776. You gotta let it go. Let it go.
28:44 Neil deGrasse Tyson? Drop it.
28:44 Paul Mecurio? Oh my God, with, I'm sorry.
28:47 Neil deGrasse Tyson? Just to clarify, if you do not launch with sufficient energy to go straight there, then you need the gravity assists through some, you know, multi-cushion pool shot in the solar system. So it sounds from what you said, that our Clipper mission from NASA will be on a larger rocket and it'll be able to go straight there and not have to rely on gravity assists, which eats time in the duration to the destination.
29:14 Natalie Starkey? Exactly. So yeah, it just, and it's also with the, you know, orbital dynamics, it depends where the planets are, when everything launches, and then, you know, how far it is going to be to get to places and whether you can go in a straight line.
29:25 Paul Mecurio? Is the focus of the, what, I would imagine the focus of the two missions is different, right?
29:30 Natalie Starkey? Um, it's really, really similar, which is really cool because they'll be complementary. So Europa Clipper is only looking at Europa, um, but it's investigating the signs for life. And then the JUICE mission is looking at all of those moons, investigating what their surfaces, what the composition is, getting more information in detail, just imaging surfaces. We haven't got hugely detailed images of these places. And then measuring things like particles that are coming off of the surfaces, discovering, you know, what's underneath in their liquid oceans, because they all have liquid oceans. They all, I think they all have more liquid water than we do have on Earth.
30:04 Neil deGrasse Tyson? That's, that's my understanding. That's correct. The total liquid content versus our oceans, right? It's, I think they have more.
30:11 Paul Mecurio? Is it Iowa that had, Io has a hundred mile deep ocean or something like, is it?
30:16 Natalie Starkey? That's probably Europa. Io is the really hot one. So that's the weird one. All the others are icy there. But yeah, so they've got huge oceans. Um, I think it might be Ganymede that's the biggest one. And it's actually bigger than Mercury.
30:28 Neil deGrasse Tyson? Yeah, yeah, Ganymede, right, that's right.
30:30 Natalie Starkey? It's a crazy big moon.
30:30 Paul Mecurio? I understand that James Cameron's going to Europa to see if there's anything that's at the bottom of the ocean that he can somehow make a movie out of. So that should be really good.
30:39 Natalie Starkey? I'd watch it.
30:40 Neil deGrasse Tyson? But I, I'd want to start a movement. Any life forms we find on Europa, we should call them Europeans.
30:47 Paul Mecurio? There you go. That's perfect.
30:49 Neil deGrasse Tyson? That's how we gotta do that. Well, we have an explainer on that, um, where if one of people want to do a deep dive on it, you can look it up on our website. So Paul, give me one more before our break.
30:58 Paul Mecurio? You got it right here. This is Ian Diaz from North Florida. Is it possible to get energy from a planet's core? And if it isn't possible, how could we hypothetically achieve energy from a planet's core?
31:11 Neil deGrasse Tyson? I love that. And let's, let's do take that break. When we come back, we're going to find out what is the future of geoengineering? And how much energy does Earth have to give? Especially relative to other sources such as oil, or perhaps even the sun, when StarTalk continues.
31:49 Neil deGrasse Tyson? We're back for the third and final segment of Cosmic Queries StarTalk. I got Paul McCurial with me as my co-host and Natalie Starkey. Natalie has two books under her belt. We've done shows on each of those two books. You can dig them out of our archives. One of them is called Catching Stardust: The Study of Particles Brought Back to Earth From Space and Just Dust Everywhere Where It Matters When We Think About Life. And my favorite of those two, sorry to pick one of your children here, Natalie.
32:20 Natalie Starkey? It's not loud.
32:21 Neil deGrasse Tyson? Fire and Ice, it's got a way cooler title, I think.
32:24 Paul Mecurio? I was gonna say, can I just say, we need to make that a musical. Fire and Ice the Musical.
32:31 Paul Mecurio? And then we have a volcano and Neil, like with Nathan Lane, he comes singing and dancing out of the volcano.
32:37 Neil deGrasse Tyson? Oh, you need Nathan Lane if it's gonna be one of these.
32:41 Neil deGrasse Tyson? And Fire and Ice is, will be coming out in paperback soon. Because that's the more recent of the two books. We look forward to that. And Paul, at the top, I forgot to tell people, you're a comedian on The Late Show with Stephen Colbert.
32:54 Paul Mecurio? I am.
32:55 Neil deGrasse Tyson? Do you help write his jokes?
32:57 Paul Mecurio? I basically perform on the show. He and I go back to The Daily Show together. I was a writer on The Daily Show, I worked on The Colbert Report, and I do a mix of things on The Late Show.
33:06 Neil deGrasse Tyson? I think that's when we first met, when I was a guest.
33:08 Paul Mecurio? That's where we met.
33:09 Neil deGrasse Tyson? Yeah, guest on The Colbert Report.
33:11 Paul Mecurio? I didn't know you were in the green room and I came in and tried to steal some of your snacks and you caught me.
33:16 Neil deGrasse Tyson? That's not gonna happen, yeah.
33:18 Paul Mecurio? And yeah, and I have a podcast called Inside Out, which you've been on, and Paul McCartney, and Stephen Colbert, and a whole bunch of cool people, so yeah.
33:24 Neil deGrasse Tyson? Okay, so just to be clear, the title of your podcast is Inside Out with Paul McCurial?
33:30 Paul Mecurio? Yes, it is, yeah. Yeah, I should, I should put my own name in there, probably would help, right?
33:34 Neil deGrasse Tyson? That's what it is, okay. You got it. All right, so let's pick up where we left off.
33:39 Paul Mecurio? Okay.
33:39 Neil deGrasse Tyson? We dangled a question, and please remind us of what that question was.
33:44 Paul Mecurio? Is it possible to get energy from a planet's core? And if it's not, how could we hypothetically do that?
33:49 Neil deGrasse Tyson? Plus, Natalie, if the core is really, really hot, then there are surely places between the surface and the core that are not as hot, where you don't have to dig as deep, and you could, in principle, still get energy from it, isn't that right?
34:02 Natalie Starkey? Yeah, so, I mean, the core of the planet is incredibly hot. I think it might be hotter than the surface of the sun. Most of this heat in our core is a leftover from four and a half billion years ago when the planet formed. You've got all those impacts happening in space that built up the planets. And that kinetic energy was turned into heat, which was stored within that metal core. Okay, so you've got a lot of what we call primordial heat in there. But then you've got this mantle of rock that sits around that. And actually, that generates heat all the time because we've got lots of radioactive elements sitting within the rock that decay over time and release little bits of heat, which when you've got a huge amount of rock that does that, creates a huge amount of heat for our planet. So we've got that initial heat and then we've got the heat we're always making. And that's about 50 50 in terms of the heat that our planet gives out. Now,
34:46 Natalie Starkey? because of physics, heat always wants to move from somewhere hot to somewhere cold, which is space. So it moves from the inside out and it keeps our planet active. It creates volcanoes and earthquakes. But it also gives us our liquid water and it can create energy for us. So, you know, if we go to somewhere like Iceland, they actually just use all their electricity comes from geothermal energy. And they actually heat their roads using just the heat from the earth, because it's very, very cold in Iceland and they have very icy roads. So they just, they just heat them because they've got all this excess energy, which they don't have to generate.
35:19 Neil deGrasse Tyson? That's the most badass thing I've ever read about. So they don't have snow shovels or they don't have to salt the road. They just.
35:26 Natalie Starkey? Well, they do in some places, but in particularly in Reykjavik, because it's quite, you know, it's not a huge population in Iceland, but a lot of people do live in the capital city. And, you know, they can just do that. They have all this excess heat. So they can just heat it.
35:39 Neil deGrasse Tyson? They're just, they're just show offs there. They're just showing off. No, but an interesting point is that they used to be run on fossil fuels and they just made a determined effort for this shift. It's one of the more brilliant, sort of scientifically literate energy stories in the world.
35:54 Natalie Starkey? Yeah, and they can do that because they, they're a volcanically active place. They sit on the mid Atlantic ridge, but they also have a hotspot underneath Iceland, which is just this kind of warmer area of the mantle that produces excess heat and excess volcanoes. You've got the same in Hawaii. It's a hotspot volcano. But you don't need to be near a plate boundary where you create volcanoes or near a hotspot to necessarily create. You're thermal energy. You actually just need to drill down, not even very deep. If you drill down a kilometer, you get a twenty five degree increase in temperatures. Now, you don't even need that much increase to generate a little bit of heat. I don't know in the US if you have like air source heat pumps for your houses. We have, they're quite common here now.
36:34 Neil deGrasse Tyson? We don't even know what that is. I've never heard of it.
36:38 Paul Mecurio? I have one. I actually have one. I just.
36:40 Neil deGrasse Tyson? You, you are lying.
36:41 Paul Mecurio? No, I, I will show you a picture right now. It works at thirty, listen to me. I know something about science here. Focus. At thirty, at thirty five degrees or above, this is a heat pump. So I don't use so much oil in my furnace and it's thirty five degrees or above. There's enough moisture in the air. It's a reverse process. So it's like, it's an air conditioning condenser that reverses its process. It takes from the cold, the moisture goes through and it turns it into heat. I am done. I finally said something that I know what I'm talking about.
37:11 Neil deGrasse Tyson? All right, it's good.
37:12 Natalie Starkey? So you, yeah, you don't need a huge amount of heat.
37:14 Paul Mecurio? We've saved a ton of money in all seriousness on our house. We've saved a ton of money on oil with this.
37:19 Natalie Starkey? Yeah, it's becoming very common in the UK that we're, we're actually switching over to these and all new build houses. Anyway, that's kind of a tangent, but like basically we don't need a ton of heat to actually create enough to, to heat houses, heat hot water.
37:32 Neil deGrasse Tyson? In other words, you don't need to dig to the core of a planet.
37:34 Natalie Starkey? Yeah.
37:34 Neil deGrasse Tyson? To gain access to the energy that remains within the planet itself.
37:38 Natalie Starkey? Yeah, exactly. So we, yeah, and we need to do that more. And, you know, if we want to do that, it is environmentally, we've got to question it a little bit because we've got to dig into our planet and we've got to lay pipes. But, you know, then we wouldn't require fossil fuels, which would be great. But, yeah, it's just one form of renewable energy, which we're not really using, but Iceland have done it great. I think areas of New Zealand do it because they have a nice, high heat flow as well. And, but yeah, definitely we, we take heat from our planet all the time.
38:02 Neil deGrasse Tyson? Very cool.
38:03 Paul Mecurio? Why don't we harness the energy that we expect to get to the center of a salted caramel core pint of Ben & Jerry's ice cream? You're working toward that core, you can really harness that energy.
38:15 Neil deGrasse Tyson? We'll get top people working on that.
38:17 Paul Mecurio? Another question? All right, drilling, this is from William. Drilling down to Lake Vostok in Antarctica has been cited as an analog for exploring ice moons like Europa. Can you tell us what was learned from Vostok?
38:32 Neil deGrasse Tyson? I love that. So what is Lake Vostok, Natalie?
38:34 Natalie Starkey? So the really cool thing about these environments on Earth like Lake Vostok and there's some other areas in Antarctica we can look at is that you've got these bodies of water that have remained sort of pristine since they formed, so they've been capped off with ice. And you've got this water that's just stayed there the same and hasn't had any human interactions in all the years it's been there. And this is very similar to, you know, the places we look at like Europa or Ganymede or anywhere else where we've got these liquid oceans with this ice capping it.
39:02 Neil deGrasse Tyson? Not only just not, no human interaction, nothing has reached it, right? No other part of the biosphere has touched it, right? So these have been like, so if something's gonna happen, it's all up to itself, right?
39:13 Natalie Starkey? Exactly.
39:14 Paul Mecurio? Isn't it like six, isn't it like 16 million years ago it was believed to have been sealed off, like that long ago or even longer?
39:21 Neil deGrasse Tyson? Certainly on an evolutionary timescale. I don't remember exactly how, how long these have been capped off. But that's the, just the only point of this is it's, it's like an analog, right? Is that what you say?
39:31 Natalie Starkey? Yeah, so we need analogs because it's incredibly hard to go out and actually investigate these places in space. And we spoke about that already in this episode. You know, it's, we gotta send spacecraft, it's expensive, it takes years to get these missions out there and plan them. So actually, if we can look at a similar environment on our own planet and compare it with those environments we think exist in space, then we can do a lot of the work before we even have to go out there and investigate what's there. So they become like a little comparative and planetology experiment and, and it just gives scientists a really easy way to do their work, although it's still relatively hard to get to Antarctica. But we can actually do that science before we go to Europa and we can make all the mistakes here and then figure out what we need to do in space with a very limited equipment.
40:15 Neil deGrasse Tyson? Have they found weird life forms? Do we know, what do we know?
40:18 Natalie Starkey? So what we know about, so we find lots of strange environments. On Earth, some of the strangest environments are at the bottom of our oceans, where you find organisms living that just shouldn't be able to survive. There's no light, it's incredibly dark and high pressures, very cold. And these kind of environments are where we find microbes that we call extremophiles. They like extreme environments. So humans and other animals that we see on the surface of the Earth couldn't survive down there. But there are organisms that have adapted to those environments and thrive. There's a whole, you know, a whole colony of animals and bugs and things down there, which we just weren't expecting to find.
40:56 Neil deGrasse Tyson? So gone is this Darwinian concept of the room temperature tide pool.
41:01 Natalie Starkey? Yeah.
41:01 Neil deGrasse Tyson? Where that's where you need the like, I mean, it blows it right open, blows it completely open.
41:07 Natalie Starkey? Yeah, in fact, life probably, we think, most likely started in one of these very extreme environments. And so we've kind of developed to now think that we live in a very, you know, we can't stand extreme temperatures. Humans are a bit rubbish in that respect, but actually.
41:21 Neil deGrasse Tyson? So Paul, did you just call us wimp ass creatures?
41:25 Paul Mecurio? I think she did.
41:25 Neil deGrasse Tyson? I think she did, I think she did.
41:27 Paul Mecurio? You know, I did not shave for this. I don't, you know, I. Can I just ask, you talked about Lake Vosok being an analog, but isn't it limited in some ways because you can only extrapolate so much? Because the host bodies are different, right? Earth is a different celestial body than, say, Europa. So there's only so much you can glean.
41:45 Natalie Starkey? Yeah.
41:46 Paul Mecurio? From that analog.
41:47 Natalie Starkey? And that's like with any science we do, we have to start with a set of assumptions. And we always know there's going to be, you know, limits to the experiment. And that would be one of the limits. It's not the same place. But it's pretty close. And in some respects, it's close enough that we can test out some of these theories before we go out into space.
42:05 Paul Mecurio? Hey, we don't do close enough in America. We do it right, or we don't do it at all.
42:13 Neil deGrasse Tyson? There you go.
42:14 Paul Mecurio? Do you want to go another one more question?
42:16 Neil deGrasse Tyson? We got time, a couple more, yeah.
42:17 Paul Mecurio? Alright, okay, this is Chase. Greetings, Dr. Tyson and Dr. Starkey. Chase from Indianapolis here. My question is, could you pump as much water in the ocean as is to be added per year by the melting ice and then put it in a rocket and ship it to Mars?
42:35 Neil deGrasse Tyson? Oh, so that we don't have, so that in the climate change, we don't flood the coastal cities?
42:41 Paul Mecurio? Thus saving coastal cities and accelerating Mars projects.
42:45 Neil deGrasse Tyson? Wow, because I bet the cost of picking up cities and moving them inland 50 miles is probably more than shipping water to Mars.
42:55 Paul Mecurio? Can we just over, we're overthinking it. Can we just get 500 million jugs of Poland Spring delivered to another planet? Probably get it in bulk, discount at Costco. You create, you brilliant scientists, you're always overthinking things.
43:07 Neil deGrasse Tyson? Yeah, that's true, that's true, just ship it all out. So, yeah, what, so, so, I don't know. So, was there a question in there?
43:13 Paul Mecurio? Yeah, my question, could you pump as much, could you pump as much water in the ocean as is to be added per year by the melting ice and then put it on a rocket and ship it to Mars?
43:24 Natalie Starkey? So, I think the first part of that question, I have no idea. But the second part is going to be the main issue, I think. I'm sure someone who pumps water might understand the first part a bit more, but the second part's going to be an issue anyway because to launch bulk into space is the most expensive thing. So this is why when we design space missions, we make everything very small and light. The instruments we send usually are not very large. You know, some of them are literally the size of a shoebox. Obviously, some spacecraft are much larger, but they're made to be light because it's just very expensive. The more rocket fuel you'll need to launch some mass into space, the more rocket fuel you'll need because you've got then more rocket fuel, and it just is exponential. So you want to keep everything light. So launching water into space is never going to be a good idea.
44:07 Natalie Starkey? We have to do it, but actually, we limit it. So on the International Space Station, they recycle their urine because they don't have an unlimited supply of water. If we go to the moon and Mars, like we're planning to send humans out and create bases out there, they're going to need to find ways to generate their own water, either from rocks on the surface of the planet and the dust, or from a passing comet or asteroid, we might mine it for water. That's actually going to be much more efficient than trying to launch the stuff off our own planet. So that is a massive problem.
44:37 Neil deGrasse Tyson? So, Paul, I think the answer is no.
44:38 Natalie Starkey? Yeah.
44:42 Paul Mecurio? Sorry Chase, that's a big no buddy.
44:44 Neil deGrasse Tyson? That's a total no. And last I heard, the cost to launch a pound of anything in a payload is somewhere between five and $10,000. So, the rate at which the ice is melting, per pound times $10,000, you know, that's just, it would be prohibitive. Yeah.
45:03 Paul Mecurio? So, let's do that calculation. What did it cost, uh, Bezos to launch William Shatner? Let's get the calculator out on that. Do we, uh, you want to do another question?
45:16 Neil deGrasse Tyson? Yeah, yeah, let's keep going.
45:17 Paul Mecurio? Okay, this is Kayla Hunter. "Hey guys, what would happen if a volcano erupted on the moon, where the gravity is at .16 G? Would the lava float in the air, or up and out into space?"
45:32 Neil deGrasse Tyson? Ooh.
45:33 Natalie Starkey? Really cool.
45:34 Neil deGrasse Tyson? So, let me sharpen that question. So, the thrust of ejections from volcanoes, might they be fast enough to achieve escape velocity for the moon? Or will it just be like a volcano in slow motion, where things go up and fall down slowly?
45:50 Natalie Starkey? So, yeah, it can definitely happen. Like, we see on Enceladus, its volcanoes throw out material in plumes, and some of that material ends up making Saturn's E-ring. So, one of the rings, I think it's the second one in, that goes around Saturn, the material for that ring comes from Enceladus's volcanoes.
46:08 Neil deGrasse Tyson? So, it did achieve escape velocity?
46:09 Natalie Starkey? It did, yeah. Now, on the moon, we've had loads of volcanoes, but about 3 billion years ago, they all sort of stopped. Now, we had, usually, they were quite basaltic in composition. So, this is the same kind of volcanoes as we get in Iceland and Hawaii. Very flowy, they're not very viscous, so they don't have a lot of energy to explode out, they just kind of flow over the surface in big valleys.
46:33 Neil deGrasse Tyson? Natalie, is that an official word, "flowy"?
46:35 Natalie Starkey? Flowy, flowy, I think so.
46:38 Paul Mecurio? That's the name of her labradoodle.
46:42 Neil deGrasse Tyson? The one she's breeding on the planet Pluto.
46:45 Paul Mecurio? Yeah, exactly. It's part of that whole creepy breeding process she has going on in her basement right now.
46:51 Neil deGrasse Tyson? In her basement, yeah, okay.
46:52 Natalie Starkey? With the microbes. Some of the eruptions on the moon were more explosive. Actually, towards the end of volcanism on the moon, stuff was less flowy, let's say, and actually became much more explosive. And we got fire fountains. So I don't know if you remember, there's been quite a few fire fountain eruptions on Earth in the last few years. La Palma had some, I think a couple of years ago. And this is where we just get explosive.
47:14 Neil deGrasse Tyson? La Palma, the Canary Islands?
47:16 Natalie Starkey? Yeah. So I don't know if you remember, it was all over the news, 2021, huge fire fountain eruptions. And that actually would have happened on the moon back in the day about three billion years ago. So, but again, the magma's too heavy, it's too dense in order to kind of escape the moon surface. But generally, it all just rained back down. So, yeah, in general, it won't be out floating around in space.
47:37 Paul Mecurio? Is it different for cryovolcanoes? Is it different for something that's sort of emitting sort of ice and?
47:43 Natalie Starkey? Yeah, definitely. So gases will definitely, you know, be able to escape much more easily because they're lighter. And it really depends on, it just depends on the individual body and how much gravity it has. But ultimately, it's going to be pretty hard for most stuff to escape unless it's very explosive, like we find on Enceladus or something.
47:59 Neil deGrasse Tyson? Well, plus, the moon has a stronger gravity anyway than probably many of those other moons. Our moon's one of the bigger moons in the whole solar system. We got a badass moon for how small Earth is, right?
48:10 Natalie Starkey? Yeah.
48:11 Paul Mecurio? Our moon can take your moon every day of the week.
48:15 Neil deGrasse Tyson? Meet me outside.
48:16 Paul Mecurio? We'll meet you, meet you in the parking lot behind the school, man.
48:21 Neil deGrasse Tyson? So I think that's all the time we have for questions, but I want to get some final reflection from you, Natalie. Much of what you described in the questions that related to life, it sounds like we're looking for life as we know it. And isn't in the end, wouldn't that be highly restrictive? Ken, is there a way to look for life as we don't know it?
48:40 Natalie Starkey? Well, the thing is, we still know that everything in the solar system and the universe has to adhere to the laws of physics and chemistry as we understand them. So it always doesn't make sense to start looking for life in some other elementary form that, you know, doesn't make any sense for the way that we understand science. But it doesn't mean that another solvent like methane or something couldn't actually host life. So we are looking not just at places that have liquid water, but for example Titan, which is a moon of Saturn, we're looking at that because it has water, but it's also got a methane cycle. So instead of a hydrological cycle, it's got rivers and rain of methane that comes and goes and it has clouds that form.
49:21 Natalie Starkey? So it's this active environment, but it isn't water necessarily that we think the life could be surviving on, but this is all organic based stuff.
49:29 Neil deGrasse Tyson? So I got it. So liquid water might be an unnecessary assumption. Maybe it's just liquid of some kind.
49:36 Natalie Starkey? Yes, you definitely need a liquid to be able to move things around. So, you know, organic material needs to be able to move and find other bits of organic material and to create, you know, the basic forms of life. So without liquid, you're going to really struggle. But even in a really icy environment, there's always going to be some liquid at like, you know, the edges of glaciers or whatever it might be. So there's always the potential, but we don't necessarily need water, we don't think, but we know that water works because we've seen it happen here. So that's where we're initially looking. But yeah, you know, there could be life based on other forms of things that we don't currently understand, but it doesn't make sense to go and look for that because we need to start with what we know and then work out from there because there's too many, you know, it would just be crazy to start looking for things.
50:21 Natalie Starkey? We might wouldn't know how to recognize it or detect it if it didn't look like stuff that we understand.
50:26 Neil deGrasse Tyson? Okay, so Paul, I think she's just trying to prevent people from investigating her basement.
50:30 Paul Mecurio? I think, I think that's clearly, I have felt, I have felt this entire show was just her just obfuscating and some rules.
50:40 Neil deGrasse Tyson? That's all the time we have. Natalie, it's been a delight to have you back. I forgot how much we missed you over COVID. And we're going to reach for you again because the solar system is a never-ending playground Exactly. of space probes and new hypotheses and the search for life. So thanks for being a guest once again on StarTalk. Thanks for having me. All right, Paul, we'll look for you on the Late Show. Yep, you'll see me there. There you go. All right. This has been another episode of StarTalk Cosmic Queries. Neil deGrasse Tyson here, as always. Keep looking up.
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