Daniel and Kelly’s Extraordinary Universe - What's the most powerful volcano in the Solar System?

Episode Date: May 6, 2021

Daniel and Jorge break down how volcanos work and blow up your idea of what makes a powerful volcano blow. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

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iHeartRadio app. Search all the smoke and listen now. Hey, Jorge, have you ever seen hot lava in real life? I've been to see the volcanoes in Hawaii. Yeah, how close did you get to the actual lava? Pretty close, like, you know, a few feet, I touched it with a stick. You actually touched the lava? With a stick, yeah. And did you love it?

I did, although I'm not in lava with it. Thank goodness for that. It is pretty hot stuff, though. Hi, I'm Jorge. I'm a cartoonist and the creator of PhD comics. Hi, I'm Daniel. I'm a particle physicist. I'm the co-author of the book. We Have No Idea. And I'm a big fan of chocolate lava cakes. Well, so much information there. First of all, you wrote a book. I did. I wrote a book with this friend of mine. You should check it out. It's pretty funny. What's a call again and where can I purchase it? It's called We Have No Idea. It's about a all the grand mysteries of the universe,

everything we don't know about science and physics and the universe, everything that we love talking about on the podcast. And I wrote it with you and it's filled with fantastic, hilarious little doodles and cartoons that explain the physics and also make you laugh, just like this podcast. Oh, well, cartoons and comics, sign me up. And also, you like chocolate lava cake?

What? It's a chocolate made out of lava, or is it lava made out of chocolate? It's lava made out of chocolate, I guess. You know, it's a cake that you bite into and this molten chocolate flows out. Burns your tongue, but it's so delicious, you don't mind. Basically just undercooked chocolate cake. Yeah, those were super popular while back.

I guess they're still popular. With me, they still are. But welcome to our podcast, Daniel and Jorge Explain the Universe, a production of I-Hard Radio. In which we take a big bite of the lava-filled deliciousness of the universe and try to explain all of it to you. We think about all the crazy stuff that's out there. We zoom down to the tiniest little particles that are jiggling,

and wiggling and made out of strings. We talk about the whole shape of the universe and its future and what might happen to it and to you. And we do all that while making some banana jokes. Yeah, and hopefully without burning your tongue because physics is pretty hot, understanding the universe, learning about it. It's all pretty amazing and hot stuff.

It is hot stuff and we like to see it explode out of your mind and flow out through your life. And I love hearing from listeners that they have had their excitement for physics tickled by listening to the podcast. Yeah, we like to talk about all of the small stuff out there in the universe and all of the huge stuff out there that you can find and you can discover. And especially we like to talk about extreme things in the universe. We definitely do because we love to ask questions about like how hot can something get

or how big can something be or how small can we see things. These extremes of the universe are what tells us what's possible. They are the places where the actual rules of the universe might be revealed. And so we love to explore these crazy extremes. Yeah, we have a whole series of extreme podcast episodes. And that's where you cue the heavy metal guitar music. Extreme universe. Cha Ching sponsorship from Mountain Dew right there.

I wish. But yeah, we have episodes about the coldest thing in the universe, the biggest thing, the shiniest thing, all kinds of the biggest, most extreme things. I don't think we've done the shiniest thing yet. That's a great idea. Well, I guess we have the brightest. We do have the brightest. And we have the fastest spinning thing and the hottest thing and the coldest thing and the emptiest thing and the densest thing and all the thingiest things out there in the universe.

Right. We still haven't done the silliest thing in the universe. Siliest thing in the universe? I'm not sure that's a physics podcast topic. Isn't it? What if you define silliness in physics terms? You know what? Probably there is some concept in physics that has nothing to.

to do with silliness, but it's called silliness anyway. It's like another quark charge or something. Silliness and boringness. This one has two sillies, and that one has negative one and a half borings. And there's the Whiteson rule, which says that no two nerds should have a silly podcast at the same time. We're breaking that rule right now. It's what it's all about.

So yeah, we like to talk about extreme things. And so today on the podcast, we'll be tackling the question. What's the most powerful volcano in the solar system? Now, Daniel, powerful doesn't end with an EST. Oh, yeah, that's true. The most dramatist volcano in the solar system. Most powerfulest, powerist? Well, you know, that's a linguistic problem, you know.

Some of these adjectives, you can't add EST to them. But you're still extreme because you're still the most something. I guess adding the most helps, grammatically speaking. All right, so the question is, what's the most? powerful volcano in the solar system. Now, Daniel, I think you picked this word very carefully because you didn't say, what's the hottest volcano or largest volcano. You said the most powerful volcano.

I did. I thought about powerful volcano because there's lots of different ways to describe volcanoes, right? You know, and I'm not that interested in like the biggest volcano if it's like inert and not doing anything anymore. It's basically just like a dead volcano. So I wanted to know about like the most dramatic, the one that's going to explode the most, the one that's like really going to blow. up in your mind. So I thought about most powerful volcano.

The burpiest. Yeah, exactly. The one with the worst indigestion. The gaseous. Exactly. The rudest, maybe. All right, well, it's a pretty big solar system. I imagine there are a lot of volcanoes in it. And so we'll talk about all of the ones here on Earth, all the ones in the solar system. But as usual, we were wondering how many people out there maybe had an answer to this question. So thank you to everybody who volunteers to answer these random physics questions from me with no preparation, really appreciate it. And if you would like to participate, don't be shy. I promise it's fun. Write to me to questions at danielanhorpe.com and you'll hear your guesses on the podcast. What could be more fun than guessing at difficult physics questions

in front of thousands of people? You know, you'd be surprised when I used to walk around campus and ask people, it was almost never people said no. Like everybody was up for it. They're like, sure, whatever. I wonder how they would feel if you told them how many people would listen to this podcast. And whether or not that number would impress them or make them feel bad for us. There's definitely a reason why I try not to look like a famous podcaster when I walk around campus. Well, I see. That's on purpose.

It's just my natural look anyway. Is there a look for successful podcasters? Like, what are we supposed to look like? I don't know, but this definitely isn't it. That you know. Or maybe the more successful you are, the less dressy you have to look, right? I mean, I feel like in LA, that's true. Like, the more successful you are, the more like you don't care how you dress.

Maybe I dressed like Seth Rogen, right? So I might as well be Seth Rogen. But, you know, we have one listener, Mark Fearing, who's also a cartoonist. And he once drew our portraits just based on hearing our voices, like what his mental image was of us. Wow. And what did we look like? Well, I looked like this big barrel-chested guy wearing like a tweed vest and pontificating with a big pipe coming out of my mouth.

So I look pretty pretentious. And how did he get it right for me? I think he didn't know that you have a Chinese background. Didn't somebody once say that we looked like the guys from, what is that show called? Flight of the Concords. Flight of the Concordes, yes. Well, that show is hilarious. So I would be glad to be compared for that show at any level.

But anyways, we're talking about volcanoes. And we were going to ask people on the street what they thought was the most powerful volcano in the solar system. Here's what they had to say. I don't know, but I'll just guess that it's on. The most powerful volcano in the solar system is actually me after a night of binging on Taco Bell. No, I'm kidding. Actually, I think it's on a moon, one of the icy moons that's got a bunch of heat generated by gravity from Jupiter or Saturn and something like that. That is a good one.

I don't know about specific volcano, but I have a hunch it would be on. on Jupiter's moon, Iowa. So we're not talking about the highest volcano. Olympus Mons on Mars is extinct. So I'm thinking that gravitational tides on a moon of a gas giant would drive tremendous eruptions. Maybe a water volcano on Europa or a methane volcano on Titan.

I'd say the most powerful volcano in the solar system would be the volcanoes on I.O. Because when they go off, they shoot debris, clear out into space that then gets sucked up to form a ring around Jupiter. So I would say the most powerful volcanoes are the ones on I.O. I would guess that that would probably be on Venus, but I don't know what the name of it is. I know that the moons of Jupiter have pretty strong volcanoes and active. But I also know that Mars has won.

one big volcano with that one is not active. It is probably in the sun. There's the dead one on Mars, Olympus Mons. And then around Saturn, there's the moon Enceladus, which is ejecting like ice and stuff into the space. And that's kind of like a volcano. All right. I like the person who said that they're the most powerful volcano in the solar system.

That person needs to find a new taco truck. Don't want to be around that person. That is not a good sign, my friend. But nobody said any volcanoes on Earth. People just assumed that the biggest, craziest, most powerful volcanoes are somewhere else. I guess I think you said in the solar system. So that kind of tips you off that, you know, to get to the extreme stuff, you have to go outside of the planet. Well, I'd like to know what's the most powerful volcano in the universe, but we have no idea what's out here beyond the solar system.

So that's sort of just like the limits of what we could probe, right? The universe, huh? I mean, there must be a more powerful volcano somewhere else just because there are so many planets. Is there a theoretical limit to the biggest volcano? Do you know what I mean? Like at some point, wouldn't it collapse into a star or something? Theoretical limit could like a whole planet be a volcano. You know, that's pretty cool.

And if so, then what's the biggest volcano planet you could have? Dun, dun, done, new podcast episode idea. I guess I'm getting ahead of ourselves. But yeah, so let's tackle this question, Daniel. And I guess the first question is about the term. So you said you post the question as the most powerful volcano, not the hottest, not the burpias. So what does that actually mean? Well, when I was first thinking about this, I was imagining dramatic explosions, right? We all know about like Mount St. Helens or other big explosions in history that have killed lots of people and been very dramatic and pumped a bunch of stuff into the atmosphere. So that's sort of what I had in mind at first. But it turns out there's two very different kinds of volcanoes. There's the ones that like explode and blow their top like we're talking about. And they have like one. really big eruption. But then there's sort of the slow and steady kind of volcano that sort of leaks lava continuously over many, many years, like the one you visited in Hawaii. And those could

actually be much more dramatic and influential on like climate. So there are two types. Yeah, exactly. So the kind in Hawaii, for example, is called a shield volcano. This is the kind of volcano that sort of slowly leaks lava. Like the volcanoes in Hawaii don't just explode and then stop. There's a continuous flow of lava. And that's because this lava doesn't have a lot. lot of silica in it so it's very fluid so it doesn't like build up and then explode and what you get then is this it's called a shield volcano because it basically just sort of like flows down hill and spreads out you get this very flat sort of volcano shape not your like typical cone volcano it's very broad and flat so it's sort of like a shield laying on the ground but it's still unpredictable

right like you can build up pressure in them and sometimes you know the top collapses like i've been up there to the top of some of the ones in Hawaii and, you know, things change. Like one year I went and there was this whole landscape and then the next year I went and the landscape was gone. Yeah, absolutely. And they're constantly producing more landscape, right? It's like a continuous flow. But you're right.

It's variable. It's not like exactly continuous. You know, and these things definitely have cycles where they're more active and less active. The one Kilao in Hawaii, it produces like 2.7 cubic kilometers of lava, which spread out covering like 100 square kilometers. over about a 30-year period, but it has ups and downs and times you're right when it's producing more and times when it's producing less, but they're not like really the dramatic explosions that you're used to seeing like in cartoons, for example.

You don't like the giant sprays of lava, that's not this kind. Yeah, exactly. So Shield volcanoes put out a lot of lava, but sort of like in a more continuous slow flow because of the kind of lava they are. And, you know, in history, they've been very important. Like there's one in Siberia that probably caused like the Permian extent. An event that killed like 70% of all species on land and spread its lava across like an enormous area of the earth. So I don't mean to put down shield volcanoes like they're very powerful.

They're very important. But they don't have like this sort of momentary dramatic explosion the way the other kind of volcanoes that we call like stratovolcanoes are. Wait, so that one in Siberia, how did it kill so many species? Well, just spread lava across like a huge plane. Where 70% of the species were? It wasn't just the lava. It also released a lot of mercury into the atmosphere and raised the temperature of the earth by like 10 degrees, which can upset a lot of ecosystems. But it definitely can affect like, you know, the course of life on Earth.

All right. So then the other kind, is it called a sword volcano? The other kind is called a stratovolcano. Strato because there's like lots of layers in it. There's like layers of magma and then other kinds of rock and sort of builds up slowly. And this kind of volcano is much more eruptive because it has a different kind of lava. The lava has more silica in it and more dissolved gas. And so it's sort of like stickier.

It's gooier. And so it doesn't like flow out of the crack in the earth as easily. It tends to more like build up. And then when the pressure builds up underneath it, then it blows. And so this sort of goo leads to like a much more dramatic explosion. Right. And it's gazzier too, right? Yeah, exactly.

It releases enormous quantities of rock and lava and also gas and smoke. And they can also have big effects on climate. We'll talk about a few. examples later on. All right. So those are the two kinds here on Earth or anywhere. Does that apply to all other planets too? Those are the ones that we have studied best on Earth. And we'll talk about the ones in other bodies in the solar system. And you'll see that they're not really a fair classification for talking about what's happening on other planets because the process is really very, very different. You're not even always talking about lava. Sometimes you have very low gravity

environments. And so it doesn't like build up the same way it does here on Earth. So volcanoes on Earth are pretty different than volcanoes on I.O. or on Titan or in other places. I see. They're more alien. But the way the geologists sort of rank volcanoes or talk about volcanoes power, they use this metric. They measure like how much stuff comes out of the volcano. Like what volume of stuff has it emitted? At a single time or over time? Because you just said that there are kind of two kinds, like one that's steady and flowing and the other kind that it's more explosive. Yeah. So it's sort of a judgment call, but you integrate over the eruption. And if If it's a shield volcano and the eruption is sort of continuous, then you can measure its power just by the volume of lava produced.

If it's an erupting stratovolcano, then you can measure its power by the volume of stuff produced in that eruption. And then, you know, it goes quiet for a while. And so you sort of know when the eruption ends. But I guess even if it's the erupting kind, the stratovolcanoes one, the fact that it's not erupting is not because there's no lava sort of coming up from the ground. There is. It's just building up, right? Exactly. Both kinds have sort of a steady flow of lava.

Exactly. Both of them are places where there's like a big pool. I think actually it's called magma before it comes out of the ground and then it's called lava. But they have this pool of magma underneath where there's like a crack in the crust and it's sort of getting closer to the surface and that pressure can build up. And that's one problem with this metric of measuring a powerful volcano basically by the volume of its greatest explosion. There could be a volcano out there that's like about ready to go and is much more powerful than any volcano on Earth. It just has. has never blown up, and so we don't know that it's there. And I guess, you know, maybe just to take a step back, where is all this lava coming from? Is it just the molten center of the Earth, or is it a particular layer? And why does it come up? Doesn't gravity pull it down? Yeah, well, you know, the Earth is many, many layers,

and you have the crust, and then underneath that, you have the mantle. But the crust is not of uniform thickness, right? And so there are places, for example, when the tectonic plates meet where there are gaps, and it's easier for things that are molten inside the Earth to come up. For example, a lot of the volcanoes on Earth are actually underwater, and they exist where these tectonic plates meet in the ocean. And so you can get a lot of volcanoes there. So typically, they're just places in the Earth where the Earth's crust is thinner and this molten magma can bubble up. I guess all that stuff is under pressure, right?

Because on top of all that lava, molten center of the earth, there's a bunch of tectonic plates pressing down at it. And so if you have a crack, then it's going to leak out some of that lava being squeezed underneath. Yeah, the reason that it's liquid is because of the pressure. When you have some heat from like radioactive decays of isotopes from the inside of the earth, but mostly it's gravitational pressure. Like think about why is the sun hot. The sun is hot because it's being squeezed and then that squeeze and creates fusion. The earth doesn't have fusion, but it's still being squeezed and that creates an enormous amount of pressure.

And that pressure can create friction. And that's why you have liquid inside the earth. All right. Well, let's get into what are the most powerful volcanoes, not to say. here on Earth, but in the solar system. But first, let's take a quick break. December 29th, 1975, LaGuardia Airport. The holiday rush, parents hauling luggage,

kids gripping their new Christmas toys. Then, at 6.33 p.m., everything changed. There's been a bombing at the T-Earling. EWA terminal. Apparently, the explosion actually impelled metal glass. The injured were being loaded into ambulances, just a chaotic, chaotic scene. In its wake, a new kind of enemy emerged, and it was here to stay. Terrorism.

Law and order, criminal justice system is back. In season two, we're turning our focus to a threat that hides in plain sight. That's harder to predict and even. harder to stop. Listen to the new season of law and order criminal justice system on the iHeart radio app, Apple Podcasts, or wherever you get your podcasts. My boyfriend's professor is way too friendly, and now I'm seriously suspicious. Oh, wait a minute, Sam. Maybe her boyfriend's just looking for extra credit. Well, Dakota, it's back to school week on the OK Storytime podcast, so we'll find out soon.

This person writes, my boyfriend has been hanging out with his young professor a lot. He doesn't is a problem, but I don't trust her. Now he's insisting we get to know each other, but I just want her gone. Now hold up, isn't that against school policy? That sounds totally inappropriate. Well, according to this person, this is her boyfriend's former professor and they're the same age. And it's even more likely that they're cheating. He insists there's nothing between them. I mean, do you believe him? Well, he's certainly trying to get this person to believe him because he now wants them both to meet. So, do we find out if this person's boyfriend really cheated with his professor or not? To hear the explosive finale, listen to the OK Storytime podcast.

on the IHeart Radio app, Apple Podcasts, or wherever you get your podcast. I'm Dr. Joy Hardin-Brandtford, and in session 421 of Therapy for Black Girls, I sit down with Dr. Ophia and Billy Shaka to explore how our hair connects to our identity, mental health, and the ways we heal. Because I think hair is a complex language system, right? In terms of it can tell how old you are, your marital status, where you're from, you're a spiritual belief. But I think with social media, there's like a hyperfixation.

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and we had a blast. We talked about her recent 40th birthday celebrations, co-hosting a podcast with her fiancé Sue Bird, watching former teammates retire and more. Never a dull moment with Pino. Take a listen. What do you miss the most about being a athlete. The final. The final. And the locker room. I really, really, like, you just, you can't replicate, you can't get back. Showing up to the locker room every morning just to shit talk. We've got more incredible guests like the legendary Candace Parker and college superstar AZ Fudd. I mean, seriously, y'all. The guest list is absolutely stacked for season two. And, you know, we're always going to keep you up to speed on all the news and happenings around

the women's sports world as well. So make sure you listen to good games. with Sarah Spain on the IHeart Radio app, Apple Podcasts, or wherever you get your podcasts. Presented by Capital One, founding partner of IHeart Women's Sports. Or are we talking about the hottest volcanoes in the solar system, Daniel? The most powerful. It's about power. Who has the most influence on the course of history? Yeah.

or who can just blow the most stuff into the atmosphere because that's really how they measure it. They're not like how many people did you kill or how many square kilometers did you cover with your lava and just like what's the volume of stuff that you blew up out of the top of the mountain. But you just told me a little earlier that powerful is measured by the amount of lava flow,

which could be like steady and not that exciting. It could be, but you measured by the volume of lava. But I guess what I mean is you could have a really powerful volcano know, but it's just oozing kind of constantly, it's never exploding or throwing things up into the atmosphere, but it could still be the most powerful one. Yeah, if it's producing a lot of lava, then by this definition, it would be the most powerful. It wouldn't be very dramatic and it wouldn't be exploding, but it still would be the most powerful. Or do you mean, like, are we sort of adding an element of drama to the word powerful, like the most lava in the shortest amount of time?

No, I think as we said earlier, you just measure how much stuff has been produced. And so Kilauea, for example, has been produced. using stuff for a long time. So it racks up like a good amount of lava, like three cubic kilometers, which sounds like a lot, right? But it turns out that even these shield volcanoes that are constantly leaking what seems like an impressive amount of lava don't hold a candle to these strato volcanoes, which can release just so much more stuff in a short amount of time. All right. Well, let's get into what have been some of the most powerful volcanoes in our history here on Earth. And I guess Mount St. Helens is kind of at the top of the list, at least in terms of the consciousness of the population.

Yeah, it's one that people can talk about and think about because it happened sort of in recent history. We have like television footage and pictures and all sorts of stuff. So people sort of connect with it. It's a pretty small event on sort of like the top list of volcanic eruptions in Earth's history, however. So it's the deadliest and most economically destructive in U.S. history, but it's not actually that impressive. Only three cubic kilometers of stuff was blown off the top of the mountain. I guess the U.S. is not that old. I mean, it's like 200 years old compared to, you know, the age of the earth.

And so to say that the most, it's the biggest one in U.S. history doesn't go back a lot, pretty far. No, it's just a blink. I mean, that's very impressive. Like, imagine three cubic kilometers of lava. It's a lot of stuff, right? It blew off the whole top of the mountain. The top of the mountain is now like a one mile wide crater. So this is nothing to sneeze at.

It's just not that big compared to other crazier events in Earth's history. And Mount Sinhalans was a. strata volcano that kind of builds up and then explodes. Yeah, and there were some hints that it was going to explode. There was like an earthquake a couple months before and it cracked the volcano and there was like steam coming out and people could see

the top of the mountain changing shape. It was like bulging. So people were pretty well clued in that something was going to happen and there was a lot of like volcanologists that were around watching it. Unfortunately, a lot of them underestimated the power of it. Some of them tragically died in the lava flow because they were too close.

Oh no. They didn't live long and prosper. They did not, exactly. No, so it killed like almost 60 people and it destroyed a bunch of homes. I guess maybe people didn't think that it was going to blow up or, you know, were they just sort of like, oh, look, it's blowing out smoke and it looks swollen. Let's take more pictures. Yeah, they thought it was going to blow, but just not that bad. You know, they didn't expect it to be as dramatic as it was.

They underestimated its power. Classic mistake. All right, so that's Mount St. Helens in 1980. What else do we have in our history? Well, the most powerful recorded volcano in all of human history, right, which is, you know, not that long. We're talking maybe 10,000 years, is only a couple hundred years ago. In Indonesia, there was this volcano, Mount Timbora, which blew up in 1815. And it's famous because it deleted a whole summer.

It's called the year without a summer. What? I can relate to that experience this past summer. This past year, feels like it was erased. It blew up so much material into the summer. sky went all around the world that it basically caused a volcanic winter. This happened in April and so basically summer just never came because the sun was blocked. You had like winter spring, no, back to winter and then roll right into fall. We had like snow in New York in June. The whole

temperature of the earth dipped a measurable amount because of this one volcano. So when they say like when it snows in July as a saying it could happen and it has happened. Exactly. And it affects. affected, you know, crops and hundreds of thousands of people died as a consequence of this volcano. People like died of starvation. A lot of people died in the immediate aftermath because it was very dramatic. You know, Mount St. Helens blew three cubic kilometers of debris. This one blew 200 cubic kilometers of debris up into the air. I guess that's kind of what happens, right? When you block the sun, things get cold. Yeah. You basically put a shroud. The whole earth basically got a big shroud and we couldn't get sun so we couldn't have summer. It was a pretty crazy event. It blew off

the whole top of the mound. It lost like almost 5,000 feet in height and it like dropped stones that are 20 centimeters wide on the nearby villages. So it was pretty insane. You could hear it happening like a thousand miles away. That's pretty powerful stuff. Exactly. So that puts Mount St. Helens really to shame. All right. So then what else is on our list of most notorious explosions on Earth? So that's as far back as we can look sort of in recorded history, but we can look back in the geological record and see evidence of more powerful volcanoes. So there was this event 75,000 years ago, again in Indonesia. And geologists think this was the most powerful volcanic blast in the last million years.

Mount St. Helens blew three cubic kilometers. Mount Tambora in 1815 blew 200 cubic kilometers. This one, we think, blew almost 3,000 cubic kilometers. of stuff into the air, causing a volcanic winter about 10 years long. 10 years? Like, no summer for 10 years? No summer for 10 years. And it cooled the whole Earth and its impact lasted almost 1,000 years.

Is that sort of related to the Ice Age? The Ice Age, I think, is a separate event, but this definitely contributed to the cooling of the Earth. And we think it kills a lot of humans. There's also separately this evidence that humans had a genetic bottleneck 70,000 years ago. If you look at everybody's DNA who's alive now and try to reconstruct where they came from, it turns out that it looks like the whole human population comes from a very small group of people around 70,000 years ago. They call this like a genetic bottleneck. We all

have like the same ancestors, a group of about like maybe 5 to 10,000 people that lived about 70,000 years ago. And so like there's a lot of debate and discussion in the field about whether one thing cause the other, but it might be that this eruption killed a lot of the extent humans only leaving a small population, which then were the ancestors for everybody who's alive today. So we come from survivors of this volcanic explosion, yeah? Yeah, exactly. Well, by definition, we all come from survivors, but this almost wiped us out, right? It could have been the end of humanity. Yeah, I mean, it killed everyone except like 3 to 10,000 people. That's not a lot of people. That's like a small town left to repopulate the entire Earth. Yeah, exactly. And they got busy to

doing it and it took 70,000 years, but hey, they did their duty. They got busy, wink, wink. It's a big job, but somebody's got to do it. Yeah. And so what's this volcano called? It's called Lake Toba and it's in Sumatra, Indonesia. And that's the most powerful eruption we think in the last million years. Just from the like geological record that we can study, but that we can see too, right?

But there'd be things hidden underneath, you know, jungles or the ocean floor. Yeah, that's how they find this stuff is they dig down through layers of sediment and they see like ash laid down and you can tell like exactly how much was deposited because it's like still there. You see these dark layers in the sedimentary rock and you can tell what happened. And they also they can look down at ice in Antarctica and stuff and they can measure the global temperatures, the amount of snowfall and stuff like that. That's how they know what the temperature was, you know, 75,000 years ago. All right. What else is on the list? Another really powerful set of eruptions happened right here in the United States about two million

years ago in Yellowstone. Yellowstone is famous, of course, for these geysers, old faithful and all sorts of stuff. So you know there's like a lot of heat going on underneath. But it turns out that Yellowstone lies over like a hot spot. It's like a thin spot in the crust. And there's all this hot magma that rises up from the mantle very near the surface and sort of heats everything up. Are you saying Yellowstone is a volcano or was a volcano?

Yellowstone is a volcano. It's like could blow at any time. And in the last 20 or so years, people have been, like, measuring the level of this magma. And it's been rising and rising and rising. And some people saying, oh, Yellowstone is like due for an eruption. That's hogwash. We don't really know when Yellowstone will erupt again. The last time it erupted was about 640,000 years ago in a pretty mammoth eruption that released like 1,000 cubic kilometers.

But over the last 2 million years, it's erupted several times, many of those times just as large as, Lake Toba or even larger. Wow. So that could have also maybe taken out our species. Yeah, but I don't know what humans looked like, you know, two million years ago, what the evolutionary tree was. And it's harder for us to predict that and then to calculate that. But yeah, absolutely, it definitely affected anybody who's living anywhere nearby. These eruptions produced enough ash and lava to fill the Grand Canyon. Like, these are mammoth events sort of in world history. Kind of makes me wonder what might have been, you know, what could humans have looked like those other humans that survive, you know? It could have been taller or better looking or smarter or more susceptible to volcanic eruptions.

Yeah, it's cool to think about how like random moments that could have been different really shaped the path of life on Earth. You know, the asteroid hits the earth and kills the dinosaurs and all those kinds of events, including volcanic eruptions, have really shaped where we are. And we don't know right now if where we are is sort of like what would have happened in most circumstances or if it's just like a totally rare and random occurrence. So it's fascinating to think about all these things and to look at volcanic activity on other bodies to understand, like, are we lucky or unlucky? Do we need this kind of volcanoes to sort of like keep evolution fresh? Or has all this volcanic activity prevented things from progressing more quickly? Right. Or should we invest in that giant volcano plug idea?

I think if you plug up a volcano, you end up just putting it off and it's a bigger explosion when it happens. Not if you plug it really good, Daniel. But maybe the biggest eruption in the history of the earth that we know of happened even further back in history. There was this eruption 132 million years ago. What? Yeah, down in what's now South America. But this is before South America split off from Africa. This is back when there was like different set of continents.

This continent called Gondwana, which is, you know how sort of South America tucks into the little armpit of Africa there? Yeah, yeah. Yeah, so it used to be a single continent and it was split apart by tectonic activity. And they think that about 132 million years ago, as sort of part of that splits connected to when that split happened, there was this enormous set of volcanic eruptions right around there. And if you've ever been to like Iguazu Falls and Paraguay, it's very close to right around there. And so this was a huge event. It probably put out like almost 9,000 cubic kilometers of lava. Guess you, you know, these continent shifts and these motions and splitting of continents,

they all happen because of volcanic activity, right? It's all sort of like magma and, you know, earth turning down there and moving things around. Exactly. So this volcanic activity is very closely connected to these cracks in the Earth's crust, these intersection between the plates. That's why we think, for example, there's probably like a million submarine volcanoes on the ocean floor putting out lava constantly, all these little cracks where these things are happening. And I guess thankfully they're under water, right?

They are underwater, but they actually make a really weird kind of lava because they come out and they cool really quickly when they hit the water, they make these weird blobs and they're called pillow lava. Right. They look kind of like, you know, bubbly. Yeah, they look a little bubbly. And so what the lava looks like depends a lot on what happens when it comes out. Does it like dribble down the side of the mountain and make a bigger Hawaiian island or does it make a, you know, fluffy pillow underwater or does it get like shot out into space? because it's at the top of a really tall volcano. All right, so that's the biggest one. And what's the name of these volcano of all volcanoes?

It's a whole region down there, and it's called the Pirana and Itandeka Traps. And it's down there, still in South America, there's a lot of volcanic activity sort of under Iguazu Falls and that whole area. This one was like a huge explosion. Are you saying it was like a network of explosions or was it just one ginormous explosion? There's a lot of discussion about that. As you might be able to guess, it's hard to tell exactly what happened, 132 million years ago so the evidence isn't conclusive and some people think oh this was like a network of volcanoes some people think it was one mega explosion geologists still argue about it at conferences

but i guess it didn't extinguished life on earth because we're still here yeah it didn't and interestingly it doesn't seem to coincide with like mass extinction so even though it produced a huge amount of lava and probably put a bunch of stuff out into the atmosphere it didn't kill off a bunch of critters that we know off what if there are you know species that we had no idea about it could be but you know they look at the fossil record sort of before and after, and you can line up like extinction events with volcanic events sometimes. And sometimes there are volcanic events with no extinction events where you see like the same kind of critters alive before and after the eruption. All right. Well, that's volcanoes on planet Earth. Let's get into what are some of the most

powerful volcanoes in the solar system and see if we can beat some of the ones here on Earth. But first, let's take another quick break. December 29th, 1975, LaGuardia Airport. The holiday rush, parents hauling luggage, kids gripping their new Christmas toys. Then, at 6.33 p.m., everything changed. There's been a bombing at the TWA terminal. Apparently, the explosion actually impelled metal, glass. The injured were being loaded into ambulances, just a chaotic, chaotic scene.

In its wake, a new kind of enemy emerged, and it was here to stay. Terrorism. Law and Order Criminal Justice System is back. In Season 2, we're turning our focus to a threat that hides in plain sight. That's harder to predict and even harder to stop. Listen to the new season of Law and Order Criminal Justice System on the IHeart Radio. app, Apple Podcasts, or wherever you get your podcasts. My boyfriend's professor is way too friendly, and now I'm seriously suspicious.

Oh, wait a minute, Sam, maybe her boyfriend's just looking for extra credit. Well, Dakota, it's back to school week on the OK Storytime podcast, so we'll find out soon. This person writes, my boyfriend has been hanging out with his young professor a lot. He doesn't think it's a problem, but I don't trust her. Now, he's insisting we get to know each other, but I just want her gone. Now hold up, isn't that against school policy? That sounds totally inappropriate. Well, according to this person, this is her boyfriend's former professor and they're the same age.

It's even more likely that they're cheating. He insists there's nothing between them. I mean, do you believe him? Well, he's certainly trying to get this person to believe him because he now wants them both to meet. So, do we find out if this person's boyfriend really cheated with his professor or not? To hear the explosive finale, listen to the OK Storytime podcast on the IHeart Radio app, Apple Podcasts, or wherever you get your podcast. I'm Dr. Joy Harden Bradford, and in session 421 of therapy for black girls, I sit down with Dr. Afea and Billy Shaka to explore how our hair connects to our identity, mental health, and the ways we heal. Because I think hair is a complex language system, right, in terms of it can tell how old you are, your marital status, where you're from, you're a spiritual belief.

But I think with social media, there's like a hyperfixation and observation of our hair, right? that this is sometimes the first thing someone sees when we make a post or a reel is how our hair is styled. You talk about the important role hairstylists play in our community, the pressure to always look put together, and how breaking up with perfection

can actually free us. Plus, if you're someone who gets anxious about flying, don't miss session 418 with Dr. Angela Neil Barnett, where we dive into managing flight anxiety. Listen to therapy for black girls on the IHeart Radio app, Apple Podcasts, or wherever you get your podcast. Get fired up, y'all.

Season two of Good Game with Sarah Spain is underway. We just welcomed one of my favorite people and an incomparable soccer icon, Megan Rapino to the show, and we had a blast. We talked about her recent 40th birthday celebrations, co-hosting a podcast with her fiancé Sue Bird, watching former teammates retire and more. Never a dull moment with Pino.

Take a listen. What do you miss the most about being a pro athlete? The final. The final. and the locker room. I really, really, like, you just, you can't replicate, you can't get back, showing up to locker room every morning just to shit talk.

We've got more incredible guests like the legendary Candace Parker and college superstar AZ Fudd. I mean, seriously, y'all. The guest list is absolutely stacked for season two. And, you know, we're always going to keep you up to speed on all the news and happenings around the women's sports world as well. So make sure you listen to Good Game with Sarah Spain on the Iheart radio app,

podcasts or wherever you get your podcasts. Presented by Capital One, founding partner of IHeart Women's Sports. All right, Diana, we're talking about giant, powerful volcanoes, and they don't just happen here on Earth. They happen on other planets and even in other moons. Yeah, exactly. And our solar system, it turns out, used to have a lot of volcanic activity. We think the moon might have had volcanoes.

We think Venus might have had volcanoes. We know that Mars used to have volcanoes. In fact, one of the largest mountains in the solar system is on Mars, Olympus Mons, and it's a shield volcano, but it's dead. And most of these things, the moon, Venus, and Mars no longer have any volcanic activity. I guess, you know, it's a natural part of just being a planet, you know, like having, you know, pimples as a teenager. You're like, it's a right of passage almost for all planets.

Because all planets start off is molten, and then they get crusty and cool on the outside, and that exhorts pressure. And so inevitably, you know, all planets, I would imagine, get volcanoes. Yeah, I think that's probably true. They're all molten at some point. I guess a rocky one, sorry. I guess you need to be a rocky planet to have volcanoes. You need to be a rocky planet. It also requires a special configuration.

You have to have like this crust, which holds the magma in, but is thin. enough that it can like crack and it can bulge. And you also have to have like a liquid core. And so Mars, for example, we don't think it has any more volcanoes, but we don't actually know whether it still has a liquid core. Some people think it's totally cooled and some people think there's still like magma underneath dying to get out, but the outside trust is too solid to let any volcanoes bubble up anymore. I see. Or too thick maybe. Like it could just be too dense or something. All right, well, take us through a tour of volcanoes in the solar system. Well, it's really exciting that there are volcanoes in the solar system

because it means that some of these other bodies are not dead. They're not just like cold places. Volcanoes are a sign of like activity, and activity means heat, and the heat maybe means life. It's exciting to see other places in the solar system where stuff is still happening. And so currently in the solar system, of course, we have volcanoes on Earth. And then there's three other places where we've seen this kind of activity.

And they're all moons. There's a moon of Neptune, which is called Triton. There's Enceladus, which sounds like a salad, but it's actually the sixth largest moon of Saturn. And then, of course, there's Io. Did you just call it insalata? Because that is literally the Spanish word for salad. I was trying to figure out how to pronounce it. I think it's insaladas, isn't it?

Is it anceladus? Enceladus? Well, I think I'd like a Caesar insoletus, please. Well, we'll get that to you straight from Saturn. But wait, so most of the volcanoes we know about that are active now are in, moons? There aren't any in like, you know, Venus or Mars or Mercury. None of those places have active volcanoes. You know, Mars we think has some activity going on. Like there are Mars quakes, but there are no volcanoes left on Mars. And of course, there's this fossil of a volcano,

Olympus Mons. It's the largest mountain in the solar system, but it's not currently any more a volcano. There's nothing happen in there. I guess what makes us special then here on Earth? What is it about Earth that lets us still have volcanoes? That's not something. we really understand. Like we don't understand the inside of Venus and Mars or Mercury. It's something we're still studying. It's a difficult thing to do. And in fact, we're going to have a whole podcast about whether Mars and Venus still have liquid cores and what's going on with them. But it's not something that's easy to understand. There's a lot of discussion and debate. Really? We don't know. Could it just be luck? Or is it something about our crust, you know, like our composition of the rock

or our atmosphere? It's something to do with the size, right? The size of a planet determines like how hot it gets, how much gravity there is, and also how long it takes to cool. So, for example, Mars is much smaller than Earth, which is probably why it's cooled faster and the outer crust has formed and been so thick and choked off all of those volcanoes. But also, you're right, volcanoes are important. They're a big part of, like, why we have our atmosphere. And so it's interesting to learn all about this because it helps us understand, like, for other planets and other solar systems, are they likely to have volcanic activity, which could produce the atmosphere they need to eventually seed life.

Oh, you need volcanoes to make an atmosphere, right? You don't just get it for free. You don't just get it for free. Like, if there was gas around when the Earth formed and mostly got blown off, because you didn't have like the steady currents you need to have a magnetic field as early on. So by the time things settled down and cooled off and you had like a nice magnetic field to protect your atmosphere, then you need to sort of replenish it. The same way like Earth once had water when it was very, very young in the formation,

but most of that boiled off into space and it needed to be replenished, mostly by comets and other things. In the same way, we need to replenish our atmosphere, and that mostly came, I think, from volcanoes. I see. And I guess gas planets can have volcanoes, which is, or ice planets, right? They're too cold?

You can actually have volcanoes on ice planets. What? Like ice lava? Yeah, but they are cryovolcanoes. They do not blow out like molten rock. And that's what we think is going on, for example, on Triton. We think solar radiation penetrates the surface and heats up some layers that are below that are darker,

So they absorb more of this energy and they get hot and then they blow out through the surface. Well, what do they blow if not lava? It's mostly like nitrogen gas or some water vapor or methane or CO2. Some of these things are called cryovolcanoes because they're still really cold. But it's still like pressurized gas. So it might still be hot, no? It's pressurized gas, but it's like, you know, liquid nitrogen is still really cold. And so if you're blowing out liquid nitrogen into space and it's not going to warm you up,

Oh my God, a liquid nitrogen volcano, like a volcano that's not red, but like blue or white, right? Yeah, absolutely. This is a pretty exciting moment when they found it. Like Voyager 2 saw this on Triton in 1989. Pretty exciting moment to like see this. And it rises up like five miles into space because this thing has very light gravity. And so you don't get like, you know, bubbling up a volcano like you do on Earth. These geysers just like shoot out into space.

Wow, it was so exciting. The astrophysicists cried. And that's why they call it a cryo volcano. That joke makes me cry. That's what I'm here for. So I feel like you can't call it a volcano if it's not lava. Shouldn't there be another name? Yeah, well, they do have another name.

They call it a cryo volcano. It's a cold volcano. It's a frozen volcano. Oh, I see. They get a derivative name. Yeah, sort of. And this thing happens in other places. So like in salatus or in saladis, the moon of salads has the same kind of thing.

It shoots up icy particles. and Cassini in 2005 went by and it took pictures and it actually flew through some of these jets because they come from the poles and so they're pretty reliable, you know where they are. And it measured it has water vapor and nitrogen and methane and carbon dioxide and stuff like that. And a surprising amount of ranch dressing, which is weird.

Too much ranch dressing. Everybody always overdoes the ranch dressing. More croutons, less dressing. And we talked once about the Moon Europa, which is a cool place that has like an icy crust, probably with water underneath, like a big water ocean. And sometimes that cracks. And you get these geysers of frozen water vapor plumes that come out, you know,

that might, for example, have little microbes in them. So we're sending a mission to Europa to sample these geysers. And, you know, can you call them geysers? Can you call them volcanoes? You know, I don't know. Cryo geysers. Cryo, geysers. Yeah, exactly.

But there is one that you can definitely call a volcano and is very impressive. And this is a volcano that's on the moon. Iyo. That's a moon of Jupiter? Yeah, Iyo is a moon of Jupiter. It's the innermost moon of Jupiter. Okay, so this one actually has like lava in it. Yes, this is the most volcanically active body in the entire solar system. They've seen like 150 different volcanoes. They think there's even more like maybe up to 400 or so. And this thing is really hot because it's so close to Jupiter. Jupiter's like tugging on it and it's

basically squeezing it. Remember we talked about like tidal forces. What happens if you get really close to a black hole? It's going to pull on one side of you more than the other side of you. Well, that happens anytime you get close to any large body. For example, the moon is doing that to Earth and like squeezing the water on the earth, which is why we have tides. It's like the gravity is kneading it, right? Like it's sort of like stretching it and compressing it and that creates heat. That warms it up.

Exactly. It creates friction internally and that keeps it hot on the inside. So Iowa is hot because Jupiter is like kneading it with its gravity. Boy, this just got a little racy here. Racy and spacey Racy at a distance And so it melts the rock Inside I-O and you have like

actual lava And you have these really huge eruptions The New Horizon spacecraft saw one eruption From this Tvajstar volcano That went up 180 miles high This is like actual lava Actual lava shot out into space Yeah 180 miles

We don't get that kind of activity here on Earth Do we? Like the most we get is a couple of miles Yeah exactly And of course because we have much more gravity, right? So it's easier to launch like tens of cubic miles of hot lava up into space when you're a smaller moon that just isn't as much gravity. It sounds like it has fear volcanoes in Earth, right? We have millions, you said, underwater maybe? We have millions, yeah. Yeah, but these seem more powerful, like more dramatic. And it's a denser volcanic environment. There's

like more volcanoes per square, you know, kilometer or something. And Io also features what one geologist is called in their paper, the most powerful volcano in the solar system. Oh, wow. There was a competition, and he gave the medal to this one. What's it called? It's called Loki. It's named after, you know, the trickster god of North mythology. People think it's the most powerful volcano in the solar system.

It's 700 times more powerful than Kilauea, for example. It puts out 700 times as much lava every year. Wow. That's a lot of lava. It's a lot of lava. That's like harder than Tom Hittleston. Yeah, exactly. It'll burn you.

And it's hard to measure these things. You know, like, we don't have, like, great cameras taking pictures of this stuff. What they can do is sort of just watch in the infrared these eruptions of heat. You know, they watch the heat on the surface and they try to convert that heat measurement into, like, a volume of magma. So, you know, there's uncertainties there, but these are definitely big, powerful things hanging out in the surface of IO. You said we can look at it from here. Like, you can actually see the heat and the signature. Or do you need to get up close?

And have we taken pictures of it? We have taken pictures. We have had like flybys taking pictures of these things. So you can see it. But the best shots we have come from watching it steadily day by day. And you can use like space telescopes. So like Hubble has imaged it, for example. It's a weird volcano because it's constantly leaking lava.

But it also tends to erupt. So like every 540 days, there's like a huge outpouring of lava. And then it just sort of bubbles around for a while leaking lava. All right. So then that's our winner. That's the most part. volcano in the solar system. It's Loki in the moon Io, which is a moon of Jupiter.

Yeah, and I want to thank Robert Howell, a geologist, University of Wyoming, for answering all of my questions about volcanoes. And he wanted me to point out that Loki is not really a shield volcano because the weird composition and the low gravity, the lava that comes out doesn't like really build up into a shield. He called it a patera because it's like this vast pool of lava. So if you look down onto it from space, it's just this like lake of lava. but they don't even really understand exactly how it forms.

Interesting. It has a gravity assist kind of. Like there's less gravity there so that maybe you can shoot higher. Yeah, it shoots higher and it doesn't build up the same way. So like the shape of the volcano, the whole nature of it, you can't even really call it a shield volcano because to be a shield volcano requires basically being on Earth or having a similar gravitational environment. Like the whole shape of it is different then, huh?

The dynamics of it, I imagine. Exactly. Pretty cool. All right. So that's the biggest, most powerful volcano in the solar system. system, it's 700 times more powerful than Kilauea. Yeah, it's pretty impressive. I would not recommend Io as a family vacation destination.

Hawaii is much better. Well, you just don't go when it's erupting, but you know, you have a 500-year window there. You can swoop in and take pictures. All right, we'll send you there. You can go touch the lava. Yeah. I'm sure I'll love it. Stop by for a salad on the way.

A warm salad. All right. Well, we hope you enjoyed that. And think about all of the amazing things that are out there in other planets, other moons, things that we think are big and powerful here are maybe pale in comparison to things that are right in our neighborhood. And that's why we love to throw our minds out there into the rest of the universe to imagine how life here on Earth is different or similar to what's going on out there in the rest of the universe. When aliens come, can we talk to them about volcanoes

or will they be amazed that we have these crazy bubbling pots of lava on the surface of our planet? Interesting. We could become like a tourist destination. We are the Hawaii of the galaxy. There you go. We're the taco stand of the solar system. All right, well, we hope you enjoyed that. Thanks for joining us. See you next time. Thanks for listening.

And remember that Daniel and Jorge Explain the Universe is a production of IHeartRadio. For more podcasts from IHeartRadio, visit the IHeartRadio app, Apple Podcasts, or wherever you listen to your favorite shows. December 29th, 1975, LaGuardia Airport. The holiday rush, parents hauling luggage, kids gripping their new Christmas toys. Then, everything changed.

There's been a bombing at the TWA terminal. Just a chaotic, chaotic, chaotic scene. in its wake a new kind of enemy emerged terrorism listen to the new season of law and order criminal justice system on the iHeart radio app apple podcasts or wherever you get your podcasts my boyfriend's professor is way too friendly and now i'm seriously suspicious wait a minute sam maybe her boyfriend's just looking for extra credit well dakota luckily it's back to school week on the okay story time podcast so we'll find out soon this person writes my boyfriend's been hanging out with his young professor a lot. He doesn't think it's a problem, but I don't trust her. Now he's insisting we get to know each other, but I just want her gone. Hold up.

Isn't that against school policy? That seems inappropriate. Maybe find out how it ends by listening to the OK Storytime podcast and the IHeart Radio app, Apple Podcasts, or wherever you get your podcasts. Get fired up, y'all. Season two of Good Game with Sarah Spain is underway. We just welcomed one of my favorite people, an incomparable soccer icon, Megan Rapino to the show and we had a blast. Take a listen. Sue and I were like riding the lime

bikes the other day and we're like, we're like people ride bikes because it's fun. We got more incredible guests like Megan in store plus news of the day and more. So make sure you listen to Good Game with Sarah Spain on the IHeartRadio app, Apple Podcasts, or wherever you get your podcasts. Brought to you by Novartis, founding partner of IHeart Women's Sports Network. This is an IHeart Podcasts.