StarTalk Radio - Cosmic Queries – Starquakes with Conny Aerts

Episode Date: October 11, 2022

What is a starquake? On this episode, Neil deGrasse Tyson and comic co-host Matt Kirshen explore asteroseismology, the sun, and what’s happening on the insides of stars with astrophysicist Conny Aerts. NOTE: StarTalk+ Patrons can listen to this entire episode commercial-free.Thanks to our Patrons Zoran Nesic, Sarah Rina Rosen, and Joshua Brewer for supporting us this week. Subscribe to SiriusXM Podcasts+ on Apple Podcasts to listen to new episodes ad-free and a whole week early.

Welcome to StarTalk, your place in the universe where science and pop culture collide. StarTalk begins right now. This is StarTalk Cosmic Queries Edition. This one is titled Starquakes. I've got as a co-host here Matt Kirshen. Matt, welcome back to StarTalk. Thank you so much for having me. It's nice to be back. Yeah, so you solicited questions about like stars and starquakes from...

I'm very excited about this topic and so are the listeners. There's been a lot of... A lot of your Patreon patrons have responded to this one. We're going to try and get through as many of these as possible, but... Well, I don't know a damn thing about... I will try. I don't know a damn thing about starquakes so yeah i know i live in california where earthquakes are a problem so i know how to deal with those but i don't if you're involved in a starquake do you it's getting under a table still enough or how do

we yeah we're gonna we're gonna find out for sure so guest, with the expertise we need, is Connie Aerts. I think I pronounced that right. Connie, welcome to StarTalk. Hi. Glad to be here. Excellent. Now, you're in from Belgium and the Netherlands. You have a dual appointment, one as the professor of astrophysics at, let me get this straight, In Leuven, Belgium, and it's KU, Catholic University in Leuven, is that correct? Yeah, KU Leuven. Just don't worry about it. KU Leuven. Leuven is a small college town in Belgium, so that's where I'm from. Excellent. And in the Netherlands, you're a professor of astro seismology at Radboud University in the Netherlands. And so the fact that that's even

a title to hold, astro seismology, it says how far we've come in just the specification within the broader field of astrophysics. And I think this is just delightful. And your expertise is stellar astrophysics, stellar structure and evolution. These are two favorites of mine professionally. But I never really thought about seismology in anything other than Earth. And so first tell us, what is astroseismology? Well, it's the study of the seismology of stars. Now, as you say...

You're going to have to do better than that. Yeah, I know, I know. Give me a chance, right? Give me a chance. So, we all know earthquakes, that the Earth has a whole crust, you know. It's not pleasant to have earthquakes, but it's fantastic to have starquakes. Stars are hot caches spheres, and they also move up and down. And we can use these starquakes to learn what's inside the star.

It's the only way to know how to look inside a star. And that's just like seismologists of the Earth. They are the only happy people when the Earth is quaking, let's say. Why? Because the earthquakes create waves. They travel into the planet. They bounce back at the iron core and seismographs detect it. And then we can do all sorts of fun physics and chemistry of our planet. And we do the same, but then for stars. Okay, Matt, I think Connie just said that while cities are burning and everyone is dying,

geologists are delighted that they have earthquakes. Absolutely, yeah. I'm hiding under a table while my pets are going crazy and seismologists are like, the data, what beautiful data we're getting right now. The data. So, but I'm confused though, because when I think of an earthquake, I have a very simple understanding of it, that you have a rigid crust that is under pressure and under tension, and then it spontaneously gives way.

And then you get an abrupt shift and that's an earthquake. But when I think of stars, they're fluids, they're gaseous fluids. So what could possibly be quaking if you don't have anything solid to build up the tension that then gets released? Yeah, so that's a bit different because the star quakes are happening all the time because it's a gas. And so you have motions, right? Up and down motions, but also more complex motions.

And if you press a gas and then release it, it creates sound waves. That's a bit like music in a theater hall. So for me, stars are three-dimensional musical halls, concert halls. And so the nice thing is that starquakes are always there. Luckily for us humans, the earthquakes die out quickly, right? And they're rare, relative. I mean, they're rare in the sense of the ones that do serious damage are rare. But as I understand it, there are actually earthquakes of even very small magnitude almost all the time. I think that's correct. Yeah, that's correct, because anybody in nature vibrates.

And so, yeah, stars do that all the time, and they do it permanently, which for us astrophysicists is great, because we can measure the up and down motion. Why? Because it gives changes in the temperature of the star. And so the brightness of the star changes as a function of time. And then we have our seismographs that measure these changes as a function of time. And your seismographs are also, you implied there, that they're sensitive to those boundaries where temperature changes. That's right.

Because your sound would get reflected, or your pressure wave, which we're calling sound, would get reflected or bent in a different way. And you use that to model the total interior structure of the star. Is that correct? Yeah, that's correct. But yeah, like we cannot hear these sound waves with our ears. So we see the brightness variations because the sound is only propagating there where there is gas. And between us and the star, you know, there's nothing.

It's empty, right? So we can't literally hear the frequencies of the waves, but we see the up and down motion. And so that is actually connected. The frequency of the sound waves created by these up and down motions is connected to the physics and also the chemical composition of the star in its interior. So we can't literally dive into the stellar concert hall, but we can measure the frequencies from a distance, let's say. But if you could, you would hear all of these. Yeah, yeah, yeah. That's fantastic. Sometimes I give lectures for musical artists, and then they are all totally fascinated about these sounds. Let me test this on Matt. So Matt, NASA is going

to plan a mission to send astronauts to the sun to listen to these sounds. But it's dangerous, obviously. So they're going to go at night. That, by the way, I know we haven't got into the questions yet, but that actually is one of our questions from Lucas, from listening to Lucas, was actually about whether you can make that, the heartbeat of stars into music. Yes. So you're saying yes, that you can absolutely do that. Oh, my goodness.

So have people done, so you have a portfolio of frequencies going on at different times in different locations, and so you get a clever musician to sort of take all of that base material and figure out a way to listen to it. That would be interesting. Yeah, yeah. So we actually just shift.

I mean, each star has its own symphony, right? Depending on how big it is, how much mass it has, how old it is, it has its own symphony. But then we shift that global symphony into the audible range of humans. That's called sonification. It's a whole field by itself. And actually, it allows blind people to be astronomers. I find that I'm a very, for me, inclusion is very important.

So in this way, we can reach people who can't see, but they can hear the stars. But we have to help them a little bit by shifting to the audible range. We have finally achieved the goals of the ancients by celebrating the music of the spheres. Yeah, exactly. That's true. Oh, man. Okay. So that question already got asked, Matt.

So who asked that? That was Lucas from New West who asked that question. What is New West? What is that? I don't know. It just says New West. I'm not sure exactly. But Lucas also proceeds it by saying, I have a geek kind of question, which I don't think you need to proceed any questions to start off with that. Oh, this is a geek safe space here, everybody. You don't have to preface it.

But New West, I mean, I live in New York. And, you know, there's... Formerly New Amsterdam. Just south of New England. I'd have never heard of New West. I don't know what that is. Maybe that's California after it breaks away from the San Andreas Fault. Just floating off.

Just floating off into the Pacific. So why don't we get some more questions here? This is great. Now that we have some foundation for what... Yeah, we've got some awesome ones. Some of them have already... Some of them you've already kind of answered, and I'm sure that'll happen as we go along.

But I'll try and get as many ones in. So James Smith from Indianapolis says, what is the largest recorded quake not found here on Earth? And also, do all planets have plates that shift like Earth? A couple of people have asked that question as well, whether all other planets have plates. So let's start there first. We know Earth is geologically

active because there's like volcanoes and plate tectonics. So where else in the solar system might do that before we get back to the sun? Oh, well, all planets will have quakes. I mean, any body in nature quakes. I was banging,

I was about to bang the table here, but I will not do that. But the table would also have, you know, quakes. So they then pile quickly depending on whether you have a gaseous planet or a crust-like planet like Earth. So Jupiter, Saturn, all the big gaseous planets in our solar system, they also have quakes. Wait a minute, Connie. You're saying every sound anywhere is a quake to you. Yeah. Okay.

That's true. You do. So a guitarist, what we're doing right now is kind of causing the tiniest of tiniest quakes by making sound. We're quaking the Earth's atmosphere. Of course. You're creating sound waves.

Oh, my gosh. Listener Woody also asked, by the way, on this same topic, would the ice giants experience quakes? I guess you've said the answer is yes. And what possible differences would there be between Earth, water, ice, frozen, methane, and nitrogen quakes? Yeah, so the… Right, that's a bit.

Wait, just a quick thing. So we've got ice in Uranus-Neptune, the ice giants, and we've got sort of gases in Jupiter-Saturn. We've got Earth's crust here. And so presumably, Connie, you've got some portfolio of who makes what kind of sound under what conditions so that you can decode what you hear. Is that correct? That's correct. And so the frequency of the sound waves of all these heavenly bodies is really determined by the density of the object, right? And so stars are gases and their

density is very different from the density here on Earth. Very low, yeah. Or in Jupiter, yeah? So by measuring the frequencies of the quakes, we know quite directly how big the object is and what its density is. And if you know these two, then you know the mass. So that's the basic tools, right?

You said that on the sun, you measure the quakes because some parts of the sun get brighter relative to others because they're hotter. How do you do that with just a planet sitting out there in space? Yeah, we need to send some space mission there to come closer and to be able to see this. And so for stars, we also, I mean, this is a booming research field in astrophysics. Why? Because we recently had the luck of being able

to measure the brightness variations with satellites. We don't have a seismograph that we can put there, literally, like for the Earth, but we sent instruments that measure these tiny variations in the gas, you know? Okay, so I'm an old-world astrophysicist, so when you say we make these measurements by going there, that's cheating. That's cheating, yeah, yeah.

We can't go there. That's tabletop science at that level. Yes, yes. If you get to go there. Yeah. But you're saying it's the same kind of features in a gaseous planet. Some parts will be a little warmer or cooler than others on the surface, and that'll tell you, that'll give you seismic information about what's going on inside.

Yeah, as soon as the density changes, for whatever reason, density changes give pressure waves and these are sound waves. Right? Okay. And so the follow-up part from James, what's the largest recorded quake not found on Earth?

Oh, we have the slowest quake in a star. It can take several, several months in period. Well, for the sun, it's five minutes, by the way. For those who don't know, the solar quakes go up and down, create sound waves with periods of about a few minutes, five minutes at their strongest. So for a very big blue supergiant star, it takes months before the quake went up and down. So just to be clear, the normal frequencies we listen to are hundreds and thousands of cycles per second. And that's what our eardrum and brain will record. And you're saying these are cycles every five minutes. Yes, and that's even fast. Or even every month. So that's why you have to shift it

to our audio range. Otherwise, we would never even know it was happening. That's right. These are slow waves to human standards. Right. You'd vaporize first, but while you're vaporizing, you would not know you're in the middle of a starquake. That's right. That's wild for me.

So, incredibly slow, but presumably hugely energetic. Yes, that's true. That's wild for me. So incredibly slow, but presumably hugely energetic. Yes, that's true. So the energy of each wave can be quite tremendous, but that also depends on the type of waves that you're dealing with. Okay. Wow. All right.

Well, let's take a quick break, and we're to come back to more starquakes. Something was like, what? But to Connie, everything's a quake. So we'll get more into that in this episode of StarTalk Cosmic Queries when we return. I'm Joel Cherico, and I make pottery. You can see my pottery on my website, CosmicMugs.com. Cosmic Mugs, art that lets you taste the universe every day. And I support StarTalk on Patreon.

This is StarTalk with Neil deGrasse Tyson. We're back. StarTalk Cosmic Queries. We're talking about star quakes. And my co-host, Matt Kirshen. Matt, where can I find you on the internet? Well, you can find my podcast, Probably Science. I start with the Neil episode. That's always a nice place to start. I was a guest my podcast, Probably Science. I start with the Neil episode. That's always a nice place to start.

I was a guest once on your Probably Science. I just thought by now it would have been called Certainly Science. I just thought it was evolutionary, but apparently not. The longer we do the show, the more probably it gets. It's going to descend through possibly to... To probably not. And then I'm on Twitter, at Matt Kirshen, and technically on Instagram, but I'm very rarely there. Okay, Kirshen, K-I-R-S-H-E-N.

And we have as our in-house expert right now on Starquakes, professor of astro-seismology in the Netherlands. But right now, Connie Aerts, I think I pronounced that right. Is visiting New York city at a place called the flat iron Institute, uh, which is in the flat iron section of Manhattan and very cool science is happening there. All manner of science. It started with sort of math and astrophysics, but it's, it's spilling into biology

and computer science, where very deep problems that need high-performance computing and clever people to solve them are invited to then gather their talents and try to solve the secrets of the universe. And Connie Arts is on sabbatical this year. So, Connie, we're delighted to have you as part of this podcast. Very grateful to be here. Thank you. Yeah, yeah. So we've got some more questions.

But before we do that, I just want to be clear that most people's understanding of the word quake is, I think, built in is that it's abrupt and short-lived. That's kind of built into our life experience with a quake. But we're now hearing about quakes on completely different time scales. Should you have invented another word to describe a quake that moves on the scale of days or months rather than seconds or minutes? Sure. And I use the term star quakes for popular lectures. But actually in our professional life, we speak of stellar oscillations. So they're global oscillations.

They're smooth. They're properly behaved. So for stars, it's a bit less abrupt than for earthquakes, let's say. Okay. Okay. So if on Earth they were Earth oscillations, then Matt, maybe you wouldn't have to hide under a desk or in the structural beams of the house. I would just ride it out. Just ride it out?

Surf it out. You surf it out. Keep the knees perplexed. Keep your core stable. That's all you need. But you would get seasick all the time, you know, because they would always be there, you know. Yeah.

Lies on the horizon. That's the secret. Always look out the window. Don't try to look at fixed objects inside. Take me surfing one day out in Los Angeles and teach me. Oh, I'm a terrible surfer. Oh, okay. So Matt, what else do we have for Connie? We've got some great questions.

By the way, just a side note, I love when we have topics like this, when it's something that is close to Neil's wheelhouse, but just outside it. When it's like in your field of astrophysics, but something that you've never really encountered. They're my favorite episodes. Because you like looking at how much of an idiot I am. That's what you're saying.

I love it when you're just at the edge of Neil's knowledge. It's my favorite episodes. Because you like looking how much of an idiot I am. That's what you're saying. I love it when you're just at the edge of Neil's knowledge. It's my favorite. It's the best. Well, those are my favorite episodes where I learn stuff. Absolutely. This is good. So I'm going to combine these two questions. I like to do this because two people.

I want to hear their names anyway. Absolutely. do this because uh because i want to hear their names anyway absolutely dylan and from nau in flagstaff and alejandro reynoso from monterey have both asked about what we can actually learn from the oscillation of stars dylan says can we predict its age and or understand the core and also do all stars oscillate or just dying stars supermassive stars main sequence stars and then alejandro says what have you learned from analyzing starquakes that you couldn't learn with other methods so basically they're both asking what specifically is it that we can learn from these quakes

I'm going to tighten that question and say what are you learning that we didn't otherwise figure out through other means if there's one word that I have to ask to that question it is rotation of stars that's more than one word that I have to ask to that question, it is rotation of stars.

That's more than one word, but internal rotation of stars. You know, and why is that? Let me give the analogy with music again. So we have sound waves that are happening inside a star, but the gas in the star is rotating around, right? And what do you get when you put a musician in a theater play and you make the podium rotate just for the fun of it as a surprise to the musician? You get pissed off musicians. That's what you get.

Exactly. I like that experiment, actually. You can really hear that. But the symphony is destroyed. That's what the audience would say. Now, for me, as an astro-seismologist, the frequencies of the waves get shifted, right? The Doppler shift. Yeah, they get shifted because of the extra motion due to the rotation. And we can measure that.

And we're not measuring that at the surface of the star, but inside the star where the starquake has its strongest energy, right? And so what we have come to realize is that the theory of how stars evolve, relying on how they rotate in their interior, is quite off. It's not very good. And that's not surprising, right? Because we could only measure, before we had starquakes, we could only measure the rotation

of the star at its external layer. Like for the Sun, you see the tiny little dark spots of the Sun rotating around, if you're patient? Every 26 days you see them back in your line of sight. So the Sun rotates with a period of about 26 days, but that's just the outer layers. It doesn't say at all how it rotates in its interior. So if you have no information, what can you do? Well, you think, well, it won't be that different.

You just assume it's the same, right? You assume it's the same. I mean, everything else rotates as a kind of a unified object. Why would I even think some lower level would rotate at a different rate? Well, the stars have many more surprises than us astrophysicists have imagination. What a smack! Oh, did you hear? Matt, did I just hear this woman correctly here? Yeah, I stand by it. I'm on team star on this one. That was a smackdown right there. Yes, I always say the stars are right, the theory is wrong if it doesn't match with

each other, right? Uh-huh. So thanks to the frequency shifts of these waves, we can now measure how stars rotate around. And why is that important? Well, if they rotate faster or slower, then their material gets mixed in a different way. Yeah. That's also something you can imagine if you take the analogy with coffee drinkers. You know, if you if you like coffee with milk, you pour milk into your coffee

and you don't wait until, you know, until everything is mixed because then the coffee is cold and it doesn't taste well anymore no you take a spoon and you rotate your coffee in my terminology that is saying you bring angular momentum to the coffee cup and what why do you do that that's what everyone says when they're having coffee that's what everybody does without saying it. And that's because everybody prefers well-mixed coffee with milk. I'm assuming at the Flatiron Institute that just the coffee station there has angular momentum implements. Yes. How much angular momentum would you like on your coffee this morning? Do you want a metal angular momentum implement or one of the wooden straight ones?

Well, we could do an experiment of how people do that. Do you want a metal angular momentum implement or one of the wooden straight ones? Well, we could do an experiment of how people do that. But, you know, the diversity of human beings taking their spoons will be large. And in stars, there's a whole range of internal rotation frequencies that we have measured. We have about 2,000 stars now for which this has been measured by many groups in the world with astro-seismologists. And so the life of the stars is really going slower, if I look at the measurements. You mean our estimates for their life expectancy

need to be updated to have them live longer than we originally thought. Is that what you're saying? Yeah, particularly for the big, massive stars. Is that because they're mixing more material into their core? Yeah, they're mixing, yeah. Giving them a little more lease on life? Yeah, and they get more material into their inner part.

And in the inner part of the stars is actually a nuclear reactor for me because the simplest constituent, which is hydrogen, is turned into helium by nuclear fusion. Stars are masterpieces in that. But if you bring more hydrogen into that area where it's hot and dense enough, then the star can live longer. And so the rotation affects how much nuclear fuel you bring inside its interior, actually. That was about to be the opposite of what I would have guessed, because I was wondering whether the sort of the stirring effect

would have sped up the fusion reaction by kind of, you know, you can increase the speed of a chemical reaction. I know that's different from a nuclear reaction by stirring the chemicals together or by increasing the energy in there. But you're saying it's the opposite because it's bringing more fuel in from the outside layers of the star. Yeah, so once the nuclear burning is ongoing, the nuclear fusion in stars is stable. Stars can do that very well.

We humans can't do that here. Now, everything I know about the nuclear furnace says that it's pretty small relative to the size of the star itself. Do your waves give you enough information about tiny areas like the nuclear core? Yeah, well, tiny. It's 10% of the mass that typically takes part in the nuclear fusion. So it's still 10%. Of the mass.

Even if it's physically small, it's got a lot of mass going on. Yeah, because the density is very high. And so if you change that 10% to, say, 12%, that sounds like, you know, it's only 2%, you know. But that's a lot of fuel that you bring into your nuclear reactor. Right. And increase the life by at least 20%, perhaps. Yeah, yeah, yeah. Or you think maybe.

Yeah. Yeah. It can really change the lifetime of the star. So that's, that's, so to come back- And Matt, if you were in the center of a star, you'd be dense too. I just wanted to tell you that. Oh, thanks. It's one of the nicest things anyone's ever said to me.

We've got more questions, Matt. Bring them on. We do. Aziz from Saudi Arabia says, I wonder if it's possible for a star to have a starquake so strong caused by, for example, nuclear fission or fusion happening abnormally fast or caused by any other reason to lose mass? I thought I'd ask that one because we're already talking about fusion. You know, in the formation of stars in the galaxy, you can get shockwaves across a gas cloud that's otherwise mining its own business and it can trigger gravitational collapse and other interesting features so i'd love that question connie so are starquakes just the product of what's going on or are they a participant in causing what's going on yeah so you can have

all sorts of cause reasons why stars have these oscillations, right? And they can indeed be caused by the fierce turbulence in the core of a very massive star because it's, you know, we call that convection, turbulent motions, and they create waves also because, again, they make the gas,

you know, compress and expand. But there are also other reasons why stars can have starquakes. Think of the Earth-Moon system and tides. Well, half of the stars, or even more if you go to higher masses, they live together with two. And then they have tidal forces. Binary star system. Just like in that scene in Star Wars

where Luke comes out, is it the sand planet? And he sees a double sunset. That's the only accurate science in the entire series. That's okay. That's okay. You know. Yeah. Okay.

So what happens there? So you have a gravitational tidal dance. That's right. They rotate around each other and they pull. They give a tidal pull. Right? They rotate around each other and they pull. They give a tidal pull, right? And so you could also say that, you know, for me, tidal forces are actually forced oscillation. You know, I say everybody oscillates in nature.

So when the stars are close enough together, the tidal oscillations, as I call them, are very strong, can be very strong. So that's another reason why stars can have star flakes. So these are like a tidal bulge in the direction of the object responsible for it. Yeah. See, in my older years, I have a tidal bulge as well. I'm watching for that just to see what I can do about it. Yeah. You want to prevent it, but we like it when it's really started.

Alright, Matt, give me some more. Quentin from Switzerland says, and I don't know what Quentin's referring to, so hopefully one of you two can fill me in, says, do you need more data to exactly figure out what happened with Betelgeuse recently? Is it pronounced Betelgeuse? Betelgeuse? Betelgeuse, yes. Is it pronounced Betelgeuse, Betelgeuse?

Betelgeuse, yes. It is pronounced Betelgeuse, like the film, but spelled differently. It seems pretty unlikely that we will witness a similar event in the near future. So what did happen? I got to lead off with this, and then we'll get the actual answer from Connie. I heard Betelgeuse is one of the brightest stars in the night sky. It's an important star in one of the most dominant constellations of all 88, dominant in size and appearance, is Orion. Orion is visible in both the northern and southern hemispheres because it straddles the equator on the sky. And so there's this star, Betelgeuse,

one of the biggest, baddest red giants in the known universe. And someone told me, do you realize Betelgeuse is getting dimmer? I said, no. What? What? And I looked up and I went, it was, because my whole life Betelgeuse was a certain brightness relative to other stars in the constellation. I cannot communicate to you my loss of breath in the moment I looked up and I say,

what is happening? Is this, you know, is this, is the seventh seal broken? Is there something biblical? So I want you to know, I nearly freaked out. So what happened to Betelgeuse a year ago when it just got mysteriously dim?

Like it was, went to less than half its normal brightness and that had never been observed ever in any time anybody's been looking at the star. So we're going to blame you for this. What happened? Well, Betelgeuse is behaving normally at the star. It's, you know, it's a super giant, right? It's a very big star. And so these you know, it's a supergiant, right? It's a very big star.

And so these stars are nearing the end of their life. And so they're puffing up their material and they're blowing it away, so to speak, right? And so when material gets lost from the star, well, then for us, the star is obscured because it's in between the supergiant and us. There's material that is being expelled. Now, for me as an astro-seismologist, that's a bit annoying, that behavior, because Betelgeuse has starquakes, but all that material that's being expelled makes it hard to still measure them. It's blocking your view. It's blocking the view. And that's also the reason why, for us, it's difficult to do astro-seismology from ground-based telescopes.

The stars are up there. People say they twinkle, right? But that twinkling that you see with your eyes, that's not the star. That's actually the starlight that is being perturbed by the Earth's atmosphere. Right. And so it's a bit similar, but then the twinkling of Betelgeuse is caused by the material it has expelled. But it does have also oscillations. And these oscillations can tell us how old it is and how big it is, etc. All right. It's Betelgeuse ready to blow because we think that's a supernova category star.

Yeah. I said, oh, my gosh,elgeuse ready to blow, because we think that's a supernova category star. I said, oh my gosh, something bad is going to happen. It's going to happen. It's not bad. No, it's not bad, because it will explode eventually, but that can take still some while. So, you know, you don't want to go and look every day, because you may need to have some patience. Connie, we're trained to think that if something blows up, it's bad. Okay, I'm sorry.

Yeah, but these guys are like, it's exciting. This is more data. It's more data. Okay, all right. This is like the rocket launchers who the rocket blows up on the launch pad. You say, oh, are you upset by that failure? No, that was an experiment rich in data. Yeah. oh, are you upset by that failure?

No, that was an experiment rich in data. Yeah. Well, but I'm saying it's good because it enriches the galaxy with metals, with carbon, with oxygen, with iron. And, you know, we need that as human beings. Okay, just to be clear, Matt, astrophysicists are uh we are very lazy with regard to the periodic table of elements and so any element that's not hydrogen or helium we call it a metal but this freaks out chemists we're self-aware of this bad vernacular but the point is 98% of the universe is hydrogen and helium

and the rest is just other stuff. It's just the experimental era. So we just call them metals and I'm just covering Connie's ass right here when she said the metals such as carbon. She's being fully astrophysical in the referencing. astrophysical in the referencing. But Connie, you speak of this blockage of ejected gas. Of course it would do that.

Yet it hasn't done it in the thousands of years we've been observing the night sky and mapping its brightness relative to other stars. So do you have an account for why it's doing it now and it's not doing it regularly? Oh, but you see, we astrophysicists have to be very patient because the time scales, when for stars to do this kind of stuff, you know, that's like hundreds of thousands of years, you know, and- Okay, so you're saying if we'd see it only once in a few thousand years, that could be a regular interval.

Yeah, yeah. Okay. All right, she got out of that one, Matt, I think. It's just annoying that we human beings only live for like 100 years, if we are lucky. Yeah, we're very lucky. In an astronomical timescale that's instantaneous, that's very, very lucky. So that's, in an astronomical timescale, that's instantaneous. That's very, very short. Yeah.

All right, we've got to take our last break. And when we come back, more astro-seismology with a professor of astro-seismology, Connie Arts, on StarTalk Cosmic Queries, the astro-seismology edition. With our expert, a professor of astro-seismology, Connie Arts, and she's on sabbatical now at the Flatiron Institute in New York City, which has gathered all manner of computational scientists in multiple fields where they not only compare notes with each other in their own field, but across disciplines,

perhaps there's some cross-pollination that can lead to discoveries that wouldn't otherwise happen. And Connie, you are based in the Netherlands and in Belgium. You have two different appointments that, of course, there's strong overlap in what they are, but this is very cool that we have you here. We're borrowing you from Europe and great to have you here in my hometown, New York City. So, Matt, we have a few minutes for a few more questions. Let's see how many more we can slip in. These questions are from our Patreon members still, correct?

They are, yeah. So, Kevin the Sommelier asks, does astro-seismology coincide with the data we can get from the James Webb Space Telescope? Are we able to see those quakes in infrared? Ooh, I like that. Yeah, and also then gives a wine recommendation. Oh, yeah, because I told him I would not allow him to ask another question. If he's going to bill himself as a sommelier,

there's got to be a recommendation. So he recommends specifically for our Belgian guest, it says, with Mouffrit, Kevin recommends a bottle of Muscadet Sur-le-Lagrange. So there we go. Thank you, Kevin, for that. Okay. That sounds like a dessert wine. All right. Let the world know. Okay. That's a recommendation.

So I love that question, Connie. I didn't even think to think about this because I love Stellar Evolution, but I'm primarily a galaxies guy and a large-scale structure guy, which the James Webb telescope is exquisitely tuned to observe the early universe. And it would never occur to me to imagine if it could be of use to you in thinking about starquakes. So how has your field put your sort of hooks into the data of that telescope?

Well, the James Webb is fantastic, but I would not spend its time on starquakes. And so let me explain why. You know, James Webb can pierce very deep into the early universe in the infrared. What I need as a seismologist is really long-term measurements. And that's why we love the Kepler mission of NASA and now the TESS mission and the future PLATO mission

because they're staring at stars for years without interruption. And so you don't want to spend James Webb on that because it has, as you say, so much other fantastic extragalactic science to do. So I don't want to hook on James Webb, right? Of course, at all times in our field, Matt, we're always judging whether you need one particular telescope for that task versus another telescope that might be either more available or less a cutting edge,

because you want the cutting edge telescope for the cutting edge science that's going to break open whole new fields, typically. So, yeah, that's a very important point that you're mentioning there, Connie. But I want to also ask, that's part of the great computational challenge, because if you have a lot of quakes of all different frequencies short measurements cannot distinguish one from the other correct you need a very long baseline so that you can tease out of the data frequencies that are represented enough to know that they're real did did i characterize that accurately? Yeah, that's very well described. And in practice, you know, the precision of the frequency goes as one over the total time base of the measurements. Yeah? So if Kepler measures

four years, well, that's one over four years in frequency resolution, as we call it, capacity to unravel these dark wave frequencies. So we need to be very... Astro-seismologists are very patient people. So what you're saying is if you... So I like that. So if you measure something for four years, you can't really say much about frequencies that occur on two-year time scales. Because you would have only had one or two cycles in there, and that's not enough to

even know if they're real. So you need enough cycles in your baseline of data to be able to say, yeah, that's real. Yes, it's repeating, and it's reliable. Yeah, that's right. And so that's why we need these long time series and we can only do the work once we achieve that. So we need dedicated space missions to achieve that. And James Webb is just not one of them. I got it. Interesting. Please leave James Webb to the people who need it. And I'm not one of them. All right. That's very magnanimous of you yes so so just to update people so kepler was a telescope that looked in one part of the sky looking for um for earth-like planets around sun-like stars studying them for a long period of time

tests that what's that that's an acronym for what i I forgot. Transiting Exoplanet Survey Satellite. Satellite, thank you. So TESS will see the entire sky, but not quite to the depth in space that Kepler did. And so now what is PLATO going to do? And is that also an acronym? Yeah, well, PLATO stands for Planetary Transits and Oscillations of Stars. And PLATO is actually going to, from construction, combines the best of both worlds of the Kepler mission and the TESS mission,

in the sense that we need long-term observations, but we also need the whole, not the whole sky, but a very, very big part of it, to have copies of the Earth in our line of sights that rotate around copies of the sun. It takes a year for us to revolve. And so, Plato has that built in. It's actually, it's 24 telescopes on one big platform.

Oh, my gosh. Okay. I didn't know that about it. So, it's a multi-telescope instrument that is being built by the European Space Agency right now. I tend to call it my third child because I've been… You're deep involved in the design and objectives of it. Congratulations for that. Yeah, so that's exciting.

I want to see the data before I retire. Kepler was a famous German mathematician who coincided with Galileo, actually, in time. And we all heard of Plato. But I don't know any TESS. So TESS was an acronym, but not an acronym of a famous scientist of the past. Exactly. Exactly. Okay.

So they don't always work out the way you mentioned. Well, yeah. Just as long as the machinery works for us, Tacitus. You don't care what the hell you call it. All right, so Matt, keep it going. What do you have? I am going to try and get through as many of these questions as possible. I am going to try and combine four different...

Let's ask Connie and see if she can do a lightning round. Here we go. We're combining four questions. They said it couldn't be done, but four different questioners between... Because a lot of people have asked about the effect of sunspots on starquakes and how they affect earth so charles macko asks how they affect starquakes um trevor mills says how close would a nearby star have to be for a starquake to be considered dangerous for earth and then sarah rosen says how big of a cme would it take for the sun's gravity to be negatively

affected and gina martin, why didn't the one the star quake back in 2004 wipe us out? I've read that it released more energy than our own sun would emit in 150,000 years. Okay, so let me tighten all those up. So Connie, clearly there are quakes going on all the time, and I presume

that a CME, a coronal mass ejection, is itself detectable as some kind of quake activity. So, and of course, sunspots are measures of the activity of the sun. So, but you haven't mentioned solar flares or coronal mass ejections or sunspots yet, not much in this conversation. So what role do they play in all of this? sunspots yet, not much in this conversation.

So what role do they play in all of this? Oh, well, the role they play is they disturb the periodic oscillations of the sun, but it's not bad for us. Why not? Because coronal mass ejection or sunspots that rotate around, you know, they do not give the same signal in the periodicity of the quakes. I'm quaking my microphone right now. So you know, a coronal mass ejection is an abrupt event.

It's more like an earthquake you could say. It happens and it disappears, right? But it doesn't disturb us finding the five-minute oscillations of the sun, which are always there. They get disturbed abruptly, but then they continue and they continue and they continue all the time. So for us, we can unravel the signal of star spots, of mass ejections, even for stars other than the sun,

from the always smooth periodic oscillation. So how about the dangers that they might pose if you do have a coronal mass ejection that happens to head towards us? Yeah, so the Earth is protected by a magnetic field that protects us from all these high energetic particles falling in on our planet. And other stars are too far away. So, I mean, it's only a matter of the solar quakes. They are not dangerous for us. The

coronal mass ejections, they disturb our electronics every once in a while, right? But, you know, that's not a periodic oscillation that I would call solar quakes. I forgot that you enjoy events like that, even if they mess with our computers. That's how we started. I forgot that. I learned that earlier in this podcast. Yeah, that's true. So that almost counts as a lightning round, Matt, because she answered three questions in one reply.

She did. Let's see if we can get a few more in before we call it a day. James Allen from Brisbane in Australia says, could a starquake large enough theoretically cause a star to tear apart and would descend a high radiation blast like a supernova? What could we learn such things from our own star? A starquake would not rip apart a star because it's really a smooth, nice periodic variability.

You know, the biggest starquakes in terms of expansion and contraction, let's say, can make the star become bigger and smaller by about 10% in its radius, let's say, but not make it explode. That's another phenomenon. Okay. Again, that's people thinking that a quake is a spontaneous bad thing. No, it's a fantastic smooth thing. It's a fantastic smooth thing.

Well, on that same note, Connor Holm from Squim, Washington says, is it possible to predict where and when a star quake will occur? And if so, what's the largest predicted star quake and how much bigger is it compared to the largest recorded one? Well, star quakes happen all the time. I keep repeating that. Let me ask it differently then. What variety of your oscillations carries the most energy? Well, the simplest starquakes are radial oscillations, you know, up and down and up and down. oscillations, you know, up and down and up and down.

So everything is expanding and contracting while keeping spherical symmetry. So that's about the, the, you know, the largest energetic, uh, it can get. And that's for me, just a simple oscillation because it's a radial oscillation. Variable stars, I guess, right? Yeah. Yeah.

Yeah. Yeah. So Cepheids are Lyrae stars. Yeah. I guess, right? Yeah, yeah, yeah, yeah. So cephalids are our light ray stars. Yeah, I mean, it's half a star. I mean, some huge fraction of stars in the night sky are variable, presumably for this reason. And I heard when I was in graduate school, Connie, that if you looked at every star close enough with sharp enough data, they're all variable. Of course they are. Everything oscillates. Of course. close enough with sharp enough data, they're all variable. Of course they are.

Everything oscillates. Of course. So we just have to draw some arbitrary line of what we catalog as a variable star relative to other stars. But really to you, everybody's got action. Well, we're measuring the action up to parts per million. Yeah, there it is. Right? You got it. Part parts per million. Yeah, there it is. Right?

You got it. Parts per million. You got it. Okay, Matt, let's get one more, slip one more in before we got a call. All right. Margaret Defoe from Milwaukee says, why didn't our solar system go binary?

And what is the smallest and largest a star can get? So we're on more general questions about stars, I think. Yeah, let's hold aside the largest and smallest. That's a whole other astrophysics question. But Connie, what do you say about why the sun is alone when so many stars in the night sky are binary in multiple systems? Yeah, well if you look at the star with the mass of the sun, then half of them are in binaries, so that means that half of them are alone. So it's a toss. It's an equal toss, right? Yeah? So that's not so exceptional.

But if you go to stars... That's not the answer we were looking for. We wanted you to say, we might have had a double and then it blew up. We want a more sci-fi answer here. It was originally a twin. We lost one of them. It ate the other one in the womb.

It ate the other one. I don't think so. I don't think so. I don't think so. But that happens frequently when you go to higher masses. If your star is born with 10 to a hundred times more mass than the sun was born with, well, then about 80% of the stars are multiple, double stars. Yeah. So for the sun, I think it's just a logical consequence

of there only being half of them that live their life together. Okay. Luckily for us, it wouldn't have been so nice here if it would have been living next to a star that has exploded already. Yeah, it has issues. But that's definitely a yet-to-be-fi drama i think sci-fi action film yeah whatever happened to the sun's twin you got it well connie it's been a delight to have you on star talk and like i said uh my city my my town is your town so i'm a native of new york city

you're visiting for the sabbatical maybe we can get you up to the museum and give you a tour and possibly extract, extort a seminar from you for our astrophysics group. I love this city, so I'm very grateful that you're hosting me. Excellent. Excellent. Matt, always good to have you, man. Oh, it's a pleasure to be here. Thanks for having me. And this has been great. I've loved hearing about this stuff. We got to land this plane. So thanks for joining us on this episode of StarTalk Cosmic Queries, Starquakes. I'm Neil deGrasse Tyson, as always, bidding you to keep looking up.