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 imagine an object that is just
Speaker 2: so unbelievably dense, possessing such an incomprehensible amount of mass
Speaker 2: that it weighs a billion times more than our own.
Speaker 3: Sun, which is I mean, it's a scale. It just
Speaker 3: totally defies human intuition.
Speaker 2: Right, it breaks your brain a little bit. Yeah, But
Speaker 2: take that image, that unimaginable behemoth, and I want you
Speaker 2: to put a second one right next to it. Oh man, Yeah,
Speaker 2: picture of these two galactic giants and they're locked in
Speaker 2: this high speed, inescapable binary orbit, just whipping around each other,
Speaker 2: mere moments away from a cosmic collision that is literally
Speaker 2: going to warp the foundational architecture of the universe itself.
Speaker 3: The kinetic energy and the gravitational forces involved at that scale, well,
Speaker 3: we are talking about the physical deformation of space time.
Speaker 3: Here it's being stretched and squeezed by two super massive
Speaker 3: objects in their final inspiral phase.
Speaker 2: And as of April twenty twenty six, this whole scenario
Speaker 2: has moved entirely out of the realm of theoretical modeling. Like,
Speaker 2: we aren't just guessing.
Speaker 3: Anymore, No, not at all.
Speaker 2: We have the data exactly. We are looking directly at
Speaker 2: the galaxy Marcian five oh one or MERK five oh one,
Speaker 2: which is positioned in the constellation Hercules.
Speaker 3: Right about four hundred and fifty six million light years away.
Speaker 2: And researchers have uncovered the very first direct, unambiguous evidence
Speaker 2: of a close pair of supermassive black holes on the
Speaker 2: absolute brink of merging.
Speaker 3: Which is huge because catching a binary system in this
Speaker 3: specific final act, it's been this decades long pursuit in astrophysics.
Speaker 2: We're going to completely unpack this today. We're going to
Speaker 2: map out the life cycle of these central galactic objects.
Speaker 2: Look really closely at the twenty three year long radio
Speaker 2: astronomy stakeout that cracked this specific system open, a.
Speaker 3: Literal stakeout, just staring at this galaxy for over two decades.
Speaker 2: Yeah, and we'll break down how the impending collision of
Speaker 2: Mercle five oh one is forcing this massive pivot in
Speaker 2: how we actually do astronomy, because when telescopes hit a
Speaker 2: hard physical wall, tracking a merger like this means we
Speaker 2: have to measure the gravity itself exactly.
Speaker 3: We basically have to transition from electromagnetic observation to gravitational
Speaker 3: wave tracking. It's the only way forward when they get
Speaker 3: this close.
Speaker 2: So before we get into the crazy mechanics of the
Speaker 2: collision in Marcarian five oh one, we really have to
Speaker 2: look at why this merger has to happen in the
Speaker 2: first place.
Speaker 3: The weight problem, right, the accretion problem. It's one of
Speaker 3: the sharpest constraints we have in black hole astrophysics.
Speaker 2: Because if you look at the mass of these objects
Speaker 2: hundreds of millions, sometimes billions of solar masses, the standard
Speaker 2: models of how they eat or to crete matter, they
Speaker 2: just failed to explain how they got so big within
Speaker 2: the teen point eight billion year timeline of the universe.
Speaker 3: Yeah, we know that supermassive black holes reside at the
Speaker 3: center of virtually every large galaxy. I mean, we have
Speaker 3: a Sagittarius, a star right in the middle of our
Speaker 3: own milky way.
Speaker 2: But they can't just grow infinitely fast, right Like. As
Speaker 2: matter spirals inward, it forms that accretion disk.
Speaker 3: Yeah, and viscous friction heats that material up to extreme temperatures.
Speaker 3: It emits intense radiation.
Speaker 2: And that radiation actually exerts outward pressure, doesn't it. Precisely
Speaker 2: it pushes back the Eddington limit.
Speaker 3: Yes, the Eddington limit. It's this physical threshold where the
Speaker 3: outward radiation pressure of that glowing disk perfectly balances the
Speaker 3: inward gravitational pull of the black hole.
Speaker 2: So it's essentially a speed limit for eating.
Speaker 3: That's a great way to put it. If the mass
Speaker 3: flowing in exceeds that Eddington limit, the radiation pressure just
Speaker 3: blows all the surrounding gas and dust away.
Speaker 2: Wow.
Speaker 3: Yeah, it completely cuts off the black hole's fuel supply.
Speaker 3: So it's an inherent self regulating mechanism. It strictly limits
Speaker 3: how fast ap black hole can grow just by pulling
Speaker 3: in gas.
Speaker 2: So if you calculate the maximum theoretical growth rate from
Speaker 2: a tiny stellar mass seed black hole up to a
Speaker 2: billion solar masses, keeping that speed limit in mind.
Speaker 3: The universe simply isn't old enough.
Speaker 2: It's just not It's like trying to explain how someone
Speaker 2: ate an entire elephant and realizing they couldn't possibly do
Speaker 2: it one bite at a time. They must have just
Speaker 2: absorbed another giant eater.
Speaker 3: Huh, exactly. The math absolutely requires a shortcut. You don't
Speaker 3: build a billion solar mass black hole by pulling in
Speaker 3: interstellar gas slowly over time.
Speaker 2: You build it by smashing two five hundred million solar
Speaker 2: mass black holes together.
Speaker 3: Right, hierarchical merging, which integrates perfectly with our models of
Speaker 3: how the universe is structure formed. Galaxies collide and merge
Speaker 3: all the.
Speaker 2: Time, and when they do, their central supermassive black holes
Speaker 2: are dragged along for the ride.
Speaker 3: Yeah, they're subjected to something called dynamical friction. They interact
Speaker 3: gravitationally with the surrounding sea of star and gas in
Speaker 3: the new, bigger galaxy.
Speaker 2: This sort of bounce around and lose energy.
Speaker 3: Basically, they transfer some of their orbital kinetic energy to
Speaker 3: the stars, flinging those stars outward, which means the black
Speaker 3: holes themselves lose energy. They sink toward the center and
Speaker 3: eventually form a binary pair.
Speaker 2: Okay, but if galaxy collisions are so commonplace, why has
Speaker 2: this final close pair phase completely eluded our detection until
Speaker 2: right now. What makes his final phase so impossible to see?
Speaker 3: Well, the theory hits a massive bottleneck right there. It's
Speaker 3: why finding the Murk five oh one binary is such
Speaker 3: a breakthrough. Dynamical friction works incredibly well at large distances.
Speaker 3: It brings the black holes from the outskirts down to
Speaker 3: the core. But once they get within about one parsec
Speaker 3: of each other.
Speaker 2: Which is roughly what three point two late.
Speaker 3: Years, yeah about that. Once they hit that one parsec distance,
Speaker 3: the mechanism just breaks down entirely. It's called the final
Speaker 3: parsec problem.
Speaker 2: The loss cone depletion.
Speaker 3: Right exactly, by the time they're that close, they've acted
Speaker 3: like a massive gravitational slingshot. They've ejected almost all the
Speaker 3: stars in their immediate vicinity.
Speaker 2: So the lost cone, the area where stars could intersect
Speaker 2: their orbit, it just empties out.
Speaker 3: It becomes completely barren, and without any more stars to
Speaker 3: interact with, the dynamical friction.
Speaker 2: Just stops, so the orbital of the case stalls out.
Speaker 2: They're stuck.
Speaker 3: They're completely stuck. Theoretically, they could just orbit each other indefinitely,
Speaker 3: separated by a single parsec, totally unable to close that
Speaker 3: final gap because there is nothing left to bleed off
Speaker 3: their momentum.
Speaker 2: Wow. So to overcome that final parsec you need something.
Speaker 3: Extreme right, either a massive influx of new gas to
Speaker 3: provide viscous drag like a wet merger, or a third
Speaker 3: super massive black hole crashing the party from a subsequent
Speaker 3: galactic collision, just.
Speaker 2: To destabilize things enough to get them closer.
Speaker 3: Yes, because only when they cross that final parsec threshold
Speaker 3: can they get close enough for gravitational wave emission to
Speaker 3: take over. That becomes the new primary way they lose energy, which.
Speaker 2: Really brings into focus why to detecting this system mcfive
Speaker 2: Oh one is just so profound. We aren't just looking
Speaker 2: at a binary system. We're looking at a system that
Speaker 2: has actually successfully navigated that final parsec problem exactly.
Speaker 3: It's past the bottleneck. It is deep into the gravitational
Speaker 3: wave emission regime.
Speaker 2: But seeing that requires cutting through the densest most chaotic
Speaker 2: regions of space. I mean, galactic cores are totally obscured
Speaker 2: by incredibly thick toruses of dust and gas. You can't
Speaker 2: just use a normal optical telescope.
Speaker 3: Now, optical wavelengths are entirely useless there, it's just a
Speaker 3: wall of dust. That is where very long baseline interferometry
Speaker 3: or VLBI becomes essential, right, And.
Speaker 2: This is where the team led by Silk Britsen at
Speaker 2: the Max Plank Institute for the Radio Astronomy comes in.
Speaker 2: They bypass the optical problem entirely by relying on high
Speaker 2: frequency radio observations.
Speaker 3: Yeah, because radio waves can penetrate that circumnuclear dust chorus
Speaker 3: without scattering too much. It lets us actually resolve the
Speaker 3: immediate environment of the black hole itself.
Speaker 2: And they specifically focused on the relativistic jets. Mag five
Speaker 2: oh one is classified as a blazer.
Speaker 3: Right, yes, which means its primary jet is oriented at
Speaker 3: an extremely narrow angle relative to our line of sight.
Speaker 3: It's basically pointing right at.
Speaker 2: Us, like staring down the barrel of a cosmic.
Speaker 3: Flashlight exactly, and the relativistic beaming or Doppler boosting makes
Speaker 3: the jet appear exceptionally bright because the plasma is moving
Speaker 3: toward us at a huge fraction of the speed of light.
Speaker 2: Okay, so tell me about the actual mechanics of these jets.
Speaker 3: Well. The Blanford's Nedjeck process driving those jets is critical.
Speaker 3: Here the supermassive black hole is rotating right, and that
Speaker 3: rotation actually twists the space time around it in the
Speaker 3: ergosphere right, and that twisting winds up the magnetic field
Speaker 3: lines threading through the accretion disc. It creates this immense
Speaker 3: magnetic tension.
Speaker 2: Which just violently accelerates plasma outward along the rotational axis.
Speaker 3: Boom, you get a jet and for decades. The VLBI
Speaker 3: data for MICK five oh one showed this really powerful,
Speaker 3: highly variable single jet structure, which is standard for a blazer.
Speaker 2: But the max Plank team didn't just look at a
Speaker 2: single snapshot. They utilized a twenty three year archive of
Speaker 2: this VLBI data.
Speaker 3: A twenty three year stare. They weren't just looking for
Speaker 3: a high resolution picture, they were looking for kinematic evolution
Speaker 3: over more than two decades.
Speaker 2: It's like watching a time lapse of a creeping glacier
Speaker 2: only to suddenly realize decades later that there are actually
Speaker 2: two glaciers moving together.
Speaker 3: That's a perfect analogy because within that massive twenty three
Speaker 3: year data set they isolated the signature of a second,
Speaker 3: entirely distinct jet.
Speaker 2: But wait, space is full of interference and radiation. VLBI
Speaker 2: data on blazers is notoriously messy. How do astronomers distinguish
Speaker 2: an entirely new second jet from just a I don't know,
Speaker 2: a burp, a flare, or some distortion in the primary
Speaker 2: jet we already knew about it.
Speaker 3: That's the million dollar question, because a knot of plasma
Speaker 3: moving down the primary jet or some instability in the
Speaker 3: flow can easily mimic a secondary structure.
Speaker 2: So how do you prove it's a second black hole
Speaker 2: and not just a glitch in the single jet?
Speaker 3: Rigorous kinematic proof. You have to look for sustained non
Speaker 3: radial motion. A plasma shock or a flare within a
Speaker 3: single jet will propagate outward generally following the established flow
Speaker 3: of the jet.
Speaker 2: Even if it expands or dissipates, it still moves down
Speaker 2: the same path. Right.
Speaker 3: But what the team observed in Mystic five oh one
Speaker 3: over those twenty three years was a secondary structure that
Speaker 3: originated behind the primary core emission, and it exhibited a distinct,
Speaker 3: repeating counterclockwise motion around it.
Speaker 2: Oh wow, so it was orbiting.
Speaker 3: The motion is the smoking gun. A localized instability does
Speaker 3: not establish a sustained orbital trajectory around the primary core.
Speaker 2: So the only physical mechanism capable of generating a secondary
Speaker 2: tightly beamed outflow that is actively.
Speaker 3: Orbiting is a second super massive black hole, one that
Speaker 3: is actively a creating matter and powering its own independent jet.
Speaker 2: That is just mind blowing. And the realization that this
Speaker 2: second jet was moving like that, it opens up this
Speaker 2: wild new reality about the whole system. The entire galactic
Speaker 2: core of Markurrian five on one is in a state
Speaker 2: of chaotic motion. Yeah. The presence of the second jet
Speaker 2: also provides the framework for understanding the larger anomalies in
Speaker 2: the system. The entire primary jet structure exhibits this pronounced
Speaker 2: swaying motion.
Speaker 3: Silk Britsen compared evaluating the data to being on a
Speaker 3: moving ship. The entire system is precessing.
Speaker 2: Yes, the orbital plane of the binary is essentially wobbling.
Speaker 3: Because if you have two super massive bodies in a
Speaker 3: tight orbit, their individual spins and their orbital angular momentum
Speaker 3: are constantly interacting.
Speaker 2: Frame dragging, the lens thiring effect becomes incredibly pronounced at
Speaker 2: these masses in proximity. The rotating masses literally drag the
Speaker 2: local fabric of space time along with.
Speaker 3: Them, twisting the orientation of the accretion disks and the
Speaker 3: jets they produce.
Speaker 2: Exactly, so the angle of those jets relative to Earth
Speaker 2: is in a state of continuous predictable change. The sweeping
Speaker 2: motion alters the beaming effects.
Speaker 3: We observe, and this wobbling, this processing geometry, is what
Speaker 3: ultimately led to that massive event in June of twenty
Speaker 3: twenty two, the Einstein ring.
Speaker 2: Yes, gravitational lensing in action. Break that down for me,
Speaker 2: because the physics gravitational lensing are just wild. It happens
Speaker 2: when a massive four ground object warps the space time
Speaker 2: around it, bending the pass of light from a background
Speaker 2: source right right.
Speaker 3: But the specific alignment required to produce a complete ring
Speaker 3: rather than just an arc or multiple blurry images, requires
Speaker 3: an almost mathematically perfect sizogy.
Speaker 2: A perfect alignment between the observer us, the lens and.
Speaker 3: The source precisely. It relies on the impact parameter and
Speaker 3: the specific orientation. So in June twenty twenty two, the
Speaker 3: precession of the binary system brought the primary more massive
Speaker 3: black hole directly across our line of sight to the
Speaker 3: base of the secondary jet.
Speaker 2: Wow. So the primary black hole acted as the gravitational
Speaker 2: lens for the second black hole's jet.
Speaker 3: Yes, Because the alignment was so precise, the radio emissions
Speaker 3: from the secondary jet passing through the primari's gravitational well
Speaker 3: were deflected equally in all directs.
Speaker 2: It's like looking at a candle flame through the thick
Speaker 2: base of a wineglass. The glass bends the light into
Speaker 2: a complete circle. But here the wineglass is a supermassive
Speaker 2: black hole.
Speaker 3: That's exactly what it looks like. The warped space time
Speaker 3: stretched that emission into a perfect closed circular contour around
Speaker 3: the primary black hole's position, a tangential caustic Well.
Speaker 2: Let me ask you this, does this kind of perfect
Speaker 2: ring forming alignment happen on a regular schedule due to
Speaker 2: the orbit or was June twenty twenty two just a
Speaker 2: moment of incredibly lucky cosmic timing for us?
Speaker 3: Well, because of the procession, it is a transient alignment,
Speaker 3: so catching it in a twenty three year window is
Speaker 3: an incredibly rare observational triumph. It's a huge stroke of luck,
Speaker 3: but it's also a testament to just continuously watching the
Speaker 3: system and.
Speaker 2: Catching that ring wasn't just for a cool picture, right,
Speaker 2: It provided direct geometric conformation of the mass distribution and
Speaker 2: the separation of the two black.
Speaker 3: Holes exactly the radius of the Einstein ring. The Einstein
Speaker 3: radius is direct proportional to the square root of the
Speaker 3: mass of the lensing object.
Speaker 2: So by measuring the angular size of the ring and
Speaker 2: combining it with the data from the twenty three year
Speaker 2: VLBI study, they could finally lock down the orbital parameters
Speaker 2: of the binary.
Speaker 3: With unprecedented precision, and the numbers they derived are just staggering.
Speaker 2: Let's get into those numbers the final countdown, because the
Speaker 2: orbital period they calculated is just one hundred and twenty
Speaker 2: one days.
Speaker 3: Which is incredibly fast, and the physical separation between the
Speaker 3: two supermassive black holes is calculated to be between two
Speaker 3: hundred and fifty and five hundred and forty astronomical units.
Speaker 2: Wait, two hundred and fifty to five hundred and forty AU.
Speaker 2: I mean that sounds like a big number, but for
Speaker 2: objects weighing hundreds of millions or billions of solar masses,
Speaker 2: that is terrifyingly close.
Speaker 3: It places them deep into the strongly relativistic regime. I mean,
Speaker 3: the actual physical size of the black holes, their schwartz
Speaker 3: Child radioccupy significant fraction of that space.
Speaker 2: For scale two hundred and fifty AU is roughly six
Speaker 2: times the distance from our Sun to Pluto.
Speaker 3: Yeah, that's practical. Touching in galactic.
Speaker 2: Terms, in one hundred and twenty one days is basically
Speaker 2: a semester of college, and these billion sun mass objects
Speaker 2: are completing a full lap in that time. The gravitational
Speaker 2: forces at play are unimaginable.
Speaker 3: For objects of this mass to complete an entire orbital
Speaker 3: circuit in just four months, they have to be moving
Speaker 3: at a significant fraction of the speed of light.
Speaker 2: The sheer kinetic energy driving that one hundred and twenty
Speaker 2: one day orbit dictates an incredibly aggressive rate of orbital decay, doesn't.
Speaker 3: It It does. The system is governed by Peter's equations
Speaker 3: for gravitational radiation. Now it's shedding massive amounts of orbital
Speaker 3: energy and angular momentum by radiating low frequency gravitational waves, and.
Speaker 2: The decay rate accelerates exponentially as they draw closer.
Speaker 3: Right, the power radio by gravitational waves is inversely proportional
Speaker 3: to the fifth power of the orbital separation, so the
Speaker 3: closer they get, the faster they fall.
Speaker 2: In, which brings us to the timeline because the calculations
Speaker 2: placed the final coalescence of these two behemoths within approximately
Speaker 2: one hundred.
Speaker 3: Years, just one hundred years. We are not looking at
Speaker 3: a merger on some vague cosmological time scale. We are
Speaker 3: looking at an event that will occur within a human generational.
Speaker 2: Timeframe god'smc microsecond.
Speaker 3: Exactly, and the steepness of that inspiral curve over the
Speaker 3: next century is going to be profound. The orbit will
Speaker 3: continue to shrink, the period will drop from one hundred
Speaker 3: and twenty one days down to weeks, then.
Speaker 2: Days, until the event horizons finally intersect and just ring
Speaker 2: down into a single newly formed black hole. Okay, So
Speaker 2: if they are that close and moving that fast and
Speaker 2: give an emerge one hundred years, why can't we just
Speaker 2: point to the biggest telescope we have at hercules and
Speaker 2: watch them crash.
Speaker 3: And that is the ultimate frustration of observational astrophysics. Right there,
Speaker 3: the system is four hundred and fifty six million light
Speaker 3: years away. Right at that distance, an orbital separation of
Speaker 3: two fifty to five hundred and forty au translates to
Speaker 3: an angular resolution requirement on the order of microorc seconds,
Speaker 3: which is too small way too small. Even the event
Speaker 3: horizon telescope, which famously imaged black holes in twenty nineteen.
Speaker 3: In twenty twenty two, it operates in the tens of
Speaker 3: micro arc.
Speaker 2: Seconds, so it's just a hard physical wall.
Speaker 3: The physical Railey criterion prevents us from ever optically or
Speaker 3: radiometrically resolving the two distinct event horizons right before impact.
Speaker 2: So the actual physical merger will remain visually unresolved. A
Speaker 2: single point of intense radio and X ray emission is
Speaker 2: all our telescopes are ever going to capture.
Speaker 3: Yeah, but that inability to see them as two separate
Speaker 3: objects is precisely why Murk five oh one is fundamentally
Speaker 3: shifting our observational paradigm. We are moving toward continuous gravitational wave.
Speaker 2: Astronomy invisible ripples. We essentially have to trade our eyes
Speaker 2: for our ears.
Speaker 3: That's exactly what we have.
Speaker 2: To do, because we won't be able to see the
Speaker 2: splash of the collision, but we will absolutely feel the
Speaker 2: ripples hitting the shore.
Speaker 3: Right, we have to move past the electromagnetic spectrum entirely. Now.
Speaker 3: Ligo and Virgo have revolutionized astrophysics by detecting high frequency
Speaker 3: gravitational waves from stellar mass black holes.
Speaker 2: But a supermassive binary on one hundred and twenty one
Speaker 2: day orbit operates at a vastly different frequency right.
Speaker 3: A completely different scale. The wave frequency is basically twice
Speaker 3: the orbital frequency. So for a one hundred and twenty
Speaker 3: one day orbit, we're dealing with gravitational waves in the
Speaker 3: Nanohurtz regime.
Speaker 2: Meaning the physical wavelengths of these gravity ripples span light years.
Speaker 3: Yes, ground based interferometers like Lego are entirely blind to
Speaker 3: these frequencies. To detect nanohertz gravitational waves, you need a
Speaker 3: detector baseline on a galactic scale.
Speaker 2: Which sounds like science fiction, but we actually have one
Speaker 2: pulsar timing arrays.
Speaker 3: The European Pulsar Timing Array NANOGrav and the Park's array explain.
Speaker 2: How a pulsar timing array actually works as a detector.
Speaker 2: How do scientists use the steady ticking of dead stars
Speaker 2: to feel gravity warping.
Speaker 3: It's brilliant, really. The methodology relies on millisecond pulsars. These
Speaker 3: are ultra dense neutron stars that have been spun up
Speaker 3: by a creating material from a companion.
Speaker 2: Star, so they spin incredibly fast.
Speaker 3: Rotational periods on the order of milliseconds, and because they
Speaker 3: have this immense moment of inertia, their rotation is incredibly stable.
Speaker 3: They function as highly precise celestial clocks, and.
Speaker 2: We can model their radio pulses down to the nanosecond exactly.
Speaker 3: We account for incredibly complex variables, including the interstellar medium
Speaker 3: and the proper motion of the pulsars themselves. We know
Speaker 3: exactly when a pulse should hit our telescopes on Earth.
Speaker 2: So what happens when a nanohurtz gravitational wave rolls through.
Speaker 3: It repropagates through the local space time between Earth and
Speaker 3: that monitored millisecond pulsar. It physically perturbs the space time metric.
Speaker 3: It alters the geodesic path the radiopulse has to travel.
Speaker 2: It stretches and squeezes the space itself.
Speaker 3: Yes, the wave induces a quadrupolar distortion in space time.
Speaker 3: As the space between Earth and the pulsar is stretched,
Speaker 3: the radiopulse takes a slightly longer proper time to arrive, so.
Speaker 2: It arrives slightly late, a positive timing residual.
Speaker 3: Right, and as the space is compressed the pulse path shortens,
Speaker 3: it creates a negative timing residual it arrives early.
Speaker 2: Wow. Wow. So by monitoring dozens of these millisecond pulsars
Speaker 2: distributed all across the sky, astronomers look for a very
Speaker 2: specific pattern in these early and late arrivals.
Speaker 3: The hellings Down spatial correlation. It's a specific geometric signature
Speaker 3: in those timing residuals that can only be produced by
Speaker 3: a passing gravitational wave.
Speaker 2: And in twenty twenty three, these array collaborations actually found
Speaker 2: evidence of a gravitational wave background, right yeah, like a
Speaker 2: universal hum caused by supermassive binaries everywhere.
Speaker 3: They did, But up until now they've only been focused
Speaker 3: on that stochastic background, that general hum. Mech five oh
Speaker 3: one changes that focus.
Speaker 2: Entirely because MIKE five oh one is the perfect candidate
Speaker 2: to link specific waves to a specific.
Speaker 3: Binary exactly because the orbital parameters are now known, we
Speaker 3: know the one hundred and twenty one day period, and
Speaker 3: we have one hundred year countdown. We know exactly what
Speaker 3: frequency to look for and how that frequency is going
Speaker 3: to evolve.
Speaker 2: Because as the orbit shrinks, the velocity increases and the
Speaker 2: frequency of the emitted gravitational waves shifts upward.
Speaker 3: Right, the chirp. Mass of the system dictates the rate
Speaker 3: of this frequency evolution, and over the next few decades,
Speaker 3: milliar five oh one will move dynamically right through the
Speaker 3: sensitivity band of our pulsar timing arrays.
Speaker 2: So, as co author Hector Olivari is noted, we might
Speaker 2: soon see the frequency of these timing residuals steadily rise.
Speaker 2: We are getting a front row seat to the merger.
Speaker 3: It provides a real time, continuous track of the final inspiral.
Speaker 3: The gravitational wave data will let us measure the mass ratio,
Speaker 3: the spin alignments, and the orbital eccentricity with a precision
Speaker 3: that optical telescopes could just never achieve. At four hundred
Speaker 3: and fifty six million light years.
Speaker 2: It really is a masterclass in modern astrophysics, just the
Speaker 2: entire progression of this discovery.
Speaker 3: It really is.
Speaker 2: I mean, you start with the theoretical imperative, the idea
Speaker 2: that supermassive black holes must grow through hierarchical merging to
Speaker 2: overcome the final parsec problem.
Speaker 3: Right, the math said it had to be happening.
Speaker 2: Which leads to the grueling twenty three year VLBI campaign
Speaker 2: just staring at the radio frequencies until they ice late
Speaker 2: the kinematic signature of a precessing secondary jet in marcirion
Speaker 2: five to OHO one.
Speaker 3: And then the precession of that system yields the June
Speaker 3: twenty twenty two Einstein Ring, that lucky moment of perfect
Speaker 3: gravitational lensing that locked in the orbital parameters.
Speaker 2: Revealing one hundred and twenty one day orbit, a separation
Speaker 2: measured in mere hundreds of astronomical units, and a one
Speaker 2: hundred year countdown to an impact that will generate a
Speaker 2: massive spike in nanohurtz gravitational waves.
Speaker 3: It's all connected the tracking of those raves via the
Speaker 3: shifting paths of millisecond pulsars. It represents the absolute cutting
Speaker 3: edge of multi messenger astronomy.
Speaker 2: From identifying a system through the relativistic beaming of its
Speaker 2: plasma jets to calculating its ultimate demise through the measurement
Speaker 2: of space time strain. It's an incredible evolution of our capabilities.
Speaker 3: It really shows how astronomical progress relies on shifting our perspective.
Speaker 3: When looking at light is no longer enough, human ingenuity
Speaker 3: figures out how to measure the ripples of gravity itself.
Speaker 2: I want to leave you the listener with one fire
Speaker 2: kind of haunting realization. To mull Over, We've talked a
Speaker 2: lot about the one hundred year countdown, but think about
Speaker 2: what the vast distance to Marcaryan fible one actually means
Speaker 2: in the context of this timeline. Right, the speed of
Speaker 2: light exactly the radio frequencies that the max Plank team
Speaker 2: analyzed the photons that were warped into the Einstein Ring
Speaker 2: in twenty twenty two, They have been traveling across the
Speaker 2: intergalactic medium for four hundred and fifty six million years.
Speaker 3: Because electromagnetic radiation and gravitational waves both propagate at the
Speaker 3: same fundamental speed limit, the speed of causality in a vacuum.
Speaker 2: So this one hundred year countdown to the merger, it
Speaker 2: is based entirely on the state of the system four
Speaker 2: hundred and fifty six million years ago.
Speaker 3: Yeah, it's a snapshot from the deep past.
Speaker 2: Meeting the inspiral, the final coalescence, the massive ring down
Speaker 2: of the newly formed hypermassive black hole. All of those
Speaker 2: violent events actually occurred during the Ordovision period.
Speaker 3: Here on Earth, hundreds of millions of years before the
Speaker 3: first dinosaurs even appeared.
Speaker 2: The cataclysm has already happened. The colossal gravitational shockwave from
Speaker 2: their final impact has been expanding outward through the universe
Speaker 2: ever since. It has already silently torn through the dark void,
Speaker 2: washed over countless star systems and unknown worlds in the
Speaker 2: intervening space.
Speaker 3: We aren't predicting the future at all.
Speaker 2: No, we are simply waiting for the violent geometry of
Speaker 2: that ancient collision to finally wash over our arrays. Until
Speaker 2: next time, keep looking up.