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 start by picturing something for me.
Speaker 2: You step outside on a clear, crisp, moonless night, Oh.
Speaker 3: The best kind of night for stargazing.
Speaker 2: Exactly. You look up and you see that familiar breath
Speaker 2: taking expanse. You know, the sparkling, distinct points of light,
Speaker 2: the deep ink black voids between them, maybe.
Speaker 3: Even the faint, sort of misty smudge of our own
Speaker 3: milky way stretching across the horizon if you're lucky.
Speaker 2: Right, Exactly, it's crisp, it's defined. You were looking through
Speaker 2: this incredibly transparent window of our universe.
Speaker 3: Yeah, and you can see things that are literally million
Speaker 3: of light years away, simply because the space between you
Speaker 3: and that object is empty.
Speaker 2: It's empty. But now I want you to take that image,
Speaker 2: that fundamental human experience of stargazing and just completely erase it.
Speaker 2: E RaSE the whole sky, the whole thing. Yeah, I
Speaker 2: want you to replace that pristine, starry canvas with something
Speaker 2: entirely different. Imagine looking up and instead of stars, you
Speaker 2: see nothing but a thick, impenetrable, murky gray fog.
Speaker 3: Wow, just fog everywhere.
Speaker 2: Yeah, no points of light, no definition at all, just
Speaker 2: this oppressive cosmic soup blocking your view in every single direction.
Speaker 3: That is. I mean, that's a really unsettling image.
Speaker 2: It really is. And the crazy thing is, for roughly
Speaker 2: the first billion years of its existence, that is exactly
Speaker 2: what our universe looked like. It was completely hidden behind
Speaker 2: this veil.
Speaker 3: It defies every intuition we have about the cosmos, honestly,
Speaker 3: because when we think of space, we inherently think of
Speaker 3: empty space.
Speaker 2: Right, just a big empty vacuum, exactly.
Speaker 3: We think of a perfect vacuum that light can just
Speaker 3: travel through uninterrupted for billions of years. But that fundamental transparency,
Speaker 3: it's actually a feature that had to be.
Speaker 2: Earned, earned. What do you mean by earned, Well, it.
Speaker 3: Had to be forged. The early universe was not an
Speaker 3: empty vacuum at all. It was choked with this primordial
Speaker 3: fog that fundamentally trapped energetic light.
Speaker 2: So we are going to take you back today, roughly
Speaker 2: twelve billion years in time, to witness this pivotal, almost
Speaker 2: unbelievable moment in cosmic.
Speaker 3: History, really specific moment.
Speaker 2: Yeah, we are going back to watch this tiny, hyperactive,
Speaker 2: absolute underdog of a galaxy managed to punch a physical
Speaker 2: hole right through that universal darkness.
Speaker 3: It's quite the story.
Speaker 2: Our goal today is to understand how astronomers have managed
Speaker 2: to capture the precise mechanics of this ancient event, an
Speaker 2: event that literally changed the fabric of the universe.
Speaker 3: The sheer scale of the mystery we are talking about
Speaker 3: here is just staggering because understanding this moment and this
Speaker 3: specific galaxy. It isn't just about cataloging incredibly distant ancient
Speaker 3: star system for the sake of making a list.
Speaker 2: Right, It's not just stamp collecting exactly.
Speaker 3: We are talking about solving a decade's old mystery in astrophysics.
Speaker 3: We're talking about answering the fundamental question of how the
Speaker 3: universe transitioned from that dark, opaque expanse into the transparent,
Speaker 3: light filled cosmos we have today.
Speaker 2: The cosmos that allows us to even exist and look
Speaker 2: up at the sky exactly.
Speaker 3: It's literally the story of how the lights were permanently
Speaker 3: turned on.
Speaker 2: Okay, so to really grasp the magnitude of this, we
Speaker 2: need to completely understand the environment we are dealing with. Here.
Speaker 2: We are talking about a specific era.
Speaker 3: Astronomers call it the era of reionization.
Speaker 2: Right, the era of realization. So let's establish the timeline
Speaker 2: for everyone. The Big Bang happens. The universe is unbelievably hot.
Speaker 3: And dense, and as it expands, it starts to cool down.
Speaker 2: And for roughly the first billion years after that initial spark,
Speaker 2: the space between the newly forming stars and galaxies wasn't empty.
Speaker 3: Yeah, not at all.
Speaker 2: Was completely filled with neutral hydrogen gas, and this gas
Speaker 2: acted as a literal physical barrier, like an opaque wall
Speaker 2: to energetic ultraviolet light.
Speaker 3: And the physics of why this specific gas acts as
Speaker 3: a wall is actually really critical.
Speaker 2: Here, walk us through that. Why hydrogen, Well.
Speaker 3: When the universe was born, it was essentially this giant
Speaker 3: expanding furnace. It was a plasma where protons and electrons
Speaker 3: were just violently zipping around because it was so hot,
Speaker 3: way too energetic to bond together. Yeah, but as the
Speaker 3: universe expanded, the temperature naturally dropped, makes sense, and about
Speaker 3: three hundred and eighty thousand years after the Big Bang,
Speaker 3: it cooled just enough for those protons and electrons to
Speaker 3: finally grab onto each other, and that's.
Speaker 2: When they form the very first atoms.
Speaker 3: Exactly specifically, they formed neutral hydrogen, which is just one
Speaker 3: proton and one electron locked together in this little atomic dance.
Speaker 2: Now on the surface, that seems like a good thing, right,
Speaker 2: like a step toward order. The universe is organized itself
Speaker 2: into atoms.
Speaker 3: It was a huge step for matter, but for light
Speaker 3: it was a disaster, right.
Speaker 2: Because in terms of light, this new order created a
Speaker 2: massive problem. I always think of this era like a
Speaker 2: frosted glass window in a bathroom.
Speaker 3: Oh, that's a good way to look at it.
Speaker 2: Yeah, you know, you can stand on the outside of
Speaker 2: that window, and you know there's a bright light source
Speaker 2: on the inside. You know, someone turned a light bulb.
Speaker 3: On, but you can't see the ball itself exactly.
Speaker 2: The material of that frosted glass scatters every single photon
Speaker 2: that hits it. You can't see the shape of the ball,
Speaker 2: you can't see the room. Everything is just scattered into
Speaker 2: this hazy, indistinguishable glow.
Speaker 3: That's exactly it. That neutral hydrogen was the frosted glass
Speaker 3: of the universe, and it was specifically tuned to block
Speaker 3: the high energy ultraviolet light being produced by the very first.
Speaker 2: Stars, tuned to block it. How does that work?
Speaker 3: Your frosted glass analogy works perfectly. When you look at
Speaker 3: the quantum mechanics of a hydrogen atom, you see neutral
Speaker 3: hydrogen atoms are essentially perfect tuned traps for energetic ultraviolet.
Speaker 2: Photons, like they're designed to catch them.
Speaker 3: Pretty much. In a neutral atom, the electron is sitting
Speaker 3: at its lowest energy state. So when an energetic ultraviolet
Speaker 3: photon from a newly born star comes along and hits
Speaker 3: that neutral hydrogen.
Speaker 2: Atom, the atom just absorbs it.
Speaker 3: Yep, the atom's electron absorbs that energy and physically jumps
Speaker 3: away from the proton into a higher orbit. The light
Speaker 3: doesn't pass through at all, it's just consumed.
Speaker 2: Wow.
Speaker 3: Its energy is used to excite or even break the
Speaker 3: atom apart. So any young hot star trying to shine
Speaker 3: its brilliant UV light out into the cosmos would just
Speaker 3: find its light immediately swallowed by the surrounding hydrogen fog.
Speaker 2: Okay, this is where I want to push back a
Speaker 2: little bit, because I think if you were listening to this,
Speaker 2: a very logical counter argument might be forming in your head.
Speaker 3: Oh, let's hear it.
Speaker 2: Well, we know the universe was expanding, right, It has
Speaker 2: been expanding since the moment of the Big Bang, and
Speaker 2: the actual fabric of space is still stretching today.
Speaker 3: That's true.
Speaker 2: So if this fog is just made of gas and
Speaker 2: the literal space it occupies is stretching out and getting bigger,
Speaker 2: shouldn't that neutral hydrogen fog have just naturally stretched out,
Speaker 2: thinned out, and dissipated on its.
Speaker 3: Own over time, like a cloud of smoke blowing away.
Speaker 2: Exactly why campfire smoke dispersing in the wind? Why do
Speaker 2: astronomers believe something had to actively violently clear it.
Speaker 3: That is a really great question. In connecting it to
Speaker 3: cosmic expansion makes complete sense, but it actually highlights the
Speaker 3: slight misunderstanding of what expansion does to matter at this
Speaker 3: specific scale.
Speaker 2: Okay, correct me, what am I missing?
Speaker 3: Yes, the universe was expanding, which means the average distance
Speaker 3: between galaxies was increasing, So the overall density of the
Speaker 3: gas in the universe was very slowly decreasing.
Speaker 2: Right, It's spreading out.
Speaker 3: But and this is the key, physical expansion alone does
Speaker 3: not change the chemical or electrical state of the gas itself.
Speaker 2: Oh I see, So just spreading the atoms further apart
Speaker 2: doesn't stop them from being a trap for the light exactly.
Speaker 3: Let's follow that logic. Even if the hydrogen atoms are
Speaker 3: slightly further apart from one another due to the stretching
Speaker 3: of space, they are still fundamentally neutral hydrogen.
Speaker 2: They still have that electron waiting to catch a photon bingo.
Speaker 3: They still possess that perfectly positioned electron. So if a
Speaker 3: photon travels through space, eventually it will hit one of
Speaker 3: these atoms, no matter how spread out they.
Speaker 2: Are, because there's just so much space to cross.
Speaker 3: Right, to make the universe truly transparent, to give us
Speaker 3: the clear night sky, you couldn't just thin the fog out.
Speaker 3: You had to fundamentally alter the nature of the fog itself.
Speaker 2: You had to change the gas.
Speaker 3: Yes, you had to change it from a neutral state
Speaker 3: back into an ionized.
Speaker 2: Plasma, Which means we need to define ionization for everyone,
Speaker 2: because to ionize a gas, you essentially have to break
Speaker 2: the atom.
Speaker 3: Right, It is a totally destructive process. Yeah, ionization is
Speaker 3: the act of literally ripping the electron away from the proton.
Speaker 2: Entirely, so you're not just exciting the electron, you're kicking
Speaker 2: it out exactly.
Speaker 3: Have to hit that neutral hydrogen atom with an overwhelming
Speaker 3: amount of energetic ultraviolet light, so much energy that the
Speaker 3: electron is violently and permanently stripped away.
Speaker 2: And once that happens.
Speaker 3: When that happens, the gas becomes ionized, and ionized hydrogen,
Speaker 3: missing its electron, no longer has the mechanism to absorb
Speaker 3: that same ultraviolet.
Speaker 2: Light because the trap is gone.
Speaker 3: The trap is gone, the photon can finally pass right
Speaker 3: through the empty space of the atom unimpeded. To use
Speaker 3: your analogy, the frosted glass suddenly becomes a pane of
Speaker 3: clear glass.
Speaker 2: That is wild. So to clear the cosmic fog, the
Speaker 2: universe literally had to be blasted with radiation on an
Speaker 2: unimaginable scale.
Speaker 3: It really did. And this change over this era of realization,
Speaker 3: it was not a quick.
Speaker 2: Transition, wasn't just slipping a switch, not at all.
Speaker 3: It was an incredibly grueling, violent process. It was a
Speaker 3: cosmic war of attrition that took hundreds of millions of
Speaker 3: years to complete.
Speaker 2: Hundreds of millions of years of just bombarding.
Speaker 3: Gas photon by photon. The earliest stars were fighting back
Speaker 3: against the fog doug stripping electrons away and gradually carving
Speaker 3: out these tiny bubbles of transparent space.
Speaker 2: And I guess those bubbles eventually grew.
Speaker 3: Yeah, over hundreds of millions of years, those clear bubbles expanded,
Speaker 3: they overlapped, and finally merged together to clear the entire cosmos.
Speaker 2: It is just staggering to think about. I mean, the deep,
Speaker 2: transparent vacuum of space we see today is actually the
Speaker 2: aftermath of a billion year long radiation bombardment.
Speaker 3: It's the debris field of a very long war.
Speaker 2: But if the cosmic fog didn't just passively dissipate, if
Speaker 2: it had to be violently burned away from the inside out,
Speaker 2: that means something incredibly powerful had to be doing.
Speaker 3: The burning, something very bright and very energetic.
Speaker 2: Right. But for a long time, the exact mechanism, the
Speaker 2: specific culprits that managed to pull this off, they were
Speaker 2: completely shrouded in that very same fog.
Speaker 3: It's a cruel irony. The fog hid the things that
Speaker 3: were clearing the fog exactly.
Speaker 2: Astronomers couldn't see them doing it. We knew the fog
Speaker 2: cleared eventually, but we didn't have the smoking gun, which
Speaker 2: brings us to this recently discovered, highly unlikely little galaxy
Speaker 2: that has completely changed the game.
Speaker 3: This is where the narrative really shifts. Yeah, we move
Speaker 3: from the theoretical mechanics of the early universe to a specific,
Speaker 3: astonishing hard data observation.
Speaker 2: So let's meet the cosmic underdog. It has a very catchy,
Speaker 2: memorable catalog name MXDF four point four.
Speaker 3: Rolls right off the tongue, doesn't it.
Speaker 2: Oh yeah, I'm sure someone will write a song about it.
Speaker 2: But this little galaxy existed roughly one point four billion
Speaker 2: years after the Big.
Speaker 3: Bang, and that timing is crucial.
Speaker 2: Right, because that places it right at the very tail
Speaker 2: end of this transformative era of realization. It's essentially sitting
Speaker 2: right at the finish line of this cosmic transition.
Speaker 3: Its placement in time is exactly what makes it so
Speaker 3: incredibly significant, because at one point four billion years the
Speaker 3: universe was still very much a mixed bag.
Speaker 2: What do you mean by a mixed bag?
Speaker 3: Well, the realization process was finishing up, sure, but there
Speaker 3: were still massive intercalective clouds of opaque gas everywhere, a
Speaker 3: deeply transitional.
Speaker 2: Period, so totally clear yet right.
Speaker 3: Which makes it the perfect laboratory to see this clearing
Speaker 3: process actively happening, assuming you could find a way to
Speaker 3: peer through the remaining haze to actually see the source.
Speaker 2: Which we'll get to. But when I first started looking
Speaker 2: at the profile of this galaxy MXTSC four point four,
Speaker 2: I really struggle to wrap my head around its physical scale.
Speaker 4: It's unintuitive, for sure, Yeah, because when we talk about
Speaker 4: galaxies that have the power to change the universe, we
Speaker 4: tend to picture these massive, sprawling, majestic spirals like our
Speaker 4: own Milky.
Speaker 3: Way giant pin wheels of stars exactly.
Speaker 2: But to really grasp what this ancient galaxy is doing,
Speaker 2: you have to realize how bizarre its proportions are. I
Speaker 2: actually like to compare it to a coffee machine.
Speaker 3: Okay, you're gonna have to elaborate on that. How does
Speaker 3: a twelve billion year old galaxy resemble a coffee machine?
Speaker 2: Bear with me. Think of our Milky Way galaxy as
Speaker 2: a massive, slow drip commercial coffee maker and giant diner. Okay,
Speaker 2: it is huge, It takes up a lot of space.
Speaker 2: It steadily reliably produces coffee all day long at a
Speaker 2: very measured, manageable pace. That's our galaxy right now for me,
Speaker 2: just a few new stars every single year.
Speaker 3: It's calm, it's spread out, right.
Speaker 2: But MXDFC four point four is like taking the motor
Speaker 2: of a high powered industrial espresso machine, putting it in
Speaker 2: a tiny, cramped, sealed cardboard box and running it on
Speaker 2: absolute maximum overdrive until it starts shaking itself apart.
Speaker 5: That is a very chaotic mental image, but it fits
Speaker 5: because this newly discovered galaxy is one hundred times smaller
Speaker 5: by area than our milky Way, one hundred times smaller.
Speaker 3: A tiny fraction of the size, and yet.
Speaker 2: In that microscopic, cramped space, it is churning out new
Speaker 2: stars ten times faster than we are.
Speaker 3: And taking your analogy further, it's not just an industrial
Speaker 3: espresso machine in a cardboard box. The box is filled
Speaker 3: with the raw material. It's full of the dense gas
Speaker 3: and dust required to make those stars.
Speaker 2: Right, it's completely stuff.
Speaker 3: The visual of that is incredibly chaotic, and it perfectly
Speaker 3: aligns with the physics. What you are describing is a
Speaker 3: phenomenon that the lead researcher on this discovery ilias Gubertz
Speaker 3: refers to as the crowding effect.
Speaker 2: The crowding effect.
Speaker 3: Yes, this is the fundamental secret weapon of MXDFC four
Speaker 3: point four. It isn't just that it's producing stars rapidly.
Speaker 3: It is the specific aggressive nature of those stars and
Speaker 3: the extreme proximity in which they are forced to exist.
Speaker 2: They are completely crammed together.
Speaker 3: Crammed is almost an understatement. The galaxy is forcing the
Speaker 3: creation of massive, young, incredibly hot stars into a minuscule
Speaker 3: cosmic footprint.
Speaker 2: So they're basically sitting on top of each other exactly.
Speaker 3: And furthermore, these stars aren't forming in a steady, even
Speaker 3: drip like your diner coffee maker. They form in violent, sudden.
Speaker 2: Bursts, like all at once.
Speaker 3: The data shows that a massive percentage of these highly
Speaker 3: energetic stars formed within just the last few million years
Speaker 3: of the galaxy's existence. At that point in time, it's
Speaker 3: not a slow burn at all. It is an absolute
Speaker 3: explosion of stellar birth.
Speaker 2: Wow. So you have this microscopic galaxy by cosmic standards,
Speaker 2: just packed shoulder to shoulder with the hottest, most aggressive
Speaker 2: type of stars possible, all igniting at it essentially the
Speaker 2: exact same time and.
Speaker 3: Because they are so young and incredibly massive, they are
Speaker 3: burning at surface temperatures that make our sun look like
Speaker 3: a dying ember.
Speaker 2: Just unimaginably hot.
Speaker 3: They are producing an overwhelming, blinding flood of that specific
Speaker 3: high energy ionizing ultraviolet light we talked.
Speaker 2: About earlier, the light that clears the fog.
Speaker 3: Yes, they are manufacturing the exact type of light needed
Speaker 3: to strip the electrons from the neutral hydrogen and clear
Speaker 3: the universe.
Speaker 2: Okay, but this is where my brand hits a massive roadblock.
Speaker 2: And honestly, if you're listening to this and following the
Speaker 2: logic here, I think you might be stuck in the
Speaker 2: exact same place.
Speaker 3: Let's hear the roadblock.
Speaker 2: We have this cluster of ridiculously bright hot stars in
Speaker 2: a very confined space that is a great power source.
Speaker 2: But simply having a power source isn't enough to permanently
Speaker 2: alter the fabric of the surrounding universe. True, how exactly
Speaker 2: does their light manage to break out of the galaxy itself?
Speaker 2: Because think about it. A galaxy that is forming stars
Speaker 2: that rapidly is by definition full of the raw material
Speaker 2: needed to make stars.
Speaker 3: It has to be. You can't make stars without gas.
Speaker 2: Right, It is full of dense gas and thick cosmic dust.
Speaker 2: It is choked with it.
Speaker 3: That is the pivotal question. And you've just articulated the
Speaker 3: exact paradox that has stumped astrophysicists for years when looking
Speaker 3: at these early galaxies.
Speaker 2: Because if I am standing in the middle of a thick,
Speaker 2: choking cloud of campfire smoke and I turn on a
Speaker 2: tremendously powerful military grade flashlight.
Speaker 3: It doesn't matter how strong the.
Speaker 2: Light is, exactly most of that light just hits the
Speaker 2: smoke immediately in front of me and scatters. It creates
Speaker 2: a bright, blinding wall of white right in my face.
Speaker 3: You basically blind yourself.
Speaker 2: Yeah, it physically cannot clear the air across the campsite.
Speaker 2: The smoke absorbs and deflexs it. So how on Earth
Speaker 2: does literally almost all of this ionizing light from MXDFIVEVACA
Speaker 2: four point four escape the galaxy without just getting instantly
Speaker 2: absorbed by the galaxy's own internal gas and dust.
Speaker 3: The light shouldn't be able to leave the building.
Speaker 2: It's essentially right, it should be trapped inside well.
Speaker 3: Resolving that paradox brings us to what might be the
Speaker 3: most dramatic and awe inspiring mechanism in all of astrophysics.
Speaker 3: This is the mechanics of the Great escape.
Speaker 2: The great escape.
Speaker 3: I love that your intuition is entirely correct. The light
Speaker 3: on its own, no matter how bright, would just be
Speaker 3: swallowed by the immediate dusty environment of the galaxy, So.
Speaker 2: The flesh light doesn't work on its own exactly.
Speaker 3: To get the light out, you have to physically clear
Speaker 3: a path. You have to move the smoke out of
Speaker 3: the way.
Speaker 2: And how does a galaxy move.
Speaker 3: The smoke the way MXDFZ four point four moves the
Speaker 3: smoke is through utter catastrophe.
Speaker 2: Okay, let's talk about the catastrophe. Yeah, what is physically
Speaker 2: happening to the gas inside that little box?
Speaker 3: We have to look closely at the life cycles of
Speaker 3: these specific types of massive stars in the universe. There
Speaker 3: is a brutal, unbreakable rule. The brightest, most massive stars
Speaker 3: burn out the.
Speaker 2: Fastest because they're using up their fuel so quickly.
Speaker 3: Exactly, a relatively calm star like our sun will live
Speaker 3: for about ten billion years, slowly and steadily fusing hydrogen
Speaker 3: in its core. It's very stable.
Speaker 2: Slow and steady wins the race, right.
Speaker 3: But the massive super hot stars being churned out in
Speaker 3: these violent bursts within mxdf z four point four. They
Speaker 3: are so massive and their internal gravity is crushing their
Speaker 3: cores so intensely that they burn through their nuclear fuel
Speaker 3: at an astonishing reckless rate.
Speaker 2: How fast are we talking?
Speaker 3: They live for only a few million years in cosmic terms,
Speaker 3: That is the blink of an eye.
Speaker 2: They are the rock stars of the universe. They live
Speaker 2: fast and they die extremely young.
Speaker 3: That's a perfect way to put it. And their deaths
Speaker 3: are the key to the entire mystery.
Speaker 2: What happens when they die?
Speaker 3: Well, when a star that massive inevitably runs out of fuel,
Speaker 3: the outward pressure generated by nuclear fusion suddenly stalks, and
Speaker 3: with out that outward pressure, the immense gravity of the
Speaker 3: star causes the entire core to collapse in on itself
Speaker 3: in a fraction of a second.
Speaker 2: Oh wow, just instant collapse.
Speaker 3: This incredibly violent collapse triggers a massive rebound, a shock
Speaker 3: wave of unimaginable power. They detonate a.
Speaker 2: Supernovas the ultimate cosmic explosion.
Speaker 3: Truly, the sheer physics of a supernova are hard to fathom.
Speaker 3: The kinetic energy and radiation released in a single supernova
Speaker 3: explosion is more than our sun will produce in its
Speaker 3: entire ten billion year lifetime, all unleashed in a matter
Speaker 3: of days.
Speaker 2: That is, I can't even picture that level of energy.
Speaker 3: Now, recall the crowding effect we discussed earlier. You don't
Speaker 3: just have one single star doing this. You have a massive,
Speaker 3: crammed cluster of these giant.
Speaker 2: Stars, right because they all formed in that sudden burst exactly.
Speaker 3: They were all born at roughly the same time during
Speaker 3: that starburs phase, which means they are going to die
Speaker 3: at roughly the same time.
Speaker 2: Oh my god. So it's just a chain reaction of
Speaker 2: detonations inside a confined space.
Speaker 3: It is a relentless, catast strophic bombardment from the inside.
Speaker 3: These supernovas are releasing gigantic amounts of kinetic energy and
Speaker 3: extreme radiation pressure.
Speaker 2: And that pressure pushes the gas.
Speaker 3: It doesn't just push it. They are literally physically blowing
Speaker 3: colossal holes through the opaque gas and dust of their
Speaker 3: own galaxy. They are sweeping the raw material away, carving
Speaker 3: out massive empty cavity.
Speaker 2: Like blasting tunnels through a mountain.
Speaker 3: Exactly like that. They're essentially building structural chimneys that lead
Speaker 3: from the dense, dusty core of the star cluster straight
Speaker 3: out into the intergalactic medium.
Speaker 2: So let me make sure I have this sequence right.
Speaker 2: The first generation of these massive stars in the burst,
Speaker 2: they live their short lives, they explode, and they act
Speaker 2: as a heavy demolition crew spot on. They physically blow
Speaker 2: away the internal fog of the galaxy, creating these clear,
Speaker 2: empty physical pathways. And then the light from the surviving
Speaker 2: young stars or maybe the very next immediate wave of
Speaker 2: stars that form. Yes, that light can just shoot straight
Speaker 2: out through those excavated chimneys, entirely unobstructed by dust or gas.
Speaker 3: That is the exact mechanism. It's brilliant in its violence.
Speaker 3: Researchers looking at the data for MXDFC four point four
Speaker 3: estimate that an astonishing fifty percent to one hundred percent
Speaker 3: of the young star's energetic ionizing light is successfully escaping
Speaker 3: the surrounding gas of the galaxy.
Speaker 2: I want to pause on that number, yeah, because when
Speaker 2: you say fifty to one hundred percent, my IMDIA thought
Speaker 2: is Okay, that's a lot. Yeah, but I don't really
Speaker 2: have a baseline for what is normal.
Speaker 3: The baseline is what makes that number truly shocking. What's
Speaker 3: the baseline in a normal, present day spiral galaxy like
Speaker 3: our Milky Way. The escape fraction for this kind of
Speaker 3: high energy ionizing light is typically around one percent, maybe even.
Speaker 2: Less one percent.
Speaker 3: Yeah, almost all of the high energy light produced in
Speaker 3: our galaxy gets absorbed locally by our own gas and dust.
Speaker 2: So to have potentially one hundred percent of that light
Speaker 2: breaking free from MXCFC four point four, it.
Speaker 3: Means the internal structure of that galaxy has been completely
Speaker 3: shredded and hollowed out by the supernova.
Speaker 2: Winds, totally excavated.
Speaker 3: Think about how violent an environment has to be to
Speaker 3: have literally zero internal resistance to light. It is a
Speaker 3: perfect violent storm of intense radiation paired with explosive physical clearing.
Speaker 2: It is the definitive escape vehicle for the light that
Speaker 2: changed the universe. Absolutely, the very act of these massive
Speaker 2: stars dying is what allows the light to escape and
Speaker 2: clear the cosmic fog for the rest of the universe.
Speaker 2: There's almost a poetic beauty to that kind of destruction.
Speaker 3: Life from death essentially, or at least light from death.
Speaker 2: Right But taking a step back, this also raises a
Speaker 2: massive logistical problem for the people actually trying to study it.
Speaker 3: Oh, Definitely, the observation side is a whole other mountain
Speaker 3: to climb.
Speaker 2: Yeah, because if you're listening to this and keeping track
Speaker 2: of the timeline, Astronomers for years assumed that observing this breakout,
Speaker 2: observing a galaxy actively pouring this much ultraviolet light into
Speaker 2: the early universe was completely impossible.
Speaker 3: It was considered a lost cause for a.
Speaker 2: Long time because by death Phinian, the universe surrounding the
Speaker 2: galaxy at that exact time was still filled with that
Speaker 2: neutral hydrogen fog. The indrigalactic fog should have absorbed all
Speaker 2: the events before it ever traveled the twelve billion light
Speaker 2: years to reach our telescopes.
Speaker 3: A light should have never made it.
Speaker 2: To Earth exactly, So how did humanity manage to capture
Speaker 2: light from a time when the universe itself was actively
Speaker 2: trying to hide it?
Speaker 3: Well, the observation of MXDSC four point four wasn't just
Speaker 3: a matter of pointing a big telescope at the sky
Speaker 3: and getting lucky.
Speaker 2: Imagine not.
Speaker 3: It required a perfectly synchronized effort, an unprecedented astronomical tag
Speaker 3: team between three of the most sophisticated observatories ever built
Speaker 3: by humanity.
Speaker 2: This is where the story feels less like traditional astronomy
Speaker 2: and more like a high space, incredibly complex investigation.
Speaker 3: I love that framing.
Speaker 2: Yeah, if you'll indulge me, I frame this for myself
Speaker 2: as a team of highly specialized detectives working the ultimate cold.
Speaker 3: Case, a twelve billion year old cold case.
Speaker 2: Exactly. You have three distinct experts brought into all the crime.
Speaker 2: You have the Hubble Space telescope, you have the James
Speaker 2: web Space telescope, and you have the European Southern Observatory
Speaker 2: is Very Large Telescope.
Speaker 3: Or VLT, the heavy hitters, and.
Speaker 2: They all played entirely different, absolutely necessary roles. So let's
Speaker 2: start with Hubble. In my detective analogy, Hubble is the
Speaker 2: high speed photographer who somehow manages to catch the actual
Speaker 2: breakout of light in action.
Speaker 3: And Hubble's ability to catch that breakout is entirely dependent
Speaker 3: on a fundamental cosmic phenomenon called redshifting. Understanding redshifting is
Speaker 3: crucial to understanding why observing this galaxy is a literal
Speaker 3: miracle of physics.
Speaker 2: Okay, so if you're listening to this and wondering why
Speaker 2: scientists don't just use standard Earth based optical telescopes to
Speaker 2: look at these old galaxies, this is where the physics
Speaker 2: of the universe gets incredibly weird.
Speaker 3: Super weird. Let's really break down redshifting go for it.
Speaker 3: Remember that the light escaping from MXDFC four point four,
Speaker 3: the light doing the work of clearing the fog, is
Speaker 3: high energy ultraviolet light.
Speaker 2: The stuff that causes sunburns.
Speaker 3: Basically right, but way more intense. If you were floating
Speaker 3: in space right next to that galaxy one point four
Speaker 3: billion years after the Big Bang and you had a
Speaker 3: sensor for UV light, it would be blindingly intense. Okay,
Speaker 3: but that specific light has to travel for over twelve
Speaker 3: billion years to reach Earth, and over those twelve billion years,
Speaker 3: the universe is not a static empty room because.
Speaker 2: The universe itself is physically expanding.
Speaker 3: Exactly, and as the fabric of space stretches, the waves
Speaker 3: of light traveling through that space get physically stretched along
Speaker 3: with it.
Speaker 2: Wait, the actual light wave stretch.
Speaker 3: The actual waves.
Speaker 2: Yeah.
Speaker 3: The classic way to visualize this is drawing a wavy
Speaker 3: line on a rubber band and then pulling the ends
Speaker 3: of the rubber band. Ah Okay, the waves get longer
Speaker 3: and more drawn out as the band stretches.
Speaker 2: Precisely the peaks and valleys of the light wave get
Speaker 2: further and further apart.
Speaker 3: And why does that matter.
Speaker 2: Well, in the electromagnetic spectrum, the distance between those peaks
Speaker 2: the wavelength determines both the color and the energy of
Speaker 2: the light.
Speaker 3: Okay, So a shorter wave is one color, a longer
Speaker 3: wave is another, right.
Speaker 2: And a longer wavelength means lower energy. So, over its
Speaker 2: twelve billion year journey through expanding space, that incredibly tight
Speaker 2: energetic ultraviolet wave gets stretched so much that it actually
Speaker 2: shifts out of the ultraviolet spectrum entirely.
Speaker 3: It changes completely, it does.
Speaker 2: By the time it finally hits the mirrors of our
Speaker 2: telescopes today, it has been stretched all the way into
Speaker 2: the visible light spectrum.
Speaker 3: The exact light we can see with our own eyes exactly.
Speaker 3: That is genuinely mind bending. The light started as invisible
Speaker 3: high energy UV rode the physical expansion of the universe
Speaker 3: like a massive cosmic conveyor belt and stretched into visible colors.
Speaker 2: It's one of the most elegant quarks of our universe.
Speaker 2: And this is precisely why Hubble was the only tool
Speaker 2: for the job to see it right.
Speaker 3: Yes, Hubble is perfectly optimized to see invisible and near
Speaker 3: ultraviolet light. But it's not just the wavelength coverage that
Speaker 3: matters here. It is Bubble's space based location, its sensitivity,
Speaker 3: and its unbelievable optical resolution.
Speaker 2: Because it's so tiny and so far away.
Speaker 3: Right, looking at a tiny, cramped galaxy that is twelve
Speaker 3: billion light years away requires incredibly long, deep exposures. Hubble
Speaker 3: literally stared at this specific patch of sky for immense periods,
Speaker 3: gathering ancient photons one by one from several existing deep
Speaker 3: field surveys.
Speaker 2: So it just slowly built up the picture.
Speaker 3: Yeah, it was the only instrument capable of resolving the
Speaker 3: specific source of that incredibly faint red shifted light and
Speaker 3: physically proving that it was coming directly from the tight
Speaker 3: clusters of young stars inside that galaxy.
Speaker 2: So Hubble gets the picture. It proves the light as escaping.
Speaker 2: But if Hubble is the photographer, the James Web Space
Speaker 2: Telescope is the psychological profiler. That's a good way to
Speaker 2: put it, because Mark Riffelski, a co author on this study,
Speaker 2: explicitly noted that without Web, the Hubble data would essentially
Speaker 2: be useless.
Speaker 3: Useless is a strong word, but in this context it's accurate.
Speaker 2: But why is that? If Hubble already saw the light escaping.
Speaker 2: Why did we need Web to step in and look
Speaker 2: at the exact same galaxy? What was missing?
Speaker 3: Well, seeing the light escaping doesn't tell you the whole
Speaker 3: story of the galaxy that produced it. You need environmental context.
Speaker 3: You need to know the specific conditions that allowed that
Speaker 3: light to.
Speaker 2: Escape, like the state of the smoke in the room exactly.
Speaker 3: Hubble is fantastic for visible light, but as we discussed,
Speaker 3: these heavily active star forming galaxies are absolutely full of dust,
Speaker 3: and cosmic dust notoriously blocks visible light.
Speaker 2: It obscures the internal structure completely.
Speaker 3: To really see what the galaxy looks like inside, to
Speaker 3: weigh its total mass, and to map out its entire
Speaker 3: history of star formation, you have to find a way
Speaker 3: to look straight through the dust.
Speaker 2: And that is Web's ultimate superpower.
Speaker 3: It is Web operates primarily in the near infrared and
Speaker 3: mid infrared spectrum. Infrared light has a much longer wavelength
Speaker 3: than visible.
Speaker 2: Light, which means it behaves differently.
Speaker 3: It allows the light to slip right around and through
Speaker 3: thick clouds of cosmic dusts that would otherwise be completely
Speaker 3: impenetrable to a telescope like Hubble.
Speaker 2: Wow, it's basically X ray vision for dust.
Speaker 3: Essentially. Yeah, So Webb looked at the exact same tiny
Speaker 3: galaxy and was able to determine the total mass of
Speaker 3: the structure. But more importantly, it was able to look
Speaker 3: at the older generations of stars that Hubble couldn't clearly
Speaker 3: define because they were hidden.
Speaker 2: Ah So Web analyzes the suspects. It looks at the
Speaker 2: entire population of the galaxy, not just the bright young ones.
Speaker 3: And that WEB data was the absolute nail in the
Speaker 3: coffin for determining the mechanism of the great escape. Howso,
Speaker 3: by analyzing the infrared data, Web proved that the older
Speaker 3: stars in MXDSC four point four were significantly cooler and
Speaker 3: less massive than the new burst.
Speaker 2: They were just two weak exactly.
Speaker 3: It definitively proved that these older populations were totally incapable
Speaker 3: of producing the energy required to blow away the gas
Speaker 3: or ionize the surrounding universe.
Speaker 2: They didn't have the muscle.
Speaker 3: By mathematically ruling out the older stars, Webb confirmed that
Speaker 3: the recent violent bursts of massive young stars, the ones
Speaker 3: Hubble caught, were the sole culprits responsible.
Speaker 2: It mapped the star formation history and proved the bursting
Speaker 2: explosive nature of the galaxy.
Speaker 3: It gave us the motive and the means.
Speaker 2: The synergy between the two space telescopes is incredible. Hubble
Speaker 2: sees the smoke clearing and Web looks through the walls
Speaker 2: to prove exactly who planted the dynamite.
Speaker 3: It really is a perfect partnership.
Speaker 2: But we have one more detective on the team, and
Speaker 2: their role is just as vital. The European Southern Observatory's
Speaker 2: Very Large Telescope, specifically the Meuse Instrument, the VLT. I
Speaker 2: call the VLT the forensic accountant because it didn't just
Speaker 2: look at the galaxy. It pinpointed the exact, undeniable timeline
Speaker 2: of the crime.
Speaker 3: And precision is everything in cosmology, it really is. If
Speaker 3: you don't know exactly when an event happened, you can't
Speaker 3: place it in the sequence of the universe's evolution. You're
Speaker 3: just guessing, right.
Speaker 2: And the VLT is a massive ground based facility in Chile,
Speaker 2: but the MUSE instrument attached to it is an incredibly
Speaker 2: powerful spectrograph operating in visible light.
Speaker 3: The spectrograph is the key here, So.
Speaker 2: Let's spend a minute on how a spectrograph actually works.
Speaker 2: Because it's essentially the most important tool in astronomy, right.
Speaker 3: Oh, absolutely, we'd be blind without them.
Speaker 2: From my understanding, a spectrograph takes the incoming light from
Speaker 2: that distant galaxy and physically breaks it apart into its
Speaker 2: component colors, like a highly advanced, incredibly precise prism.
Speaker 3: That's a perfect description. And breaking the light apart allows
Speaker 3: you to look at the quantum fingerprints of the galaxy.
Speaker 2: What do you mean by quantum fingerprints.
Speaker 3: Well, when you spread the light out into a spectrum,
Speaker 3: you don't just see a smooth rainbow of colors. You
Speaker 3: see these tiny dark gaps in the colors.
Speaker 2: Like missing slices.
Speaker 3: Right. These are called absorption lines different chemical elements in
Speaker 3: the universe, like hydrogen, helium, or carbon. They absorb very specific,
Speaker 3: exact wavelengths of light.
Speaker 2: So when the light travels through.
Speaker 3: The gas, exactly when light passes through the gas of
Speaker 3: a galaxy, the elements in that gas steal those specific colors,
Speaker 3: leaving dark gaps in the spectrum that reaches our telescopes.
Speaker 2: It's like a barcode. Every element has a unique barcode
Speaker 2: of dark lines.
Speaker 3: It is exactly like a barcode, and we know exactly
Speaker 3: where those dark lines should be for a specific element
Speaker 3: if it were sitting in a laboratory here on Earth.
Speaker 3: But remember red shifting. Because the light from MXDFC four
Speaker 3: point four has been stretched by the expansion of the
Speaker 3: universe for twelve billion years, that entire barcode is shifted
Speaker 3: toward the red end of the spectrum.
Speaker 2: Oh I see, so the whole barcode slides over. And
Speaker 2: they just measured exactly how much the barcode had been stretched.
Speaker 3: Precisely by looking at those specific absorption lines, the MUSC
Speaker 3: instrument could calculate the exact mathematical degree of the red shift.
Speaker 2: Wow.
Speaker 3: And by knowing precisely how much the light had stretched,
Speaker 3: they could plug that into our models of cosmic expansion
Speaker 3: and calculate exactly how long the light had been traveling.
Speaker 2: Brilliant.
Speaker 3: This is how they pinpointed the exact age of MXDFC
Speaker 3: four point four at one point four billion years post.
Speaker 2: Big Bang down to the decimal. Yeah.
Speaker 3: Without that highly specific timestamp from the VLT, we wouldn't
Speaker 3: know exactly where this little galaxy fits into the timeline
Speaker 3: of the era of realization. For all we knew, it
Speaker 3: could have been from a time when the fog was
Speaker 3: already cleared.
Speaker 2: It truly is a masterpiece of technological coordination. I mean,
Speaker 2: you have a telescope launched in the nineteen.
Speaker 3: Nineties Hubble still going strong.
Speaker 2: Yeah, a brand new infrared powerhouse parked a million miles
Speaker 2: away from Earth, and a massive ground based array in
Speaker 2: the Chilean Desert, all combining their unique, highly specialized data
Speaker 2: streams to build a single, undeniable picture of an event
Speaker 2: that happened twelve billion years ago.
Speaker 3: It gives you goosebumps when you really think about.
Speaker 2: It, It really does. But this rais is a really
Speaker 2: important question, and I think it's where we need to
Speaker 2: look at how this reshapes our understanding of the whole universe.
Speaker 3: Okay, let's look at the big picture.
Speaker 2: Because this massive, unprecedented effort yielded a single, spectacular observation
Speaker 2: of one tiny galaxy, why is this one little underdog
Speaker 2: causing such a massive paradigm shift in how we understand
Speaker 2: the cosmos?
Speaker 3: Well, in the field of cosmology, single concrete data points
Speaker 3: from that far back in time are incredibly rare, really
Speaker 3: just hard to find, very hard. They are the structural
Speaker 3: anchors that hold our massive theoretical models in reality. You see,
Speaker 3: prior to the discovery and deep analysis of MXDFC four
Speaker 3: point four, the cosmic map of the realization era was
Speaker 3: largely drawn using statistical assumptions.
Speaker 2: Okay, when you say statistical assumptions, what do you actually mean.
Speaker 2: Are astrophysicists just making highly educated guesses.
Speaker 3: It is a bit more rigorous than a guess, but essentially, yes,
Speaker 3: far enough. Researchers have been trying to understand this era
Speaker 3: for decades. But because these early galaxies are so impossibly
Speaker 3: distant and faint, they simply couldn't observe the mechanics directly.
Speaker 2: The fog hid them.
Speaker 3: So what is the alternative. You look at star populations
Speaker 3: in nearby galaxies, galaxies that are close enough to observe
Speaker 3: in great detail, and you use the statistics of how
Speaker 3: they behave.
Speaker 2: Like how rapidly they form stars, how their internal gas moves,
Speaker 2: that sort.
Speaker 3: Of thing exactly. You take those modern observations and use
Speaker 3: them to make well informed assumptions about what must have
Speaker 3: been happening in the early universe.
Speaker 2: Ah, so you extrapolate backward. You say, if physics works
Speaker 2: like this here and now in this specific type of
Speaker 2: star cluster, it probably works somewhat like this twelve billion
Speaker 2: years ago.
Speaker 3: That is the foundation of the theoretical models. But a
Speaker 3: model is always an assumption until you find hard empirical
Speaker 3: evidence to back it up.
Speaker 2: You need proof, You need proof.
Speaker 3: Before MXDFC four point four, researchers had only ever found
Speaker 3: one single galaxy emitting ionized light from one point six
Speaker 3: billion years ago, just one, just one, and maybe a
Speaker 3: few scattered examples from around two billion years ago, which
Speaker 3: is a point in time when the cosmic fog was
Speaker 3: mostly already cleared anyway.
Speaker 2: So they didn't really help explain the clearing process.
Speaker 3: That's right, MXDFC four point four, sitting right at the
Speaker 3: critical juncture of one point four billion years provides clear,
Speaker 3: undeniable proof of extreme ionizing light escaping. It completely anchors
Speaker 3: those theoretical models.
Speaker 2: It proves that the assumed mechanics actually existed in reality.
Speaker 3: Yes, it takes it out of the realm of simulation
Speaker 3: and into the realm of fact.
Speaker 2: Now I want to play skeptic here for the listener,
Speaker 2: because there is a seeming contradiction in the timeline of
Speaker 2: recent astronomical discoveries that I need you to clear up. Okay,
Speaker 2: laying on me in twenty twenty three. Just recently, there
Speaker 2: were massive headlines globally because the James Web space telescopes
Speaker 2: looked incredibly far back and proved that galaxies had stars
Speaker 2: emitting enough light to heat and ionized gas just nine
Speaker 2: hundred million years after the Big Bang.
Speaker 3: That was a huge moment, Yes, right.
Speaker 2: But that is half a billion years older than our
Speaker 2: little underdog galaxy. If we already knew from Web in
Speaker 2: twenty twenty three that galaxies had the power to do
Speaker 2: this back, then, why is this one point four billion
Speaker 2: year old galaxy the big missing puzzle piece.
Speaker 3: It's a very fair point to raise.
Speaker 2: Didn't Web already solve the mystery of reionization.
Speaker 3: Distinguishing between those two discoveries cuts to the very heart
Speaker 3: of how science actually progresses. It is the fundamental difference
Speaker 3: between having the potential to do something and actually executing
Speaker 3: on that potential.
Speaker 2: Break that down force. What did the twenty twenty three
Speaker 2: discovery actually tell us.
Speaker 3: The twenty twenty three breakthrough with Web was absolutely monumental,
Speaker 3: no doubt, looking back to nine hundred million years and
Speaker 3: seeing the light from those incredibly early galaxies was a
Speaker 3: triumph of engineering.
Speaker 2: Roqu records it did.
Speaker 3: What WEB proved in twenty twenty three was that the
Speaker 3: sheer volume of high energy light existed in the early universe.
Speaker 3: It proved that the universe was manufacturing the right kind
Speaker 3: of ammunition.
Speaker 2: The stars were burning hot enough and bright enough to
Speaker 2: potentially clear the neutral hydrogen fogs.
Speaker 3: Yes, they had the power source, they possessed the required energy. However,
Speaker 3: there's always a however there is. However, what that twenty
Speaker 3: twenty three ARE observation completely failed to explain was the
Speaker 3: mechanism of escape. It showed the light was being created
Speaker 3: deep inside the galaxies, but it couldn't show how that
Speaker 3: light survived long enough to escape the thick choking gas
Speaker 3: of the galaxy itself to reach the intergalactic fog.
Speaker 2: Oh Man. So, returning to the flashlight in the campfire
Speaker 2: smoke analogy, the twenty twenty three WEB observation proved the
Speaker 2: flashlight was turned on exactly, It did not prove how
Speaker 2: the light got out of the smoke to clear the
Speaker 2: rest of the forest.
Speaker 3: That is exactly right. We knew the engines were running
Speaker 3: inside the factory, but we didn't know how the exhaust
Speaker 3: was getting out of the building.
Speaker 2: That makes perfect sense.
Speaker 3: MXDSZ four point four is the first concrete, undeniable proof
Speaker 3: of the mechanism.
Speaker 2: It is the how by combining of the Hubble data
Speaker 2: showing the escaping light with the web data showing the
Speaker 2: bursting nature of the star formation.
Speaker 3: Yes, it proves that the mechanism of escape is violence.
Speaker 3: It proves that bursting crammed star formations and the resulting
Speaker 3: catastrophic supernovas act as the physical escape vehicle for this light.
Speaker 2: It validates the entire working theory of how the universe
Speaker 2: cleared its throat, so to speak.
Speaker 3: The twenty twenty three data showed the what. MXDSC four
Speaker 3: point four proves the how, and in the scientific method,
Speaker 3: proving the how is what actually rewrites the textbooks.
Speaker 2: It takes the theory out of the realm of statistical
Speaker 2: assumption and grounds it firmly in observable mechanical reality.
Speaker 3: You couldn't ask for a better piece of evidence.
Speaker 2: So where do we go from here? If this single
Speaker 2: galaxy is the Rosetta stone that proves how the fog
Speaker 2: was lifted, what is the roadmap forward for the astronomical community.
Speaker 3: Well, we don't just stop looking.
Speaker 2: Do we just start scanning the sky hoping to trip
Speaker 2: over more of these little hyperactive espresso machines.
Speaker 3: It will be a highly targeted, deliberate search because the
Speaker 3: discovery of MXDFC four point four proves that these objects
Speaker 3: exist and crucially that our current instruments are capable of
Speaker 3: finding them if we know where and how to look.
Speaker 2: So the immediate future outlook involves aggressively searching for more
Speaker 2: gas galaxies that share these specific characteristics. Precisely, our research
Speaker 2: is going to try to look even further back in time,
Speaker 2: deeper into the dark ages.
Speaker 3: Interestingly, the strategy outlined by the researchers is to actually
Speaker 3: find more of these galaxies at slightly later cosmic times.
Speaker 2: Wait really, why later? Yeah, wouldn't we want to look
Speaker 2: deeper into the fog to see the very beginning of
Speaker 2: the process.
Speaker 3: You would think so, But it's a matter of practicality,
Speaker 3: sample size, and signal strength. By looking at slightly later
Speaker 3: cosmic times, say moving from one point four billion years
Speaker 3: toward two billion years, the galaxies are slightly closer.
Speaker 2: To us, which means their light is slightly less red.
Speaker 3: Shifted exactly, and they are significantly easier to detect with
Speaker 3: high fidelity. The overarching goal right now is to build
Speaker 3: a larger statistical sample size of concrete data.
Speaker 2: Because we don't want to base our entire understanding of
Speaker 2: cosmic evolution on one single galaxy, no matter how spectacular
Speaker 2: and insightful it is.
Speaker 3: Right, you need a pattern, not just an anomaly. By
Speaker 3: finding ten or fifty or a hundred of these bursting
Speaker 3: fog clearing galaxies at various stages of the late reionization era,
Speaker 3: researchers can drastically refine their measurements.
Speaker 2: They can start to see if this violent supernova driven
Speaker 2: clearing is the only way it happens, or if it's
Speaker 2: just one of many different ways the universe became transparent.
Speaker 3: They can figure out exactly what percentage of the cosmic
Speaker 3: fog was cleared by these violent little underdogs versus larger,
Speaker 3: more stable galaxies that might have different escape mechanisms.
Speaker 2: Gathering a large sample size allows them to finally draw firm,
Speaker 2: unquestionable conclusions about the exact timeline, the dominant mechanisms, and
Speaker 2: the definitive end of the era of realization.
Speaker 3: It transitions the field from an era of incredible singular
Speaker 3: discoveries into an era of precision mapping and comprehensive understanding.
Speaker 2: It is truly staggering to step back and look at
Speaker 2: the sheer scope of what we've discussed today.
Speaker 3: It's a lot to take in.
Speaker 2: It is. We started by picturing a universe completely choked
Speaker 2: by an opaque, murky fog of neutral hydrogen gas, a
Speaker 2: universe where high energy light was constantly trapped, scattered, and
Speaker 2: destroyed before it could travel any meaningful.
Speaker 3: Distance, a very dark place.
Speaker 2: And we watched as a tiny, hyperactive, chaotic galaxy managed
Speaker 2: to fight back against that darkness. It didn't fight back
Speaker 2: with steady, calm, reliable light, but with violent birthing generations
Speaker 2: of massive stars that lived incredibly short lives and died
Speaker 2: in catastrophic supernova explosions.
Speaker 3: Literally blowing physical holes through the dense cosmic dust.
Speaker 2: Carving out clearings for their light to finally escape. And
Speaker 2: all of this complex cosmic machinery was only revealed to
Speaker 2: us because three of the most advanced pieces of technology
Speaker 2: in human history, hubble Web and the VLT worked together
Speaker 2: in perfect synergy.
Speaker 3: To catch the stretched, exhausted light of that ancient battle.
Speaker 3: Twelve billion years later.
Speaker 2: It stands as a testament to both the sheer terrifying
Speaker 2: power of the natural universe and the relentless collaborative ingenuity
Speaker 2: of human curiosity.
Speaker 3: We are essentially doing forensic archaeology on the scale of
Speaker 3: the cosmos, piecing together our own origins from the faintest
Speaker 3: whispers of light.
Speaker 2: I want to leave you with a final thought to
Speaker 2: mull over today, something that really struck a chord with
Speaker 2: me as we were piecing all of this together. Okay,
Speaker 2: we started by asking you to look up at the
Speaker 2: clear ninth sky. We revel in that transparency. We build
Speaker 2: our telescopes, we map the constellations, we search for other
Speaker 2: habitable worlds, all because we have the immense privilege of
Speaker 2: a clear view into the deep cosmos.
Speaker 3: It's something we completely take for granted.
Speaker 2: Completely, but when you truly look at the mechanics of
Speaker 2: how that clear view is achieved, it fundamentally changes how
Speaker 2: you look at the stars. The very mechanism that cleared
Speaker 2: the cosmic fog, the exact physical process that made the
Speaker 2: universe transparent and allowed light to travel freely to our eyes,
Speaker 2: was the violent explosive death of its earliest most massive stars.
Speaker 3: The supernovas were the key to our site.
Speaker 2: The ultimate destruction of those ancient giants was physically required
Speaker 2: to blow away the fog, which means that the clear,
Speaker 2: beautiful night sky you look up at today, the pristine
Speaker 2: window that gives humanity our place in the cosmos, is
Speaker 2: essentially built upon the explosive graveyard of the universe's first inhabitants.
Speaker 3: Wow, that's heavy.
Speaker 2: Our ability to see the universe at all was bought
Speaker 2: entirely by their violent destruction. Keep looking up and we'll
Speaker 2: catch it next time.