Speaker 1: Welcome to Bedtime Astronomy. Explore the wonders of the cosmos
Speaker 1: with our soothing Bedtime Astronomie podcast. Each episode offers a
Speaker 1: gentle journey through the stars, planets, and beyond, perfect for
Speaker 1: unwinding after a long day. Let's travel through the mysteries
Speaker 1: of the universe as you drift off into a peaceful
Speaker 1: slumber under the night sky.
Speaker 2: I want you to try a little thought experiment with me.
Speaker 2: It's a bit of a terrifying one, but just just bear.
Speaker 3: With me for a second, Okay, I'm with you.
Speaker 2: Imagine you're standing out in a field. It's a clear night,
Speaker 2: the air is cold and crisp, maybe it's winter, and
Speaker 2: you're looking up at the constellation Oriyan the Hunter, you know,
Speaker 2: the one, three stars for the belt, the sword hanging down,
Speaker 2: and that big angry red start to shoulder Beetlegeez.
Speaker 3: Can't miss it, exactly.
Speaker 2: It's a fixture. It's been in our story since we
Speaker 2: started writing things down. It's a cosmic landmark, an anchor
Speaker 2: for humanity. Really. Now, I want you to keep your
Speaker 2: eyes on that red dot. Don't blink, just watch it.
Speaker 2: And then suddenly the light just cuts out. No explosion,
Speaker 2: no beautiful expanding cloud of gas, none of that supernova
Speaker 2: stuff that turns night into day for a few weeks.
Speaker 2: It's just it's there, and then it's not a hole
Speaker 2: in the sky, a hole in I don't know.
Speaker 3: In reality, it gives you a physical reaction just thinking
Speaker 3: about it. Yeah, it's unnerving.
Speaker 2: It is, isn't it. It feels fundamentally wrong. Everything we
Speaker 2: know about physics tells us that energy doesn't just disappear,
Speaker 2: you know, massive objects don't just vanish into thin air.
Speaker 2: If beetle Jews winked out of existence tonight, the panic
Speaker 2: wouldn't just be among astronomers, it would be existential. We
Speaker 2: feel like the universe just glitched, like a pixel in
Speaker 2: the simulation just went dead.
Speaker 3: It would absolutely challenge our very deep seated comfort with
Speaker 3: the permanence of the cosmos. I mean, we rely on
Speaker 3: the violent deaths of stars on supernovae to explain so
Speaker 3: much about well, about us, where the elements came from.
Speaker 3: But silence, silence is just is spooky.
Speaker 2: And yet silence is exactly what we're here to talk
Speaker 2: about today. Because this whole scenario, this impossible, terrifying, vanishing act,
Speaker 2: it's not hypothetical anymore. It actually happened.
Speaker 3: It did in a galaxy not so far away.
Speaker 2: It didn't happen to Beatlecheos, thank goodness for the sake
Speaker 2: of our night sky. But it happened to our next
Speaker 2: door neighbor. We're looking at a report that was released
Speaker 2: just yesterday, February twelfth, twenty twenty six. It was published
Speaker 2: in Science magazine with support from the Simonce Foundation, and
Speaker 2: it details the life and the very very sudden death
Speaker 2: of a star with well the distinctly unromantic name of
Speaker 2: M thirty one twenty fourteen DS.
Speaker 3: One, a name only a cataloger could love, for sure exactly.
Speaker 2: But you shouldn't let that barcode of a name fool you.
Speaker 2: This star is at the very center of a mystery
Speaker 2: that's been I mean, it's been nagging astrophysicists for decades.
Speaker 3: It is.
Speaker 2: We are talking about the case of the failed super nova.
Speaker 3: Which is a term that I think for most people
Speaker 3: just sounds like a complete oxy moron, a contradiction in term.
Speaker 2: It really does. When I hear supernova, my brain immediately
Speaker 2: goes to the most violent, explosive, ridiculously over the top
Speaker 2: event imaginable so how does one fail? Did it just
Speaker 2: trip over its own shoelaces on the way to the
Speaker 2: explosion in a.
Speaker 3: Way that's not a bad analogy. Kind of did, But
Speaker 3: the consequences of that trip are, well, they're just fascinating.
Speaker 3: What we're really discussing today is the clearest, most unambiguous
Speaker 3: observation humanity has ever made of a massive star collapsing
Speaker 3: directly into a black hole with no bang, no bang,
Speaker 3: no fireworks, just a star that got too heavy, gave
Speaker 3: up the ghosts, and crushed itself completely out of existence.
Speaker 2: So this report is essentially the autopsy of a silent death.
Speaker 2: And what's really incredible to me is the detective work
Speaker 2: involved here. I mean, we're talking about spotting a single
Speaker 2: star blinking out in a galaxy that contains a trillion stars, Yeah,
Speaker 2: located millions of light years away.
Speaker 3: It's the ultimate neil in a haystack. Yeah, except in
Speaker 3: this case, the needle suddenly decides to become invisible.
Speaker 2: Right, So today let's just walk through this whole investigation.
Speaker 2: We're gonna look at the victim, this star M thirty
Speaker 2: one twenty fourteen DS one. We're gonna look at the
Speaker 2: murder weapon, gravity, and then we have to look at
Speaker 2: the alibi, this new idea of stellar convection that explains
Speaker 2: why the star didn't just vanish instantly, but actually left
Speaker 2: behind this this ghostly fingerprint, and.
Speaker 3: That fingerprint, that a little bit of leftover glow. That's
Speaker 3: the key to the whole thing. It challenges a lot
Speaker 3: of our basic assumptions about how black holes are even born.
Speaker 2: Okay, so before we get into the you know, the
Speaker 2: nitty gritty physics at the collapse, let's just set the scene.
Speaker 2: We need to go to the Andromeda galaxy M.
Speaker 3: Thirty one, our big sister galaxy.
Speaker 2: Right, It's about two and a half million light years away,
Speaker 2: And I feel like we just gloss over that number
Speaker 2: way too often. When we say this star vanished in
Speaker 2: twenty sixteen, we.
Speaker 3: I mean the lights stopped arriving here in twenty.
Speaker 2: Sixteen, exactly. The actual event, the death of the star
Speaker 2: happened two and a half million years ago.
Speaker 3: Yeah, and Homo habilist was just sort of figuring out
Speaker 3: the whole stone tools thing on Earth. This star was
Speaker 3: already dying. We were watching a very very old cosmic rerun.
Speaker 2: That time delay always messes with my head okay, but
Speaker 2: let's talk about the star itself. M thirty one twenty
Speaker 2: fourteen DS one. This wasn't some minor player, was it.
Speaker 2: This was a big deal.
Speaker 3: Oh no, this was an absolute heavyweight. The paper categorizes
Speaker 3: it as a massive star, but more specifically, we're looking
Speaker 3: at something in the neighborhood of twenty solar.
Speaker 2: Masses twenty times the mass of our.
Speaker 3: Sun, twenty times, And in astrophysics, mass is destiny. There's
Speaker 3: no escaping it.
Speaker 2: It's everything.
Speaker 3: It is entirely destiny. A star like our Sun. It'll
Speaker 3: die pretty gently, it'll puff off its outer layers, it'll
Speaker 3: become a white dwarf. It's a quiet retirement. But when
Speaker 3: you get above say, eight, maybe ten times the mass
Speaker 3: of the Sun, you enter a totally different realm, the
Speaker 3: realm of violent deaths.
Speaker 2: These are the rock stars at the galaxy.
Speaker 3: They absolutely are. They live fast, they burn incredibly bright,
Speaker 3: and they die young and spectacular, and.
Speaker 2: Usually they die loud, very very loud.
Speaker 3: Usually, and M thirty one twenty fourteen DS one was
Speaker 3: one of the most luminous stars in the entire Andromeda Galaxy.
Speaker 3: If you were an astronomer observing M thirty one this
Speaker 3: star was it was basically shouting its presence at you.
Speaker 3: It was shining with the intensity of tens of thousands
Speaker 3: of our suns a real beacon.
Speaker 2: Okay, so it's a cosmic lighthouse, and it's twenty fourteen.
Speaker 2: The light from the star is hitting our telescopes. But
Speaker 2: it wasn't just any telescope watching it, was it. This
Speaker 2: is where the detective story gets really interesting. The main
Speaker 2: data came from a project called NEOWISE.
Speaker 3: Right, and Neo WISE is a fascinating instrument in and
Speaker 3: of itself. It's a space telescope from NASA. Originally its
Speaker 3: name was just WISE, the Wide Field Infrared Survey Explorer,
Speaker 3: and its whole job was to map the entire sky
Speaker 3: in infrared.
Speaker 2: Light, so in heat radiation.
Speaker 3: Basically exactly, it's seeing what our eyes can't. It's seeing
Speaker 3: the thermal glow of the universe. YE Now WISE ran
Speaker 3: out of its primary coolant years ago, which normally is
Speaker 3: a death sentence for an infrared telescope, but NASA very
Speaker 3: cleverly repurposed it realize it could still be used to
Speaker 3: hunt for near Earth objects, asteroids, comments that sort of thing.
Speaker 3: Hence the new name NEOWISE.
Speaker 2: So Its main job is hunting for asteroids that might
Speaker 2: be on a collision course with Earth.
Speaker 3: Primarily. Yes, it sweeps the sky over and over and
Speaker 3: over again, and it's looking for things that move or
Speaker 3: things that change brightness against the static background of stars.
Speaker 3: But here's the beautiful unintended consequence. Because it scans the
Speaker 3: entire sky repeatedly, it advertently created this massive time lapse
Speaker 3: movie of the universe. Wow, it wasn't specifically looking for
Speaker 3: a dying star in Andromeda. It just happened to be
Speaker 3: looking everywhere all the time.
Speaker 2: That's the real beauty of big data, isn't it. You
Speaker 2: end up catching things you weren't even fishing for. So
Speaker 2: this team, led by a researcher named Kishal A d
Speaker 2: they're digging through all this archival neowise data. What did
Speaker 2: they find? What's the timeline?
Speaker 3: So think construct what's called a light curve, which is
Speaker 3: really just a graph of the star's brightness over time.
Speaker 3: And from about twenty five to twenty thirteen, the star's
Speaker 3: pretty I mean, it's a massive bright object just doing
Speaker 3: its thing. But in twenty fourteen, its behavior.
Speaker 2: Starts to change, It starts to get brighter.
Speaker 3: It does specifically in the mid in for read bands,
Speaker 3: the star starts to glow more intensely. It's a definite uptick.
Speaker 3: You can think of it like a fever. The star
Speaker 3: is becoming unstable. It's sick.
Speaker 2: Is that unusual for a star that big? I thought
Speaker 2: they were kind of all little anyway.
Speaker 3: They are. That's a great point. Massive stars are notoriously cranky.
Speaker 3: They burp, they flare, they pulsate, So a little brightening
Speaker 3: on its own wouldn't be a huge red flag. But
Speaker 3: this brightening, it continued and it intensified until about twenty sixteen,
Speaker 3: and that is when the event happened, the vanishing act,
Speaker 3: the collapse. Between twenty sixteen and about twenty nineteen, the
Speaker 3: light from this star didn't just fade, It plummeted. I mean,
Speaker 3: we're talking about a drop in luminosity that is just
Speaker 3: catastrophic invisible light and in near and for red light,
Speaker 3: it effectively went to zero. It was gone.
Speaker 2: Okay. I want to clarify the terms here because the
Speaker 2: report makes a big deal about distinguishing between near and
Speaker 2: red and mid infrared. Why does that distinction matter so much?
Speaker 3: It's absolutely crucial to understanding the mystery. So near for red,
Speaker 3: is a wavelength that's very close to the visible red
Speaker 3: light our eyes can see. It's the kind of light
Speaker 3: that a very hot object like the surface of a
Speaker 3: star emits. Meat Infrared, on the other hand, is a
Speaker 3: much longer wavelength. It represents cooler temperatures. Think warm dust. Essentially,
Speaker 3: got it.
Speaker 2: So near infrared equals hot star. Mid infrared equals warm dust.
Speaker 3: That's the perfect mental shorthand. So in twenty sixteen, the
Speaker 3: hot star signal that's the visible light in the nearer infrared,
Speaker 3: it just switches off. It drops by a factor of ten.
Speaker 2: Thousand, ten thousand. That's not dimming, that's just it's gone.
Speaker 3: It went from being a stadium flood light to a
Speaker 3: single candle flame in the middle of a hurricane. By
Speaker 3: twenty twenty two, twenty twenty three, for all intents and purposes,
Speaker 3: the star was no more.
Speaker 2: You know, if I were an astronomer looking at that
Speaker 2: data for the first time, my first thought wouldn't be, oh,
Speaker 2: a black hole formed. My first thought would be did
Speaker 2: my telescope break.
Speaker 3: Or did satellite fly in front of the lens right?
Speaker 2: Or did a big cloud of space dust just drift
Speaker 2: in front of it?
Speaker 3: And the team had to rule out every single one
Speaker 3: of those possibilities. They checked for instrumental errors. They checked
Speaker 3: for what they call dust obscuration fins, where maybe the
Speaker 3: star just had a mass of boop and threw out
Speaker 3: a cloud a soot that temporarily hid it from view.
Speaker 2: But those would look different.
Speaker 3: They look very different. Doff clouds tend to dim the
Speaker 3: star in a particular way. They red in the light.
Speaker 3: They don't typically make the star disappear completely, and so
Speaker 3: so quickly this was different. This looked terminal.
Speaker 2: So to recap the timeline, we have a star that
Speaker 2: gets a fever. It brightens up in twenty fourteen, then
Speaker 2: in twenty sixteen it pulls the plug. By twenty twenty three,
Speaker 2: there's almost nothing left of it except this faint, ghostly
Speaker 2: glow in the mid infrared, the warm dust signal.
Speaker 3: Which tells us that something is still there. Yeah, but
Speaker 3: whatever it is, it's not a star anymore.
Speaker 2: Okay, So we have the body, well the lack of
Speaker 2: a body, the crime scene. But to really understand why
Speaker 2: this is such a big deal, why this got published
Speaker 2: in a major journal like Science, we have to talk
Speaker 2: about how a star of twenty solar mass is supposed
Speaker 2: to die because going out quietly is not usually on
Speaker 2: the menu.
Speaker 3: No, not at all. If you pick up any standard
Speaker 3: astrophysics textbook, you flip to the chapter on twenty solar
Speaker 3: mass stars, and that chapter ends with one word in
Speaker 3: big bold letters, supernova.
Speaker 2: Let's break down that mechanism, because I think most people
Speaker 2: have the general idea of star runs out of fuel,
Speaker 2: goes boom, but the actual mechanics of why it goes boom,
Speaker 2: that's the part that failed.
Speaker 3: Here, right, That's exactly where it feeled. So a star
Speaker 3: is this beautiful, delicate balancing act. We call it hydrostatic equilibrium.
Speaker 3: On one side, you have the relentless crushing force of gravity.
Speaker 3: It's pulling every single particle inward. It wants to crush
Speaker 3: the star into an infinitesimly small point. And on the
Speaker 3: other side, on the other side, you have the fusion
Speaker 3: engine in the core, the nuclear fire. It's generating a
Speaker 3: tremendous amount of outward pressure radiation pressure that holds up
Speaker 3: the ceiling. It's constantly pushing everything out, so it's like.
Speaker 2: A permanently inflated balloon, but the air inside is a
Speaker 2: continuous nuclear explosion.
Speaker 3: Precisely for millions of years. Those two forces are in
Speaker 3: a perfect tug of war. They're balanced. Now, massive stars
Speaker 3: are like they're like onions. In the core, they burn
Speaker 3: hydrogen to helium. When that runs out, the core shrinks
Speaker 3: and heats up and starts burning helium into carbon, then
Speaker 3: carbon into neon, neon into oxygen, oxygen into silicon. You
Speaker 3: get these layers upon layers of heavier and heavier element
Speaker 3: until you get to iron, until you hit the iron catastrophe.
Speaker 3: Iron is the end of the line. It's nuclear ash.
Speaker 3: You cannot fuse iron atoms together and get energy out
Speaker 3: of the process. In fact, it actually costs energy to
Speaker 3: fuse them. So the moment the core of the star
Speaker 3: turns to iron, the engine stops, the fusion furnace just
Speaker 3: turns off.
Speaker 2: The outward pressure vanishes.
Speaker 3: Instantly, the tug of war is over, and gravity wins,
Speaker 3: and it wins catastrophically. The core, which is about the
Speaker 3: size of the Earth but contains the mass of more
Speaker 3: than our Sun, collapses into something the size of a
Speaker 3: city action of a second. This is the core collapse.
Speaker 2: And this is where the neutrinos come in, right, Because
Speaker 2: I've read that the neutrinos are actually the real drivers
Speaker 2: of the explosion, not the collapse itself.
Speaker 3: They absolutely are. Yeah, they're the secret ingredient. When that
Speaker 3: core crushes down from a white dwarf density to a
Speaker 3: neutron star density, it releases an almost unimaginable flood of neutrinos.
Speaker 2: These are the little ghost particles that pass through everything.
Speaker 3: Normally, yes, a neutrino from the Sun can pass through
Speaker 3: light years of lead without interacting. But the density in
Speaker 3: this collapsing core is so beyond anything we can comprehend
Speaker 3: that even the neutrinos get trapped for just a moment,
Speaker 3: and in that moment they dump a massive amount of
Speaker 3: their energy into the layers of gas that are still
Speaker 3: falling inward.
Speaker 2: So the core collapses, it kind of bounces, it releases
Speaker 2: this wave of neutrinos, and that neutrino energy is what
Speaker 2: creates the shockwave that blows the rest of the star
Speaker 2: to Smotherenes.
Speaker 3: That is the successful supernova mechanism. That's the script. The
Speaker 3: shockwave rips through the star's outer layers, it energizes them.
Speaker 3: We see a brilliant flash of light that can outshine
Speaker 3: its entire galaxy and we get a beautiful expanding nebula
Speaker 3: left behind.
Speaker 2: But thirty one twenty fourteen DS one, it didn't do that.
Speaker 2: The shockwave apparently didn't make it out of the locker room.
Speaker 3: This is the heart of the failed supernova scenario. Yeah,
Speaker 3: imagine that shockwave is starting to move outward. It's got
Speaker 3: all this energy is trying to push its way out,
Speaker 3: but it's pushing against twenty sons worth of heavy gas
Speaker 3: that is falling inward at thousands of kilometers per second.
Speaker 2: It's like trying to stop a freight train with a
Speaker 2: leaf blower.
Speaker 3: That is a perfect analogy. The shockwave stalls. The ram
Speaker 3: pressure as we call it, of the infalling matter is
Speaker 3: just two immens. The shockwave creates a bit of a fizzle,
Speaker 3: maybe bubbles for a little bit, but ultimately it just
Speaker 3: gets overwhelmed. Gravity crushes it back down.
Speaker 2: So the explosion is it's suffocated before it's even born.
Speaker 3: Exactly. It's an engine that stalls on the launch pad,
Speaker 3: and all that material that was supposed to be ejected
Speaker 3: into space to form a nebula, it just keeps falling.
Speaker 3: It falls back onto the newly formed neutrons star in
Speaker 3: the center and that's too much mass, way too much mass. Yeah,
Speaker 3: the neutron star crosses its stability limit it's called the
Speaker 3: Tolmann Oppenheimer volkof limit if you want to get technical,
Speaker 3: and it can no longer support itself against its own gravity.
Speaker 3: It collapses further a black hole. The event horizon forms,
Speaker 3: the star swallows itself whole.
Speaker 2: Wow, that is that's a grim way to go. It's
Speaker 2: a cosmic suffocation.
Speaker 3: It really is. And for a very long time this
Speaker 3: was just a theory. It was something we saw in
Speaker 3: computer simulations. The math would sometimes say, hey, for a
Speaker 3: star of this particular mass and this rotation rate, the
Speaker 3: shockwave shouldn't make it out, But we had never definitively
Speaker 3: seen it happen.
Speaker 2: We see the black holes that are leftover, and we
Speaker 2: see the supernovae, but capturing the moment of transition.
Speaker 3: That's the holy grail of this field and.
Speaker 2: One fourteen DS one is that holy grail. It's the
Speaker 2: missing link. It's the footage of the crime as it happened.
Speaker 3: It connects the dots. It proves observationally that you do
Speaker 3: not need a spectacular visible explosion to create a dollar
Speaker 3: mass black hole.
Speaker 2: But Hold on a second. This brings us to the
Speaker 2: twist in the plot. And this is the part of
Speaker 2: the Simons Foundation report that really gets into the new physics.
Speaker 3: Right, the problem of the lingering light.
Speaker 2: Yes, if the star just collapsed directly into a black hole,
Speaker 2: if the shockwave failed, why did we see anything at all?
Speaker 2: Why did it brighten back in twenty fourteen? And more importantly,
Speaker 2: why is there still an infrared glow there right now?
Speaker 2: If it's a black hole, shouldn't it just be dark?
Speaker 3: It's a fantastic question. That's the one that stumped people
Speaker 3: for a while. If the collapse were perfectly spherical, if
Speaker 3: the star were just a perfectly still, non rotating ball
Speaker 3: of gas, it would have just blinked out, gone in milliseconds,
Speaker 3: end of story. But stars aren't motionless. They spin, They spin,
Speaker 3: and they churn. The report puts a huge emphasis on
Speaker 3: the roll of convection.
Speaker 2: Okay, so let's unpack convection in this context. I know
Speaker 2: convection from you know, boiling a pot of water on
Speaker 2: the stove. Hot stuff rises, cool stuff sinks, it creates
Speaker 2: a current.
Speaker 3: It's the exact same principle, just on a nuclear egalactic scale.
Speaker 3: The eider. Layers of a massive star like this a
Speaker 3: red supergin, are very loosely bound. They're boiling violently. You
Speaker 3: have these giant cells of hot plasma, some of them
Speaker 3: larger than our entire sun, that arise into the surface,
Speaker 3: cooling and then sinking back down.
Speaker 2: That's incredible.
Speaker 3: It's a chaotic, turbulent environment. But crucially, all of that
Speaker 3: churning motion preserves angular momentum.
Speaker 2: This is high school physics coming back to haunt me.
Speaker 2: Angular momentum.
Speaker 3: That's the ice skater analogy, right, That is the classic
Speaker 3: perfect analogy. An ice skater is spinning with her arms
Speaker 3: stretched out. She pulls her arms in close to her body,
Speaker 3: and what happens.
Speaker 2: She spins way faster.
Speaker 3: She spins much much faster. That's the conservation of angular momentum.
Speaker 3: You can't just create or destroy that spin. It has
Speaker 3: to go somewhere.
Speaker 4: Okay.
Speaker 3: Now apply that exact same principle to the collapsing star.
Speaker 3: You have all this churning gas way out in the
Speaker 3: star's envelope. As gravity starts to pull it inward toward
Speaker 3: the newly formed black hole, It's like a skater pulling
Speaker 3: our arms in. That gas starts to spin incredibly fast.
Speaker 2: It speeds up as it falls.
Speaker 3: It speeds up so much that it eventually hits what
Speaker 3: we call a centrifical barrier. It's just spinning too fast.
Speaker 3: The centrifical force pushing outwards starts to fight against the
Speaker 3: gravity pulling inward, so the gas can't fall straight into
Speaker 3: the black hole.
Speaker 2: It gets backed up like a traffic jam.
Speaker 3: It forms an accretion disc, it goes into orbit. And
Speaker 3: this is where the report uses an analogy that I
Speaker 3: think is just brilliant. It comes from one of the researchers,
Speaker 3: Andrea and Tony at the Flat Iron Institute.
Speaker 2: The bathtub analogy.
Speaker 3: The bathtub imagine a tub full of water. If the
Speaker 3: water's perfectly still and you pull the plug, what happens?
Speaker 2: It just glugs straight down. It drains pretty quickly.
Speaker 3: Right, that's a direct collapse without any rotation.
Speaker 4: Yeah.
Speaker 3: But if you get your hand in there and swirl
Speaker 3: the water first, give it some angular momentum, and then you.
Speaker 2: Pull the plug, ah, it creates a vortex, a whirlpool.
Speaker 2: It circles the drain, and crucially.
Speaker 3: It takes a whole lot longer to empty the tub,
Speaker 3: doesn't it If the water has to lose that spin,
Speaker 3: that angular momentum through friction before it can actually fall
Speaker 3: down the hole.
Speaker 2: So the star thirty one twenty fourteen DS one is
Speaker 2: a cosmic bathtub slowly draining into a black hole.
Speaker 3: That's it. The water is the stellar plasma, the drain
Speaker 3: is the black holes event horizon, and the swirling vortex
Speaker 3: is the hot, glowing accretion disk.
Speaker 2: And the swirling explains the light, the glow that's left over.
Speaker 3: It explains everything. First, friction, when you have gas scrolling
Speaker 3: around that fast, rubbing against other layers of gas, it
Speaker 3: generates an immense amount of heat. We are talking about
Speaker 3: friction on a scale that releases X rays and a
Speaker 3: ton of thermal energy.
Speaker 2: So the drain itself is glowing.
Speaker 3: The water circling the drain is glowing. But there's a second,
Speaker 3: really important part to this mechanism. The energy from that friction,
Speaker 3: from that hot disk, it doesn't just sit there, It
Speaker 3: pushes back. It actually provides enough energy to drive some
Speaker 3: of the outermost material away from the star.
Speaker 2: Wait, so the very act of feeding the black hole
Speaker 2: actually makes the star kind of vomit some of its
Speaker 2: material back out.
Speaker 3: That's a violent, but very accurate way of putting it, it
Speaker 3: ejects its outermost, most loosely bound envelope of gas. This
Speaker 3: gas expands out into space away from the black hole.
Speaker 3: And as any gas expands, what does it do?
Speaker 2: It cools down.
Speaker 3: It cools down, and as it cools it crosses a
Speaker 3: critical temperature threshold, a point where individual atoms of things
Speaker 3: like silicon and carbon can finally slow down enough to
Speaker 3: stick together. They form solid grains, They form dust, cosmic
Speaker 3: dust sut essentially.
Speaker 2: Okay, let me see if I have the full picture here,
Speaker 2: because this is amazing. The core collapses, the big explosion fails,
Speaker 2: a black hole is born in the center. The outer
Speaker 2: layers of the star try to fall in, but they're
Speaker 2: spinning two fat so they form a hot, glowing disc
Speaker 2: around the black hole, like water down and drain.
Speaker 3: Yep, you've got it.
Speaker 2: That hot disk then flings some of the very outermost
Speaker 2: material away from the whole system, and that ejected material
Speaker 2: flies outward, cools down, and condenses into a giant shell
Speaker 2: of dust.
Speaker 3: A perfect summary.
Speaker 2: And that dust shell that's the curtain. That's what hides
Speaker 2: the star.
Speaker 3: That's the curtain. Dust is incredibly effective at blocking visible
Speaker 3: and near infrared light. It absorbs it and scatters it.
Speaker 3: That is why the star vanished in twenty sixteen. The
Speaker 3: dust shell basically hid the scene of the crime. But
Speaker 3: and here's the absolute key to the infrared signal. Dust
Speaker 3: gets warmed up. It absorbed the intense heat coming from
Speaker 3: that inner engine, that hot accretion disk, and it reradiates
Speaker 3: that heat.
Speaker 2: It glows in the dark.
Speaker 3: It glows in the mid infrared. The dust shell is
Speaker 3: acting like a lamp shade. You can't see the blindingly
Speaker 3: bright light bulb the hot accretion disk directly anymore, but
Speaker 3: you can see the warm, gentle glow of the lamp
Speaker 3: cade surrounding it.
Speaker 2: Wow. That is such a satisfyingly complete explanation. It ticks
Speaker 2: every single box in the data. The brightening in twenty
Speaker 2: fourteen was the star becoming unstable, the initial belch the
Speaker 2: vanishing was the dust curtain forming. And the faint low
Speaker 2: we see now is the warm lamp shade powered by
Speaker 2: the swirling drain underneath.
Speaker 3: And it turns what was just a weird, confusing event
Speaker 3: into a clear physics lesson. It tells us that these
Speaker 3: massive stars don't just turn off even in failure. Their
Speaker 3: deaths are incredibly dynamic, chaotic, and well messy processes.
Speaker 2: So this brings us to the timescale of it all,
Speaker 2: which the report calls the long goodbye you mentioned The
Speaker 2: bathtub analogy explains why it takes longer to drain. How
Speaker 2: much longer are we talking?
Speaker 3: So if it were a simple freefall, a direct collapse
Speaker 3: with no rotation, the whole thing would be over in
Speaker 3: a matter of months, maybe a year at most, the
Speaker 3: star would be gone. Because of the angular momentum, the
Speaker 3: viscous time scale, as it's called, takes over. The material
Speaker 3: has to slowly lose its spin through friction, and that
Speaker 3: process it'll take decades.
Speaker 2: Decades we're still watching it happen.
Speaker 3: Oh yeah, we will be watching this star slowly drain
Speaker 3: for the rest of our scientific careers. Andrea and Tony,
Speaker 3: the researcher i mentioned, actually calculated the accretion rates. It's
Speaker 3: a very slow feed. The black hole is just sipping
Speaker 3: at the material, not gulping it.
Speaker 2: And how much of the star actually makes it down
Speaker 2: the drain in the end, that's one of.
Speaker 3: The most surprising parts of the simulation results. Their calculation
Speaker 3: suggests that only about one percent of the star's original
Speaker 3: outer envelope actually falls into the black hole during this
Speaker 3: initial bright phase.
Speaker 2: Only one percent. That seems incredibly inefficient.
Speaker 3: It turns out black holes can be very messy eaters.
Speaker 3: That angular momentum barrier is really really effective at keeping
Speaker 3: material out. The vast majority of the star's outer layers
Speaker 3: are either ejected into the interstellar medium forever or they'll
Speaker 3: hang out in a much larger, cooler disc for thousands
Speaker 3: of years. But that tiny one percent, that's more than
Speaker 3: enough to power the infrared glow that we're seeing today.
Speaker 2: So M thirty one twenty fourteen DS one is essentially
Speaker 2: a ghost. It's a black hole wearing the dusty corpse
Speaker 2: of its parents star like a like a shroud or
Speaker 2: a disguise.
Speaker 3: That is a very metal way to put it. But yes,
Speaker 3: fundamentally that is what we are looking at.
Speaker 2: I try. But this leads to the bigger question. Right,
Speaker 2: you mentioned this is a Rosetta stone. It helps us
Speaker 2: translate the data from this one event. Does this help
Speaker 2: us find others? Or is this starts a complete freak accident,
Speaker 2: a cosmic oddball.
Speaker 3: And that's probably the most important takeaway from a scientific perspective.
Speaker 3: This is almost certainly not unique. In fact, as soon
Speaker 3: as the team understood the pattern, they were looking at
Speaker 3: the signature of brighton then vanished, then lead behind an
Speaker 3: infrared glow. They did what any good detective would do.
Speaker 2: They went back and looked at some old cold cases.
Speaker 3: Exactly. They re examined a different star, another one with
Speaker 3: a bar code name, and GC six' nine four six bh.
Speaker 2: One rolls right off the.
Speaker 3: Tongue this one is in a different, galaxy The fireworks,
Speaker 3: galaxy which is about twenty two million light years. Away
Speaker 3: back in two thousand and, nine this star did something
Speaker 3: very very. Similar it suddenly brightened up to about a
Speaker 3: million times The sun's, luminosity and then it just vanished from.
Speaker 2: Sight and what do they call it at the, Time.
Speaker 3: At the, time astronomer was just called it a red.
Speaker 3: Transient they debated it. Endlessly no one could. Agree was
Speaker 3: it a failed? Supernova was it two stars more? Together
Speaker 3: was it some weird type of eruption we'd never seen.
Speaker 3: Before the data was ambiguous, now but now FOURTEEN ds
Speaker 3: one provides the. Template it provides the. Key they look
Speaker 3: back at the old data for that star and the
Speaker 3: light curve the timeline of. Events it matches almost. Perfectly
Speaker 3: it's the same. SIGNATURE ngc six x nine four SIX
Speaker 3: bh one was also a failed. Supernova we just didn't
Speaker 3: have the high resolution infrared data and the sophisticated models
Speaker 3: to confirm the mechanics back.
Speaker 2: Then so we're starting to build a family tree of these.
Speaker 2: Things we're defining a new.
Speaker 3: Category we are defining a new class of stellar. Death
Speaker 3: and this has huge implications for, well for our census
Speaker 3: of black holes in the.
Speaker 2: Universe how, so what does it?
Speaker 3: Change, well think About ligo And, virgo the gravitational wave.
Speaker 3: Detectors for the past, decade they've been detecting the mergers
Speaker 3: of black, holes and a consistent puzzle has been that
Speaker 3: many of these black holes are surprisingly. Massive we're seeing
Speaker 3: them at, thirty, forty even fifty times the mass of The.
Speaker 2: Sun and that's been a, problem right because if a
Speaker 2: star explodes as a regular, supernova it blows a lot
Speaker 2: of its own mass away in the. Explosion it shouldn't
Speaker 2: be able to leave behind such a heavy black.
Speaker 3: Hole, exactly if you're a sixty solar mass star and
Speaker 3: you blow off half your mass in a spectacular, explosion
Speaker 3: you can't leave behind a fifty solar mass black. Hole
Speaker 3: the math just doesn't. Work but if you are a failed, supernova.
Speaker 2: You don't blow anything. Off you keep all of the.
Speaker 3: Masks you keep almost all of. It if the star
Speaker 3: just collapses and swallows its own, envelope the resulting black
Speaker 3: hole is much much. Heavier this, mechanism the silent, death
Speaker 3: might just be the missing production line for all of
Speaker 3: these unexpectedly massive black holes That lego has been.
Speaker 2: Seeing that connects the dots on a cosmological. Scale the
Speaker 2: silence we're seeing here explains the gravity waves we're detecting
Speaker 2: from across the.
Speaker 3: Universe it really. Does it suggests that failing to explode
Speaker 3: is actually a very successful way to build big black.
Speaker 2: Holes you, know this brings us to the more existential
Speaker 2: part of this whole, conversation and, honestly this is the
Speaker 2: part that kind of keeps me up.
Speaker 3: At, night the silent universe.
Speaker 2: Idea, yeah we have built our entire understanding of the
Speaker 2: cosmos on the things we can, see the blight, lights
Speaker 2: the loud. Bangs we literally count the number of supernova
Speaker 2: we see to estimate how fast galaxies are forming. Stars
Speaker 2: we use a certain type of supernova as standard candles
Speaker 2: to measure the expansion of the universe.
Speaker 3: Itself we are fundamentally biased toward the loud and the.
Speaker 2: Bright but what, if what if we're missing half the?
Speaker 3: Picture that is the big profound question The Cachelai day
Speaker 3: and his team are. Posing if a significant fraction of massive,
Speaker 3: stars maybe it's ten, percent maybe it's thirty, percent we
Speaker 3: don't know, yet if they die in, silence that our
Speaker 3: entire census of the universe is.
Speaker 2: Wrong it's like trying to count the population of a
Speaker 2: city by only counting the people who are screaming at
Speaker 2: the top of their.
Speaker 3: Lungs that is a perfect. Analogy we have been completely
Speaker 3: ignoring the quiet. Ones and this has other consequences. Too
Speaker 3: it changes the chemical evolution of a. Galaxy supernovae are
Speaker 3: the great. Dispersers they forge heavy elements in their, cores
Speaker 3: the oxygen you're, breathing the calcium in your, bones and
Speaker 3: then they spread that material throughout the galaxy to be.
Speaker 2: Used in the next generation of stars and.
Speaker 3: Planets but if these stars don't, explode they lock all
Speaker 3: those precious heavy elements away inside black holes event horizon.
Speaker 2: Forever they hoard, them they take them out a, Circulation.
Speaker 3: They completely remove them from the cosmic. Ecosystem so the
Speaker 3: rate of failed supernovae directly determines how much stuff is
Speaker 3: available in a galaxy to make planets and eventually to make.
Speaker 3: People so the story OF.
Speaker 2: M thirty one twenty FOURTEEN ds one isn't just a
Speaker 2: weird astronomical. Curiosity it's variable in the equation of. Life
Speaker 2: it really, is and it makes you, wonder you, know
Speaker 2: about things like The fermi, paradox where is? Everybody maybe
Speaker 2: the universe is just darker and quieter than we thought it.
Speaker 2: Was maybe advanced civilizations get swallowed in the dark along
Speaker 2: with their home stars and we just never see the.
Speaker 3: Flash oh that's a that's a dark. Turn but let
Speaker 3: me offer a more hopeful. Counterpoint. Technology the only reason
Speaker 3: we found this event is because we had the right
Speaker 3: kind of. Eyes we Had neo, wise which could see
Speaker 3: in the. Infrared we have The James Webb Space telescope,
Speaker 3: now which is even more. Powerful we are for the
Speaker 3: first time developing the sensory organs to perceive the dark
Speaker 3: parts of the.
Speaker 2: Universe we're evolving our ability to.
Speaker 3: See we're learning to see the, shadows AND i think
Speaker 3: that's incredibly. Hopeful we're finally realizing that the absence of
Speaker 3: light is also a form of, information a very powerful.
Speaker 2: One the absence of light is. INFORMATION i love. That
Speaker 2: it's Very Sherlock. Holms you, know the curious incident of
Speaker 2: the dog in the. Nighttime what the dog did nothing
Speaker 2: in the? Nighttime that was the curious incident exactly.
Speaker 3: Thirty one twenty. FOURTEEN ds one is the star that didn't.
Speaker 3: Bark and because we finally noticed the, silence we learned
Speaker 3: something fundamental about how a black hole is.
Speaker 2: Born so as we kind of wrap this all, UP
Speaker 2: i want to go back to that image of the,
Speaker 2: bathtub the swirling, water the. Drain it's such a, mundane
Speaker 2: everyday image for something so catastrophic and so, Cosmic.
Speaker 3: But that's the beauty of. It physics is. Universal the
Speaker 3: same principles of fluid dynamics and angular momentum that drain
Speaker 3: your tub after a bath also govern the death of
Speaker 3: a sun two and a half million light years.
Speaker 2: Away that is either strangely comforting or deeply. TERRIFYING i
Speaker 2: haven't quite decided which.
Speaker 3: Yet, WELL i. Both booth is.
Speaker 2: Good so the big takeaways for everyone listening, today what
Speaker 2: should they remember from all?
Speaker 3: THIS i think first massive stars don't always. Explode sometimes
Speaker 3: they just they give up the ghost and. Collapse, second
Speaker 3: this collapse is an. Instant it's a messy. Process convection
Speaker 3: and the star zone spin create this, swirling dusty death
Speaker 3: spiral that takes decades to. Unfold so it's a long.
Speaker 3: Goodbye it's a very long. Goodbye, third we can actually
Speaker 3: see this, happen but only if we look in the
Speaker 3: right kind of light in the. Infrared the dust hides
Speaker 3: the visible, star but that same dust glows with. Heat and,
Speaker 3: finally and maybe most, importantly the universe might be full
Speaker 3: of these stellar ghosts and we are only just now
Speaker 3: learning how to look for.
Speaker 2: THEM a universe full of. Ghosts i'm definitely going to
Speaker 2: be thinking about that the next TIME i look up
Speaker 2: At oryan's.
Speaker 3: Shoulder just to keep a close eye on beetlegars for.
Speaker 2: ME i, will and if it blinks, out you are
Speaker 2: the first Person i'm.
Speaker 3: Calling i'll be waiting for the.
Speaker 2: Call thank you so much for walking us through, this
Speaker 2: and thank you all for listening to this investigation into the.
Speaker 2: Dark it's just a reminder that sometimes the biggest discoveries
Speaker 2: happen not with a, bang but in the, silence so
Speaker 2: keep looking up and don't be afraid of the.
Speaker 4: Dark goodbye, everyone set pass school