Cosmic Queries – Space Volcanoes: Fire and Ice with Natalie Starkey

Hey, Stark Talkins, Neil here. You're about to listen to an episode, especially drawn from our archives, to serve your cosmic curiosities. The archives run deep. If you enjoy this, take a peek at the full catalog on your favorite podcast platform. There's a lot there to tickle your geek underbelly. Check it out. Welcome to Stark Talk. Your place in the universe where science and pop culture collide. Stark Talk begins right now. This is Stark Talk. You'll be grasped ice in here. Your personal pastroom consists. We're going to do another cosmic queries addition. These are becoming so much the favorite of our listening and viewing audience. And today we're going to do fire and ice. I love it. It's literary and scientific and we'll get into it in just a moment. First my coast for this episode, Matt Kershian. Matt, welcome back. Hey, how's it going? Matt, I love it when comedians are into science. You've got your own podcast called probably science. I think I get it right. That is it. I did it last time and I got it right. Two in a row. I'm loving this. Yeah, the probably is in that for good reason. I would say I... Don't undersell what you got going there. That's true. I like being described as a comedian that's into science. I'm not a failed math student who fell back was into comedy. Even though that's exactly what happened there. That was exactly what happened. So it means you do have math fluency. That's always good. I can't... I did it one point. Yeah. Well, always good to have you back. And today, fire and ice. I love the literary reference that that makes just, you know, it just makes you wonder, you know, what's... Is it good? Is it bad? And we have someone who's like an expert on the fire and ice of the solar system. And that is Natalie Starkey. Natalie, welcome back. Hi, I'm Peter. First Star Talk rodeo. And not so nice. Yeah, that's excellent. You're coming to us from the UK. And let me get your official title. You're a public engagement officer at the Open University, which is an institution just outside of London. And you're a science communicator. That's just a beautiful thing. Because we need more of that. Can we clone you? You'll be the best in line. There's loads of us. There's so many of us out there. And it's amazing, you know, when I'm in this field. Yes, it's a... These are the practitioners. There's so many of us. We can call it a field, right? Yeah, exactly. A place to be. A place to be. You're a geologist. And do you specialise in volcanoes? Is that... I did. Yeah, back, you know, feels like it has decades ago now. But I started out as a geologist because I was fascinated by volcanoes. And I'm just wondering, how do you... If you're a geologist at all, how could you not be fascinated by volcanoes? Well, exactly. That reshapes your planet, right? Exactly. I think the thing for me was that I didn't even really know what geology was when I was at school, because you don't really do it as a core subject. And then I learnt about volcanoes and was fascinated. And I read this amazing book called Surviving Galeris by this volcanologist called Stanley Williams. And it was his story about how he'd gone up this volcano and it had unexpectedly erupted. And he'd taken all these people with him and ended up in his dire circumstances. And lots of people got killed and injured. And for some reason, that really inspired me to... It was amazing. And I was like, I don't know why, because I don't consider myself a risk taker. But I just really was fascinated by them. And I then learned that actually I needed to do geology to... So the fact that volcanoes can kill you or industry at a level of respect... Yeah, completely. ...personally, emotionally and professionally. And just to be clear, Matt, in case you didn't know, a volcanologist... It's not about Spock or anything from Star Trek. Go there. Just want to make that one clear. But am I right in thinking that you also thought in your career that a volcano is on Earth just a little bit too dull? Well, you know, there's always that, because we know so much about the pandemics. It's not true. I mean, the thing is with my book, I've dedicated, you know, almost half the book to the volcano's on Earth, because we know them so much. Well, I mention that yet. You have a book called Fire and Ice. I do. Oh, I know. I don't know if I got that in there. Yeah, yeah, yeah. It's supposed to let me talk about your book. No, you talk about your book. Fire and Ice, it's a great title. And is it... Like, as Matt saying, you were not content with just volcanoes on Earth. No, no, no, no. I'm just talking, because after I did my geology degrees, I moved into space science. So I was basically doing chemistry on volcanic rocks to understand how the earth formed. That was kind of my PhD thesis. And then I discovered that actually you could do the same chemistry on rocks from space. So that led me to analyzing pieces of comics and asteroids brought back by space missions. And so it kind of broadened my horizons. I've never really thought about studying anything from space before. I never thought that was really an option for me. But then suddenly I'm combining all of these expertise. And so it kind of led on after my first big which was about comics and asteroids. And I wrote all about those first. Then I was like, hold on, I'm going to combine this all and write about volcanoes in space because it just seemed like the natural thing to do. And let the world know, if they didn't already, that you wrote the current space show at the Haydened Lanatorium called Worlds Beyond Earth. So thanks for agreeing to do that and bringing some of your expertise across the pond as we say of the Atlantic Ocean. And we were delighted to collaborate with you on that. So thanks for bringing that collective expertise. If you were just a geologist, no, we wouldn't have had you. Yeah, thank goodness. We needed that space dimension that you brought to the table. And that was such a fun show to write. Oh my goodness, I learned so much in the process as well. Like having to combine that kind of scientific expertise with basically space artists, people that can image this stuff that we write about and we talk about so much. And using all that kind of real data from NASA and eSemissions and using it to create this beautiful show. It was, yeah, it was a great experience. Yeah, all your words on the page are actually happening visually on the dome. Yes, yes, yes. And so curious about something, is there a, we know when we think of volcanoes, we think of hot things. And so why is the word ice in your title? Yeah, good question. OK, so a lot of people don't realize that actually most of the volcanoes out in the solar system, particularly when we go past the asteroid belt out to Jupiter and beyond. Most of the bodies out there are actually ice volcanoes. So these are active places. Wait, wait, wait, wait, wait. You're just thinking like, OK, yeah, most of the volcanoes in the solar system, yeah, this one. Like do people even know we have volcanoes other places than Earth? Oh, I'm sure they do. Really? I'm sure. I might have had a vote. I don't know. I would say maybe a fair proportion, a large proportion of the listeners of this show would know it. But I think if you poll the average person on the street, I don't know if you would necessarily think of a volcano as being on other planets. I don't know if you'd even necessarily think of. Maybe I've spoken to many platforms. The people think Earth is flat. They're not thinking that they're volcanoes elsewhere. So I just have issues with believing that this is why it's spread. Even people who have, you know, who have accept broad acceptance of science, but maybe answers as embedded in it. I would even say, this is even something. It's obviously I know that the heat from volcanoes and the most rock isn't fire, per se, but the idea of something that looks like fire coming in a vacuum in places that don't have air, that seems very interesting. So all of this, okay, so we have fire in vacuum and we have ice in volcanoes. So explain yourself, Natalie. Yeah, so I mean, I used fire, you know, to kind of just represent the fire in this old volcanoes. And it's something I go into in the book a lot, but we can also use it to represent, you know, there are lots of fire evil canos out in the solar system. We had active worlds around us. Mars was massively active kind of three billion years ago. Venus on external neighbor is probably still active today. It's probably got volcanoes erupting today, we think, but we just can't see them happening. But there's a lot of evidence that it probably is happening. Why can't we shoot? Well, lots of issues with Venus. It's not a very nice place, basically. It's really hard to see. It's covered in this shroud of gas, basically, of carbon dioxide, which means so it's atmosphere is really thick and dense. So it's really hard to see through it. You can't see through it with visible light. You need like a radar to see through it, which we've done. We've sent spacecraft up to look through that really dense atmosphere and we've looked at the surface of Venus. And we can see it's just covered in lava flows. So everything that's on its surface is basically basalt, which is the same kind of stuff that we find in places like Hawaii and Iceland, very, very standard volcanic rock that we see a lot on our own planet. But the whole of Venus is about the same age. It looks like it's about 500 million years old, which sounds really old, but actually in kind of the age of the solar system, that's not very old. It's been active quite recently. And just to be clear, you call Venus our neighbor, but Mars is our neighbor too. I mean, when we're talking about Venus' similar size. Yeah, it's just the important thing is that it's a similar size to Earth. And it was made of the very same ingredients as well, the terrestrial planets, all the ones within the inner solar system. So it should be very similar to Earth. Like we should expect it to be very similar to our own planet, but it's not for some reason. It's turned into this hellhole. It's got a surface temperature of 450 degrees Celsius hot enough to melt lead. It's got horrible pressure on the surface. So the Soviet spacecraft land there decades ago. And these spacecraft lasted just a few hours on the surface before it was being crushed to death. So it's not a place we're going to be sending humans anytime soon. But it's a fascinating world because what we want to do is understand why it's ended up so different to Earth. Like why hasn't it got oceans on its surface? And that's one of the big questions that we actually trying to look at now. We're sending some missions there. NASA are going to send two missions there in the next decade. ESA are going to send one mission. I think the Indians have another mission going. So your PM Space Agency. Correct. Yeah. And so we're going to find so much about Venus now. So it was Mars. I feel like Mars has had its day now. Like we've done it. No, we haven't. There's lots still to find out about Mars. But Venus is going to be the next planet we're really going to delve. And just to shout out to India, who's joining the fray there with sending probes to planets. So yeah, they've done some amazing work there. You know, there's space agencies doing great. So there's going to be so much information coming back. It's really exciting. It's amazing. Now what is ice fit into this? Oh, yeah. I went off on the tangent. I was attentive. But yeah, the ice part is going to represent all those volcanoes that are past the asteroid belt. So we've got basically a lot of moons around these giant planets out in the outer solar system. So we take Jupiter, Saturn, Uranus, and Neptune. They've all got lots of moons around them. Like Jupiter has about 79 moons that we've found so far. So it's just loads of them. You know, we've just got one. And I'm like, OK, Jupiter's kind of greedy, but it is a big planet. Well, I'm not made of those moons kind of lame excuses for moons. No, not at all. I would say ours is a bit lame now. Now we've learned about all these other ones. Like, the new ones. I meant just in terms of how tiny they are. No, no, no, no, no, no. I told you. So some of the moons out there are actually as big as Mercury. No, I meant among the 79 moons of Jupiter, some of them are... Some of them are not potentially so interesting. But if we take the Galilean moons, we've got I.O. We've got Ganymedia, Roper. These are all really cool places. I.O. is hot. It's very much like Earth was kind of four billion years ago. It's for the most volcanicly active object in the solar system. So it erupts these plumes of rock almost continuously off its surface. In fact, every space mission that's gone by has seen it erupting. But then all the other moons there are kind of icy moons. So they've got these rocky interiors. But then they're either ocean worlds with an ice cap on the outside or they're just made of ice. And these are the really interesting ones. Because in order to have sort of an ocean underneath the ice, we know that they must still be warm inside. That rocky interior must still be warm somehow. It must be warm enough to heat the ice to turn it into a liquid. And so this instantly tells us that these worlds are active and interesting places to go. And sure enough, the more we've looked, the more we've discovered that they have volcanoes on the surface. So they have plumes of material shooting out from their oceans, which shows us that there's a lot going on beneath the surface. So we can call us ice volcanoes, I guess, is that right? Yeah. So that ice volcanoes are like cryo volcanoes, cryo being the cold parts. And there's loads of them everywhere. Everywhere we look. So actually, it's almost like the ice volcanoes are more common than the kind of the hot ones that we see in the inner solar system. So you're looking at this. It's like long overdue. Somebody should have been talking about this long ago. It should be like in all the classes. Well, this is the thing. It's quite, it's almost quite recent that we've really learned about all of these places. In fact, you know, the Voyager missions went out in the kind of 1970s and 80s. And before that, we had no idea that these places were active. In fact, we didn't even know some of these means existed. And as we got out there and we started to photograph them, we were then very surprised by the results. So I was at school during that time. And of course, that was, you know, cutting edge research happening at the time. That's not going to be in the school curriculum. So it takes a while for that to kind of filter down. But what we then discovered was actually some of the data that Voyager got. And we didn't see some of this stuff at the time. So it needed kind of reprocessing. So we go back with other missions later. And we spy this plume shooting off the surface of an cellar just somewhere. And we can go back to earlier data that is still sitting in the archives and reprocess it and go, Oh, look, we would have seen it there. If we'd looked more carefully, we now have loads of evidence that these things have been active for decades. So really, it just takes incremental steps of missions going out and discovering this stuff. But we've barely been out to the outer solar system many times. Like we've been there just, you know, a handful of missions. So there's still a lot more. This is an interesting fact that if you do flybys, you just have these snapshots of a moment in time where you then have to generalize what the thing is doing all the rest of the time, which could be very hard. Like I'm trying to think of an alien flew by Earth. And I just happen to be in the bathroom when that happened. You generalize my whole life. Well, he lives in the back. Like at least another data pointer. Something to capture that. Matt, did you collect questions for us for today? Well, so I think you've sort of half answered this already. But I just want to pin down this question from Adam Smith just to kick things off. Because he says, is there such a thing as cold volcanoes or ice full camels? I imagine ice things spat out like in the way Mr. Freeze did in the 1997 Batman and Robin film, character play by Arnold Schwarzenegger. Or is this a logical or tutor, pressure causing heat? I mostly wanted to ask that question because of how detailed he went in with the specific intensity of film. He needed us to know exactly which iteration of Batman and Mr. Freeze used. Yeah, because you don't want to get confused with some other rendering and play by a different character. Actually, we got to do a quick break. But when we come back, we didn't get Natalie to explain to us how an ice volcano actually works. Because that's a mystery to all of us here when we come back on Star Trek. I'm Joel Cherico and I support Star Talk on Patreon. This is Star Talk with Neil deGrasse Tyson. We're back, Star Talk Cosmic Veries. Fire and Ice. I've gotten Natalie's Darky as a book with that title, geologist, turn astro person. But what she worked on became interesting when she stepped out into space. That happens whatever you're doing on Earth. If you add space to it, it's more interesting. That's my bias. That's your bias to Natalie, isn't it? He had definitely. Okay, there you go. Matt, you left off with a question about Arnold Schwarzenegger, was it? Yes, this is from Adam Smith. There's a lot of Batman-specific parts of the question, but the main part is, what is the deal with ice volcanoes? Does ice get spat out from these volcanoes? Is this logical due to pressure causing heat? Yeah, because pressure, whether or not pressure even causes heat, pressure wouldn't have to cause heat. It just has to be pressure, right? If you look at it out of a volcano, it doesn't have to be heat that does it. Is that right? So, no, yeah, this is kind of a tricky one to answer. It's a great question for that reason. But basically, there's lots of different ways that volcanoes can erupt. And I think what we need to get away from is thinking having to think of a volcano is a conical shaped mountain like we see on Earth. Because actually, when we go out into space, we don't need that. We don't need a conical shaped mountain to have a volcano. Because we have to just define better what a volcano is. We're sort of skewed towards what we have on Earth, because that's what we first study the volcano. So we think they have to look a certain way, but we go out into the solar system and we look at these other objects around us and we start going, okay, well, this is a volcano. This is material coming out from the inside of this world, and it's spewing out onto the surface. And that's happening because there's heat within inside that world, and it's producing a molten material or gas, and it's forcing it, objecting it out. And that is basically a volcanic type of activity. So we see this at Enceladus. Basically, what's happening there is that there is heat generated within that world, because as Enceladus goes about, it's all bit around Saturn. It's sort of pulled and pushed on the inside by the gravity of Saturn. So it kind of gets a bit closer, a bit further away from Saturn. And so it's called tidal heating. It's very much like we get with the Earth in the Moon, and that we kind of squash slightly in our Tides move. But within Enceladus, for example, they actually insides of it as squash. So it's rock creates friction and heat, and that then heats the ocean above it. And eventually kind of opens cracks in the surface, that then allow material to escape. So you'll see it as a plume. That material ends up raining back down onto the surface of Enceladus, and resurfacing that body. But not only that, but these are kind of what we're actually spewing out is basically gases, ice particles, little pieces of silica grains, which come from the very bottom of that ocean. And some of these ice particles actually start to make Saturn's e-ring. So they get sent so high up into space that that is the reason we have Saturn's e-ring within which Enceladus kind of all bits. So that's, yeah, a much longer answer, and that's only one way that we can kind of make volcanoes on these bodies. But yeah, in a way, I kind of think that's like the Mr. Freeze character that we're spewing out ice particles into space. And that's by sampling those, which we did with the Cassini mission, we know where they're coming from, because they're salty. We know they're from a salty liquidation below the crust. So that's really cool. So if there was fish there, could fish be spewed out too? You know fish in the e-ring? Yeah, exactly. I love this. Now that we've eaten that, this. I was just kidding. You're telling me that's like, well, many... But living in things could be shots out. Anything could. So whatever's down there is going to come out in these plumes. Now the thing is when Cassini went, it didn't know, it needed to measure this stuff that was coming out in the plumes because we didn't know that were happening. So this is one of these things with space missions. We then learn stuff, and we go, oh, we need another mission. We need to go back and specifically look at these plumes and the material that's in them. What we do know is that there's all the right materials for organic content being there. So we know that there's chemical reactions happening within that ocean that can create organic molecules. Now it's a step then to say, okay, we need to find a life. But there's every chance that it could be down there. It's got all the right conditions for life to form. Okay, not human life, but other kind of life that we might find at the bottom of Earth's oceans, for example, which is going to be a very similar environment. So, yeah, every chance we need to get down there and have a look, basically. So it must be hard enough for a fish in Earth ocean to be caught, you know, with a line. And then throw them back and have to explain to other fish what they saw. That's going to be hard enough. And now we're going to have a fish spewed into orbit around Saturn when they were happily swimming beneath the ice. Yeah, just be sort of orbiting around the fish on the ground. On the ground is like, get back, get back, get back here. Crazy, crazy. Still messing around. All right, just to fight. So there you go. All right. So Matt, what more do you have? That's a great, that was a great question. It might be just take away from your answer there is that the Batman or Robin film was scientifically accurate. So that's nice to know. I like the, I always love it when a question comes from the children of listeners. I like the idea that there's some young kids who are interested in this stuff. So this is from Wes Denham's seven-year-old son, Silas, who asks, what is the process that magma goes through to be able to rise to the surface before it explodes? Oh my goodness. What a question. That's amazing. I always love the ones from the kids because they're always the hardest to answer. You're like, oh, it's, you know, it was like, oh, it'll be a really simple question. Like, no, that's not a simple answer. Well, I just be clear that what you call magma, we call lava, is that right? So yeah, basically magma is before it's erupted. So below the surface, if we have molten rock, it will be called magma. As soon as it goes off the surface and erupted out of a volcano, it becomes a lava. People know it's the same stuff. You just have to do a word for it. It's exactly the same stuff. And then after it hardens, then you call it basalt. Well, it, yeah, it will be a basaltic lava. And then when it hardens, it's a basaltic rock or basaltic acid. Yeah. So, you geologist, damn, darn it. Oh, I know. You just like to make life complicated. Okay, so, okay. So now let's answer. And who's, who asks this question again, man? This is Young Silas, seven-year-old son. By seven. Oh my gosh. Okay. So, let's go to the outer solar system and go to these icy worlds. Remember our view of volcanoes is skewed towards what we have on Earth. So we think volcanoes need to be rocky. And then we go out there and go, oh no, they don't. They can be icy. So, basically, when we talk about magma or lava on, for example, Pluto, let's take Plutics. That's a great example. It's not rocky. The stuff that Pluto has made, oh, it's all ice. So when we talk about Pluto's magma, it's basically just the molten version of whatever it's made of. It's made of ice, bedrock, water ice, an ammonia, and methane, nitrogen. So when we melt those materials, which it's easier to do, because they have lower melting points, we basically make magma or lava of those materials. So that's their magma, that's their lava. So it just depends where you are. We just need to center ourselves from the right world. So whatever happens, basically, you need to heat the stuff. So if you've got rock within a side of planet, which we do, if you delve down into our planet, it's hard and it's rocky. We need to melt that stuff in order to make it rise. As soon as you make a liquid of a solid thing, then it's more buoyant. And it just wants to naturally rise through that body. So that's generally what happens. Now, the other thing with magma is that they often contain a lot of gases. And these gases just want to escape. So they kind of overpressure this magma as it rises up. And that causes it to just keep rising and keep rising and melting its way through the crust until it gets to the surface. And then basically what happens is those gases want to just erupt out of that lava very quickly. And that's generally what makes the explosion at the surface. If we see something, you know, like mountains and hellens or somewhere, that was just that magma basically exploding as it got to the surface and blowing that mountain apart. And as that pressure is released when you get to that moment. Well, wait, so if the explosion blows a mountain apart, how do we get the mountain in the first place? So the mountain initially was built up from very continuous eruptions of lava and ash. And so we call these stratovolcanoes. So they generally build up quite slowly over years and years. And then you know, trees grow on them. And they look just like a mountain. And we don't think that's scary. And this is partly why volcano is very dangerous because they have a very nice shape. Oh, it's beautiful. Yeah. You know, I loved with the Olympics coverage. Yes, it was gorgeous. It was beautiful. They used that image or time and snow cat mountain. And I think that is the volcano that looks most like a child's dream. Yes, exactly. It doesn't even look real, right? It's right. Yeah. Yeah. It's beautiful. I think that's why we sort of forget as humans because these, you know, volcanoes kind of erupt not very often, but they're still class as active. So 10,000 years is usually the time frame where we say, if it hasn't erupted for 10,000 years, then it might be not actively longer. But the problem is we don't as humans remember that kind of time frame. So people live close to volcanoes for many different reasons. The land around volcanoes is often very fertile. So it's really good to make crops and everything in grow stuff. And also the land is cheap because it is known not to be very safe. Really, you think? But people have to live in these places. Location, location, location. Exactly. And they're beautiful. So, you know, I would quite like to do this. That's good school. It's got good roads, but you're on the side of a volcano. As much basil, so see me. We went on a trip to Italy and visited Vesuvius, you know, famous Rupope. And no, there's no lava there that I saw, but it was hot. We wouldn't hear the cow dare. It's like, oh my gosh. Yeah. I was like, whoa. And that obviously is very famous for palm trees. Very famous instruments. Is it the ruins? Yeah. Yeah, yeah, of course. Of course. And their vineyards on this side of Vesuvius that are thusfully identified on the label. So if you want to get a, so it tastes a bit of ash. I think I don't know. That's the thing about ashes. Really, it's really, really good for soils. So, you know, whilst a huge amount of it coming down the mountain like at Pompeii, you know, is rather devastating. Small scattering of ash quite often, a really great for soil. And it has this great ability that it can absorb water into the soil. So it acts as like a fertilizer in the soil and helps to create these amazing crops. That fertilizer and irrigate it, right? Very interesting. Yeah. Cool. Yeah. So this is Nicholas Godlov. And along these lines, Nicholas is asking, should we be worried or afraid of the super volcanoes of Earth? And what is the most menacing volcano to you in our solar system? Good work. Okay. So yeah, super volcanoes, that's a grace of jet because we hear about, I think Yellowstone is probably the most famous one we hear about because it's always, you know, in the media. Oh, it's going to erupt. You know, it's going to erupt next year and it's going to devastate everything. But the reality is that thing of like it, it's due is how it's always just going to. It's going to be due. Like a two in eruption. And it is always due, you know, but because we don't have a huge amount of data of how often it's erupted, but the thing is with these super volcanoes is if they do go, it would be massively devastating and they create cold-dira eruptions. So you don't really see anything on the surface initially. You don't see a volcano like Mt. Fuji. What will happen is that the ground will literally just explode and you'll end up with this massacled dira left behind. And that has happened throughout history. But the thing is with these things. But that area still has good schools, right? We can still build those out. It could blow up completely, but before that happens, you got... The thing is with super volcanoes, whilst they have the potential to do that, and we think there's a massive magma chamber sort of under the surface that could be bubbling away, let's say, and potentially going to erupt. You're geologists, why don't you know this? Or you're a big... We can thump the ground and find oil. Why can't you thump the ground and find where the magma chamber is that might bust? So we know that. We can do seismic surveys. We know sort of where the ground is hotter and where there's molten material, but it doesn't mean it's all going to erupt in one go. It could be that it has smaller eruptions and let's sort of be a steam and then there's another one. And so they wouldn't be devastating and therefore it lets off the steam and then it's not going to erupt for, you know, the million years. So then almost never as bad as we think they're going to be. And if one is really going to erupt, then we're going to know about it. Because we're studying them in detail and we'd have a good idea if it was going to do something. Okay, that's encouraging because otherwise, so it might erupt to the next 4,000 years. That's not helpful. Yeah. You're saying it. I should say it. And how about the other half of that question? What was that? I've already forgotten. Oh, that was what is the most menacing volcano to you in our solar system? Menacing! Oh, but I don't like to give the menacing titles because either are lovely. But now I'm not. I'm not. I guess it's going to be. It actually feels for the volcano. They don't have feelings for you. They will melt you in an instant. Okay, they prize you. I guess I wouldn't want to be sitting on I.O. Because I think on I.O. you're almost certainly going to be captured by an eruption somewhere. And even if not, you'll have probably lavish, battered on you from one of its erupting volcanoes. And it surfaces just incredibly hot. So what about I know it's not active, but Olympus Mons on Mars. Isn't that the biggest volcanic mountain in the whole solar system? Yeah, it's massive. It's like three times higher than Mount Everest. It's absolutely enormous. But the thing is, it's not much different to Hawaii. So the volcanoes that we see on Mount Alora and Manakia, it's a very similar type of volcano. And actually, they're not particularly scary. When it erupts, I think the most recent bigger eruption was kind of 2018, people were able to outwalk the lava most of the time. Yes, it was devastating. It covered houses and land, but you could outwalk it. So just to get me. I never heard that sentence before. Let's outwalk the lava. It's going from my stroll. Morning constitutional away from the burning rocks. Very cool. So Matt, let's slip in one more question before we take our second break. All right. Well, I'm going to give it that we're talking about Olympus Mons. There are two questions, two different people have written in questions that include that. So Cameron Bishop asks, what properties determine the size of a volcano? And how did these properties allow Olympus Mons to get so big? Could such a volcano form here on Earth? And Jared Sober says, if Olympus Mons was able to grow so large due to Mars' weak gravity, why don't we see even larger volcanoes on other active bodies, such as some of the larger moons? Yeah, brilliant. So yeah, and that second question's got it exactly right. So Mars is about half a size of Earth, so it has less gravity. So it means that things can simply just grow bigger. So if we took a Olympus Mons size volcano or mountain and put it on Earth, it would basically collapse under its own weight because it would just be too heavy. And so it just, it couldn't form here. It would literally just wouldn't be able to get that big. So the other way that Mars has been able to grow such a large volcano is because it doesn't have plate tectonics. Now, I'm hoping most of the listeners are going to know what plate tectonics is. It's a thing that's very unique to Earth, we think. And it's where the outside of our crust of our planet is basically broken into pieces which move around in relation to each other. And they can kind of knock into each other or they create earthquakes when they slide past one another. And they are what creates many of our volcanoes. And by the way, just to be clear, y'all only fully embraced that within the last 60 years. That's not a forever ago thing. Yeah, it was literally, I think it's the 1960s, wasn't it? Yeah, it was 60 years ago. It was suggested that it was a thing and people were like, no, the man's crazy. Yeah, no, I think it's suggested predate that, but before the evidence really gathered to start. I didn't know that. And I also really didn't know that Earth was the only body that we know of that has this. I thought it was a fairly universal. No, so that's how we get lots of our volcanoes. But the other type of our volcanoes, luckily, come from mantle plumes. And this is the type, again, Hawaii is a classic example. This is a big chimney of hot rock that rises from the interior of the Earth, possibly as deep as the core. And it comes all the way up through the planet and then erupts molten lava at the surface. And these are very long live features on our planet. Now, if you just imagine this chimney of rock in the planet and these plates are moving over the top of that. So what happens at Hawaii is we get this chain of volcanoes. This chimney of rock keeps erupting and the plate moves over it and we get a volcano's going along in a linear chain. So the most recent ones are Mount Loro-Mannicaea. Now, in Mars, we've got exactly the same thing here. Yeah, so this is an archipelago, right? Isn't that what an archipelago is? Yeah, exactly. And many of the Caribbean islands are. So what you're saying is it's not a continuous busting through of the plate. It busts through and then it stays calm for a while and over that period, this plate shift. And it's okay time to bust through again. There you go. And so that completely, but that's fascinating to me. Because in my head, these sort of chains of volcanoes, I assume they were like all along a fault line or something like that. Yeah. And you're saying it's more or less more like a sort of like a factory line where they're moving up. Like the Earth is moving along on a conveyor belt. So every soul that it touches the whole truth and it moves on a bit more and punches another whole truth. And so if you go to Honolulu and people are like, oh, it's volcanic, could it erupt? You really know you can't because it's nowhere near that plume now. So that is almost certainly not going to happen. But then other island, that's the one. Yeah, I thought we need to worry about with the molten lava crater at the top. Yeah. And also, I think I'm right in that the big island in Hawaii would not be sustainable where that fully on land. Yeah. And then the buoyancy of rock and water allows that to build as high as it did through from the bottom of the ocean through the ocean surface and then above the ocean surface. Because it doesn't weigh as much simply because it's half of it is sitting in water. Yeah, exactly. Yeah, because I think people forget with those islands that you know what we see above is not even half of it. And in the middle of the freaking Pacific Ocean, right? Yeah, we're very deep. We got to get another quick break, another quick break. And when we get back, Matt, you got more questions for it, Matt. We're going to be starting. Our geologists turn astro person, Mickey Perch, on Star Talk. We're back, Star Talk. We're going to be able to get a little bit of the grass Tyson here. Matt, where can we find you on social media? You can find me at Matt Kershian on the various things and probably science is my podcast. Okay. And that's on all the podcast. We're ever a podcast or soul near you. Yes, okay. Yeah. Yeah, I'll ask you your local book shop for a microphone. Yeah, there you go. And Natalie, where can we find you on social media? I'm at Starkey Star Dust on all the platforms. Okay. Starkey Star Dust, ST-A-R-K-E-Y. Yeah. Starkey Star Dust, I love it. Yeah. Yeah. So, I think we had to take a break before you completed the answer to why Olympus Mons is so big on Mars. So, we learned that the Hawaiian chain of islands, they're all volcanic, and that's just magma punch and through in a new spot. As the plate tectonics take it by. So, Mars, I think, doesn't have plate tectonics. So, is that what happened there? Yeah, we don't think it does. We haven't got any evidence for it there. Now, obviously, it's not an active planet today, so we know it's not happening today. Try and work out whether it happened in the past. We just don't have any evidence for it, so we don't think it did. So, we call it a stagnant lid planet, basically just one big crust and it didn't move. So, what happens there is, if you've got one of these mantle plumes coming up from the interior of the planet onto the surface, that plate isn't moving anyway. It's just going to carry on erupting for millions of years in the same hole. Through the same hole. Through the same hole, maybe even a billion years or more. So, yeah, it just grows larger and larger and larger in one place, and that's exactly what happened with Olympus Mons. All right, cool. Cool. Which is the largest volcanic mountain in the solar system I think? I think it's the largest mountain, isn't it? Yeah, yeah, yeah, yeah. Good, good. All right, Matt, keep them coming. Okay, well, this is a question Chester Lipschitz has sent in that touches on both of your areas of expertise. Do today's volcanic activities have much of any impact on the cooling down and gradual solidifying of the core? If so, how long would it take? Would we lose our ability to maintain a stable magnetosphere and atmosphere before we even have to worry about the problems the sun is going to give us in a few minutes? Oh, wow. What a compartical elevator. Did you get any sleep at night? Right. So, I think he's basically then asking, like, as heat is coming out through these volcanoes, is it cooling down the inside of the earth? And is it doing it at such a rate that it's going to start changing how the earth is? And let me simplify that question to Natalie. Why is earth still hot? Yeah, no, that's like clear. So, the volcanoes are basically just a manifestation of a planet cooling itself down. So, it has all this internal heat, and it needs to go somewhere. And volcanoes let that heat escape into space. Which means we are cooling down. So, but luckily, we have plenty of heat. So, we've got two main two types of heat in most of the planets. So, the heat that was left over from the formation of the planet. So, when the planet's formed, it was all a bit chaotic. And things were colliding with each other. And basically, kinetic energy of two objects colliding into each other turns into heat energy. And so, it gets trapped within the cores of most of the planets, or all the moons, in fact. So, we've got a lot of heat from four and a half billion years ago. And it's been trapped in ever since. Outside of the core, we've got a mantle, which has made up of silicate rocks. So, these are kind of the basalts and stuff we were talking about. That's a really good insulator. So, it keeps that heat inside the planet. The larger you are, the more heat you can retain. Now, the other way that we create heat is actually continuous process. And it's nuclear heat. So, we've actually got radioactive decay going on within our planet. Basically, atoms that are unstable, decay to more stable atoms. And they release heat during this process, because they release little atoms. And they release little atoms that then collide with other things inside the planet and create heat. Now, it sounds like it wouldn't be very an important process. But actually, there's so much decay going on in the planet that we're creating about half our current day heat from that process. So, why is it Mars could also create a heat that way? So, it is. But it's cooled down a lot more now, because it started off smaller. So, it never had as much heat to start with. And then, because it's mantle is smaller and it's crust where it has all these heat producing elements. It then has just lost that heat. So, we have volcanoes and Venus. It starts volcanoes and we're resistant plants. Exactly. Yeah, and this is probably a similar temperature inside. We talk about the surface temperature of the plants. It almost doesn't really relate to what's going on inside. So, mercury being right next to the sun can even have ice on its surface. So, I love that. And another side of that question was, if it does cool down, we might lose our magnetic field. Because you drive a magnetic field by the movement of conducting materials. Yeah. And when you move charges, within an electric field, you can generate a magnetic field. And so, we rely on a molten inner region of iron. It's self-conducting material to generate a magnetic field. It's shield zest from certain forms of solar wind that could then strip our atmosphere of very molecules that we care about. Including the water molecule. So, did I characterize that accurately there? Yeah, perfect. Our outer core is actually molten and our inner core is solid. So, it's that molten iron rotating around inside the planet that keeps our magnetic field alive. And without it, we wouldn't be here because life would be bombarding with radiation. Or we'd be living just underwater. We may be living underwater because if you had an ice cover, like you find at your repair, which is obviously sitting next to Jupiter, which has this horrible magnetic field if you're a life. It can't be the truth. Otherwise, it just bites it. If you're a rock, what do you care? If you're a robot, then you might be in trouble as well. So, that's what it can say. Yeah, and that's we do have to really protect space equipment that we send out from radiation in space. Because all this can damage cameras very easily. So, yeah, it's something we have to worry about. But Mars, if we go back to Mars, it did have a molten interior and then it no longer does. So, it's lost its magnetic field. So, this is why we talk about life might have been there in the past because it had all the right conditions. But it also means terraforming Mars might have bigger challenges than we think. Because you might be able to turn it into Earth, but to sustain it requires the rest of this shielding to happen. Yeah, we've been completely intelligent caves and I think it would be miserable. But, you know, maybe people want to go and do that. But we would need to live underground to protect ourselves using the rock to basically shield us from the radiation. Okay. So, my favorite thing about this show is I can make a stupid joke about robots. In terms of that, I actually have to say something to Mars. That's a very insightful point, Matt. Thank you. That's what I was going for. I appreciate that. Two scientists there. Okay. Keep you coming. Well, she had a few more questions. This is also touching on Neil's expertise as well. Because Mark as Gustafson says from Sweden asks, can asteroids develop volcanoes? And would that make it all bit unpredictable because of the thrust in regenerating? Oh, cool. That's really cool. And yes, yes, yes, it can. So, we've actually discovered that some of this, the asteroids, like, some series and actually that's what ice volcanoes on it. And there's a mystery called psyche, which is a NASA mission. I think I don't know when it's launching not not long now. It's going to this asteroid called psyche 16. And they think it had ion volcanoes on it, potentially way in, way in the past. Now, whether those volcanoes have to be clear, I don't want to be pedantic or anything. But series got upgraded in its designation in the solar. It's true. I'm like, please. Yeah. So little got downgraded from planet. Series got upgraded from asteroids and they're both dwarf planets now. So, yeah. So, I will not accept you to cite series as a place for asteroidle volcanoes. It's in the asteroid bell. Oh. I'm going to call it an asteroid. It's a two-on-an asteroid. Okay. I guess this location does matter to geologists because magma outside of a volcano is called lava. Exactly. That's how you roll. So also, of course, comments as they come near and far from the sun, plumes will develop that do alter their trajectories. Yes. So, with comments predicting their orbits is a highly risky, not risky, it's highly uncertain activity simply because you don't know where the next plume is going to come out that will then have the comment recoil and give you a different kind of orbit than you were expecting. Yeah. And when they go near the sun, they can explode or pieces can come off. And then obviously there are different size and shape to what they're having before they went on the sun. I know. It's crazy. I'm just blown. To disintegrate or get eaten by the sun entirely. Yeah. Like Matt, wait, time for a few more. Well, a little bit. Yeah. Well, this is obviously the counterpart to this question from, and I hope I'm getting your name close to correct. Zenkutti Benz asks, can an eruption have such power to send rocks to space? If a giant eruption happened in Yellowstone, would it send rocks to space, which would then fall back down on Earth? So the second part of that question and that question comes from hungry. Yeah. So I guess once you're in space, you're not going to probably come back very easy, but that wouldn't really happen on our planet because we've got so much gravity that I just don't think we could have a strong enough power for an eruption that you could get out into space. But obviously in other places, we know that in salad, it's plumes, you know, go 200 kilometers high and make the e-ring of Saturn to sure enough that is, you know, eruptions going into space. I may be wrong, but I don't think that could happen on Earth, but sure enough, like, eruptions do go very high into the stratosphere quite often with these plenium-style eruptions, which is what happened at Vesuvius. And the material then, the ash and the gases kind of encircle the planet, but within, you know, our atmosphere and can block out the sun for weeks and months to come. And that can create lots of kind of long-term damage to the planet in a way. Also, even if it did eject from the volcano at escape velocity, the atmosphere is going to tamp that down, and it will not likely ever escape the Earth, because it won't maintain that velocity as it ascends. Or maintain the velocity necessary to continue to escape the Earth. But there's more than one sci-fi film where we have astronauts on comment surfaces and on astroidal surfaces where it rotates into view of the sun. There's a plume that busts forth, and people hardware is, get kicked completely off the asteroid, never to return. Yeah, and then it's something they worry about with comet missions, with the Rosetta mission. They landed on that comet, and they had to choose somewhere that didn't look very active. Didn't have, you know, an active plume coming out, because, you know, they were genuinely worried that the spacecraft, you know, little lander would get shot off the surface and be lost into space forever. So it is quite a worry. That'd be a cool video though. We, we like, like R2, you know, getting kicked out of the thing. I guess in the sci-fo world, if you're thinking about it, if you do have an ability to predict where these plumes are going to come from, that's a possible launching site. Oh, I feel by using that as a... Very good, man. That's a traveling. Oh my gosh, so that would have to be a desperate situation where, how do you, how are we ever going to get back? Wait a minute, there's a crash here. Let's do that, and then that saves them. They remind me, there's a movie called Marooned, where it's back in the 60s, before we landed on the moon. And there's some astronauts in space, and something goes wrong, and they have to be rescued. But a hurricane was coming through Florida and over Cape Canaveral. So they couldn't launch a rescue mission, and then someone figures out, wait a minute, the eye of the hurricane is going to go over Cape Canaveral. So they connected the countdown to the... I was very young, so I didn't know hurricanes at eyes. I didn't know any of that is beautiful in the middle of a hurricane. I didn't know any of this, or that Florida was hurricane prone, right? And so they actually launched into seeing this launch coming out from the center of the hurricane. That was beautiful, that was a beautiful concept. I'm not sure how exactly they wheeled the rocket out through the hurricane. If I know anything about rocket launches, they're quite easily disposed to take motion. Doesn't take much for them to say, like this isn't safe, we need to wait another couple of months. Yeah, but it was cool, it was a cool move though. Yeah. Okay, I can't wait. Time for a couple more questions. Maybe one more question. Time for one more question, man. Okay, well, I like this one, because there's been some other questions that I think we've covered anyway, just three questions, things that have come up naturally. So Boris Mechanic, again, I'm a mechanic, I hope I'm getting you on the close, says, okay, here's a silly impossible, possibly ignorant one. I say it's not ignorance. I'm the one who asked the ignorant one. Yeah, Boris, stay in your lane. But there's only one room from one ender in first in the show. But Boris, is it possible that a regular mountain can become a volcano or a hundred percent of volcanic mountains, shapes and masks created by the first direction itself? Yeah, yeah. So once you've just got a normal mountain and is created to be normal mountain processes, which is usually from plate tectonics. So we've got two plates colliding and nothing gets melted. They just kind of crumple up against each other because they're being forced together, you know, a few centimeters per year. That's how we get the Himalayas. So those mountains and, you know, Mount Everest are not volcanic. They never will be. They're just getting taller and taller every year because, you know, those plates are crushing together and pushing up crust above the surface. So, no, sorry, no, no big mountains will become... So the subcontinent, no, it didn't get the memo that, like, rushes in the way. Yeah, exactly. It's like, I'm still moving, I'm still going. It's just taking it going. So Natalie, I'm wondering, in the vein of that question, could we actually take a spot on Earth and drill to where the molten rock is and sort of force of volcano to erupt? Where we choose it to? I guess if we knew the magma was there, that would technically... Not technically possible because that would be... You're a geologist. You know where this stuff is. Drilling into hot stuff is never going to be easy because other things are going to melt anyway. But, like, if we knew there was a magma chamber there, we probably know if volcano is there anyway. Like, you're not going to just get a magma chamber without a volcano. But actually, what we do do a lot is kind of use the heat that's given out by these magmas sitting below the crust to generate electricity. So in Iceland, they do this a lot. Iceland is obviously all volcanic. It sits on the mediation region. It's also got a mantle plume there. So it's a massively volcanic place. And they generally... We've been feeling many scenes and cosmos there. Oh, because... Because you have... It looks like the... You aim the camera this way. It's like, Earth is forming. The aim of here is like, there are these plumes. Where's the dinosaur? You know what I mean? We had all manner of Earth formation scenarios without any kind of set design. It was all already there. And the great thing is that there's so much heat, just literally just under the crust there. That they just generate all their electricity for free, because they can use geothermal energy. So they pump down water into the crust, it gets heated up and get shot back up. And they could use that to... By the way, as I heard, that was only in recent decades until the burgds, I think, they were still using fossil fuels. And somebody said, what the hell are you doing? You brought the heat. Yeah, I do that with it. And then I... I think... I actually sent heat on their roads. I was going to say, because it is cold. Yeah, they sent heat on their roads and it melts all the ice. So they're not going to show up. Yeah, they don't have to grit the roads. I found out recently that Iceland has the highest electricity use per capita of any country in the world, like, quite some way, which makes them sound like they're not green, but it's the opposite, because they do everything with basically fossil fuel-free electricity. Yeah, and if you just tap and heat out, you can leave the lights on. And then they... You can have all these saunas everywhere and hot swimming pools and everything. So they have loads of swimming pools, just because they can heat them really easily. And they're all outdoor pools and, you know, when it's really cold, and you're like, oh, that's going to be horrible, but it's great. Right, right. And what's that? So let me... Just to end with, can I reverse that question? And... If... I heard that the name of a fraternity... I mean, it was a joke name. It was called, I tap a keg, right? Okay, so... Can we... Can there be a volcano that we think is going to erupt? And then can we tap it off the side and have it kind of like a release of the pressure to delay what might be a larger singular eruption of the cone? No, I think the problem is we just still don't know enough about volcanoes to be able to predict their behavior. Damn, Emily, I thought you knew... I'm going to try my best. I'm just a pointy, okay. But basically, with a lot of volcanoes, like there's the Montserrat in the Caribbean as a classic example. It's this volcanic dome, which sits above the surface, but it's really unstable. So, you know, even a lot of rainfall can destabilize the slopes of that volcano, because it's just not very well consolidated and mashed together. And that can destabilize the magma chamber underneath and then create a massive eruption. So, basically, you're taking off kind of the lid of the pressure cooker a little bit. You're just releasing a bit of pressure and then it can then erupt really badly. So, we would have what a medal. I think we have to leave nature to do its thing. And the best way for us to get away is just to move people away from the world. That's so defeatist. Wait until your kids become geologists. And they say, Ma, that's so old fashion. Yeah, we just tap this energy here. We run the energy needs of the town. We get the volcano will never erupt and we got to wear good. Wait till the next generation. They'll figure it out. But there is one possible, I don't know if you have time, but just to squeeze in one extra question, from Moses Conrad Norman, who lasts. Can you have a planet that is entirely volcanoes on volcanic activity? Yeah, I guess Io is the closest part of that. Yeah. And it's almost like our planet four billion years ago. So, our planet four billion years ago was almost certainly covered in volcanoes. And most of the surface was just very hot, probably molten. And volcanoes were going off all over the place. So, that is what's happening at Io Still. It's not quite that bad, but it is very, very active. So, yeah, like you're definitely, it's just, it's got, again, it's got that kind of tidal energy inside, because it's right next to Jupiter, this massive planet. So, it's being squashed and squeezed, friction is happening inside, and it's creating heat, and that's just a continuous process. And let me just put this to bed right here. So, in the old days, we would, well, maybe even in modern times, we would see drawings of dinosaurs. And there was always a volcano on the horizon. As though dinosaurs, which was 100 million years ago, somehow Earth was covered with volcanoes, 100 million years ago. But that's like yesterday compared to the geologic timescale. So, they're, that's all wrong, I guess, is correct. Yeah, I mean, yeah, the werewolf cano is obviously at the time, but not like that kind of era that we see where they're just, you know, it's all volcanic. Right, right. It's not every direction to look. There's a dinosaur chewing the plants. Yeah, yeah. And stuff and plants don't like volcanoes very much. But there are dinosaurs on IO. Well, the model we said, Matt, we haven't seen them yet. We need to hurry here first. All right, we got to call it quits there. Natalie's always great to have you. And again, thanks for being the author of our current space show with the Hayden Planetarium, World's Beyond Earth. Matt, we'll find you on probably science. Still waiting for my next invitation to appear as a guest. The second, the second you have anything you want to come on and talk about, if you, your next book, or just just a whim, you are the door is wide open for you. All right, but very pleased to hear that invitation get extorted from you. Very much the other time. Anytime. Anytime. I'm Neil deGrasse Tyson, director of that Planetarium. We're Natalie Starkey, wrote the latest space show. As always, it's for Star Talk. I think you keep looking out. Thank you.