Super-Duper Novas with Michael Shara

30:33So is there a crown in the Southern hemisphere too? There is Corona Australis. Okay, good. So that's why you specify the Borealis. That is correct. Yeah. Okay. So pick it, pick it up from there. We saw this star last erupt about 79 years ago. And then 80 years before that, we saw it erupt as a nova and each time it became about second magnitude. And one of my colleagues, Brad Schaefer, has made a pretty good case for it having erupted 80 years before that. And then he even points out some possible evidence for an eruption in the 1200s. So this is a star, this is a recurrent Nova. Wait, nobody was looking up in the 1200s.

31:13They were just trying to not whatever. Not starve to death. Get eaten by dragons or not starve to death. Or die of the bubonic plague. No, no, no, there were people who actually did notice changing stars. things that were wild. And of course, there were no electric lights in those days. Yeah, a lot more stars to look at. Actually, sorry, it was the 14th century, which was the only century where the population of the world was lower at the end than it was at the beginning. From bubonic plague and all of this. Black death will do it every time. That's why I can't stand that they called it the black death.

31:51Of course, the most deadly of deaths has to be the black death. No, go ahead. Okay. I'm being silly. Go ahead. No worries. So this star, this massive white dwarf is cannibalizing its companion, which is a, in this case, a red giant star. Authentic red giant. This is an authentic red giant. Can you see both stars when you look at them? Or are they too far away? You can see neither. It is roughly 13th magnitude in quiescence. So if you look with a terrific pair of binoculars, you still can't see it. You need at least, if you want to see it with your naked eye or with your eye, you need at least say an eight or a 10 inch telescope to be able to see it.

32:33So a really good backyard telescope would catch this. We'll see it when it's in quiescence. Okay. And it's going to jump in brightness approximately 100 ,000 fold to reach roughly the brightness, a little bit brighter probably than Polaris for a few hours. And then it'll fade away. Oh, wow. And then on a timescale of a week or two, you won't see it again. And you won't see it again for another 80 years. So when I was in the Pacific Northwest, I took a photo of your star. And I don't know if I got to show it to you. Did I? Did I ever show it to you? I think you might. Because, you know, there was a chance it could have blown up while I was looking at it.

33:11Exactly. And then I'd be the first. To have seen it. Or at least have recorded it. I'd have been the first out of the box on that one. Yep. Everyone wants to be the one to see it starting on its rise. Of course. And so people have little charts and okay, there's T Corona Boreal. So somebody's watching this thing every night. Of course. Someone is watching it basically every minute. 24 hours at day. 24 seven. Because half the world is dark at any given time. And we got people everywhere. Of course you do. There are tens of thousands of so-called amateur astronomers who are every bit as professional as professional astronomers.

33:46In that community. Go ahead. And it is a badge of honor to say, I am an amateur astronomer. If you say that, you can ask them any question about the night sky and they'll have an answer. They know. Even some of my colleagues wouldn't know because they know the night sky. They're out there every night. As I was when I was, you know, had my backyard telescope. Except my rooftop, right? There's no backyard in the Bronx. I was hauled to the roof. So the thing for me that is most exciting about T. Corona Borealis is that as a recurrent nova, it was predicted, and there were only 10 recurrent novae known in the whole Milky Way about a decade ago.

34:28It was predicted that, boom, you blow off a shell of matter. Then 80 years later, boom, you blow off another shell, another, another, another. The stuff doesn't all come off at the same speed. Some of it comes off at high speed, some at a lower speed. So what that means is when the next shell goes off. Someone's going to overcome. It's going to, the fast stuff is going to overtake the slow stuff. Bingo. So you're going to have shells colliding with each other. When shells collide. Shells colliding, Jerry. No, that's amazing. And so it's going to be a traffic pile up. Right. It's like, you know, one car running into another.

35:07And if that's right, that hasn't just been happening for 80 or 160 or 240 or 320 years. It's been going on for thousands or tens of thousands of years, which means you've got hundreds or thousands of shells piled up on top of each other. That means you should have a super shell, a super remnant surrounding T. Corona Borealis. Where the fastest stuff is plowed onto itself. Right. A bulldoze its way through. But that's not all. Wait, wait, there's more because as that shell builds up in mass, it's also acting like a snowplow, plowing up all the stuff in the interstellar medium in front of it. The stuff that's there anyway as bystanders.

35:56Is going to get mowed over and is going to be incorporated into that super shell. So there should be a super duper shell around it. And we've just found it. Oh, he buried the lead. You heard it here. What? So we've been using a gorgeous new, not expensive telescope. Oh. The kind of telescope that so-called amateurs use, refracting telescopes. Six of them bolted together in parallel. And we stared at T. Corona Borealis for about a hundred hours. They're not in darkness for a hundred hours. I just want to make that clear. Oh. Okay. Yeah. They get the dark stuff tonight. Right. They close the hatch and then tomorrow night pick it up again.

36:42We're back at it. Okay. Back at it. Okay. Go. And so we actually have thousands of images taken over more than a hundred nights of T. Corona borealis. And we add up all those images and we took pictures through filters that only transmit the light from hydrogen, only transmit the light that comes from nitrogen ions, sulfur ions, and so on. And we found a super shell surrounding T Corona Borealis. That's about three times the diameter of the full moon. That's fabulous. So it is a degree and a half on the sky. And you might then think, well, when T Corona Borealis goes off, it's going to be like a flash bulb going off in the room, in a room full of little mirrors.

37:26it's going to be like christmas lights going off as this flash of light right propagates outwards echoes off the material that's super show one would hope that that would be true that's amazing it's probably not oh no so the downer is we published in a paper that just came out a couple of months ago saying there's not going to be fluorescence okay so the atoms themselves are not going to light up because they're too far apart and there aren't enough of them. That's not going to be bright enough to detect. Now, maybe just maybe if there was dust, little grains of silicon and carbon and other what we call refractory elements, high temperature stuff, little grains that were tossed out in the last nova eruption, the one 80 years ago, those might reflect enough light for us to see as a light echo.

38:24And you know that a day or two or three after this goes off, the Hubble Space Telescope is going to get pointed at at the James Webb Space Telescope. Yes, we're very good about that. Something happens, everybody - Comes together. We are the most - Shares information. We are the most come together. We're always about a collabo. Always. Especially since not every telescope will observe it in the same way. Yeah. So you get different kinds of data coming together. I always say the only people to collaborate more than rappers are astrophysicists. So Mike, on my iPhone, I controlled a digital telescope when I was in the Pacific Northwest.

39:00Didn't even leave the comforts of the living room when I did this. See, he's old school. He's like, what? You didn't like ascend the mountain? You did not suffer for that image? I've been up in the prime focus cage of telescopes for nights at a time. Tell me about it on your rocking chair. Exactly. Right, right, right. So this image, I found it, but it was behind a very modeled tree. And so the digital telescope tracks it. But so the tree ends up blurred as it's tracking the actual object. So it's a very undistinguished dot on my picture. Had you caught it near its maximum, you would basically have saturated the image.

39:41Yeah. All of the image would be just one bright point of light. Wow. But there's no saturation anymore because this knows what it's doing. It takes 10 second images. Yes. and then stacks them. Right. In the old days, you expose it. You overexposed. It would get overexposed. Now you don't have that problem because you're getting all separate images. You stack them and add them and you get it. Keep going. All right, let's keep going, man. This is really cool stuff.

40:27This is Joel Bradley, and Joel says, greeting Dr. Tyson, Dr. Shower, Lord Nice. Joel here from Geelong, Australia, and I have a question regarding our favorite pre-supernova star, Beetlejuice. Whilst I understand that life of a star is extremely long from our perspective, How is the time frame for Betelgeuse going to supernova between now and 100 ,000 years? Is there any sign that will warn us of it happening in our lifetime? Or will we just look up one night and go, oh, wow, look at that. There it was. There it is. What's the life expectancy of Betelgeuse from birth to death? Something like, well, the star itself, if you consider the main sequence lifetime, probably a few million years.

41:15Got it. Okay. Okay. So it was hydrogen burning for a good fraction of its lifetime, maybe a million years, maybe two, three million years. Again, when it's astrophysics speaking, he means hydrogen fusion. Right. Of course. So Betelgeuse was initially as a very massive star fusing hydrogen into helium. Then it left the main sequence, ascended the red, and then the red supergiant branches. Ran out of hydrogen in its core. Ran out of hydrogen. Needed to do something else. Needed a new source of energy. Otherwise, it was going to collapse. the core got dense enough and hot enough for helium to start fusing into carbon and helium has two protons in its nucleus oh now you got to get two protons next to two protons you got to be hotter than whatever you were for hydrogen look at that typically you've got to be in the 100 million degree range instead of the 20 million degree range in order for that to happen okay so it is really hot down there in the core of betelgeuse betelgeuse has only got probably in the best case, a hundred thousand years to go, but it might be tomorrow.

42:15Okay. That's a really bad prediction. Can you do better than that? 50 years ago, the prediction would have been, we don't know why it's a red super giant. So we have gotten a lot better. Yes. We would love to do better. And the answer is if you - We should appreciate how far we've come, even in our ignorance. If you give me enough money, I will build a detector that will tell you several days in advance when it's going to go off. Nice. And what is that detector going to be? Well, it's going to be the biggest, baddest neutrino detector that's ever been built on Earth. Right now, we've been super clever.

42:53We, meaning physicists collectively, not me, have built enormous detectors using cubic miles of seawater or ice. The ice cube detector, for example. In Antarctica. In Antarctica. And a gorgeous detector right near Sicily, a huge underwater detector. And the wrapper ice cube goes down there and performs for the scientists. Not. Not. But if we could build a detector that was say, oh, a thousand times the volume. So instead of a mile by a mile by a mile, we'd love to build something that was 10 miles by 10 miles by, by a, by a few miles, at least, we'd have a thousand times the sensitivity. Now, why do I care about neutrinos?

43:35Well, as the star is right near the end of its lifetime and just about to flash off, it's not just going to burn. Do you see the light? Do you see the light? Yeah. It's going to burn the carbon into magnesium, the magnesium into heavier elements, all the way up to iron. And you're going to get a great flux of neutrinos coming out of the core of the star in the last few hours, maybe days of the life of the star, certainly in the last couple of minutes. And then during the implosion, you're going to get another blast of neutrinos. So these will come out of the star before anything else. Okay. But they're not going to speed of light.

44:22They're not. So what? So. Doesn't matter. And the reason it doesn't matter is that Betelgeuse isn't that far away. We're talking hundreds of light years. We're not talking millions or billions of light years away. And as a result, the difference between the speed of the neutrinos. Which is very fast. Which is very, 99.9, many nines, the percent the speed of light. The difference in speed between the neutrinos and the gravitational radiation that will be emitted. And that's going to the speed of light. That is moving exactly at the speed of light. And we have something that could detect that if it happens.

45:00We have several detectors, at least three up and operating now that are going to detect those gravitational waves. Are they all collectively LIGO or is it just the American ones called LIGO? The, they're collectively called the LIGO, LIGO, and each one of them has its own name. Okay. For example, the Italian one is referred to as Virgo, but the LIGO, if you will, the LIGO assembly is, is the three telescopes. We get the gravitational waves. Right. And they will come at the same speed as the explosive light, I presume. They, they're going to precede the light. Oh, because you have the collapse.

45:38You have the collapse and then you got to expand again to get big enough to have a photosphere, a radiating surface big enough. So it's going to be tens of minutes to tens of hours before you see it in the optical. This is going to be amazing. You'll see them right one, right after another, each of these, the sequence of events. So we're going to see the gravitational radiation and the neutrinos arriving almost simultaneously. simultaneously, we may get lucky and see a few of the early neutrinos coming a few seconds or minutes early. That would be just in the last gasps of, oh, I'm just, I'm finished my carbon burning.

46:19I'm going to do my magnesium burning. That didn't help me. I'm going to do my, my silicon burn. That helped me even less. I'm going to do my iron burning. So you get more and more frantic. I've never seen you imitate a star before. That was pretty good. That was it. That That was a dying star right there. And so. Because what he's doing is the star is trying to not die. Right. And so it's finding every possible. It's finding everything it can do to burn. And if it can't, if it's not enough, it's going to collapse on there. And so maybe in that last minute, we'll start seeing a neutrino here, another one, another one, another one.

46:51And then tens of thousands of them are arriving. And that's going to be the herbinger. That's going to tell us supernova coming. Supernova time. Supernova is coming from there, that direction. If we have all three detectors, you can triangulate back on it. We can triangulate to about plus or minus a degree, you know, a little bit more than the area of the full moon on the sky. Yeah. But how many supernova progenitors are in the area of a full moon on the sky? We typically get, you know, I mean, I, in a, in a square degree, we've got millions and millions of stars. You don't know which one it is, but if you triangulate back to that one square degree where beetlejuice is.

47:30If beetlejuice is in the middle of the thing. Right. That's pretty much another deal. You should go whoop, whoop, whoop, whoop. Turn on your alarms. So how bright will beetlejuice get? Because it's already bright. It's like, what is it? It's, it's, it's zeroth magnitude. What is it? Maybe minus. Minus one, maybe. Something like that. Yeah. It's certainly one of the, you know, 15, 20 brightest stars in the sky. Way brighter than the North Star. Once again. Right. So right now, currently it's maybe a million times. Yes. The luminosity of the sun. Okay. But it's going to go to at least 10 billion times.

48:02It's going to get at least 10 ,000 times brighter. Wow. Wow, so then 15 magnitude. It'll be visible in the daytime. Oh, it's certainly going to be a daytime thing. It's going to compete with the full moon for brighter. That's great. Probably cast your shadow. No question. Oh my gosh. No question. Joel, there you have it, my friend. If you have a neutrino detector, you will know exactly when this is going down. You will go first. If you get the neutrinos and you get the gravitational waves at the same time, just know, Elizabeth, I'm coming to join you, honey. Betelgeuse is about to kick the bucket and you can watch it.

48:36So that's super cool. One good piece of news. I mean, you're headed in absolutely the right direction. I don't want you scaring anyone, though. Okay. You don't need to go down to your basement or your sub-basement. because even though there are going to be lots of high energy neutrinos coming and whacking you, none of them's going to hurt you. There aren't going to be enough gamma rays to fry our ozone layer. Or make you the Hulk. Or make you the Hulk or give you a sunburn. So don't worry about that kind of stuff. It's just going to be something ultra cool that you can walk out and see something that really nobody has seen since the 1600s.

49:16So we had two supernovas almost back to back. Well, Kepler had one. Was that, how bright was Kepler's supernova? It was also the same kind of brightness. Maybe not quite as bright as that. In the daytime? It was seen in the daytime probably for a month or two, but I got to go check that out. So let me ask you both of this then. The most famous star in the night sky and also reportedly shown during the day, the star of Bethlehem. Do we have any real record of what that was? Go on, ask the Jewish man about the star of Bethlehem. Go ahead. So my forefathers did not draw a diagram or a map of where it was.

49:59In fact, this only appears in the New Testament. Right. As a star in the east. Star in the east. You know, that's a little vague. You think? A little too vague. A little vague. And so what can we do that is maybe better? Well, we can go back to the people. That's all, that's the best info available. That's it. Well, we can try and cross correlate it because while the astronomers in the ancient Holy Land were not quite up to the task. There were three sets of astronomers who were up to the task and really were doing their jobs on a night by night basis. And these are the imperial astrologers of China, Japan, and Korea.

50:53Okay. Who were looking at the sky every night as harbingers. Of anything, good or bad. Yeah. Good or evil. Yeah. Because clearly the gods were up there and the emperor was a demigod. So whatever was happening to the gods was affecting the emperor. So we'd better watch out really carefully and write down what was going on. And so from about 300 BC, but certainly from zero BC onwards, there are pretty good nightly records in all three kingdoms. And the star of 1054, the, what's today, the crab supernovas. The crab nebula. The crab nebula is detailed in great detail, wonderful detail in all three kingdoms records.

51:44Wow. So we know all about it. So we know that it took place. Took place. On July 4th, AD 1054. And astrophysicists to this day celebrate with fireworks. I just want you to. You see a launch of fireworks. That's what, that's what's going down. That's so funny. So you'd like to look for a. So they would have had records for sure. If there had been a really bright supernova or a really bright nova. Bright anything. Yeah, sure. A bright nova, a nova that's only say a hundred light years away. And there are stars that are capable of becoming novas only a hundred light years away. uh that is an easy star that can become brighter than venus so not quite a middle of the day scary you have to death brightness but still pretty bright pretty bright so you gotta go look really carefully at the chinese japanese and korean records from say minus 10 to plus 10 yeah um you know ad uh and there is no good candidate and there's no good yeah okay yeah Wow.

52:50And by the way, planetariums historically always had a Christmas show of the star of Bethlehem. And was it a planetary alignment? Was it Venus? Was it this? Was it that? And, but it really wasn't any of those. Right. And that's kind of a disappointing ending to a planetarium show. But we would, we got so sick of the show. I mean, it was just not, there was no science in it. Yeah. And so in the, in the, in the parlance of planetarium, you know what we call it? The war on Christmas? No.

53:18No, it was tradition. People come to see that and they go to the Rockettes. Right. And that was, that would be the holiday thing. That makes sense. No, but it became the SOB show. SOB standing for? Star Bethlehem. There you go. So we now have the technology. Astronomers now have the technology to once and for all answer the question. Okay. And I'm going to tell you how you heard it here first. All right. using the kind of telescope I described, the one that found the super shell. What question are we answering now? Was there a star? Starbett? Was there a transient? Was there a bright nova or supernova?

53:56Right. Within, say, 10 years of zero AD. Yes. And we can actually answer that question now quite definitively. And within five to 10 years, certainly within 10 years, we're going to be able to give you that answer quite definitively. Because you could. Because you are looking right now. Because if it was something that exploded, you'd be able to see the remnant that's 2 ,000 years old. And we're going to be able to track the expansion. Yes. And then track the expansion backwards. Right. To see when it went off. So you will know. You will know for a fact. Oh my gosh. And see, this is the cool thing about astrophysics because it comes with receipts.

54:35You know what I mean? You cannot bullshit. This is Cicero Artifon. What a cool name, Cicero. We've had Cicero before. Yeah, we've had them before. Unless there's more than one Cicero out there, but I doubt it. There ain't no true Cicero artiphons. That's for sure. Hi, Dr. Tyson, Dr. Shower Lord Nice. Cicero artiphon here from the cold lands of Toronto, Canada. We use these incredibly bright supernovae as standard candles to figure out how far away galaxies are. But it feels a bit counterintuitive, doesn't it? How can something so incredibly distant and that happened so long ago act as a reliable measuring tape for the cosmos?

55:18What's the ingenious method that allows us to use these far off stellar explosions to gauge such immense distances? That's a terrific question. These are the so-called type 1A supernovae. You weren't happy with just two types of supernovae, were you? We had to subtype and subtype. The type 1As are the magical supernovae that give us astronomers a yardstick. We want to know how far away something is so that we don't just see how bright it is, but how energetic it is. We can turn brightness into energy, into physical units. Right. And the type 1As are something that we call standard candles. or equivalently standard 100 watt light bulbs.

56:13They're not - Candles were quite honored that we used them in this reference. Yes, they did. It's very classical. Since they really suck as a light source, they should be honored, but go ahead. Well, the standard candle was made out of whale blubber. Whale blubber has a certain size. The oil lamps. Yeah, oil lamps. I take it back then because believe it or not, those actually burn pretty evenly in - Well, if you have a big enough wick. That was the point. The beautiful thing about type 1a supernovas is not that they are really all exactly the same intrinsic luminosity, but because we're able to measure the distances to some galaxies with other tools that we believe in very firmly, especially the Cepheid variable stars.

56:59and now the so-called tip of the red giant branch stars, we have a few hundred galaxies whose distances we know with great accuracy. Nearby. Nearby. Out to perhaps 50 million light years. That's nearby. Okay. 50 million light years. Far back. Far back. Let's go there tomorrow. And we see type 1a supernovas going off there, and we can measure their light curves, their brightness as a function of time very precisely. And then we put them on the same graph and we see that the brighter ones also last longer. But when we collapse them down to the same width, in other words, if we just shrink them digitally, both in brightness and in width, they all lie right on top of each other.

57:52So they are standardizable candles, standardizable hundred watt light bulbs. I like that. That makes, that's great. So the thing we can measure easily is how long they take to fade. Yeah. And then we use that, how long they take to fade information to crunch down the light curve onto the standard light curve. And then we can look at supernovas that are 10 or 20 times further away than the furthest Cepheid. And that's how we can step way outside our backyard. So it relies on the nearby calibrations basically to trust what the extrapolation is going to be. And then you get far enough out to say, good grief.

58:35We thought the Hubble constant meant that the universe was always expanding at the same rate. Everything is cool. It ain't so. We have a change. We have an acceleration in the expansion of the universe. Where did that come from? Who ordered it? Yeah. The so-called dark energy. Right. We have no idea what it is, why it's there, et cetera, et cetera. But it seems to be there. And that's because of the type 1A supernipos. Right, because you know, because of your standardizable candle system, that it works all the way out to here. It's just that when you got to that point beyond that, that's when things change.

59:19Well, something had to change because everything else going, coming from this point forward to us still works. Everything still works. The physics is fine. Physics works. But it allows us to implicate the universe and not the standard. Not the standard. Correct. That's the point. Correct. Yeah. That's amazing. And to answer the second part of the question, why does the, how did the universe figure out to do something like this? It turns out to be these wonderful white dwarfs, these collapsed objects actually have a maximum possible mass. They can't get more than about 1.4 times the mass of the sun.

59:58If they do, then the gravitational forces within cannot be resisted by any pressure force without. And so there is a magic number. they actually calibrate themselves for you. There you go. That's amazing. There you go. Oh my God, science is so crazy. I love it. No, no, think about it. Because if the white dwarf would blow up at different masses, you don't know what you're looking at. But everybody's blowing up at the same mass. It's just a little more complicated than that. But here's the one caveat. I was proud for a second. Because you can have two white dwarfs, a binary white dwarf, merge. and then you can be anywhere between 1.4 and 2.8 times the mass.

1:00:46Gotcha. That would still count as a 1A supernova? That'll still count as a 1A. And that's why you have brighter ones and fainter ones and shorter decay times and longer decay times, because you have the little guys at the 1.4 and the bright, bright guys at 2.8. Okay. Okay. And we've learned how to calibrate for that. Okay. Little extra complication. So that's happened since I've been in graduate school. I don't think we knew that back in my day. Nope. Right. Nope. Now, so my little contribution to this. Go ahead. Go ahead. I am last author on a paper. Okay. Last but not least. Last author on a paper.

1:01:26The first author was Brian Schmidt. Okay. Okay. Nobel Prize winner. Nobel Prize winner for co-discovering the dark energy. with supernova type 1A. I'm on one of his supernova papers where, very proud of this, it is a supernova whose light curve does not fit the light curve of other supernova that it's supposed to until you invoke the expanding universe time dilation on its light curve. There you go. And then when you de... Then when you mathematically remove the time dilation of the light curve, it falls right back on cue. Super cool. So you get its distance and its speed, which is receding, and that rate stretches out the light curve.

1:02:18And so it was the first paper to demonstrate that. And now it's a routine correction that you make. So let me just see if I got this right. The stretching of space is really what makes the difference. Yes, and the stretching of space also stretches the time. The time frame. The time frame. That's correct. That's why you smart, man. No, there's 15 other authors on it. Okay. They were all brave because the first time you publish something wildly different from what anyone else has ever seen, there's always this little nagging voice in the back of your mind. Did I screw up somewhere? Am I going to be a laughing stock?

1:03:01If this interesting result resulted me screwing up. Right. Right. Right. Because if it matched other results, you all couldn't have screwed up in the same way. Right. Right. Right. So just to be clear about the timing. So if you are receding. Right. And you're sending one pulse per second, let's say. But you're receding, the next pulse will not get to you after a second. It's a little longer. Exactly. Because you're now farther than when you had sent the first pulse. Right. And so that in a timed light curve will stretch out the light curve. That's all. No. And so this got corrected for, and there was.

1:03:35I mean, you say it like it's nothing, but I mean, that's pretty elegant if you think about it. It was. It was. And he went on and got a bunch of these and got the Nobel Prize, and that was it. Deservedly so. I didn't get an invitation to the Nobel Prize. Oh, wow. Listen, it's in the mail.

1:03:52Michael, I think we have to quit it there. Wow, that was great, man. I mean, you're such a good talker. We didn't get to as many questions as we might have. Sorry about that. But they were good questions. Yeah, they were great questions and great, great answers. And I learned a lot. So, well, this is, I don't, I can actually, tonight, when I take my edible, I can think about all of this. I can think about all of this and really just like marinate. Just before you do, though, I want you to check whether T-Core Borer has exploded. Oh, I'll do that first. You have to look out your window. First of all, check my neutrino detector.

1:04:28There you go. Otherwise, you may see three or four T-core bores when you look out the window. All right. Thanks, friend and colleague, Michael Shara. Great pleasure. Thank you. Chuck, good to have you, man. Always a pleasure. All right. This has been yet another episode of StarTalk Cosmic Queries, the exploding stars edition. Oh, yeah. Neil deGrasse Tyson, bidding you, as always, to keep looking up. Thank you.