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  • how I pronounce this star.

  • Well, that's a good question.

  • So I ran a Twitter poll on the altar is Nobody seems to know.

  • Well, you're an astronomer.

  • What do you say when you're an astronomy conference and someone says so?

  • Professor Mary Field, what do you think about the latest happenings on Betelgeuse?

  • I don't go to that kind of conference because I don't do stars.

  • It's difficult because it's a corruption of an Arabic name.

  • So, actually, quite how your prints supposed to pronounce a corrupted Arabic name, I'm not sure.

  • So you can really pronounce it.

  • How you like.

  • Let's get with beetles.

  • Usually it's a star.

  • It's a relatively massive star, but 10 times the mass of the sun.

  • It's if you look at the constellation of Orion, which is one of the few that most people recognize is the star at the top left of her of Orion.

  • And the reason why everyone's excited about it is because it's fading at the moment quite dramatically.

  • Andi.

  • Other interesting fact about it is that in astronomical terms, it's likely to blow up sometime in the near future, and people have kind of put these two facts together and equated the fact that it's fading at the moment as a sign that is about to go.

  • Wow, is it about to go?

  • I think it's unlikely.

  • So I was a bit careful in what I said, and I said, In astronomical terms, it's going to go pretty soon, and that just basically means it's probably gonna blow up sometime in the next 150,000 years, So the chances of it being tomorrow are pretty slim.

  • I would say is actually well documented is a variable star it has.

  • It's some sort of quasi periodic things.

  • That's the longest time scale variation.

  • That's a shortage timescale variation.

  • So there's lots of variability going in it on.

  • It is a complete mess.

  • And so, actually, although this is the faintest it's Bean in recent times, it's not really unprecedented for it to be fading.

  • If and when it does blow up, will that be preceded by a sudden and dramatic fade?

  • Nobody knows, because no one's ever seen one of these things that close up.

  • I've seen it before.

  • It blew up to know what it's going to do, so no one really quite knows and the reason.

  • Part of the reason why no one knows is because it really is a very messy system.

  • It's big, extended, bloated kind of thing.

  • That's all sorts of processes going on, innit?

  • So quite what the sequence of events would be that you'd actually see from the outside is really something of a mystery at this point.

  • No, I thought we modeled stars all the time.

  • And we've got all these theories about what the explosion looks like and how a supernova works.

  • And it was supernova.

  • It will be a supernova.

  • And yet you're right.

  • You know, we sort of have a broad brush understanding and the sort of the physics that's going on.

  • But it's like, you know, it's like the difference between climate and weather, right, that actually, even if you think you know what's going on in the climate, you don't know what tomorrow's where that's gonna be like, really What's going on in the outer layers is very much the weather.

  • Andi, the climate is the explosion.

  • That's gonna occur right in the core of it.

  • On how these two things a couple together is really quite complicated.

  • So we really don't know what you'd expect to see in the days, months, years leading up to the explosion because before this big orgy stuff, if you'd asked, may ready.

  • What do you think happens to a star in the year or two of the week between before it blows up?

  • I would have said, I bet it gets really, really bright on.

  • If you'd asked me the same question, I probably said the same thing.

  • You'd think that that would be what would be going on.

  • But as I say, it really is, because what's going on right in the middle, where there were probably are some pretty frantic nuclear processes going on writing those, like dying days of the star on what you actually see in the outer parts are really only very loosely coupled together.

  • So it really isn't that clear what you'd end up seeing in those last few weeks.

  • But you think, Look, if you're a betting man, I'd be prepared to put a fair amount of money on it not going in my lifetime, which would be a shame, because I'd like to see it, but probably not.

  • It would do a bit of a job of astronomy for awhile because when it does go, it's gonna be brighter than the moon or about as bright as the moon on DSO.

  • The kind of astronomy I do I tend to do away from full moon.

  • Andi, it's gonna be like having another bright light up there.

  • This is almost as bright as the full moon.

  • So for a year or so, the kind of astronomy I like doing is gonna be quite hard to do because I'll be the new bright light in this guy.

  • Elon Musk was ruined straight on for the dramatic.

  • For the drama of getting to see you start blowing up, I'm prepared to put up with not doing my kind of astronomy for years.

  • You said you'd be willing to put money on it.

  • Not being in your lifetime.

  • That should run markets on astronomy.

  • They don't really, ever doing that.

  • I open it, but you can bet on everything.

  • Can't.

  • You can bet on who's gonna be the next prime minister and who's gonna be that they should have bets on astronomical events.

  • I'll bet you could, you know, if you wanted to, I'm sure your local bookie would be able to figure out some words for you if you wanted to.

  • I actually have a national local bet which has been running, and I don't actually know.

  • I don't know where the betting slip here, So I have to find it one of these days, which is that I put a bet that they would find life on Mars years and years and years ago.

  • Andi was quite interesting process, actually, because I went to the bookmakers and then the opposite, they couldn't do anything there and then, But then they have specialists, right?

  • And they put you in touch with their specialists on.

  • I had a chat with Specialist.

  • I had assumed that they would like, insist there being some time of it.

  • You know that you find life on Mars sometime in the next 10 years because otherwise it's just the bit that goes on and on forever.

  • Actually, it turns out they don't care because they get to keep your money until the bets settled.

  • So I have this bet that they will find life on Mars.

  • And there were various criteria like it had to be no microscopic and those kind of things that bacteria wouldn't count Those kinds of stuff.

  • So what were you thinking?

  • You weren't thinking little green men.

  • I reckon the well I don't know what I was thinking.

  • Really?

  • I just thought it was a fun thing to find out whether you could put a bet on finding life on Mars or not.

  • We're rather than actually thinking they'd find anything.

  • Andi think I'm trying remember the exact terms.

  • It didn't actually have to be alive so they could find, like, fossil remains.

  • So as long as it wasn't like microscopic that then then it was I would win the bet.

  • But I have to find the betting slip one of these days to find out.

  • Do you think you're gonna lose that bet, or do you still think you might?

  • Well, that is a winning.

  • I reckon there's still a chance.

  • All right.

  • Yeah, It's a little little.

  • Maybe it'll pay off.

  • I think.

  • Uh, you know, Mars was a much nicer place a long time ago.

  • And, you know, there was water around.

  • There was an atmosphere.

  • So you're who knows?

  • Maybe there was like, when big orders does go?

  • Yes.

  • Do we know it?

  • Is there anything we get any clues that it's about to go.

  • We will get a little bit warning.

  • So I was intrigued by this, and I heard various stories about whether we get any advance warning or no.

  • And the answer is we will.

  • So I found a paper.

  • It was published a couple of years ago.

  • Neutrinos from beater processes in a pre supernova probing the isotopic evolution of a massive star.

  • They do, ah, calculation of what the last few hours off a star's life is like just before it goes supernova.

  • Remember, the way a star is powered is it burns the various chemical elements from one to the neck.

  • So by nuclear fusion, it will turn hydrogen into helium and then helium into carbon and so on up, creating heavier and heavier elements on dhe.

  • The problem with doing that, if you're a star, is that each time you get less and less bang for your buck, you know each that the hydrogen to helium processes, you get quite a lot of energy out helium to carbon a bit less, and so each time you get less and less energy out, which means that in order for the star to kind of hold itself up.

  • It has to burn things that they're nevermore frantic rate in order to do so.

  • So the lost stages of burning are really very intense, but not very energetic.

  • They don't actually produce much energy, and they don't last very long because it uses up the fuel very, very quickly.

  • And so this is looking at those last few stages and asking, You know what, all the processes, and actually more importantly, is there anything we could detect that would tell us that those processes were going on and in particular the thing that will get straight out from the star of the neutrinos?

  • So one of the byproducts of lots of nuclear reactions is that you produce these pathetic little particles called neutrinos.

  • Basically, whenever you turn a neutron into a proton or a proton into a neutron in some process, you tend to produce one of these neutrinos on.

  • Neutrinos are such wimpy little particles that they'll actually travel straight through the star on, but they don't really care that a whole body of a star around it, so any neutrinos produced will stream straight out.

  • And what these guys did is they did some calculations as to say, how many of these neutrinos, all that And in those last few frantic hours, when you're burning all these things as quickly as you possibly can, turns out the process is so intense you make a lot of neutrinos.

  • So Start spends all that time burning fuel on dhe over millions of years.

  • But the final fuel event is something measured over our hours.

  • Yes, literally hours.

  • So it really is that frantic that is desperately trying to stay alive.

  • So it's using up all the fuel it possibly can quite sad.

  • Almost.

  • It's pretty pathetic, really drowning, you know, Really, it's this frantic.

  • Oh my God, we got to keep going.

  • It keeps burning all these things and eventually, you know, it just runs out of things to burn.

  • So they do these calculations, they figure out how many neutrinos get produced.

  • And so here we are.

  • This is the number of neutrino is being produced per second.

  • And so they did a couple of calculations 15 solar masses and 30 solar masses.

  • Beetlejuice is around probably around 10.

  • But this Oh, this is reasonably close to the kind of thing that would be going on the Beetlejuice and you could see this is the luminosity in the number of these things being produced per second.

  • You could see as it's coming up towards the end here the curves will going up and up and up and up one hour before the thing goes.

  • We're looking at 10 to the 52 neutrinos being produced for second, so it's a huge number of neutrinos.

  • Then, of course, they sport out through space.

  • So by the time they get to the earth's many fewer off them and then you need a neutrino detector.

  • And that's a hard thing to do because neutrinos just passed straight through everything and so stopping neutrinos.

  • Detecting neutrinos is a hard thing to do, but we have some new tree noted Texas on Earth, and they're mostly designed to do things like detect neutrinos from the sun.

  • But it turns out that we might actually hope to detect some of the issues in the earthbound neutrino detectors so they go through that built the calculation as well to figure out what you'd actually expect to see.

  • So they looked at various neutrino detectors.

  • June and you know don't actually exist yet, so they're ones that are being built at the moment.

  • Super Kamiya Conda is one that does exist now on they add up all the neutrinos you'd expect to detect.

  • And they reckon you detective slightly less than half a neutrino, which doesn't sound too promising until you realize that this calculation was done.

  • Assuming a star that was about five times further away than beetle uses.

  • And so the number of new.

  • So the neutrinos spread out through space.

  • That kind of fill the whole area, which means that the number of neutrinos you detect decreases as one over the distance squared.

  • So if the thing's five times closer, that means you see 25 times as many neutrinos.

  • So are half neutrino turns into about 12 neutrinos.

  • That doesn't sound very many, but remember that the only previous time we've detected neutrinos from the supernova was when the supernova went off in 1987 in the large Magellanic cloud.

  • On there, they got very excited because they detected 10 neutrinos.

  • So this is kind of in the ballpark that people are used to detecting from neutrinos and getting excited about when they detect them.

  • Eso actually it will sort of set off the neutrino alarms when it happens, and they will actually have this involves notice.

  • They even, I think have some directional information.

  • So I don't even know that that these neutrinos that came from the general direction of Beetlejuice is there a system in place for the detector to tell all the telescopes to swing around and point of Beetlejuice?

  • I'm not sure there is, Andi, Actually, I'm not sure they can process the data that quickly.

  • Whether that whether it would only you'd only find out after the fact, which is what happened with supernova 1987.

  • 80 Actually only found out afterwards that actually yes, we did, Detective the neutrinos.

  • The good news is, if it hangs on for a few more years to these other neutrino detectors come online and you can see that actually where super coming of condoms, only detecting half a neutrino.

  • The Juno detective will detect 17.

  • So and they're going remember, that will go up by a factor of 25 just because it's closer than that.

  • So if we wait around until Juno's online, they will detect lots and lots of neutrinos and that really would be a big burst that would be set off some alarms.

  • I suspect you talk about advance notice, but that's not because anything bad would happen if not to us.

  • No, we're far enough away.

  • That actually all your seasonal big, bright light in the sky.

  • But it's not the gamma rays or anything like that.

  • I'm going to kill us from Beetlejuice when it goes how far?

  • This is a long way away, isn't it?

  • So this is like all stuff in the past.

  • Yes, it's, Ah, 700 light years away.

  • So, yeah, it could have gone by now and we might have to wait around for a few 100 years for the event to get to us.

  • The neutrinos travelled to Earth at the same speed as light, sold like it's not like the explosion will overtake the new trainers.

  • No, and in fact, because because they'll be neutrinos created in the explosion itself on again a really, really big number of neutrinos.

  • So actually this is the sort of pre supernova stuff.

  • But when the explosion really goes, there'll be a huge burst of neutrinos and actually they will get to us before we see the light because the neutrinos come streaming straight out.

  • But you gotta have This explosive shock wave has gotta work its way through the the body of the star before we actually see the light of the supernova.

  • So, in fact, when the supernova goes will get a little bit more warning that the neutrinos will arrive before the explosion does.

  • But Earth is safe, something that far away.

  • It's not like that Wigan like there's gonna be any war with heading towards Earth that's gonna cook us, Really want a sale?

  • Lucy's It will be a dramatically bright light in the sky, but nothing's gonna fry.

  • How dramatic when you see it in the daytime and it'll be visible in daytime.

  • It'll be about the same brightness.

  • Is the moon so visible in during the day?

  • For And I think you'll see it during the day for a matter of weeks or months, and it'll be visible to the naked eye for a year or so.

  • Awesome.

  • Has there ever been a sleeping over in our galaxy that we've observed?

  • No.

  • In recent times, I mean, there were So the Chinese records has records of supernova Randolph, 1000 years ago so that have bean supernova in the in the Milky Way Nebula was one of those exactly the crab members on the only one that sort of in in recent times was supernova 1987 a, which was in the large Magellanic Cloud in our near neighbours.

  • Robin actually being in our galaxy, okay, I love to see what it would be.

  • Pretty cool.

  • You should call the bookmaker and find out what's going on.

  • Beetlejuice going?

  • Yeah, probably not very good at the moment, because it's been so much noise about it.

  • You didn't see the picture.

  • What's that?

  • There's a picture.

  • This is what beetle you.

  • Just to give you a sense of what a supergiant star actually looks like.

  • This is a picture off Beetlejuice.

  • It's sufficiently big that with the very high resolution telescopes that we have, like the Atacama large Millimeter array, where we can see exquisite detail, we can actually make a picture off the disc of the star itself.

  • And that's partly because this telescope can make incredibly high resolution Sharpe images.

  • But it's partly because the thing's enormous in that somebody's drawn on here.

  • What the orbits of the planets in the solar system would be, and you can see that actually is bigger than the orbit of Jupiter.

  • It's a truly enormous object.

  • The other thing you can see about it is it is a complete mess, right?

  • That actually is Noah.

  • Nice uniforms, fear.

  • There's a bright patch over here.

  • There's indications that is not even exactly round.

  • That's because it is this very sort of churning convicted system.

  • It has huge convicted of cells as things rising, things falling, things being spat out that actually it's a very non relaxed system on.

  • That I think, is probably what lies behind the current fading that there's one of these phenomena is going on.

  • That's just maybe it's spat out dust or something that which is currently obscuring it so well we're currently seeing is just some one of these processes that's going on in the outer layers of the star, which just just made it fade in this rather dramatic way.

  • Two stars this big have planetary systems, as I understand it like this'll what?

  • No, I mean, it might have had Remember this isn't it supergiant phase?

  • Before that, it was a regular size star so if it had a solar system like the Earth, it would have bean eaten up by now.

  • Site.

  • Somewhere inside Beetlejuice might be like the remains of civilizations.

  • Well fried.

  • At this point, I suspect, yes.

how I pronounce this star.

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