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: Imagine for a second, you're just looking up at the
Speaker 2: night sky, right right, just taking it in. Yeah, and
Speaker 2: you're watching one of the absolute brightest street lights in
Speaker 2: the entire universe simply turn off, just completely go dark exactly.
Speaker 2: And I don't mean fading away over millions of years
Speaker 2: as the cosmos slowly ages. I mean we are talking
Speaker 2: about a beacon so luminous that it outshines entire galaxies
Speaker 2: oh easily, and it dims so incredibly fast that you
Speaker 2: actually witness it happen within a fraction of your own lifetime.
Speaker 3: It's it really is a staggering image, and I think
Speaker 3: it fundamentally breaks how we are taught to perceive the cosmos, right,
Speaker 3: because we're basically conditioned to view the universe as this
Speaker 3: static painting.
Speaker 2: Yeah, Like it's unchanging exactly.
Speaker 3: We just assume that astronomical changes happen on these massive
Speaker 3: time scales that render a single human life practically invisible.
Speaker 2: A blink of an eye, right, But.
Speaker 3: The event we're gysecting today it proves that assumption completely
Speaker 3: undeniably wrong.
Speaker 2: And that is exactly our mission today. We are taking
Speaker 2: a journey roughly ten billion light years across the universe
Speaker 2: to explore a cosmic anomaly that is frankly forcing astrophysicists
Speaker 2: to rewrite the entire rule book.
Speaker 3: Yeah, they really are.
Speaker 2: We are investigating the sudden, dramatic and honestly pretty violent
Speaker 2: dimming of a very distant galaxy.
Speaker 3: Violent is definitely the right word for it.
Speaker 2: And by the time we're done here, you'll understand the
Speaker 2: intricate machinery that powers the brightest objects in the cosmos.
Speaker 3: Which is fascinating in itself.
Speaker 2: Oh absolutely. Plus you'll see how astronomical cold case detectives
Speaker 2: essentially use seventy year old evidence to solve modern mysteries.
Speaker 3: I love that part of the story.
Speaker 2: It's so good. And we'll get into why everything we
Speaker 2: thought we knew about the life span of supermassive black
Speaker 2: holes might just need to be thrown right out the window.
Speaker 3: Yeah, because to really appreciate the shockwave, this scent through
Speaker 3: the astrophysics community, we first have to, well, we have
Speaker 3: to establish the scene of the cosmic crime, so to speak.
Speaker 2: Right, let's set the stage. Where are we looking?
Speaker 3: So the focus is this specific incredibly distant galaxy. It's
Speaker 3: cataloged is JA zero two one eight minus serio zero
Speaker 3: three at six. Patchy name, very catchy, right, standard astronomical naming.
Speaker 3: But astronomers measure the distance to these far off objects
Speaker 3: using a metric called red shift. Okay, and Jay zero
Speaker 3: two one eight has a red shift of one point eight.
Speaker 2: Let's actually break down what a red shift of one
Speaker 2: point eight actually means, because you know, it's not just
Speaker 2: a physical distance.
Speaker 3: Right, It's not just miles or coldometers.
Speaker 2: No, it's a temporal distance. It's time because light takes
Speaker 2: time to travel. Looking across space is quite literally looking
Speaker 2: back in time, cosmic time machine exactly. It's like receiving
Speaker 2: a postcard in the mail that took ten billion years
Speaker 2: to arrive.
Speaker 3: That's a great way to put it.
Speaker 2: And the unsettling part is, as you're holding this ancient
Speaker 2: postcard in your hands, the picture on the front drastically
Speaker 2: fades right before your eyes.
Speaker 3: Yeah. That temporal aspect is so vital to understand because
Speaker 3: when we observe the light from j zero to le eight,
Speaker 3: we are seeing the universe as it was when it
Speaker 3: was only roughly a third of its current age.
Speaker 2: Wow, only a third.
Speaker 3: Yeah, this era around a redshift of two. Astronomers often
Speaker 3: referred to it as cosmic noon.
Speaker 2: Cosmic noon. That sounds intense.
Speaker 3: It was. It was this period of intense rapid star formation.
Speaker 3: Galaxies were incredibly active, chaotic, constantly colliding and merging.
Speaker 2: So finding a tremendously bright object in that specific era
Speaker 2: isn't really the surprise, right.
Speaker 3: Not at all. We expect things to be bright and
Speaker 3: violent back then. The shot came when an international team
Speaker 3: led by Tomochi Morrikuma at the Cheap Institute of Technology,
Speaker 3: when they discovered that the brightness of jayas zero two
Speaker 3: to ODA suddenly plummeted to just one twentieth of its
Speaker 3: original level. We're twentieth And the craziest part, it did
Speaker 3: this in merely twenty earth years see a.
Speaker 2: Twenty full drop. I mean that means we are looking
Speaker 2: at a system that went from operating at peak luminosity
Speaker 2: down to just five percent of its previous output five percent.
Speaker 2: If you're say, driving to work right now, think about
Speaker 2: the engine in your car. Okay, if your engine suddenly
Speaker 2: lost ninety five percent of its power, you wouldn't just
Speaker 2: call it a minor fluctuation.
Speaker 3: No, you'd pull over immediately, right.
Speaker 2: You would assume a catastrophic mechanical failure.
Speaker 3: That is a highly accurate way to frame it, actually,
Speaker 3: because an object visible from ten billion light years away
Speaker 3: is generating energy on a scale that completely defies everyday comprehension.
Speaker 3: It's unfathomable, truly, So to lose ninety five percent of
Speaker 3: that ma massive energy output in just two decades, it
Speaker 3: signals a complete systemic breakdown of the engine driving that light.
Speaker 2: Which brings us to the mechanics of the engine itself,
Speaker 2: because a twenty fold drop in brightness is massive. But
Speaker 2: to grasp the true scale of what was lost, we
Speaker 2: really need to understand what was generating all that light
Speaker 2: in the first place.
Speaker 3: Right, what's the fuel? What's the engine?
Speaker 2: Yeah, because we are just talking about a really big
Speaker 2: cluster of stars here, No, definitely not. We are talking
Speaker 2: about an active galactic nucleus or an agn Yeah, so.
Speaker 3: If we look at the anatomy of most large galaxies,
Speaker 3: including our own, actually we find a supermassive black hole
Speaker 3: right at the core.
Speaker 2: And when we say super massive, we are.
Speaker 3: Talking about an object with a mass of hundreds of millions,
Speaker 3: sometimes billions of times the mass of our own sun.
Speaker 2: Just compact it into a tiny point.
Speaker 3: Exactly, compacted into a relatively tiny region of space. Now,
Speaker 3: in a quiet galaxy like our Milky Way, the black
Speaker 3: hole is mostly dormant right sitting there, Yeah, it's fasting.
Speaker 3: But in an active galactic nucleus, the environment is violently chaotic.
Speaker 3: You have these immense clouds of gas and dust constantly
Speaker 3: being pulled inward by the black hole's gravity.
Speaker 2: But wait, knowing the engine is powered by a black
Speaker 2: hole makes this whole scenario sound incredibly counterintuitive to me.
Speaker 2: How so, Well, we all know the fundamental rule of astrophysics, right,
Speaker 2: nothing escapes the event horizon, right, not even light exactly.
Speaker 2: Black Holes are the ultimate cosmic vacuum cleaners. They trap light.
Speaker 2: So how is it that the area immediately surrounding the
Speaker 2: darkest object in the universe somehow becomes the brightest thing
Speaker 2: we can possibly see.
Speaker 3: It is honestly one of the most beautiful paradoxes in physics.
Speaker 2: I mean, is it purely just the friction of some
Speaker 2: cosmic traffic gem.
Speaker 3: That's a huge part of it. The key is really
Speaker 3: differentiating the black hole itself from its surrounding environment.
Speaker 2: Okay, separate the hole from the waiting room exactly.
Speaker 3: The event horizon is the boundary of no return. But
Speaker 3: the light we see from an agn isn't coming from inside.
Speaker 2: The black hole, obviously not because we wouldn't see it.
Speaker 3: Right, It's coming from the accretion disc, that is, the
Speaker 3: waiting room of material just outside the event horizon.
Speaker 2: So what's happening in that waiting room?
Speaker 3: Well, as gas is pulled inward, conservation of angular momentum
Speaker 3: forces it to swirl around.
Speaker 2: The black hole, kind of like water circling a drain.
Speaker 3: Exactly like that, right, And it flattens out into this vast,
Speaker 3: incredibly dense whirlpool of plasma.
Speaker 2: And as that plasma spirals closer and closer to the
Speaker 2: event horizon, it accelerates massively.
Speaker 3: The inner tracks of this whirlpool are spinning at a
Speaker 3: significant fraction of the speed of light. Wow. Meanwhile, the
Speaker 3: outer tracks are moving much much slower.
Speaker 2: Ah. Okay, so the inner lanes of the highway are
Speaker 2: moving at near light speed and the outer lanes are sluggish.
Speaker 3: Yes, And that differential rotation creates something we rarely associate
Speaker 3: with the vacuum of space, which is profound.
Speaker 2: Friction because things are rubbing together.
Speaker 3: But it's not the simple mechanical friction of two solid
Speaker 3: objects rubbing together, like rubbing your hands to get warm.
Speaker 2: Right, because it's gas.
Speaker 3: Well, it's plasma. They're dealing with plasma physics here, So
Speaker 3: the friction is actually driven by magnetic fields threading through
Speaker 3: this ionized gas.
Speaker 2: Oh interesting.
Speaker 3: Yeah, As these layers of plasma sheer against each other
Speaker 3: at relativistic speeds, it triggers a phenomenon called magnetor rotational.
Speaker 2: Instability magneto rotational instability.
Speaker 3: That sounds like a mouthful it is, but basically it
Speaker 3: just creates immense violent turbulence within the disk, okay. And
Speaker 3: that turbulence is what converts the gravitational potential energy of
Speaker 3: the in falling gas into staggering amounts of heat.
Speaker 2: So we aren't just talking about the gas getting a
Speaker 2: little warm, no, No.
Speaker 3: The friction generated by these magnetic turbulent forces, heats the
Speaker 3: plasma to hundreds of thousands, sometimes millions of degrees.
Speaker 2: Millions of degrees.
Speaker 3: That is insane, and at those extreme temperatures, the gas
Speaker 3: glows brilliantly across the entire electromagnetic spectrum.
Speaker 2: So it's basically screaming as it falls in.
Speaker 3: Exactly, it's the death cry of the gas just before
Speaker 3: it crosses the event horizon. And the efficiency of this
Speaker 3: process is difficult to overstate.
Speaker 2: How efficient is it compared to say, a star.
Speaker 3: It's wildly more efficient. Dropping mass into a supermassive black
Speaker 3: hole via an accretion disc is actually one of the
Speaker 3: most efficient ways to generate energy in the known universe.
Speaker 2: Wait, really more than fusion.
Speaker 3: Far more efficient than the nuclear fusion powering stars like
Speaker 3: our sun.
Speaker 2: I had no idea.
Speaker 3: Yeah, that is exactly why a single agn can outshine
Speaker 3: hundreds of billions of stars combined.
Speaker 2: Okay, so we have established this blindingly bright vortex of
Speaker 2: superheated plasma rueled by the immense gravity of a monster
Speaker 2: black hole pumping out more energy than entire galaxies.
Speaker 3: That's the engine.
Speaker 2: But knowing that the engine is a massive accretion disc
Speaker 2: makes this rapid shut down even more impossible to believe
Speaker 2: it really does, because we are talking about physical structures
Speaker 2: that are light years cross right.
Speaker 3: Sometimes yes, they are immense.
Speaker 2: So the inertia alone means an engine that massive physically
Speaker 2: cannot stop that fast. You can't hit the brakes on
Speaker 2: something light years wide and expect it to halt in
Speaker 2: twenty years.
Speaker 3: And that right there is the twenty year glitch. Yeah,
Speaker 3: that is exactly where standard physics breaks down in this case.
Speaker 2: Okay, so let's dig into that glitch. What is the
Speaker 2: normal behavior supposed to.
Speaker 3: Be to understand the anomaly? We have to establish that
Speaker 3: baseline of normal behavior. Active glactic nuclei do vary in brightness,
Speaker 3: that is known, right.
Speaker 2: They aren't perfectly steady.
Speaker 3: Because the flow of gas into the disc is turbulent
Speaker 3: and clumpy. It's not a perfectly smooth stream. Because of this,
Speaker 3: it is completely standard for an agn to vary in
Speaker 3: its luminous output by about thirty percent over months or
Speaker 3: even years.
Speaker 2: Okay, so a thirty percent variation that makes sense to me.
Speaker 2: That's like a flickering light bulb on your front porch.
Speaker 3: Right.
Speaker 2: Sometimes the current waivers a bit, the filament cools for
Speaker 2: a microsecond, and it dims, then it brightens again.
Speaker 3: A perfect analogy. That's just the normal breathing.
Speaker 2: Of the accretion disc, but dropping to five percent of
Speaker 2: its original brightness, dropping by a factor of twenty.
Speaker 3: Yeah, that's different.
Speaker 2: That is not a flicker. That's someone walking over and
Speaker 2: violently ripping the power cable right out of the wall.
Speaker 3: Exactly. And when astrophysicists build models to describe the physics
Speaker 3: of these accretion discs, they deal with very specific mathematical time.
Speaker 2: Scales, well kind of timescales.
Speaker 3: Well, there is the dynamical time scale, which dictates how
Speaker 3: fast things orbit the black hole. Okay, but more importantly
Speaker 3: for this mystery, there is the viscous timescale.
Speaker 2: This is like viscosity, like honey.
Speaker 3: Exactly, it's the time it takes for mass to actually
Speaker 3: flow through the friction of the disk and eventually fall
Speaker 3: into the black hole.
Speaker 2: Ah, I see.
Speaker 3: And for a supermassive black hole, the viscous timescale is
Speaker 3: immense changes in the fundamental mass secretion rate. The actual
Speaker 3: fueling of the black hole should happen incredibly slowly, slowly
Speaker 3: over tens of thousands of years at the absolute.
Speaker 2: Mid So, meaning if you hypothetically cut off the fuel
Speaker 2: supply at the outer edge of the disc today. Yes,
Speaker 2: it should still take tens of thousands of years for
Speaker 2: the inner part of the disk to finally drain out
Speaker 2: and go dark.
Speaker 3: Yes, the math simply does not allow an object containing
Speaker 3: hundreds of millions of solar masses to shut down its
Speaker 3: primary energy generation in twenty years.
Speaker 2: It's just too fast.
Speaker 3: Way too fast. To put it in geological terms, down
Speaker 3: here on Earth, it is equivalent to watching the entire
Speaker 3: Himalayan mountain range completely level out into a flat plane overnight. Wow,
Speaker 3: just wake up and the mountains are gone.
Speaker 2: And if a geologist saw the Himalays flatten overnight, their
Speaker 2: first instinct would be to assume their equipment was broken.
Speaker 3: Exactly. You check your sensors, right.
Speaker 2: You can't just claim you broke standard physics without bringing absolute,
Speaker 2: ironclad receipts.
Speaker 3: And these researchers knew that.
Speaker 2: So to prove this wasn't just some instrument error, astronomers
Speaker 2: had to pull together an unprecedented multi generational investigation, and.
Speaker 3: The methodology they used is just a masterclass in ovational astronomy.
Speaker 2: Let's walk through that detective work, because it's fascinating.
Speaker 3: It really is. The discovery wasn't a sudden eureka moment
Speaker 3: at a telescope by piece where someone.
Speaker 2: Gasped, you know, right, It's not like in the movies.
Speaker 3: No, It relied on comparing immense digital data sets that
Speaker 3: were separated by nearly two decades and then corroborating all
Speaker 3: of that with historical archives.
Speaker 2: Okay, so where does the timeline start.
Speaker 3: The before picture? The baseline of this roaring bright agn
Speaker 3: was established around two thousand and two by the Sloan
Speaker 3: Digital Sky Survey.
Speaker 2: Okay, the SDSS, that's pretty legendary and astronomy circles right.
Speaker 3: Oh, absolutely. It wasn't just looking at individual objects. It
Speaker 3: essentially created one of the first highly detailed, massive three
Speaker 3: D maps of the observable universe.
Speaker 2: Scanning massive swaths of the sky night after night.
Speaker 3: Exactly, and it provided a vital benchmark for what the
Speaker 3: sky looked like at the turn of the millennium.
Speaker 2: Right, But obviously, astronomy technology evolves incredibly rapidly.
Speaker 3: It does. Fast forward to twenty eighteen and re searchers
Speaker 3: were using the hypersuprimecam the HC right mounted on the
Speaker 3: super Bru telescope in Hawaii. The HSC uses these highly
Speaker 3: advanced charge coupled devices that are far, far more sensitive
Speaker 3: than what was available back in two thousand and two.
Speaker 2: So they get a much crisper look.
Speaker 3: Exactly. So this international collaboration, which by the way, required
Speaker 3: coordinating massive teams across Japan, Germany and Spain just to
Speaker 3: process the sheer volume of data.
Speaker 2: Just moving the hard drives must have been a nightmare.
Speaker 3: Seriously. But when they compared the twenty eighteen HSC images
Speaker 3: to the two thousand and two SDSS data, the discrepancy
Speaker 3: in Jay zero two eighteen was glaring.
Speaker 2: The light had simply vanished.
Speaker 3: It is just gone.
Speaker 2: But seeing a discrepancy between two digital surveys is you know,
Speaker 2: it's a great start, but it's not enough to rewrite
Speaker 2: the text.
Speaker 3: Posts and nave and close. You need confirmation, right.
Speaker 2: So they launched this massive follow up campaign.
Speaker 3: They threw everything they had at it.
Speaker 2: They brought in the Grand Telescopeio Canarias. They brought in
Speaker 2: the WMCC Observatory for new optical and near infrared observations. Yeah,
Speaker 2: they pulled in X ray data, they pulled in radio
Speaker 2: wave data.
Speaker 3: All across the spectrum.
Speaker 2: And then my absolute favorite part, They went into the
Speaker 2: physical vaults. Yes, the archival sleuthing scientists literally pulled out
Speaker 2: physical photographic plates taken roughly seventy years ago to build
Speaker 2: a complete historical timeline of this galaxy.
Speaker 3: It really is a stunning validation of the importance of
Speaker 3: preserving archival data.
Speaker 2: I mean seventy years ago. We are talking about chemical.
Speaker 3: Emulsions, long before digital sensors ever existed. But those old
Speaker 3: plates allowed the team to confirm that this sudden dimming
Speaker 3: wasn't just a return to some historical norm ah Okay,
Speaker 3: it allowed them to track the long term behavior of
Speaker 3: the agn over decades and definitively confirmed that the twenty
Speaker 3: year drop was a genuine, unprecedented anomaly in the object's history.
Speaker 2: Okay, hold on, I have to push back on the
Speaker 2: methodology here for a second. Sure, I love the idea
Speaker 2: of modern astronomers dusting off seventy year old physical place,
Speaker 2: but you're telling me a piece of glass coded in
Speaker 2: chemicals from the nineteen fifties is being used to verify
Speaker 2: a ten billion year old cosmic anomaly.
Speaker 3: That is exactly what I'm telling you.
Speaker 2: But how do we know the emulsion on those plates
Speaker 2: hasn't just degraded over the decades. How can we trust
Speaker 2: an old piece of glass sitting in a drawer to
Speaker 2: rewrite modern astrophysics.
Speaker 3: It is a very valid skepticism, and it's something astronomers
Speaker 3: actively account for through rigorous calibration.
Speaker 2: Okay, how do they calibrate a seventy year old photo.
Speaker 3: Well, you don't just look at the single galaxy on
Speaker 3: the glass plate in isolation. You look at the entire
Speaker 3: field of view captured on that piece of glass. Okay,
Speaker 3: you measure the brightness of Jay zero two eighteen against
Speaker 3: the brightness of dozens of steady, non variable stars they
Speaker 3: were captured on that exact same photographic plate.
Speaker 2: Oh I see right.
Speaker 3: So if the chemical emulsion simply degraded over time, the
Speaker 3: reference stars would also look dimmer to us.
Speaker 2: Now, that is brilliant.
Speaker 3: By measuring the relative brightness between the galaxy and those
Speaker 3: steady stars, the chemical degradation of the physical plate is
Speaker 3: completely factored out of the equation.
Speaker 2: Okay, that makes perfect sense. The steady stars act as
Speaker 2: an internal control group for the plate's physical condition.
Speaker 3: Exactly. It's very clever, it is.
Speaker 2: But let's look at the modern follow up data they
Speaker 2: gather because I have another question there. Shoot, why did
Speaker 2: they need radio X ray and optical data? I mean,
Speaker 2: if the light went out, shouldn't a regular standard visible
Speaker 2: light telescope be enough to tell us that? Why throw
Speaker 2: the entire electromagnetic spectrum of the problem.
Speaker 3: Because different wavelengths of light review entirely different physical mechanisms
Speaker 3: within the ag in itself. Okay, explain that if you
Speaker 3: only look at visible light the optical stuff, you miss
Speaker 3: the vast majority of the actual physics going on. Yeah,
Speaker 3: An active glyphic nucleus is a complex layered ecosystem.
Speaker 2: It's not just one glowing ball.
Speaker 3: No, it is governed by extreme thermal gradients. So the
Speaker 3: inner region right next to the black hole is the hottest.
Speaker 2: Part, right where the friction is crazy exactly.
Speaker 3: Because it's so hot, it produces high energy short wavelength
Speaker 3: X ray.
Speaker 2: So it's kind of like the blue flame on a
Speaker 2: blowtorch being hotter than the yellow flame on a candle.
Speaker 3: That is a fantastic parallel. Yes, Okay, Then the swirling
Speaker 3: gas further out from the center is slightly cooler, relatively speaking,
Speaker 3: so that produces your optical and ultraviolet light.
Speaker 2: So that's the yellow flame, right.
Speaker 3: And then even further away from the black hole, you
Speaker 3: have this massive torus, essentially a giant donut shape of
Speaker 3: cosmic dust, a dust donut, a dust donut, and that
Speaker 3: dust actually absorbs the inner light and reradiates it as
Speaker 3: long wavelength infrared heat.
Speaker 2: Oh wow, So you have X rays in the middle,
Speaker 2: optical in the middle ring, and infrared on the outer edge.
Speaker 3: Phcisely. So by looking at all these different wavelengths, researchers
Speaker 3: aren't just checking to see if the object as a
Speaker 3: whole got darker.
Speaker 2: They are diagnosing which specific parts of the engine.
Speaker 3: Broke down exactly. They're checking the spark plugs, the fuel line, everything.
Speaker 2: And more importantly, using those different wavelengths was the only
Speaker 2: way to rule out the absolute most common suspect and astronomical.
Speaker 3: Mysteries, which is cosmic dust.
Speaker 2: Exactly because whenever something gets unexpectedly dim in space, it
Speaker 2: feels like the first instinct is always did a giant
Speaker 2: cloud of dust just float in front of it?
Speaker 3: It is the most logical assumption based on Okham's razor.
Speaker 3: I mean, space is incredibly dusty, right, Galaxies are filled
Speaker 3: with these immense, sweeping clouds of silicates and carbonaceous grains
Speaker 3: that were forged in the depths of older stars.
Speaker 2: It's very crowded, very so.
Speaker 3: The most obvious answer to the question why did the
Speaker 3: light suddenly get dark is simply something got in the.
Speaker 2: Way, the hypothesis being that a dense cloud of interstellar
Speaker 2: dust basically just drifted across our line of sight.
Speaker 3: Right interposing itself between our telescopes on Earth and the
Speaker 3: accretion disc ten billion light years away.
Speaker 2: And if that happened, it's not like the projector broke.
Speaker 2: It's like someone just walked in front of the projector,
Speaker 2: blocking the movie.
Speaker 3: Yes, the engine itself would still be chugging along perfectly fine.
Speaker 3: It would just be hidden behind a curtain of dust.
Speaker 2: But they proved it wasn't dust.
Speaker 3: They absolutely did. So.
Speaker 2: How does looking at different wavelengths dismantle the dust cloud theory?
Speaker 3: It comes down to the physics of scattering. Scattering, specifically,
Speaker 3: how the physical size of a light wavelength interacts with
Speaker 3: the physical size of a dust particle.
Speaker 2: Okay, break that down for me.
Speaker 3: Cosmic dust particles are incredibly tiny, and visible optical light
Speaker 3: has very short wavelengths. When those short, tightly packed wavelengths
Speaker 3: hidden the tiny dust particles. They scatter like hitting a
Speaker 3: wall exactly. The light bounces off in different directions and
Speaker 3: it never reaches their telescopes. That's why dust blocks visible
Speaker 3: light so well.
Speaker 2: But infrared light behaves.
Speaker 3: Differently, completely differently. Infrared light has a much much longer wavelength. Okay,
Speaker 3: because the waves are physically longer than the dust particles themselves,
Speaker 3: they don't scatter efficiently. The infrared light essentially bypasses the
Speaker 3: dust entirely.
Speaker 2: It just pierces straight through, yes, right.
Speaker 3: Through dense clouds that would completely block visible light.
Speaker 2: Let's try to ground this with an analogy, because I
Speaker 2: want to make sure I'm visualizing this right.
Speaker 3: Go for it.
Speaker 2: It's like standing on a pier looking at the ocean. Okay,
Speaker 2: the massive long ocean swells, those would represent the infrared waves.
Speaker 2: They roll right past the wooden pilings of the pier
Speaker 2: like they aren't even there. Yes, But the tiny choppy
Speaker 2: ripples on the surface representing the short optical wavelengths, those
Speaker 2: smash into the wood and scatter in all directions.
Speaker 3: That perfectly captures the physics of wavelength depended scattering.
Speaker 2: I love that, Okay, So applying that to the galaxy.
Speaker 3: Right, If a dust cloud had just drifted in front
Speaker 3: of JO two one eight, the short wavelength visible light
Speaker 3: would have crashed into the dust and scattered.
Speaker 2: Which would cause a massive drop in the optical brightness
Speaker 2: we see on Earth exactly.
Speaker 3: But the long wavelength infrared light, which is pouring out
Speaker 3: of that hot, dusty torus surrounding the agn that should
Speaker 3: have rolled right past the obstruction.
Speaker 2: So the infrared should have remained relilatively steady in our observations.
Speaker 3: It should have if it was just dust.
Speaker 2: But when the researchers actually analyzed the data across the spectrum,
Speaker 2: they found that both the optical light and the infrared
Speaker 2: light dropped dramatically at the exact same time.
Speaker 3: And that synchronized drop completely destroys the dust cloud hypothesis.
Speaker 2: Because dust can't block.
Speaker 3: Infrared exactly, a physical dust obstruction cannot hide the infrared
Speaker 3: signature of an active accretion disk. Because the infrared light
Speaker 3: vanished alongside the optical light, the scientists were backed into
Speaker 3: a corner.
Speaker 2: They were left with only one terrifyingly fast conclusion regarding
Speaker 2: the physical state of the galaxy.
Speaker 3: Right, the engine didn't get covered up.
Speaker 2: The engine starved.
Speaker 3: Yes, the fuel shut down, we shift from a mystery
Speaker 3: of missing light to a fundamental breakdown of cosmic mechanics.
Speaker 2: So what did the data tell them about the fuel supply?
Speaker 3: By feeding these simultaneous multi wavelength drops into complex theoretical models,
Speaker 3: the researchers determined that the mass s acrete rate, the
Speaker 3: actual physical flow of plasma falling into the black hole plummeted.
Speaker 3: How far down it dropped to about one fiftieth of
Speaker 3: its previous level.
Speaker 2: One fiftieth Yeah, so it essentially dropped to two percent
Speaker 2: of its original fuel intake, its fusmiums. And the most
Speaker 2: shocking part here has to be the timeline. This starvation
Speaker 2: didn't take tens of thousands of years, like that viscous
Speaker 2: timescale math suggests it should.
Speaker 3: No, it didn't.
Speaker 2: It happened in a mere seven years.
Speaker 3: Seven years, which is an infinitesimally small fraction of time
Speaker 3: in astrophysics, right.
Speaker 2: I mean seven years. That's less time than it takes
Speaker 2: to get a medical degree, it really is. And to
Speaker 2: go from a roaring galaxy illuminating cosmic furnace to sheer
Speaker 2: starvation mode in just seven years.
Speaker 3: It indicates a catastrophic instantaneous phase change in the accretion
Speaker 3: disks physical structure.
Speaker 2: But if the fuel supply just vanished, where did all
Speaker 2: that mass go? I mean, we're talking about a vortex
Speaker 2: of superheated plasma, likely millions of times more massive than
Speaker 2: the Earth Earth. It can't just disappear.
Speaker 3: And that is the lingering million dollar question keeping theoretical
Speaker 3: physicists awake at night. I bet, because we know an
Speaker 3: accretion disc is maintained by a delicate balance of extreme forces.
Speaker 2: What forces, well, the I mense.
Speaker 3: Gravity of the supermassive black hole is constantly trying to
Speaker 3: crush all that gas inward, right But the incredible heat
Speaker 3: generated by the friction creates intense radiation pressure, and that
Speaker 3: radiation pressure is pushing outward. So the disk exists in
Speaker 3: this fragile balance between gravity pulling in and light pushing out.
Speaker 3: It's a concept closely related to the Eddington limit.
Speaker 2: Okay, So if the fuel supply drops to one fiftieth,
Speaker 2: that delicate balance collapses instantly. The outward radiation pressure basically.
Speaker 3: Dies exactly and exactly what happens next is heavily debated
Speaker 3: in the field.
Speaker 2: Right now, what are the main theories.
Speaker 3: One major theory is that the disc might transition into
Speaker 3: what physicists call a radiatively inefficient accretion flow or.
Speaker 2: A riaf riaf.
Speaker 3: Yeah. In this state, the plasma basically becomes so diffuse
Speaker 3: that it can no longer cool itself efficiently by emitting light.
Speaker 2: Okay, so it stops glowing, right.
Speaker 3: The energy gets trapped as thermal heat, and the disc
Speaker 3: puffs up into a faint, practically invisible sphere of gas
Speaker 3: rather than a brilliant, glowing whirlpool.
Speaker 2: But what triggers that drop in the fuel in the
Speaker 2: first place? How do you lose the flow so quickly?
Speaker 3: That's the real mystery, because it can't be.
Speaker 2: Like pulling a plug in a bathtub that I employs
Speaker 2: gravity just smoothly drains the water. But we are talking
Speaker 2: about plasma moving at relativistic speeds, right.
Speaker 3: A better way to visualize it is imagine a massive
Speaker 3: high speed highway where suddenly the structural integrity of the
Speaker 3: bridge just completely fails.
Speaker 2: It trumbles.
Speaker 3: Yeah. The plasma is being held in its orbit by
Speaker 3: magnetic fields and angular momentum. So one theory is a
Speaker 3: massive magnetic anomaly, likewise like a sudden inversion or snapping
Speaker 3: of the magnetic field lines. This could instantly strip the
Speaker 3: inner regions of the disk of all their angular.
Speaker 2: Momentum, and without angular momentum keeping it in orbit, essentially
Speaker 2: spinning around, the plasma has nothing fighting gravity anymore.
Speaker 3: The structural support vanishes, and a massive chunk of the
Speaker 3: inner disc simply plunges into the event horizon almost instantaneously. Wow,
Speaker 3: leaving an empty, starved cavity behind.
Speaker 2: That is terrifying.
Speaker 3: It gets wilder. Another theory suggests the exact opposite extreme,
Speaker 3: which is that the energy generated by the accretion process
Speaker 3: briefly surged, creating these powerful magnetically driven.
Speaker 2: Winds winds in space.
Speaker 3: Cosmic winds, And these winds were so intense they literally
Speaker 3: blew the inner region of the disc apart.
Speaker 2: Just blasted it away.
Speaker 3: Exactly sweeping the gas outward and completely severing the fuel
Speaker 3: line to the black hole.
Speaker 2: I mean, both of those scenarios sound incredibly violent.
Speaker 3: They are exceedingly violent. But the truth is, the specific
Speaker 3: mechanism capable of causing a gas supply of this magnitude
Speaker 3: to shut off in seven years remains a theoretical ghost.
Speaker 2: We just don't know.
Speaker 3: We have observed the undeniable aftermath. The lights are off,
Speaker 3: but the physical catalyst is still hiding in the dark.
Speaker 2: And the fact that our current standard models cannot explain
Speaker 2: how a supermassive black hole goes on a sudden starvation
Speaker 2: diet in seven years. It's forcing a complete rethink of
Speaker 2: cosmic evolution, isn't it.
Speaker 3: Oh? Absolutely, this discovery isn't just a quirky footnote in
Speaker 3: some journal. It is actively rewriting the future of astrophysics.
Speaker 2: Because it upends that universally accepted view of slow gradual
Speaker 2: agn evolution completely.
Speaker 3: One of the co authors of the study, Toshihiro Kawaguchi,
Speaker 3: pointed out that this rapid variability simply cannot be explained
Speaker 3: by standard models.
Speaker 2: Our mathematics literally do not account for a massive accretion
Speaker 2: disc graining in under a decade.
Speaker 3: No, the math says, it's impossible.
Speaker 2: I imagine that for a theoretical physicist, though, having your
Speaker 2: standard model's break is actually a really thrilling moment.
Speaker 3: Oh, it's the best day of your life. Right.
Speaker 2: It means there's an entirely new layer of physics waiting
Speaker 2: to be discovered.
Speaker 3: Science advances when we find the anomaly. When we find
Speaker 3: the thing that shouldn't exist but undeniably.
Speaker 2: Does, and Jay zero two one teen is that anomaly exactly.
Speaker 3: It now serves as a vital test case. Theoretical physicists
Speaker 3: have a new goalpost.
Speaker 2: What's the goalpost?
Speaker 3: They must design a mathematical model of an accretion disk
Speaker 3: that actually allows for a catastrophic structural failure in seven
Speaker 3: years without violating the fundamental laws of thermodynamics.
Speaker 2: Which is going to be incredibly difficult.
Speaker 3: It's a huge challenge.
Speaker 2: It's like geology, assuming all mountains erode slowly over millions
Speaker 2: of years, right right, and then setting up a camera
Speaker 2: and watching one specific mountain just completely flatten out on
Speaker 2: a Tuesday afternoon. Yes, we don't just quit science and
Speaker 2: throw our hands up. We realize we need completely new
Speaker 2: physics to explain the Tuesday Mountain.
Speaker 3: I love that the Tuesday Mountain and the search for
Speaker 3: more of these Tuesday mountains is already defining the next
Speaker 3: era of observational.
Speaker 2: Astronomy because we have to find out if this is
Speaker 2: a one off, freak accident or pattern exactly.
Speaker 3: Tomoki Morrikuma, who led the study, he really emphasized the
Speaker 3: critical shift happening right now with wide field.
Speaker 2: Surveys right, the way we look at the sky is changing.
Speaker 3: It is for centuries. Astronomy was basically about pointing a
Speaker 3: telescope at one specific, tiny key hole in the sky
Speaker 3: and studying.
Speaker 2: It deeply, right, looking at one star or one galaxy
Speaker 2: for hours.
Speaker 3: But the problem is you remain completely blind to the
Speaker 3: ninety nine point nine percent of the sky you aren't
Speaker 3: looking at.
Speaker 2: But with new tools like the hypersuprime cam and all
Speaker 2: these upcoming facilities that are designed to map the entire
Speaker 2: sky every few nights, we.
Speaker 3: Are shifting from taking static polaroids to basically recording a
Speaker 3: continuous dynamic movie of.
Speaker 2: The universe, which is incredible.
Speaker 3: That wide field capability is literally the only reason we
Speaker 3: caught this seven year shut down in j zero two eighteen.
Speaker 2: Because if you only look at a galaxy once a century,
Speaker 2: you will miss these rapid, fleeting phase changes entirely.
Speaker 3: You never even know they happen.
Speaker 2: Which raises a massive question on what if Jay zero
Speaker 2: two on you isn't a freak accident. What if as
Speaker 2: these wide field surveys continuously monitor the sky over the
Speaker 2: next few years, we start finding dozens or hundreds of
Speaker 2: these rapidly starving supermassive black holes.
Speaker 3: If this rapid shutdown is found to be a common occurrence,
Speaker 3: it fundamentally ulsters our understanding of galaxy evolution as a.
Speaker 2: Whole, because it would suggest that supermassive black holes don't
Speaker 2: just slowly steadily burn through their fuel over eons, right.
Speaker 3: It would mean they gorge themselves abruptly and violently shut
Speaker 3: down and then perhaps restart again in these cyclical cosmic hiccups.
Speaker 2: And because the black hole is the engine right at
Speaker 2: the center of the galaxy, its behavior dictates the environment
Speaker 2: of the entire galaxy around.
Speaker 3: It, exactly. It's connected to everything. The extreme radiation from
Speaker 3: an active agn heats up the gas in the surrounding galaxy.
Speaker 2: And hot gas can't form stars, right.
Speaker 3: It actually prevents new stars from forming. It essentially sterilizes
Speaker 3: the galaxy. Okay, But if a black hole can suddenly
Speaker 3: shut up its energy output in just seven years, it
Speaker 3: drastically immediately changes the thermal environment of the host galaxy.
Speaker 2: The gas cools down, yes.
Speaker 3: And that can potentially trigger sudden massive bursts of new
Speaker 3: star formation. So the life cycle of the central black
Speaker 3: hole is intimately tied to the life cycle of every
Speaker 3: single star system around it.
Speaker 2: It's all connected. It really paints a picture of a
Speaker 2: universe that is breathing, flickering, surging, and starving all the
Speaker 2: time right over our heads.
Speaker 3: It's far more alive than we give it credit for.
Speaker 2: Think about your own perception of the night sky for
Speaker 2: a second. We use the stars as these ultimate symbols
Speaker 2: of eternity and permanence. We do We just assume the
Speaker 2: cosmos is this quiet, ancient backdrop to our super fast
Speaker 2: paced human lives. But the evidence from Jay zero two
Speaker 2: eight clearly shows that the universe is just as restless, unpredictable,
Speaker 2: and capable of sudden shocking transformations as absolutely anything here
Speaker 2: on Earth.
Speaker 3: It is a highly active, turbulent landscape, and are really
Speaker 3: only just now building the observational infrastructure capable of watching
Speaker 3: that turbulence unfold in real time.
Speaker 2: We're finally opening our eyes.
Speaker 3: Every new anomaly we find forces us to look deeper
Speaker 3: and refine our understanding of the extreme physics governing the dark.
Speaker 2: Which leaves us with a truly mind bending final thought
Speaker 2: for you to ponder tonight.
Speaker 3: Let's hear it.
Speaker 2: The light from the starving black hole took ten billion
Speaker 2: years to cross the void and reach your telescopes, delivering
Speaker 2: a message of sudden, catastrophic change that happened long before
Speaker 2: our planet even existed, long before. So when you look
Speaker 2: up at that seemingly quiet sky tonight, ask yourself this,
Speaker 2: What other invisible cosmic alarms are going off right now?
Speaker 3: That's a chilling thought.
Speaker 2: What massive instantaneous transformations in the very fabric of the
Speaker 2: universe are rushing toward Earth at the speed of light
Speaker 2: right now, carrying the news of a radically altered cosmos.
Speaker 3: News that our descendants won't actually see for another billion years. Exactly,
Speaker 3: the universe is constantly broadcasting its evolution. Just have to
Speaker 3: keep our instruments calibrated, our minds open, and well be
Speaker 3: willing to throw away the rule book when the light
Speaker 3: finally arrives s