WEBVTT

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<v Speaker 1>Welcome to Bedtime Astronomy. Explore the wonders of the cosmos

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<v Speaker 1>with our soothing Bedtime Astronomie podcast. Each episode offers a

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<v Speaker 1>gentle journey through the stars, planets, and beyond, perfect for

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<v Speaker 1>unwinding after a long day. Let's travel through the mysteries

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<v Speaker 1>of the universe as you drift off into a peaceful

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<v Speaker 1>slumber under the night sky.

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<v Speaker 2>I want you to just close your eyes for a second. Well,

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<v Speaker 2>assuming you aren't driving or operating heavy machinery, right.

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<v Speaker 3>Yeah, please keep your eyes open if you're behind the.

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<v Speaker 2>Wheel exactly, but if you can, I want you to

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<v Speaker 2>imagine that you are standing at the exact center of

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<v Speaker 2>our galaxy, the Milky Way.

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<v Speaker 3>Which is an incredibly hostile place to imagine yourself.

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<v Speaker 2>By the way, Oh, it's terrifying. You aren't looking up

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<v Speaker 2>at some peaceful, twinkling night sky from a quiet suburban

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<v Speaker 2>backyard in the Orion spur right, not at all. You

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<v Speaker 2>are completely surrounded by an environment so dense and like,

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<v Speaker 2>so utterly chaotic and violently dynamic that it practically defies

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<v Speaker 2>human comprehension.

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<v Speaker 3>It really is like a cosmic mosh pit out there.

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<v Speaker 2>That's the perfect way to describe it. You've got millions

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<v Speaker 2>of massive stars packed into a volume of space where

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<v Speaker 2>you know, we might only see one or two stars

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<v Speaker 2>around our own sun.

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<v Speaker 3>And if you had eyes that could see across the

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<v Speaker 3>entire electromagnetic spectrum, the radiation would just be absolutely blinding.

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<v Speaker 2>Right, and the gravitational forces are pulling, twisting, and warping

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<v Speaker 2>literally everything in sight. And right there, anchoring this entire

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<v Speaker 2>terrifyingly beautiful merry go round is Sagittarius.

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<v Speaker 3>A, our residence super massive black hole.

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<v Speaker 2>Yeah, the one packing the mass of four million of

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<v Speaker 2>our suns into a space that I think could easily

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<v Speaker 2>fit inside the orbit of Mercury right roughly.

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<v Speaker 3>Yes, it really is the ultimate extreme environment.

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<v Speaker 2>It's wild.

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<v Speaker 3>It is because it is so easy for us down

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<v Speaker 3>here on Earth to think of a black hole as

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<v Speaker 3>just you know, a dark, empty void sitting in the

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<v Speaker 3>middle of nowhere, ye leave, vacuuming things.

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<v Speaker 2>Up like a giant's space stream, exactly like a drain.

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<v Speaker 3>Yeah. But the reality of Sagittarius A, or sgr A

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<v Speaker 3>as we usually call it, is that the area immediately

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<v Speaker 3>surrounding it is anything but empty. It is essentially a

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<v Speaker 3>natural laboratory for us It lets us witness first hand

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<v Speaker 3>exactly how matter behaves when it's pushed to the absolute

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<v Speaker 3>limits of physics.

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<v Speaker 2>Right on the doorstep of this thing, Right on.

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<v Speaker 3>The doorstep where the gravity is so intense that not

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<v Speaker 3>even light can escape once it crosses that event horizon,

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<v Speaker 3>we are watching extreme physics play out in real time.

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<v Speaker 2>Okay, let's unpack this because for the last twenty years

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<v Speaker 2>or so, astronomers have been staring into this specific natural laboratory,

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<v Speaker 2>peering through all the dust and the glare, and they've.

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<v Speaker 3>Been completely baffled by a mystery.

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<v Speaker 2>A cosmic who do nit? Basically because they have been

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<v Speaker 2>watching these very mysterious, highly compact clouds of glowing gas

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<v Speaker 2>that are actively circling and feeding the super massive black hole.

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<v Speaker 3>Right, little glowing gas clouds.

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<v Speaker 2>Nobody knew where they came from. They were just out

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<v Speaker 2>there braving the extreme gravity, acting like these perfectly timed

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<v Speaker 2>appetizers for the black hole.

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<v Speaker 3>It's a remarkable detective story, honestly.

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<v Speaker 2>It really is. And today we are going to trace

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<v Speaker 2>the exact origin of these enigmatic gas clouds. We're going

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<v Speaker 2>back to the scene of the crime to understand the

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<v Speaker 2>incredible stellar mechanics that are cooking up these celestial meals.

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<v Speaker 3>And the challenge here is just monumental because you know,

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<v Speaker 3>if you are trying to observe the galactic center from Earth,

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<v Speaker 3>you were looking through twenty six thousand light years of

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<v Speaker 3>interstellar dust.

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<v Speaker 2>Twenty six thousand light years.

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<v Speaker 3>Yeah, dust, debris, intervening gas. Yeah, You're not just pointing

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<v Speaker 3>a backyard telescope at the sky and snapping a clear

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<v Speaker 3>photograph of what's happening.

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<v Speaker 2>Right, You're looking through basically a galactic fog.

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<v Speaker 3>A very thick fog. The clues are heavily obscured, the

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<v Speaker 3>environment itself is incredibly hostile, and the objects we are

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<v Speaker 3>tracking are well on a cosmic scale, vanishingly.

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<v Speaker 2>Small, elusive little things.

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<v Speaker 3>Very elusive. To actually figure out where these specific clouds

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<v Speaker 3>of gas originated, you have to peel back multiple layers

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<v Speaker 3>of complex astrophysics.

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<v Speaker 2>And use some crazy advanced technology, which we'll get into. Well,

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<v Speaker 2>let's start with the victims, or maybe of the suspects,

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<v Speaker 2>depending on how you look at the crime scene, the

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<v Speaker 2>g cloud family, the G cloud family. Now, looking back

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<v Speaker 2>at the records, astronomers had noticed anomalies in the center

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<v Speaker 2>of the galaxy for a while but things really kicked

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<v Speaker 2>off with a major discovery back in twenty twelve.

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<v Speaker 3>Right, that's right, Using some seriously advanced infrared observations teams

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<v Speaker 3>spotted these compact gas clouds hanging out uncomfortably close to SGRA.

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<v Speaker 2>Uncomfortably close is a good way to put it. And

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<v Speaker 2>the most famous one, the one that really made the

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<v Speaker 2>mainstream scientific headlines back then, is called G two, Yes,

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<v Speaker 2>G two, And to give you the listener a sense

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<v Speaker 2>of what we are actually dealing with here, G two

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<v Speaker 2>isn't like the size of a star. It contains roughly

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<v Speaker 2>the mass of three earths, which.

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<v Speaker 3>Is tiny for an astronomical.

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<v Speaker 2>Object, minuscule, and the data shows it emits this very

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<v Speaker 2>specific light signature from hydrogen and helium, which tells us

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<v Speaker 2>we're dealing with a hot, dusty cloud of gas, not

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<v Speaker 2>a solid, rocky planet.

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<v Speaker 3>Right. And what's fascinating here is that G two is

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<v Speaker 3>not just a random, formless fog drifting aimlessly through space like.

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<v Speaker 2>You'd normally picture a gas cloud.

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<v Speaker 3>Exactly when we picture gas in space, we usually think

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<v Speaker 3>of a nebula of vast diffuse, very static, but G

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<v Speaker 3>two is a highly cohesive, trackable entity. It behaves almost

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<v Speaker 3>like a solid body in terms of its orders a path,

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<v Speaker 3>and that path is incredibly elongated or eccentric.

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<v Speaker 2>So it's not a nice, clean circle.

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<v Speaker 3>Far from it. It moves through this extreme gravitational field,

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<v Speaker 3>accelerating to thousands of kilometers per second as it swings

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<v Speaker 3>near the black hole. Wow, it acts almost like a

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<v Speaker 3>glowing tracer dye dropped into a rushing river. By watching

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<v Speaker 3>how G two moves and how its shape stretches over time,

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<v Speaker 3>astronomers can map the invisible gravitational.

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<v Speaker 2>Currents swirling around the supermassive black hole. That is so cool.

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<v Speaker 2>But wait, surviving near a black hole isn't a exactly

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<v Speaker 2>a walk in the park, not at all. And this

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<v Speaker 2>is the part of the data that really made me

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<v Speaker 2>do a double take. How does a cloud of gas

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<v Speaker 2>which is just loosely associated atoms right.

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<v Speaker 3>Essentially yes, held together by extremely weak gravity?

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<v Speaker 2>Right? So how does it maintain any sort of compact

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<v Speaker 2>shape when it's subjected to the monumental tidal forces of

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<v Speaker 2>a super massive black hole.

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<v Speaker 3>It's a great question.

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<v Speaker 2>Shouldn't the black hole's gravity just, I don't know, shred

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<v Speaker 2>it instantly the moment it gets close.

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<v Speaker 3>Well, that survival mechanism was the central puzzle for years

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<v Speaker 3>following the twenty twelve discovery because the tidal forces near

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<v Speaker 3>SGRA are just beyond immense.

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<v Speaker 2>You can't even imagine.

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<v Speaker 3>To conceptualize this, imagine you are falling feet first toward

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<v Speaker 3>a black hole.

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<v Speaker 2>Okay, slightly terrifying, but I'm with you.

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<v Speaker 3>The gravity pulling on your feet is significantly stronger than

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<v Speaker 3>the gravity pulling on your head, simply because your feet

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<v Speaker 3>are physically closer to the center of mass.

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<v Speaker 2>Right, makes sense.

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<v Speaker 3>So that difference in gravitational pull that gradient. It stretches

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<v Speaker 3>you out vertically while simultaneously compressing you horses wou. In astrophysics,

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<v Speaker 3>we literally call this process spaghetification.

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<v Speaker 2>I always love that term. I mean, it sounds like

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<v Speaker 2>something out of a cartoon, but it really describes one

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<v Speaker 2>of the most terrifying ways to be destroyed in the universe.

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<v Speaker 3>It is a brilliantly descriptive term. Now apply that same

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<v Speaker 3>mechanical stretching to a relatively small cloud of gas like

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<v Speaker 3>G two.

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<v Speaker 2>Okay, so it's getting spaghettified exactly. Yeah.

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<v Speaker 3>As G two plunges into the deepest part of the gravity, well,

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<v Speaker 3>the front of the cloud is being pulled significantly faster

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<v Speaker 3>than the back of the cloud. Right, according to classical physics,

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<v Speaker 3>it should smear out entirely into a long, thin, invisible

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<v Speaker 3>wisp of atoms. It should lose all its structure, but

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<v Speaker 3>it doesn't. Well, it does stretch. Observations show it has

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<v Speaker 3>this faint, elongated trailing tail that astronomers creatively named G

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<v Speaker 3>two t.

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<v Speaker 2>Ah G two tail. Very creative, right, But the.

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<v Speaker 3>Core of the cloud itself has remained surprisingly stubbornly compact.

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<v Speaker 3>It is held together and remained visible much longer than

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<v Speaker 3>a simple puff of gas should.

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<v Speaker 2>That is so weird. And the very fact that we

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<v Speaker 2>see the bright emission lines of hydrogen and helium means

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<v Speaker 2>this gas is hot, right.

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<v Speaker 3>Extremely hot. It is being energized and ionized by the

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<v Speaker 3>intense ambient radiation of the environ which.

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<v Speaker 2>Is why it glows so brightly in the infrared spectrum

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<v Speaker 2>even as it's getting stretched out.

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<v Speaker 3>Exactly.

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<v Speaker 2>Okay, So if I'm picturing this right, it's like a

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<v Speaker 2>cosmic comet, but instead of a solid rock made of

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<v Speaker 2>ice and dirt, it's a blob made entirely of glowing

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<v Speaker 2>hot dust and gas.

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<v Speaker 3>Yes, a very hot blob, just.

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<v Speaker 2>Dragging this faint tail G two t behind it as

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<v Speaker 2>it races at blinding speeds around this massive gravitational sinkhole.

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<v Speaker 3>That's a perfect visual in Just when people.

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<v Speaker 2>Were scratching their heads over G two trying to figure

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<v Speaker 2>out how it was surviving spaghettification, some researchers went back

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<v Speaker 2>in mind the old archival.

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<v Speaker 3>Data, which is often where the best discoveries hide, truly,

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<v Speaker 3>and what they found completely shifted the paradigm.

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<v Speaker 2>G two wasn't a lone wolf.

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<v Speaker 3>No, it wasn't king In the.

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<v Speaker 2>Data from years prior, they found an earlier, nearly identical cloud.

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<v Speaker 2>They retroactively named it G one, and it was traveling

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<v Speaker 2>on a strikingly similar orbit just further ahead.

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<v Speaker 3>Finding G one was the absolute turning point in this investigation.

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<v Speaker 2>Really, why is that so crucial?

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<v Speaker 3>Because the moment you find multiple distinct objects on nearly

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<v Speaker 3>identical trajectories in astronomy, you have to stop thinking about

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<v Speaker 3>them as isolated anomalies. Oh, I see a single cloud

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<v Speaker 3>of gas surviving near a black hole. Could just be

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<v Speaker 3>a fluke, maybe a star that had its outer layer

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<v Speaker 3>script or a random collision.

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<v Speaker 2>Just a weird coincidence.

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<v Speaker 3>Right, But two distinct clouds plus a trailing tail, all

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<v Speaker 3>following the exact same, highly eccentric path through the single

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<v Speaker 3>most chaotic environment in the galaxy. That's a pattern exactly.

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<v Speaker 3>It implies a much larger system. It strongly implies a

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<v Speaker 3>shared origin or an ongoing mechanism actively producing these objects

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<v Speaker 3>in a.

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<v Speaker 2>Sequence, which brings us to the underlying structure connecting them all.

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<v Speaker 2>Because it became clear that these aren't just isolated clumps

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<v Speaker 2>of gas floating independently in the dark.

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<v Speaker 3>The plot thickens significantly here.

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<v Speaker 2>It really does, because recently observers noticed that gas from

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<v Speaker 2>G two's tail that stretched out G two T section

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<v Speaker 2>has actually condensed into a third distinct clump.

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<v Speaker 3>Yes, another clump formed.

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<v Speaker 2>Now, if you are a logical person, you'd assume the

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<v Speaker 2>astronomical community would name this new clump G three. You

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<v Speaker 2>would think so, But no, when you dig into the literature,

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<v Speaker 2>you find out they had already used the name G

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<v Speaker 2>three for an entirely different, unrelated object somewhere else in

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<v Speaker 2>the galactic center.

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<v Speaker 3>Yeah, astronomical naming conventions can be a bit of a nightmare.

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<v Speaker 2>It's a whole separate mystery. We've got telescopes literally called

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<v Speaker 2>the extremely large telescope, and then we have overlapping designations

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<v Speaker 2>for gas clouds. We do our best, so for the

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<v Speaker 2>sake of clarity, we'll just refer to it as the

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<v Speaker 2>third clump. But naming aside. The realization here is profound

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<v Speaker 2>G one, G two, and this third clump they form.

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<v Speaker 3>A streamer one one two three streamer.

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<v Speaker 2>Right. It's not a set of distinct pearl like clouds

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<v Speaker 2>on a string. It's a coherent, continuous flowing river of

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<v Speaker 2>material moving straight through the heart of the galactic center.

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<v Speaker 3>And that shift from viewing these as individual objects to

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<v Speaker 3>viewing them as a continuous streamer fundamentally changes how we

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<v Speaker 3>model the physics of the region. How So well, when

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<v Speaker 3>we use words like clumps or clouds, we naturally picture discrete,

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<v Speaker 3>self contained objects, perhaps held together by their own internal gravity,

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<v Speaker 3>like giant gaseous asteroids.

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<v Speaker 2>Yeah, that's exactly what I was picturing, little floating blobs.

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<v Speaker 3>But the fluid dynamics of this newly identified streamer suggests

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<v Speaker 3>something entirely different. The gas in this massive cosmic river

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<v Speaker 3>isn't flowing at a uniform density, is highly turbulent. It

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<v Speaker 3>has natural fluctuations and instabilities as the river flows, sometimes

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<v Speaker 3>the gas compresses slightly, pushing the atoms closer together.

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<v Speaker 2>And sometimes it thins out, I guess.

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<v Speaker 3>Exactly, into wider or less dense streams. And the reason

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<v Speaker 3>we see these distinct visual clumps like G one and

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<v Speaker 3>G two while the rest of the river remains largely invisible.

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<v Speaker 2>To it, right, the rest of it is invisible.

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<v Speaker 3>Mostly yes, And it comes down entirely to the specific

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<v Speaker 3>physics of how ionized gas emits light in these extreme conditions.

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<v Speaker 2>Ah okay, I want to dig into that physics because

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<v Speaker 2>it clears up a massive misconception. The brightness of these clouds,

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<v Speaker 2>the infrared light they shoot at our telescopes. It doesn't

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<v Speaker 2>increase on a linear scale, right, No, it doesn't. The

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<v Speaker 2>physics dictates that the brightness increases with the square of

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<v Speaker 2>their density. So if the density of a patch of

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<v Speaker 2>gas doubles, it doesn't get twice as bright. It gets

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<v Speaker 2>four times as bright.

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<v Speaker 3>That's right.

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<v Speaker 2>It scales with the square, and if it triples, it

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<v Speaker 2>gets nine times as bright. So let me make sure

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<v Speaker 2>I'm wrapping my head around this. It's not actually a

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<v Speaker 2>string of separate solid pearls floating in space at all.

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<v Speaker 2>At all, it is literally just one continuous river. But

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<v Speaker 2>because of that squared relationship, the areas where the gas

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<v Speaker 2>compresses even just a little bit, like rapids and terrestrial

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<v Speaker 2>river suddenly light up like a neon sign.

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<v Speaker 3>That is a fantastic way to conceptualize it. The rapids

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<v Speaker 3>analogy perfectly captures the fluid dynamics happening on a cosmic scale.

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<v Speaker 3>Here we are dealing with continuous flowing matter. When the

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<v Speaker 3>gas in this stream compresses, maybe due to internal turbulence

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<v Speaker 3>or subtle gravitational interactions along its path, the density spikes,

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<v Speaker 3>the local density spikes, and because the emission brightness scales

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<v Speaker 3>with the square of the density, a section of the

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<v Speaker 3>river that is just moderately denser than the surrounding flow

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<v Speaker 3>suddenly crosses a visibility threshold.

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<v Speaker 2>So it just pops out of the darkness exactly.

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<v Speaker 3>It becomes vastly brighter, illuminating that specific compressed knot of

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<v Speaker 3>gas against the pitch black background of empty space.

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<v Speaker 2>That is wild.

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<v Speaker 3>It's largely an optical effect driven by the thermodynamics of

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<v Speaker 3>the emission process. So what astronomers have been calling the

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<v Speaker 3>distinct g clouds for.

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<v Speaker 2>The last decade are really just the rapids.

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<v Speaker 3>Yes, just the most compressed, highly illuminated rapids in a

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<v Speaker 3>continuous flowing river of gas that is steadily winding its

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<v Speaker 3>way towards SAGITTARIUSA.

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<v Speaker 2>Okay, so we have this picture now, a glowing, clumpy

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<v Speaker 2>river of hot plasma flowing relentlessly toward the supermassive black hole.

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<v Speaker 3>A majestic, terrifying river truly.

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<v Speaker 2>But the obvious question, if you are looking at the

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<v Speaker 2>ecosystem of the galaxy is what does this river actually

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<v Speaker 2>do to the black hole itself? It feeds it, right,

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<v Speaker 2>because black holes aren't just static sinkholes. They have to eat.

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<v Speaker 2>They sustain their immense mass by accreting matter, and right

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<v Speaker 2>here we have a literal river of matter flowing right

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<v Speaker 2>to its front door.

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<v Speaker 3>This river provides the fundamental fuel for the black hole's

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<v Speaker 3>current state. And what's critical to understand here isn't just

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<v Speaker 3>the existence of the fuel, but the specific volume and

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<v Speaker 3>rate of that delivery.

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<v Speaker 2>The portion sizes basically.

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<v Speaker 3>Exactly when the astrophysics teams ran the complex hydrodynamical calculations

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<v Speaker 3>on this G one two three streamer, they calculated the

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<v Speaker 3>mass of just one of these highly visible glowing clumps.

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<v Speaker 2>What did they find.

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<v Speaker 3>We are talking about roughly one earth mass of gaseous

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<v Speaker 3>material falling down toward the black Holes accretion zone every decade.

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<v Speaker 2>Let's put that in perspective, because here is where it

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<v Speaker 2>gets really mind bending. One Earth mass every ten years.

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<v Speaker 3>It sounds big to us, but.

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<v Speaker 2>Right in the cosmic scheme of things, an Earth mass

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<v Speaker 2>is practically nothing. The Sun alone is over three hundred

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<v Speaker 2>thousand times more massive than the Earth.

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<v Speaker 3>It's a tiny snack.

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<v Speaker 2>A microscopic snack. But imagine taking our entire planet, all

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<v Speaker 2>the oceans, the mountains, the core, mashing it down into

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<v Speaker 2>a giant, cohesive meat ball of hot gas, and dropping

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<v Speaker 2>it straight into a black hole once every decade, like clockwork.

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<v Speaker 3>It's a very specific dietary routine.

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<v Speaker 2>It's this highly precise, agonizingly slow droop feeding schedule. And

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<v Speaker 2>what's wild to me looking at the data is that

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<v Speaker 2>this relatively tiny intermittent meal is exactly what Sagittarius A

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<v Speaker 2>needs right now.

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<v Speaker 3>The precise matching of that supply to the black holes

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<v Speaker 3>demand is the key insight here. Sagittary's A is currently

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<v Speaker 3>what astrophysicists would classify as a remarkably quiet, almost starved,

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<v Speaker 3>supermassive black hole starved. Really, Yes, If you look deep

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<v Speaker 3>into the universe at other galaxies, you frequently see quasars.

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<v Speaker 3>These are super massive black holes that are actively consuming

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<v Speaker 3>colossal amounts of entire stars and massive gas clouds at

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<v Speaker 3>an incredible rate.

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<v Speaker 2>Just gorging themselves.

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<v Speaker 3>Gorging. They generate so much friction, heat, and radiation in

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<v Speaker 3>their accretion discs that the area immediately surrounding the black

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<v Speaker 3>hole can outshine all the billions of stars in their

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<v Speaker 3>host galaxy combined.

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00:16:33.279 --> 00:16:36.240
<v Speaker 2>That is horrifying. But our black hole isn't doing that.

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<v Speaker 3>No, our black hole is doing absolutely nothing of the sort.

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<v Speaker 3>It is in a low rumble, nearly dormant state.

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<v Speaker 2>Okay, so the earth size meatball every ten years, that.

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<v Speaker 3>Calculated dietary requirement of one Earth mass per decade derived

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00:16:48.320 --> 00:16:51.840
<v Speaker 3>from the g clouds perfectly aligns with the current incredibly

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<v Speaker 3>quiet energy output of.

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<v Speaker 2>SGRA, just enough to keep it ticking exactly.

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<v Speaker 3>It's just enough material crossing the event horizon and to

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<v Speaker 3>keep the engine simmering, maintaining its low level X ray

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00:17:03.480 --> 00:17:06.400
<v Speaker 3>and infrared flickering, but not nearly enough to ignite it

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<v Speaker 3>into a raging quasar.

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<v Speaker 2>So this little river of glowing gas isn't just some

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<v Speaker 2>random curiosity floating by. It is quite literally the primary

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<v Speaker 2>life support system keeping our galaxies central super massive black

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<v Speaker 2>hole actively ticking right now.

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<v Speaker 3>Yes. Furthermore, identifying this specific streamer solves a massive, long

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<v Speaker 3>standing mechanical problem in astrophysics regarding how black holes actually

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<v Speaker 3>feed in the first place.

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<v Speaker 2>Because they don't just suck everything up magically.

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<v Speaker 3>Right right. The general public often thinks of black holes

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<v Speaker 3>as cosmic vacuum cleaners that just possess an infinite inescapable suction,

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00:17:42.079 --> 00:17:45.240
<v Speaker 3>dragging in everything regardless of distance.

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00:17:45.000 --> 00:17:47.359
<v Speaker 2>Like a giant hoover in space exactly.

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00:17:48.319 --> 00:17:52.160
<v Speaker 3>But mechanically speaking, getting matter to actually fall into a

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00:17:52.200 --> 00:17:55.400
<v Speaker 3>black hole crossing the event horizon rather than just orbiting

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00:17:55.400 --> 00:17:58.559
<v Speaker 3>around it endlessly is incredibly.

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<v Speaker 2>Difficult because gravity is a two ways stream.

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<v Speaker 3>Gravity is a two way street, and orbital mechanics are stubborn.

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<v Speaker 2>Right. It's because of angular momentum. It's the exact same

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<v Speaker 2>reason the Earth just keeps spinning around the Sun year

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<v Speaker 2>after year instead of plunging into it. Precisely, we are

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<v Speaker 2>being pulled by the Sun's gravity, sure, but we are

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<v Speaker 2>moving too fast sideways that sideway's momentum keeps us locked

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<v Speaker 2>in a stable orbit. To fall in, we would have

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<v Speaker 2>to hit the brakes.

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<v Speaker 3>That sideways motion is the fundamental barrier to black hole feeding.

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<v Speaker 3>For matter to fall into the event horizon, it has

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<v Speaker 3>to lose a massive amount of that sideway's motion.

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<v Speaker 2>It have to shed its angular momentum.

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00:18:31.720 --> 00:18:36.000
<v Speaker 3>And dissipate its kinetic energy. Usually in a standard galactic model,

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<v Speaker 3>this happens via an accretion.

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00:18:37.920 --> 00:18:41.599
<v Speaker 2>Disc swirling disk of doom we always see in movies.

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<v Speaker 3>Right, gas and dust are drawn toward the black hole,

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<v Speaker 3>but because of their angular momentum, they settle into a massive,

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00:18:48.319 --> 00:18:53.759
<v Speaker 3>flattened swirling disc. Inside that disc, particles constantly rub against

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00:18:53.799 --> 00:18:56.119
<v Speaker 3>each other, creating immense.

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00:18:55.680 --> 00:18:57.519
<v Speaker 2>Friction, and friction creates heat.

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00:18:58.359 --> 00:19:01.720
<v Speaker 3>Exactly that friction generates heat, and in the process the

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00:19:01.799 --> 00:19:04.839
<v Speaker 3>matter loses energy. Only as its shed energy can it

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00:19:04.920 --> 00:19:07.319
<v Speaker 3>slowly gradually spiral inward.

388
00:19:07.079 --> 00:19:09.319
<v Speaker 2>Like circling a drain, very very slowly.

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00:19:09.480 --> 00:19:12.319
<v Speaker 3>This process can take millions of years from material at

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00:19:12.319 --> 00:19:14.480
<v Speaker 3>the outer edge of the disk to actually reach the center.

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00:19:15.039 --> 00:19:17.279
<v Speaker 3>But the geometry of the G one two three streamer

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00:19:17.559 --> 00:19:20.680
<v Speaker 3>acts as a direct high speed delivery system because it's.

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00:19:20.519 --> 00:19:23.599
<v Speaker 2>Not settling into a nice, polite circular disc. It's diving

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00:19:23.640 --> 00:19:25.079
<v Speaker 2>straight in exactly.

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00:19:25.759 --> 00:19:30.039
<v Speaker 3>The highly elongated plunging orbit of this specific gas river

396
00:19:30.680 --> 00:19:33.279
<v Speaker 3>means the material doesn't have to spend a million years

397
00:19:33.799 --> 00:19:36.680
<v Speaker 3>slowly spiraling through a crowded accretion disk. It gets to

398
00:19:36.680 --> 00:19:40.359
<v Speaker 3>ship the line. Yes, it is already on an extreme

399
00:19:40.400 --> 00:19:43.599
<v Speaker 3>trajectory that takes it incredibly close to the black hole

400
00:19:43.680 --> 00:19:46.119
<v Speaker 3>at its closest approach or periapsis.

401
00:19:46.400 --> 00:19:46.799
<v Speaker 2>Wow.

402
00:19:46.880 --> 00:19:50.039
<v Speaker 3>It dives in so steeply that it allows the extreme

403
00:19:50.119 --> 00:19:53.000
<v Speaker 3>tidal forces of the black hole to physically strip the

404
00:19:53.039 --> 00:19:56.279
<v Speaker 3>material away from the mainstream and feed it directly into

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00:19:56.279 --> 00:19:57.440
<v Speaker 3>the inner accretion zone.

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00:19:57.559 --> 00:20:01.279
<v Speaker 2>So understanding this specific, highly efficient fuel source is truly

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00:20:01.359 --> 00:20:05.119
<v Speaker 2>the golden ticket to understanding the current quiet state of

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00:20:05.160 --> 00:20:06.200
<v Speaker 2>our galaxy's heart.

409
00:20:06.319 --> 00:20:08.119
<v Speaker 3>It absolutely is Okay.

410
00:20:07.839 --> 00:20:10.160
<v Speaker 2>So we know the meal. It's this clumpy river of

411
00:20:10.200 --> 00:20:14.480
<v Speaker 2>glowing hydrogen and helium, and we know exactly who's eating it. Sagittarius,

412
00:20:14.480 --> 00:20:18.039
<v Speaker 2>a quietly munching on an earth sized gaseous snack every

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00:20:18.119 --> 00:20:20.359
<v Speaker 2>decade just to keep the lights on, right, But who

414
00:20:20.519 --> 00:20:23.400
<v Speaker 2>is cooking the meal? Where did this massive, perfectly timed

415
00:20:23.519 --> 00:20:26.400
<v Speaker 2>river of gas actually come from the first place? That

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00:20:26.559 --> 00:20:30.039
<v Speaker 2>is the ultimate question, because as we've established, gas in

417
00:20:30.079 --> 00:20:33.839
<v Speaker 2>the galactic center gets shredded. You don't just get a continuous,

418
00:20:34.000 --> 00:20:37.680
<v Speaker 2>highly structured river of hot gas materializing out of nowhere.

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00:20:37.880 --> 00:20:38.359
<v Speaker 3>No, you go.

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00:20:38.640 --> 00:20:42.519
<v Speaker 2>Something massive, something with incredible energy, had to generate it

421
00:20:42.559 --> 00:20:45.200
<v Speaker 2>and push it out onto this specific plunging orbit.

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00:20:45.359 --> 00:20:47.920
<v Speaker 3>And this is where the sheer detective work of modern

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00:20:47.960 --> 00:20:51.839
<v Speaker 3>astronomy comes into play. Astronomers couldn't just guess. They had

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00:20:51.839 --> 00:20:55.480
<v Speaker 3>to formulate hypotheses and examine a lineup of initial suspects.

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00:20:55.599 --> 00:20:56.519
<v Speaker 2>Let's hear the lineup.

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00:20:56.960 --> 00:21:00.319
<v Speaker 3>In an environment is densely packed and violently entered jetic

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00:21:00.400 --> 00:21:03.920
<v Speaker 3>as the galactic center, there are a few usual culprits

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00:21:03.960 --> 00:21:08.519
<v Speaker 3>responsible for generating loose, fast moving gas. The first suspect

429
00:21:08.519 --> 00:21:12.519
<v Speaker 3>on the list was stellar winds from massive.

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00:21:12.160 --> 00:21:14.480
<v Speaker 2>Stars massive stars blowing wind.

431
00:21:14.720 --> 00:21:18.119
<v Speaker 3>Massive stars, particularly O type stars or wolf rayed stars,

432
00:21:18.440 --> 00:21:22.839
<v Speaker 3>are incredibly hot, volatile, and luminous. Because they've burn so hot,

433
00:21:23.200 --> 00:21:26.920
<v Speaker 3>the radiation pressure pushing outward from their cores frequently overcomes

434
00:21:26.920 --> 00:21:27.319
<v Speaker 3>their own.

435
00:21:27.240 --> 00:21:29.279
<v Speaker 2>Gravity, so they just sort of fall apart outward.

436
00:21:29.440 --> 00:21:32.359
<v Speaker 3>Basically, they constantly blow off their outer layers into space

437
00:21:32.440 --> 00:21:34.799
<v Speaker 3>at thousands of kilometers per second right, So.

438
00:21:34.720 --> 00:21:38.119
<v Speaker 2>You have these giant stars just constantly sweating off massive

439
00:21:38.119 --> 00:21:40.920
<v Speaker 2>amounts of gas in all directions, flooding the area. That's

440
00:21:40.960 --> 00:21:41.960
<v Speaker 2>suspect number one.

441
00:21:42.079 --> 00:21:46.160
<v Speaker 3>The second major suspect was an explosive event, specifically something

442
00:21:46.200 --> 00:21:48.880
<v Speaker 3>like a nova an explosion. A nova occurs in a

443
00:21:48.920 --> 00:21:53.400
<v Speaker 3>binary system where a white dwarf star slowly siphons matter

444
00:21:53.559 --> 00:21:57.440
<v Speaker 3>off a companion star. When enough hydrogen accumulates on the

445
00:21:57.480 --> 00:22:00.920
<v Speaker 3>incredibly dense surface of the white dwarf, the pressure and

446
00:22:00.960 --> 00:22:04.000
<v Speaker 3>temperature reach a critical point and boom, and it triggers

447
00:22:04.000 --> 00:22:08.079
<v Speaker 3>a runaway thermonuclear explosion. This explosion doesn't destroy the star,

448
00:22:08.519 --> 00:22:12.039
<v Speaker 3>but it blasts a distinct spherical shell of gas violently

449
00:22:12.079 --> 00:22:13.559
<v Speaker 3>outward into the surrounding space.

450
00:22:13.680 --> 00:22:18.119
<v Speaker 2>So suspect number two is basically a colossal, recurring nuclear

451
00:22:18.160 --> 00:22:20.799
<v Speaker 2>bomb throwing off shrapnel in the form of gas.

452
00:22:20.839 --> 00:22:23.279
<v Speaker 3>That's one way to put it. Yes, And the third

453
00:22:23.279 --> 00:22:25.960
<v Speaker 3>suspect was tidal stripping. What's that This would be a

454
00:22:26.039 --> 00:22:29.799
<v Speaker 3>much more localized scenario where a perfectly normal, stable star

455
00:22:30.240 --> 00:22:32.599
<v Speaker 3>just happened to wander slightly too close to sgr A.

456
00:22:32.720 --> 00:22:35.559
<v Speaker 2>On its orbit, wrong place, wrong time, exactly.

457
00:22:36.240 --> 00:22:40.279
<v Speaker 3>The black holes immense gravity wouldn't swallow the star hold immediately,

458
00:22:40.640 --> 00:22:43.720
<v Speaker 3>but it would literally rip the outer gaseous envelopes right

459
00:22:43.759 --> 00:22:45.119
<v Speaker 3>off the star's surface.

460
00:22:44.839 --> 00:22:47.440
<v Speaker 2>So it basically mugs the star for its gas.

461
00:22:47.480 --> 00:22:50.880
<v Speaker 3>Yes, creating a trailing stream of material that would follow

462
00:22:50.920 --> 00:22:51.680
<v Speaker 3>the star's path.

463
00:22:52.160 --> 00:22:56.839
<v Speaker 2>Okay, so you have three very different, very plausible suspects.

464
00:22:57.400 --> 00:23:00.880
<v Speaker 2>A massive star just blowing aggressively in the wind, a

465
00:23:00.920 --> 00:23:04.400
<v Speaker 2>star exploding in a thermonuclear blast, or an unlucky star

466
00:23:04.480 --> 00:23:07.720
<v Speaker 2>getting mugged for its outer layers by the supermassive black hole.

467
00:23:07.960 --> 00:23:08.440
<v Speaker 3>Correct.

468
00:23:08.599 --> 00:23:11.039
<v Speaker 2>If you are an astronomer, how do you even begin

469
00:23:11.119 --> 00:23:13.680
<v Speaker 2>to figure out which one is the actual culprit? I mean,

470
00:23:13.720 --> 00:23:16.319
<v Speaker 2>we talked earlier about the twenty six thousand light years

471
00:23:16.359 --> 00:23:19.880
<v Speaker 2>of thick galactic dust sitting between Earth and the galactic center.

472
00:23:20.000 --> 00:23:21.160
<v Speaker 3>It's a huge problem.

473
00:23:21.240 --> 00:23:23.759
<v Speaker 2>If I look towards Sagittarius with a normal telescope, I

474
00:23:23.799 --> 00:23:26.119
<v Speaker 2>just see a dark patch of nothing because the dust

475
00:23:26.200 --> 00:23:29.079
<v Speaker 2>blocks all the visible light. How do you isolate the

476
00:23:29.079 --> 00:23:31.079
<v Speaker 2>clues when you can't even see the crime scene with

477
00:23:31.119 --> 00:23:31.960
<v Speaker 2>standard optics.

478
00:23:32.200 --> 00:23:35.440
<v Speaker 3>The dust is the ultimate barrier. Visible light, the kind

479
00:23:35.480 --> 00:23:39.400
<v Speaker 3>our eyes see gets scattered and absorbed by the interstellar dust.

480
00:23:39.480 --> 00:23:41.880
<v Speaker 3>Particles long before it reaches Earth, so.

481
00:23:41.799 --> 00:23:43.559
<v Speaker 2>You have to use a different kind of light.

482
00:23:43.680 --> 00:23:47.240
<v Speaker 3>Exactly to pierce that twenty six thousand light year veil

483
00:23:47.279 --> 00:23:51.559
<v Speaker 3>of dust. Astronomers cannot rely on visible light. They must

484
00:23:51.559 --> 00:23:53.319
<v Speaker 3>observe in the infrared.

485
00:23:52.880 --> 00:23:56.240
<v Speaker 2>Spectrum because infrared has longer wavelength.

486
00:23:55.960 --> 00:23:59.839
<v Speaker 3>Yes, infrared light has longer wavelengths than visible light, allowing

487
00:23:59.880 --> 00:24:03.640
<v Speaker 3>it to literally slip past the microscopic dust grains and

488
00:24:03.759 --> 00:24:06.440
<v Speaker 3>travel all the way across the galaxy to our telescopes.

489
00:24:06.519 --> 00:24:09.920
<v Speaker 3>That is so convenient, But simply using an infrared camera

490
00:24:10.319 --> 00:24:12.440
<v Speaker 3>isn't enough. When you are trying to track something as

491
00:24:12.440 --> 00:24:15.440
<v Speaker 3>small as an Earth mass cloud of gas. You need

492
00:24:15.519 --> 00:24:19.160
<v Speaker 3>highly specialized instruments that can not only see the infrared light,

493
00:24:19.720 --> 00:24:23.680
<v Speaker 3>but measure the exact minute movements of the gas emitting

494
00:24:23.720 --> 00:24:26.799
<v Speaker 3>it right tracking it. The international team that finally cracked

495
00:24:26.799 --> 00:24:32.079
<v Speaker 3>this case relied on two specific, incredibly sophisticated instruments called

496
00:24:32.119 --> 00:24:35.880
<v Speaker 3>Sinfoni and Eris, mounted on the very large telescope in Chile.

497
00:24:36.240 --> 00:24:39.319
<v Speaker 2>But wait, infrared alone doesn't give you a perfectly sharp image,

498
00:24:39.359 --> 00:24:41.720
<v Speaker 2>right because even if the light makes it through the

499
00:24:41.720 --> 00:24:44.000
<v Speaker 2>galactic dust, it still has to get through our own

500
00:24:44.039 --> 00:24:47.680
<v Speaker 2>planet's atmosphere before it hits the telescope, Marrinshielder and our

501
00:24:47.720 --> 00:24:49.759
<v Speaker 2>atmosphere is a total mess.

502
00:24:50.039 --> 00:24:54.039
<v Speaker 3>That is the secondary and arguably more difficult challenge. Even

503
00:24:54.079 --> 00:24:56.839
<v Speaker 3>if you collect pristine infrared light from the center of

504
00:24:56.839 --> 00:25:01.359
<v Speaker 3>the galaxy, the moment it enters the Earth's atmosphere gets distorted. Right,

505
00:25:01.440 --> 00:25:05.920
<v Speaker 3>the atmosphere is constantly moving, churning with different temperatures and densities.

506
00:25:06.400 --> 00:25:10.200
<v Speaker 3>That turbulent air apps like a funhouse mirror, bending the

507
00:25:10.240 --> 00:25:11.119
<v Speaker 3>incoming light.

508
00:25:10.960 --> 00:25:13.039
<v Speaker 2>Waves, which is why stars twinkle.

509
00:25:13.279 --> 00:25:15.839
<v Speaker 3>That is the exact reason why stars appear to twinkle

510
00:25:15.839 --> 00:25:19.079
<v Speaker 3>to the naked eye. But in deep space astronomy, that

511
00:25:19.200 --> 00:25:22.759
<v Speaker 3>twinkling violently blurs the image, turning a precise point of

512
00:25:22.799 --> 00:25:25.440
<v Speaker 3>light into a smeared, unusable blob.

513
00:25:25.920 --> 00:25:28.119
<v Speaker 2>So how do Symphony and Eris fix that?

514
00:25:28.680 --> 00:25:30.519
<v Speaker 3>To solve this, they are equipped with one of the

515
00:25:30.519 --> 00:25:34.799
<v Speaker 3>most important technological leaps in modern astronomy, adaptive optics.

516
00:25:34.960 --> 00:25:37.759
<v Speaker 2>Adaptive optics I've read about this and it honestly sounds

517
00:25:37.799 --> 00:25:38.599
<v Speaker 2>like science fiction.

518
00:25:38.960 --> 00:25:39.559
<v Speaker 3>It really does.

519
00:25:39.720 --> 00:25:43.039
<v Speaker 2>Instead of just building a bigger static mirror, they build

520
00:25:43.039 --> 00:25:45.480
<v Speaker 2>a mirror that constantly changes its own shape to fight

521
00:25:45.480 --> 00:25:46.240
<v Speaker 2>the atmosphere.

522
00:25:46.440 --> 00:25:50.839
<v Speaker 3>It is a phenomenal feat of engineering. A system utilizing

523
00:25:50.880 --> 00:25:56.559
<v Speaker 3>adaptive optics often shoots a powerful, precisely calibrated laser beam

524
00:25:57.119 --> 00:25:58.319
<v Speaker 3>straight up into the night.

525
00:25:58.200 --> 00:26:00.799
<v Speaker 2>Sky well laser beam like a Sci Fi Yes.

526
00:26:01.319 --> 00:26:03.359
<v Speaker 3>That laser hits the sodium layer high in the upper

527
00:26:03.400 --> 00:26:07.440
<v Speaker 3>atmosphere and causes it to glow, creating an artificial guide

528
00:26:07.480 --> 00:26:10.480
<v Speaker 3>star right next to the object the telescope is trying

529
00:26:10.519 --> 00:26:11.000
<v Speaker 3>to observe.

530
00:26:11.119 --> 00:26:11.400
<v Speaker 2>Wow.

531
00:26:11.480 --> 00:26:14.680
<v Speaker 3>Okay, Because the telescope system knows exactly what that artificial

532
00:26:14.720 --> 00:26:17.599
<v Speaker 3>laser star should look like, a computer analyzes how the

533
00:26:17.640 --> 00:26:19.920
<v Speaker 3>atmosphere is currently blurring and distorting.

534
00:26:19.519 --> 00:26:22.119
<v Speaker 2>It, so it measures the distortion in real time.

535
00:26:22.359 --> 00:26:25.400
<v Speaker 3>The computer runs these calculations hundreds of times a second

536
00:26:25.720 --> 00:26:28.880
<v Speaker 3>and then sends signals to a secondary paper thin, deformable

537
00:26:28.920 --> 00:26:30.480
<v Speaker 3>mirror inside the telescope, and.

538
00:26:30.440 --> 00:26:31.960
<v Speaker 2>It actually bends the mirror.

539
00:26:32.079 --> 00:26:35.519
<v Speaker 3>Yes, tiny actuators behind that mirror physically push and pull

540
00:26:35.519 --> 00:26:38.680
<v Speaker 3>its surface, warping it in real time to perfectly cancel

541
00:26:38.720 --> 00:26:39.920
<v Speaker 3>out the atmospheric distortion.

542
00:26:40.200 --> 00:26:41.359
<v Speaker 2>That is unbelievable.

543
00:26:41.480 --> 00:26:44.599
<v Speaker 3>It essentially removes the Earth's atmosphere from the equation entirely,

544
00:26:44.960 --> 00:26:47.920
<v Speaker 3>giving ground based telescopes a level of sharpness and resolution

545
00:26:48.359 --> 00:26:52.160
<v Speaker 3>that rivals or sometimes even exceeds space telescopes like Hubble.

546
00:26:52.200 --> 00:26:55.519
<v Speaker 2>Okay, so just to recap the sheer amount of technology

547
00:26:55.519 --> 00:26:59.759
<v Speaker 2>involved here, they are using infrared sensors to slice through

548
00:26:59.839 --> 00:27:03.599
<v Speaker 2>twenty six thousand light years of thick galactic dust, right,

549
00:27:03.920 --> 00:27:06.319
<v Speaker 2>and then they are shooting lasers into the sky to

550
00:27:06.400 --> 00:27:09.920
<v Speaker 2>physically warp a mirror hundreds of times a second to

551
00:27:10.000 --> 00:27:11.559
<v Speaker 2>cancel out the Earth's atmosphere.

552
00:27:11.599 --> 00:27:12.680
<v Speaker 3>It's quite the setup.

553
00:27:12.880 --> 00:27:16.839
<v Speaker 2>They finally have a crystal clear, magically sharp view of

554
00:27:16.880 --> 00:27:20.880
<v Speaker 2>the galactic center. But what are Sinphoni and Eris actually

555
00:27:20.960 --> 00:27:23.480
<v Speaker 2>doing with that clear view Because they aren't just taking

556
00:27:23.519 --> 00:27:26.559
<v Speaker 2>a nice polaroid picture of the gas clouds. No, they

557
00:27:26.559 --> 00:27:28.880
<v Speaker 2>are spectrographs. They are breaking the light down.

558
00:27:29.000 --> 00:27:32.759
<v Speaker 3>Spectroscopy is arguably the most powerful tool in astronomer has.

559
00:27:33.359 --> 00:27:36.160
<v Speaker 3>It is the science of capturing light and breaking it

560
00:27:36.200 --> 00:27:39.759
<v Speaker 3>down into its component colors or specific wavelengths.

561
00:27:39.240 --> 00:27:40.680
<v Speaker 2>Like a prism breaks white light into a.

562
00:27:40.720 --> 00:27:43.880
<v Speaker 3>Rainbow, exactly like that. The reason this is so vital

563
00:27:44.000 --> 00:27:46.839
<v Speaker 3>is that different chemical elements, when they are heated and energized,

564
00:27:47.119 --> 00:27:50.480
<v Speaker 3>don't just glow a generic color. They emit light at

565
00:27:50.599 --> 00:27:55.319
<v Speaker 3>very specific, mathematically precise signature. Wavelengths like a barcode. It

566
00:27:55.400 --> 00:27:58.279
<v Speaker 3>is exactly like a chemical fingerprint. If you can see

567
00:27:58.279 --> 00:28:01.559
<v Speaker 3>the fingerprint, you know exactly what element is present. For

568
00:28:01.640 --> 00:28:07.359
<v Speaker 3>this particular investigation, the team programmed Symphony and eris to

569
00:28:07.440 --> 00:28:12.119
<v Speaker 3>focus specifically on something called the hydrogen bracket gamma emission line.

570
00:28:12.200 --> 00:28:15.359
<v Speaker 2>Okay, let's slow down and really explain that, because hydrogen

571
00:28:15.440 --> 00:28:19.000
<v Speaker 2>bracket gamma emission line sounds incredibly intimidating.

572
00:28:19.079 --> 00:28:19.759
<v Speaker 3>It's a mouthful.

573
00:28:19.920 --> 00:28:22.759
<v Speaker 2>We establish that the g clouds are mostly made of hydrogen.

574
00:28:23.400 --> 00:28:26.319
<v Speaker 2>What is the specific line and why is it the

575
00:28:26.400 --> 00:28:27.480
<v Speaker 2>key to tracking them?

576
00:28:27.880 --> 00:28:30.160
<v Speaker 3>To understand the bracket gamma line, we have to zoom

577
00:28:30.160 --> 00:28:32.759
<v Speaker 3>all the way down to the quantum level of a

578
00:28:32.799 --> 00:28:34.119
<v Speaker 3>single hydrogen atom.

579
00:28:34.200 --> 00:28:35.279
<v Speaker 2>Okay, shrinking down.

580
00:28:35.519 --> 00:28:38.400
<v Speaker 3>A hydrogen atom consists of one proton in the center

581
00:28:38.640 --> 00:28:41.839
<v Speaker 3>and one electron orbiting it. Now that electron can't just

582
00:28:41.960 --> 00:28:45.000
<v Speaker 3>orbit wherever it wants. It is restricted to very specific

583
00:28:45.279 --> 00:28:46.960
<v Speaker 3>fixed energy levels or.

584
00:28:47.000 --> 00:28:48.960
<v Speaker 2>Shells like rungs on a ladder.

585
00:28:49.279 --> 00:28:52.559
<v Speaker 3>Good analogy. When the hydrogen atom is sitting in a calm,

586
00:28:52.599 --> 00:28:56.000
<v Speaker 3>cold environment, the electron stays in its lowest energy level,

587
00:28:56.119 --> 00:28:59.200
<v Speaker 3>the ground state. But the environment in your SAGITTARIUSA is

588
00:28:59.240 --> 00:28:59.960
<v Speaker 3>anything but calm.

589
00:29:00.200 --> 00:29:01.480
<v Speaker 2>Right. It's a cosmic mosh pit.

590
00:29:01.720 --> 00:29:05.440
<v Speaker 3>It is flooded with intense, high energy ultraviolet radiation from

591
00:29:05.480 --> 00:29:09.279
<v Speaker 3>surrounding stars. When that radiation hits a hydrogen atom in

592
00:29:09.279 --> 00:29:13.519
<v Speaker 3>the g cloud, it transfers energy to the electron, bumping

593
00:29:13.519 --> 00:29:15.640
<v Speaker 3>it up to a much higher energy level. Let's say

594
00:29:15.640 --> 00:29:17.000
<v Speaker 3>it bumps it all the way up to the seventh

595
00:29:17.079 --> 00:29:17.720
<v Speaker 3>energy level.

596
00:29:17.880 --> 00:29:20.640
<v Speaker 2>But electrons are inherently lazy, right. They don't like being

597
00:29:20.680 --> 00:29:22.640
<v Speaker 2>highly energized. They want to drop back down to where

598
00:29:22.640 --> 00:29:23.759
<v Speaker 2>they started exactly.

599
00:29:23.960 --> 00:29:27.880
<v Speaker 3>The excited state is unstable. Almost immediately, that electron will

600
00:29:27.920 --> 00:29:30.839
<v Speaker 3>drop back down to a lower energy level. But energy

601
00:29:30.880 --> 00:29:33.119
<v Speaker 3>cannot be destroyed. It has to go somewhere, so it

602
00:29:33.160 --> 00:29:36.160
<v Speaker 3>spits it out. So as the electron drops, the atom

603
00:29:36.279 --> 00:29:39.480
<v Speaker 3>releases that exact packet of excess energy in the form

604
00:29:39.519 --> 00:29:42.240
<v Speaker 3>of a photon, a single particle of light. And here

605
00:29:42.319 --> 00:29:45.799
<v Speaker 3>is the crucial mechanism. When an electron in a hydrogen

606
00:29:45.799 --> 00:29:48.839
<v Speaker 3>atom drops specifically from the seventh energy level down to

607
00:29:48.880 --> 00:29:49.359
<v Speaker 3>the fourth.

608
00:29:49.240 --> 00:29:51.039
<v Speaker 2>Energy level Okay, seven to four, the.

609
00:29:51.000 --> 00:29:54.839
<v Speaker 3>Photon it releases has an exact unchanging wavelength of two

610
00:29:54.839 --> 00:29:58.880
<v Speaker 3>point one sixty six microns. That specific wavelength of infrared

611
00:29:58.920 --> 00:30:00.839
<v Speaker 3>light is what we call the brack Gamba line.

612
00:30:01.000 --> 00:30:05.200
<v Speaker 2>So by tuning these massive adaptive optics enabled telescopes in

613
00:30:05.279 --> 00:30:08.440
<v Speaker 2>Chile to ignore all the chaotic blinding light of the

614
00:30:08.599 --> 00:30:11.559
<v Speaker 2>millions of stars in the galactic center right, filtering all

615
00:30:11.559 --> 00:30:14.799
<v Speaker 2>that out and looking only for that one hyper specific

616
00:30:15.000 --> 00:30:18.240
<v Speaker 2>two point one sixty six micron shade of infrared light.

617
00:30:18.599 --> 00:30:21.759
<v Speaker 2>They can essentially put on night vision goggles that only

618
00:30:21.880 --> 00:30:24.400
<v Speaker 2>highlight hot energized hydrogen gas.

619
00:30:24.559 --> 00:30:25.759
<v Speaker 3>That's exactly what they're doing.

620
00:30:25.839 --> 00:30:28.279
<v Speaker 2>They can see exactly where the g clouds are against

621
00:30:28.279 --> 00:30:28.839
<v Speaker 2>the darkness.

622
00:30:28.920 --> 00:30:31.200
<v Speaker 3>They can see exactly where it is. But more importantly,

623
00:30:31.319 --> 00:30:34.279
<v Speaker 3>spectroscopy allows them to see exactly how fast it is

624
00:30:34.319 --> 00:30:36.279
<v Speaker 3>moving toward or away from us.

625
00:30:36.400 --> 00:30:38.079
<v Speaker 2>Oh, because of the movement of the light.

626
00:30:38.440 --> 00:30:40.759
<v Speaker 3>This is the crucial leap that turns a static picture

627
00:30:40.799 --> 00:30:44.079
<v Speaker 3>into a three dimensional moving map. It relies on the

628
00:30:44.079 --> 00:30:44.920
<v Speaker 3>Doppler effect.

629
00:30:45.279 --> 00:30:46.920
<v Speaker 2>Ah, like the ambulance siren.

630
00:30:47.079 --> 00:30:50.039
<v Speaker 3>Yes, the same physical phenomenon that makes an ambulance siren

631
00:30:50.119 --> 00:30:53.240
<v Speaker 3>pitch higher as it drives toward you and pitch lower

632
00:30:53.240 --> 00:30:55.559
<v Speaker 3>as it drives away applies to light waves.

633
00:30:55.680 --> 00:30:57.799
<v Speaker 2>Okay, so how does that work with the gas clouds?

634
00:30:58.200 --> 00:31:00.799
<v Speaker 3>If a clump of hydrogen gas in this is moving

635
00:31:00.839 --> 00:31:03.359
<v Speaker 3>physically closer to Earth as it orbits the black hole,

636
00:31:03.839 --> 00:31:06.839
<v Speaker 3>the light waves it emits get slightly compressed.

637
00:31:06.519 --> 00:31:07.559
<v Speaker 2>So they squish together.

638
00:31:07.799 --> 00:31:10.920
<v Speaker 3>Yes, that two point one sixty six micron bracket gamma

639
00:31:10.920 --> 00:31:15.119
<v Speaker 3>line gets squished to a slightly shorter wavelength, shifting it

640
00:31:15.160 --> 00:31:18.240
<v Speaker 3>toward the blue end of the spectrum a blue shift. Conversely,

641
00:31:18.559 --> 00:31:20.759
<v Speaker 3>if the gas is moving away from us, the light

642
00:31:20.799 --> 00:31:24.400
<v Speaker 3>wave stretches, shifting to a slightly longer wavelength toward the

643
00:31:24.440 --> 00:31:26.559
<v Speaker 3>red end of the spectrum, a red shift.

644
00:31:26.920 --> 00:31:31.839
<v Speaker 2>So by carefully measuring those minute microscopic shifts in the

645
00:31:31.880 --> 00:31:36.599
<v Speaker 2>wavelength what astronomers call radial velocity right exactly, and combining

646
00:31:36.640 --> 00:31:39.319
<v Speaker 2>that with the exact physical position of the gas on

647
00:31:39.359 --> 00:31:42.799
<v Speaker 2>the sky over several years of observation, they aren't just

648
00:31:42.839 --> 00:31:46.880
<v Speaker 2>taking a picture. They are mathematically reconstructing the exact three

649
00:31:46.920 --> 00:31:50.640
<v Speaker 2>dimensional speed and trajectory of every single glowing clump in

650
00:31:50.640 --> 00:31:51.039
<v Speaker 2>that river.

651
00:31:51.240 --> 00:31:53.119
<v Speaker 3>It is incredibly precise work.

652
00:31:53.240 --> 00:31:56.200
<v Speaker 2>It's like hitting rewind on a cosmic videotape. They didn't

653
00:31:56.200 --> 00:31:58.480
<v Speaker 2>just see a cloud of gas. They mapped exactly where

654
00:31:58.480 --> 00:32:01.839
<v Speaker 2>it was going, and, most important for our mystery, exactly

655
00:32:01.839 --> 00:32:02.640
<v Speaker 2>where it came from.

656
00:32:02.680 --> 00:32:05.359
<v Speaker 3>And when they finally took all that data and plotted

657
00:32:05.400 --> 00:32:07.680
<v Speaker 3>the complete three D orbits of G one, G two

658
00:32:08.279 --> 00:32:11.640
<v Speaker 3>and the newly discovered third clump over time, the math

659
00:32:11.720 --> 00:32:13.079
<v Speaker 3>revealed something profound.

660
00:32:13.240 --> 00:32:14.359
<v Speaker 2>What did the maths show them?

661
00:32:14.640 --> 00:32:17.720
<v Speaker 3>When they overlaid the calculated orbits of all three clumps?

662
00:32:18.160 --> 00:32:20.559
<v Speaker 3>They found that they all travel on paths with almost

663
00:32:20.559 --> 00:32:27.039
<v Speaker 3>identical orientations, eccentricities, and inclinations. Wow. This raises an important question.

664
00:32:28.000 --> 00:32:31.640
<v Speaker 3>What are the actual odds of that happening completely by chance?

665
00:32:32.079 --> 00:32:33.119
<v Speaker 2>Probably pretty low.

666
00:32:33.480 --> 00:32:36.279
<v Speaker 3>You have to consider the environment. The galactic center is

667
00:32:36.319 --> 00:32:41.400
<v Speaker 3>a chaotic, turbulent mess, swarming with millions of stars, competing

668
00:32:41.440 --> 00:32:46.799
<v Speaker 3>gravitational pulls, random gas clouds, and intense radiation pressure.

669
00:32:46.920 --> 00:32:48.559
<v Speaker 2>Right, things are just bouncing everywhere.

670
00:32:48.680 --> 00:32:53.960
<v Speaker 3>The mathematical probability of three distinct, entirely unrelated gas clouds

671
00:32:54.519 --> 00:32:59.480
<v Speaker 3>randomly falling into the exact same, highly specific, deeply plunging

672
00:32:59.519 --> 00:33:03.599
<v Speaker 3>elong orbit around the black hole is vanishingly small. It

673
00:33:03.680 --> 00:33:05.880
<v Speaker 3>borders on statistical impossibility.

674
00:33:05.960 --> 00:33:09.240
<v Speaker 2>It's like finding three different people from three entirely different

675
00:33:09.240 --> 00:33:12.480
<v Speaker 2>countries who somehow ended up walking the exact same convoluted

676
00:33:12.480 --> 00:33:14.920
<v Speaker 2>path through times square on New Year's eve down to

677
00:33:14.960 --> 00:33:17.759
<v Speaker 2>the exact footstep completely by coincidence.

678
00:33:17.799 --> 00:33:19.559
<v Speaker 3>Yes, a very good analogy, It just doesn't.

679
00:33:19.319 --> 00:33:20.680
<v Speaker 2>Happen in a chaotic system.

680
00:33:21.000 --> 00:33:23.960
<v Speaker 3>The data proved beyond a reasonable shadow of a doubt

681
00:33:24.319 --> 00:33:28.079
<v Speaker 3>that these were not unrelated phenomena. The shared orbital parameters

682
00:33:28.119 --> 00:33:29.559
<v Speaker 3>were the definitive smoking gun.

683
00:33:29.680 --> 00:33:30.599
<v Speaker 2>So they are connected.

684
00:33:30.720 --> 00:33:34.359
<v Speaker 3>They must share a single localized point of origin. Finding

685
00:33:34.400 --> 00:33:37.359
<v Speaker 3>the shared orbit is what transformed these isolated sightings of

686
00:33:37.400 --> 00:33:41.400
<v Speaker 3>G one and G two from mere curiosities into a connected,

687
00:33:41.799 --> 00:33:43.400
<v Speaker 3>trackable timeline of events.

688
00:33:43.480 --> 00:33:47.000
<v Speaker 2>So the detectives have their clues. They have the chemical footprint,

689
00:33:47.640 --> 00:33:50.680
<v Speaker 2>the hot ionized hydrogen glowing at two point one sixty

690
00:33:50.759 --> 00:33:55.200
<v Speaker 2>six microns. They have the orbital footprint, this incredibly specific

691
00:33:55.240 --> 00:33:58.640
<v Speaker 2>plunging path that bypasses a normal accretion disc and goes

692
00:33:58.680 --> 00:34:01.279
<v Speaker 2>straight toward the black hole, and they have the speed.

693
00:34:01.680 --> 00:34:04.720
<v Speaker 2>So they take all this incredibly precise, massive amount of

694
00:34:04.759 --> 00:34:07.640
<v Speaker 2>data gathered by Sinfona and the Ears, they plug it

695
00:34:07.640 --> 00:34:11.000
<v Speaker 2>into their computers and they hit the cosmic rewind button.

696
00:34:10.840 --> 00:34:13.719
<v Speaker 3>Racing the entire G one two three streamer backward through

697
00:34:13.719 --> 00:34:14.679
<v Speaker 3>space and time.

698
00:34:14.519 --> 00:34:17.000
<v Speaker 2>Following the river up to its source, and the trail

699
00:34:17.079 --> 00:34:20.320
<v Speaker 2>lands squarely on one specific suspect from our lineup. They

700
00:34:20.400 --> 00:34:22.039
<v Speaker 2>finally unmasked the culprit.

701
00:34:22.199 --> 00:34:25.800
<v Speaker 3>Yes, the culmination of all this tracking was incredibly precise

702
00:34:26.360 --> 00:34:30.440
<v Speaker 3>by mathematically following the trajectory of the streamer backward, both

703
00:34:30.480 --> 00:34:33.960
<v Speaker 3>in its physical spatial position and its radial velocity.

704
00:34:34.000 --> 00:34:34.679
<v Speaker 2>Where did it lead?

705
00:34:35.239 --> 00:34:38.800
<v Speaker 3>The path points directly back to a very specific massive

706
00:34:38.840 --> 00:34:42.320
<v Speaker 3>star system. This system is located in what astronomer is

707
00:34:42.360 --> 00:34:46.920
<v Speaker 3>called the clockwise disc, a distinct rotating disc of massive

708
00:34:47.039 --> 00:34:50.840
<v Speaker 3>young stars that orbit SGRA at a distance of about

709
00:34:50.840 --> 00:34:51.880
<v Speaker 3>a tenth of a parsec.

710
00:34:52.039 --> 00:34:54.119
<v Speaker 2>A tenth of a parsec, so pretty close.

711
00:34:53.920 --> 00:34:56.840
<v Speaker 3>Very close in galactic terms, and the specific star system

712
00:34:56.880 --> 00:34:59.800
<v Speaker 3>the streamer points to is called Iris sixteen.

713
00:34:59.519 --> 00:35:03.719
<v Speaker 2>Sw IRS sixteen sw I've always thought it sounds like

714
00:35:03.760 --> 00:35:06.480
<v Speaker 2>a tax form or maybe an obscure radio station.

715
00:35:06.880 --> 00:35:09.119
<v Speaker 3>It does lack a certain poetry, it really does.

716
00:35:09.320 --> 00:35:11.519
<v Speaker 2>But it's actually something so much cooler and so much

717
00:35:11.559 --> 00:35:14.679
<v Speaker 2>more violently energetic than just a single normal star. It's

718
00:35:14.960 --> 00:35:16.639
<v Speaker 2>a contact binary star.

719
00:35:16.559 --> 00:35:18.119
<v Speaker 3>A very extreme type of system.

720
00:35:18.199 --> 00:35:21.159
<v Speaker 2>Let's really break that concept down, because this specific type

721
00:35:21.199 --> 00:35:24.039
<v Speaker 2>of star system is the physical engine driving the whole operation.

722
00:35:24.559 --> 00:35:27.519
<v Speaker 2>What exactly makes a contact binary so different from the

723
00:35:27.559 --> 00:35:28.559
<v Speaker 2>stars we are used to.

724
00:35:28.400 --> 00:35:32.159
<v Speaker 3>To understand the extreme nature of IRS sixteen SW, we

725
00:35:32.280 --> 00:35:35.800
<v Speaker 3>have to look at how stars live. Most stars, like

726
00:35:35.840 --> 00:35:40.360
<v Speaker 3>our own son, are solitary objects, comfortably dominating their local

727
00:35:40.360 --> 00:35:41.400
<v Speaker 3>solar system.

728
00:35:41.159 --> 00:35:42.480
<v Speaker 2>Right just hanging out alone.

729
00:35:42.519 --> 00:35:44.599
<v Speaker 3>But a huge percentage of stars in the universe are

730
00:35:44.639 --> 00:35:48.719
<v Speaker 3>actually born in pairs orbiting a common center of gravity.

731
00:35:48.920 --> 00:35:50.320
<v Speaker 3>These are binary systems.

732
00:35:50.400 --> 00:35:52.360
<v Speaker 2>Okay, two stars orbiting each other.

733
00:35:52.519 --> 00:35:55.199
<v Speaker 3>Now. In a typical binary system, there is a comfortable

734
00:35:55.360 --> 00:35:58.400
<v Speaker 3>vast distance between the two stars. They orbit each other

735
00:35:58.440 --> 00:36:02.239
<v Speaker 3>calmly over years or central. But IRS sixteen s W

736
00:36:02.719 --> 00:36:05.039
<v Speaker 3>is an extreme, highly evolved case.

737
00:36:05.119 --> 00:36:07.199
<v Speaker 2>They are not keeping their distance, not at all.

738
00:36:07.440 --> 00:36:11.920
<v Speaker 3>It consists of two incredibly massive, fiercely hot stars that

739
00:36:11.960 --> 00:36:14.719
<v Speaker 3>are orbiting each other so closely that their outer atmospheres

740
00:36:14.760 --> 00:36:17.320
<v Speaker 3>their stellar envelopes are practically.

741
00:36:16.880 --> 00:36:18.480
<v Speaker 2>Touching like their atmospheres are touching.

742
00:36:18.599 --> 00:36:21.960
<v Speaker 3>Yes, they are locked in this incredibly tight, incredibly fast,

743
00:36:22.199 --> 00:36:26.239
<v Speaker 3>and incredibly violent gravitational embrace. The orbital period is so

744
00:36:26.320 --> 00:36:29.880
<v Speaker 3>short and the proximity so close that the stars are

745
00:36:29.880 --> 00:36:32.880
<v Speaker 3>physically distorting each other's shapes into tear drops due to

746
00:36:32.960 --> 00:36:34.400
<v Speaker 3>the mutual gravitational pull.

747
00:36:34.760 --> 00:36:38.840
<v Speaker 2>Tear drop shaped stars that is so bizarre to think about,

748
00:36:39.559 --> 00:36:42.079
<v Speaker 2>and because they are massive stars, they aren't just sitting

749
00:36:42.159 --> 00:36:44.280
<v Speaker 2>there quietly, calmly glowing right.

750
00:36:44.559 --> 00:36:45.119
<v Speaker 3>Definitely not.

751
00:36:45.400 --> 00:36:48.599
<v Speaker 2>We mentioned earlier in our suspect lineup that massive stars

752
00:36:48.639 --> 00:36:52.599
<v Speaker 2>have intense stellar winds. A star like our Sun has

753
00:36:52.639 --> 00:36:56.239
<v Speaker 2>a solar wind, It pushes out a steady stream of particles,

754
00:36:56.519 --> 00:36:58.559
<v Speaker 2>which causes the auroras here on Earth.

755
00:36:58.599 --> 00:37:00.000
<v Speaker 3>A relatively gentle breeze.

756
00:37:00.239 --> 00:37:02.920
<v Speaker 2>But the stellar winds coming off massive stars like those

757
00:37:02.960 --> 00:37:06.800
<v Speaker 2>in IRS sixteen s W are on a completely different magnitude.

758
00:37:07.119 --> 00:37:10.320
<v Speaker 2>They are constantly blowing a literal hurricane of hot plasma

759
00:37:10.360 --> 00:37:13.280
<v Speaker 2>and gas off their surfaces at millions of miles an hour.

760
00:37:13.480 --> 00:37:14.000
<v Speaker 3>Millions.

761
00:37:14.039 --> 00:37:17.280
<v Speaker 2>So if you have two of these giant, volatile stars

762
00:37:17.320 --> 00:37:21.440
<v Speaker 2>practically rubbing against each other, both pushing out these colossal.

763
00:37:21.039 --> 00:37:25.239
<v Speaker 3>Winds, the resulting fluid dynamics are explosively complex. The researchers

764
00:37:25.239 --> 00:37:28.199
<v Speaker 3>didn't just assume this would create gas clouds. They ran

765
00:37:28.440 --> 00:37:34.079
<v Speaker 3>highly sophisticated three D hydrodynamical computer simulations to model exactly

766
00:37:34.119 --> 00:37:37.559
<v Speaker 3>what would happen to the gas in this very specific scenario.

767
00:37:37.199 --> 00:37:39.920
<v Speaker 2>And what happens when two stellar hurricanes hit each other.

768
00:37:40.320 --> 00:37:43.840
<v Speaker 3>When you have two massive stars in a contact binary,

769
00:37:44.440 --> 00:37:49.480
<v Speaker 3>both actively projecting intense stellar winds outward at thousands of

770
00:37:49.559 --> 00:37:53.239
<v Speaker 3>kilometers per second. Those winds don't just pass through each other,

771
00:37:53.480 --> 00:37:57.639
<v Speaker 3>they crash, They violently collide in the extremely narrow space

772
00:37:57.679 --> 00:37:58.639
<v Speaker 3>between the two stars.

773
00:37:58.719 --> 00:38:00.960
<v Speaker 2>Okay, I have an analogy for this, to try and

774
00:38:01.079 --> 00:38:05.000
<v Speaker 2>bring these massive astrophysical fluid dynamics down to Earth.

775
00:38:05.119 --> 00:38:06.639
<v Speaker 3>I love your analogies. Go for it.

776
00:38:06.719 --> 00:38:11.159
<v Speaker 2>Imagine you take two industrial strength gas powered leaf blowers.

777
00:38:11.440 --> 00:38:14.360
<v Speaker 2>You strap them to a table point, the nozzles directly

778
00:38:14.400 --> 00:38:16.880
<v Speaker 2>at each other, with maybe an inch of space between them,

779
00:38:17.199 --> 00:38:19.360
<v Speaker 2>and turn them both onto maximum power.

780
00:38:19.480 --> 00:38:21.440
<v Speaker 3>That sounds dangerous, very dangerous.

781
00:38:21.559 --> 00:38:24.400
<v Speaker 2>The air rushing out of both nozzles is incredibly fast,

782
00:38:24.719 --> 00:38:27.000
<v Speaker 2>but right in the middle and that one inch gap

783
00:38:27.039 --> 00:38:29.800
<v Speaker 2>where those two high speed air streams crash head on

784
00:38:29.840 --> 00:38:32.920
<v Speaker 2>into each other, the air suddenly has nowhere to go.

785
00:38:33.079 --> 00:38:33.599
<v Speaker 3>It's trapped.

786
00:38:33.679 --> 00:38:35.599
<v Speaker 2>It can't move forward, and it can't go backward. It

787
00:38:35.679 --> 00:38:40.239
<v Speaker 2>violently crashes, It compresses, and it forms this incredibly dense, turbulent,

788
00:38:40.360 --> 00:38:42.800
<v Speaker 2>high pressure nod of air right in the center. And

789
00:38:42.920 --> 00:38:46.599
<v Speaker 2>eventually the pressure in that central knot gets so overwhelmingly

790
00:38:46.719 --> 00:38:49.920
<v Speaker 2>high that chunks of that compressed air just have to

791
00:38:50.039 --> 00:38:52.800
<v Speaker 2>escape the trap. They get violently pushed out the sides,

792
00:38:53.079 --> 00:38:55.599
<v Speaker 2>blowing away as dense cohesive bursts.

793
00:38:55.920 --> 00:38:59.519
<v Speaker 3>That is an exceptionally accurate visualization of the shock physics

794
00:38:59.559 --> 00:38:59.840
<v Speaker 3>at play.

795
00:39:00.280 --> 00:39:02.599
<v Speaker 2>Really, the leaf blowers work absolutely.

796
00:39:03.199 --> 00:39:06.159
<v Speaker 3>When those stellar winds collide in the space between the

797
00:39:06.199 --> 00:39:09.800
<v Speaker 3>stars of IRS sixteen s W, the kinetic energy of

798
00:39:09.840 --> 00:39:12.639
<v Speaker 3>the collision has to go somewhere. It creates a massive

799
00:39:12.760 --> 00:39:16.320
<v Speaker 3>standing shockwave. Wow. The high pressure not created by this

800
00:39:16.400 --> 00:39:20.360
<v Speaker 3>collision compresses the gas to a tremendous degree. And here

801
00:39:20.440 --> 00:39:22.880
<v Speaker 3>is where it elegantly ties back to the optical physics

802
00:39:22.880 --> 00:39:25.880
<v Speaker 3>we discussed earlier regarding the glowing clumps.

803
00:39:25.480 --> 00:39:26.960
<v Speaker 2>The squared brightness thing.

804
00:39:27.039 --> 00:39:30.639
<v Speaker 3>Exactly, that violent collision compresses the local gas so much

805
00:39:31.000 --> 00:39:34.559
<v Speaker 3>that it crosses the crucial density threshold required to dramatically

806
00:39:34.639 --> 00:39:37.800
<v Speaker 3>increase its emission brightness. It becomes dense enough and hot

807
00:39:37.880 --> 00:39:40.400
<v Speaker 3>enough to glow brilliantly in the infrared spectrum.

808
00:39:40.400 --> 00:39:43.199
<v Speaker 2>So the leaf blowers, the colliding stellar winds are actually

809
00:39:43.199 --> 00:39:46.639
<v Speaker 2>manufacturing the glowing clumps in the river. The binary star

810
00:39:46.880 --> 00:39:48.400
<v Speaker 2>is literally a clump factory.

811
00:39:48.639 --> 00:39:53.360
<v Speaker 3>Precisely, the shockwave heavily compresses the gas as this compressed

812
00:39:53.360 --> 00:39:57.880
<v Speaker 3>material builds up in the collision zone, it becomes hydrodynamically unstable.

813
00:39:57.400 --> 00:39:58.159
<v Speaker 2>Gets pushed out.

814
00:39:58.159 --> 00:40:03.480
<v Speaker 3>Besides, eventually that dense pocketive gas detaches from the binary

815
00:40:03.519 --> 00:40:08.159
<v Speaker 3>star system entirely as an individual, highly cohesive clump rather

816
00:40:08.239 --> 00:40:09.519
<v Speaker 3>than just a diffew spray of.

817
00:40:09.480 --> 00:40:10.800
<v Speaker 2>Atoms, and that's free.

818
00:40:10.920 --> 00:40:13.519
<v Speaker 3>Once that dense clump is pushed outward and escapes the

819
00:40:13.559 --> 00:40:17.800
<v Speaker 3>immediate localized gravitational grip of the two orbiting stars, it

820
00:40:17.960 --> 00:40:20.360
<v Speaker 3>enters the wider environment of the galactic.

821
00:40:19.880 --> 00:40:21.519
<v Speaker 2>Center, where the big boss tucks over.

822
00:40:22.000 --> 00:40:26.679
<v Speaker 3>Immediately, it gets caught in the overwhelming overarching gravitational pull

823
00:40:26.719 --> 00:40:30.599
<v Speaker 3>of Sagittarius A. It gets yanked into that highly eccentric,

824
00:40:30.880 --> 00:40:34.440
<v Speaker 3>plunging orbit we tracked earlier, beginning its long inward journey

825
00:40:34.679 --> 00:40:37.199
<v Speaker 3>and officially joining the continuous flow of the G one

826
00:40:37.239 --> 00:40:38.119
<v Speaker 3>two three streamer.

827
00:40:38.199 --> 00:40:39.760
<v Speaker 2>That is incredible. But wait, if I put on my

828
00:40:39.800 --> 00:40:41.719
<v Speaker 2>skeptical hat for a second and look at the data.

829
00:40:41.800 --> 00:40:44.400
<v Speaker 2>Go ahead, If all these clumps G one, G two,

830
00:40:44.519 --> 00:40:46.920
<v Speaker 2>and the third clump are all being manufactured by and

831
00:40:46.960 --> 00:40:50.800
<v Speaker 2>ejected from the exact same binary star system IRS sixteen

832
00:40:50.960 --> 00:40:53.760
<v Speaker 2>s W, why aren't they on the exact same orbit.

833
00:40:53.960 --> 00:40:55.119
<v Speaker 3>That's a very fair question.

834
00:40:55.440 --> 00:40:59.480
<v Speaker 2>You mentioned earlier that their orbits have almost identical orientations,

835
00:40:59.599 --> 00:41:01.920
<v Speaker 2>and that was enough to prove a connection, But there

836
00:41:01.960 --> 00:41:05.840
<v Speaker 2>are small measurable differences in their paths. G one's orbit

837
00:41:05.880 --> 00:41:07.480
<v Speaker 2>isn't perfectly flushed with G two's.

838
00:41:07.639 --> 00:41:08.159
<v Speaker 3>No, it's not.

839
00:41:08.559 --> 00:41:11.480
<v Speaker 2>Doesn't that discrepancy throw a wrench in the entire theory?

840
00:41:11.760 --> 00:41:13.719
<v Speaker 2>If they come from the exact same gun, shouldn't they

841
00:41:13.760 --> 00:41:16.039
<v Speaker 2>follow the exact same bullet trajectory.

842
00:41:16.039 --> 00:41:19.639
<v Speaker 3>On a static stationary system, Yes, they would, But pointing

843
00:41:19.639 --> 00:41:23.639
<v Speaker 3>out those slight orbital differences actually strengthens the theory beautifully

844
00:41:23.679 --> 00:41:26.800
<v Speaker 3>because it proves the dynamic nature of the source. How So,

845
00:41:27.239 --> 00:41:30.239
<v Speaker 3>think about the physical reality of IRS sixteen s W.

846
00:41:30.719 --> 00:41:33.559
<v Speaker 3>It is a binary system, meaning those two massive stars

847
00:41:33.559 --> 00:41:37.719
<v Speaker 3>are constantly rapidly revolving around each other. But beyond that,

848
00:41:38.000 --> 00:41:42.199
<v Speaker 3>the entire binary system itself, the whole package is actively

849
00:41:42.320 --> 00:41:45.480
<v Speaker 3>orbiting around the supermassive black hole as part of that

850
00:41:45.599 --> 00:41:47.039
<v Speaker 3>clockwise disc of stars.

851
00:41:47.320 --> 00:41:48.960
<v Speaker 2>Eh. It's moving.

852
00:41:49.320 --> 00:41:53.559
<v Speaker 3>It is a moving, rotating, spinning platform in space. So

853
00:41:54.000 --> 00:41:57.639
<v Speaker 3>when the colliding stellar winds build up enough pressure and

854
00:41:57.679 --> 00:42:01.239
<v Speaker 3>eject a clump of gas, say the clump that became

855
00:42:01.360 --> 00:42:04.719
<v Speaker 3>G one, the binary star is located in one highly

856
00:42:04.719 --> 00:42:08.239
<v Speaker 3>specific position in its orbit around the black hole, facing

857
00:42:08.280 --> 00:42:11.679
<v Speaker 3>one specific direction and moving into specific velocity.

858
00:42:11.920 --> 00:42:13.960
<v Speaker 2>Ah, I get it. It's like throwing a baseball out

859
00:42:14.000 --> 00:42:16.679
<v Speaker 2>the window of a moving car. The speed and direction

860
00:42:16.760 --> 00:42:19.519
<v Speaker 2>of the car entirely affect the final trajectory of the

861
00:42:19.519 --> 00:42:20.480
<v Speaker 2>ball exactly.

862
00:42:21.079 --> 00:42:23.400
<v Speaker 3>The initial vector of the gas clump is a combination

863
00:42:23.519 --> 00:42:26.199
<v Speaker 3>of the ejection force and the underlying movement of the

864
00:42:26.239 --> 00:42:29.599
<v Speaker 3>star system itself. Now fast forward ten or twenty years

865
00:42:29.639 --> 00:42:32.239
<v Speaker 3>to when the collision zone builds up enough pressure to

866
00:42:32.280 --> 00:42:33.719
<v Speaker 3>eject the next major clump.

867
00:42:33.519 --> 00:42:35.880
<v Speaker 2>G two, the car has driven further down the road.

868
00:42:36.119 --> 00:42:40.480
<v Speaker 3>Exactly, in that intervening time, the binary star system IRS

869
00:42:40.519 --> 00:42:44.719
<v Speaker 3>sixteen SW has physically moved further along its own massive

870
00:42:44.840 --> 00:42:47.039
<v Speaker 3>orbit around the black hole. It is in a different

871
00:42:47.039 --> 00:42:48.079
<v Speaker 3>spatial location.

872
00:42:47.880 --> 00:42:48.719
<v Speaker 2>So the angles change.

873
00:42:48.760 --> 00:42:51.159
<v Speaker 3>The angles of ejection of change slightly relative to the

874
00:42:51.159 --> 00:42:54.000
<v Speaker 3>black hole. The rotational phase of the binary stars themselves

875
00:42:54.159 --> 00:42:56.639
<v Speaker 3>might be slightly different at the exact moment of ejection.

876
00:42:56.960 --> 00:42:58.079
<v Speaker 2>That makes perfect sense.

877
00:42:58.320 --> 00:43:01.760
<v Speaker 3>Therefore, the resulting orbital path of G two will be

878
00:43:01.800 --> 00:43:05.400
<v Speaker 3>profoundly similar to G one because it originated from the

879
00:43:05.440 --> 00:43:09.920
<v Speaker 3>same core gravitational zone. But it will inevitably have minute,

880
00:43:10.280 --> 00:43:12.679
<v Speaker 3>mathematically predictable differences.

881
00:43:12.360 --> 00:43:14.880
<v Speaker 2>Caused by the simple fact that the clump factory itself

882
00:43:14.960 --> 00:43:17.119
<v Speaker 2>is spinning and moving through space over time.

883
00:43:17.320 --> 00:43:21.079
<v Speaker 3>Precisely, when astrophysicists modeled the ejection of material from a

884
00:43:21.159 --> 00:43:26.480
<v Speaker 3>moving orbit matching IRS sixteen SW, the slight documented differences

885
00:43:26.519 --> 00:43:28.440
<v Speaker 3>in the orbits of G one, G two and the

886
00:43:28.440 --> 00:43:31.880
<v Speaker 3>third clump perfectly matched the modeled ordinal dynamics of a

887
00:43:31.920 --> 00:43:32.559
<v Speaker 3>moving source.

888
00:43:32.880 --> 00:43:36.880
<v Speaker 2>That is just It's incredibly satisfying when the physics puzzle

889
00:43:36.920 --> 00:43:38.519
<v Speaker 2>pieces fit together that perfectly.

890
00:43:38.639 --> 00:43:40.159
<v Speaker 3>That's what every scientist lives for.

891
00:43:40.320 --> 00:43:42.960
<v Speaker 2>You have the fluid dynamics of the colliding winds perfectly

892
00:43:42.960 --> 00:43:45.880
<v Speaker 2>explaining why the gas is hot, compress and clumpy enough

893
00:43:45.880 --> 00:43:49.119
<v Speaker 2>to glow brightly in the infrared. You have the macro

894
00:43:49.199 --> 00:43:52.559
<v Speaker 2>movement of the binary star system perfectly explaining this slight

895
00:43:52.679 --> 00:43:56.360
<v Speaker 2>measurable variations in the orbital paths of the distinct clumps

896
00:43:56.360 --> 00:44:00.639
<v Speaker 2>over decades. And you have the overall overarching graph vitational

897
00:44:00.679 --> 00:44:04.719
<v Speaker 2>trajectory pointing right down the barrel, delivering this material straight

898
00:44:04.760 --> 00:44:08.079
<v Speaker 2>to SAGITTARIUSA. It leaves absolutely no room for doubt.

899
00:44:08.360 --> 00:44:11.840
<v Speaker 3>It truly is a triumph of modern astronomy. It demonstrates

900
00:44:11.840 --> 00:44:15.039
<v Speaker 3>how observational data gathering, photons that have traveled for twenty

901
00:44:15.079 --> 00:44:20.440
<v Speaker 3>six thousand years, and theoretical hydrodynamical modeling can work perfectly

902
00:44:20.440 --> 00:44:24.239
<v Speaker 3>in tandem to solve a complex, multi variable mystery in

903
00:44:24.239 --> 00:44:26.119
<v Speaker 3>an environment we can never physically visit.

904
00:44:26.440 --> 00:44:29.079
<v Speaker 2>So, after taking this hour to really dig into the

905
00:44:29.119 --> 00:44:31.920
<v Speaker 2>mechanics of this, what does this all mean for our

906
00:44:32.039 --> 00:44:33.360
<v Speaker 2>understanding of the universe.

907
00:44:33.440 --> 00:44:35.119
<v Speaker 3>It's a huge paradigm shift.

908
00:44:34.960 --> 00:44:37.800
<v Speaker 2>When we step back from the specific infrared data points

909
00:44:37.840 --> 00:44:40.280
<v Speaker 2>and the orbital math and look at this whole story.

910
00:44:40.679 --> 00:44:44.159
<v Speaker 2>We've clearly moved past just solving a niche mystery about

911
00:44:44.199 --> 00:44:46.800
<v Speaker 2>some glowing gas clouds puzzling a few astronomers.

912
00:44:46.800 --> 00:44:49.519
<v Speaker 3>We have uncovered an entire ecosystem.

913
00:44:48.920 --> 00:44:53.199
<v Speaker 2>A majestic and frankly terrifying ecosystem operating continuously at the

914
00:44:53.239 --> 00:44:57.239
<v Speaker 2>center of our galaxy. It fundamentally changes the narrative. It's

915
00:44:57.239 --> 00:44:59.719
<v Speaker 2>not just a story about a dark, dormant black hole

916
00:44:59.760 --> 00:45:04.320
<v Speaker 2>are libitrarily passibly eating whatever unlucky material happens to wander

917
00:45:04.360 --> 00:45:05.079
<v Speaker 2>too close.

918
00:45:04.880 --> 00:45:05.519
<v Speaker 3>Are from it.

919
00:45:05.519 --> 00:45:09.239
<v Speaker 2>It is a highly structured, perfectly balanced, mechanically driven cycle.

920
00:45:09.679 --> 00:45:13.360
<v Speaker 2>You have this chaotic, dense disk of material swirling around

921
00:45:13.400 --> 00:45:16.800
<v Speaker 2>the black hole where massive volatile stars are born, yes

922
00:45:16.840 --> 00:45:21.239
<v Speaker 2>the clockwise disc. These stars live incredibly fierce short lives

923
00:45:21.599 --> 00:45:25.760
<v Speaker 2>and frequently pair up as these extreme violent contact binaries

924
00:45:25.800 --> 00:45:29.719
<v Speaker 2>like IRS sixteen s w their violent lives and constantly

925
00:45:29.719 --> 00:45:32.320
<v Speaker 2>colliding winds act as a mechanical factory.

926
00:45:32.119 --> 00:45:35.639
<v Speaker 3>Churning out these dense compressed clouds of hot plasma.

927
00:45:35.119 --> 00:45:38.360
<v Speaker 2>And those clouds inevitably get pulled inward by the massive

928
00:45:38.400 --> 00:45:42.639
<v Speaker 2>gravity gradient, stretching out and forming this glowing, structured river

929
00:45:42.760 --> 00:45:46.920
<v Speaker 2>that bypasses the slow accretion disc and delivers a slow, steady,

930
00:45:47.119 --> 00:45:51.119
<v Speaker 2>highly efficient drip of fuel directly to the supermassive black hole.

931
00:45:50.960 --> 00:45:53.159
<v Speaker 3>The black hole that anchors and dictates the gravity of

932
00:45:53.199 --> 00:45:54.039
<v Speaker 3>the entire system.

933
00:45:54.079 --> 00:45:57.400
<v Speaker 2>It's not a random feeding it is a continuous, self sustaining,

934
00:45:57.559 --> 00:45:58.800
<v Speaker 2>deeply connected loop.

935
00:45:59.000 --> 00:46:01.559
<v Speaker 3>And if we connect this localized discovery to the much

936
00:46:01.599 --> 00:46:06.800
<v Speaker 3>broader overarching picture of astrophysics and cosmology, the implications are profound. Also,

937
00:46:07.119 --> 00:46:10.320
<v Speaker 3>for decades, the scientific community has tended to study different

938
00:46:10.320 --> 00:46:13.960
<v Speaker 3>fields of astronomy in somewhat isolated silos out of sheer

939
00:46:14.000 --> 00:46:16.280
<v Speaker 3>necessity due to their complexity.

940
00:46:15.760 --> 00:46:17.079
<v Speaker 2>Because there's just too much to know.

941
00:46:17.400 --> 00:46:20.880
<v Speaker 3>Right, We have the field of stellar evolution, which focuses

942
00:46:21.119 --> 00:46:25.400
<v Speaker 3>entirely on how individual stars are born from nebulas, how

943
00:46:25.440 --> 00:46:28.320
<v Speaker 3>they live, how they burn their fuel, and how they

944
00:46:28.400 --> 00:46:29.199
<v Speaker 3>eventually died.

945
00:46:29.280 --> 00:46:30.360
<v Speaker 2>Okay, that's a one silo.

946
00:46:30.599 --> 00:46:33.800
<v Speaker 3>We have the field of interscullar gas dynamics, which relies

947
00:46:33.800 --> 00:46:37.199
<v Speaker 3>on heavy fluid mathematics to model how plasmas and atomic

948
00:46:37.239 --> 00:46:40.840
<v Speaker 3>clouds move shock and cool through the vacuum.

949
00:46:40.519 --> 00:46:42.039
<v Speaker 2>Of space Silo number two.

950
00:46:42.280 --> 00:46:44.639
<v Speaker 3>And then we have the entirely separate study of active

951
00:46:44.679 --> 00:46:48.639
<v Speaker 3>galactic nuclei and black hole feeding mechanisms, which tries to

952
00:46:48.719 --> 00:46:53.400
<v Speaker 3>understand how the dark, incredibly massive cores of galaxies grow,

953
00:46:53.760 --> 00:46:56.880
<v Speaker 3>emit radiation, and evolve over billions of years.

954
00:46:57.199 --> 00:46:59.280
<v Speaker 2>And what you were saying is that this single discovery

955
00:46:59.280 --> 00:47:02.239
<v Speaker 2>in our own galac center just grabs all three of

956
00:47:02.280 --> 00:47:05.880
<v Speaker 2>those massive, historically separate fields of study and ties them

957
00:47:05.920 --> 00:47:08.239
<v Speaker 2>tightly into a single, undeniable.

958
00:47:07.719 --> 00:47:13.599
<v Speaker 3>Knot precisely, it elegantly visibly proves that these cosmic processes

959
00:47:13.639 --> 00:47:18.159
<v Speaker 3>are not isolated phenomena happening independently of one another. Stellar revolution,

960
00:47:18.639 --> 00:47:22.440
<v Speaker 3>gas dynamics, and black hole feeding are intimately mechanically and

961
00:47:22.480 --> 00:47:23.320
<v Speaker 3>crucially linked.

962
00:47:23.559 --> 00:47:25.119
<v Speaker 2>They're all part of the same machine.

963
00:47:25.199 --> 00:47:27.599
<v Speaker 3>The life cycle of the stars residing in the galactic

964
00:47:27.639 --> 00:47:31.320
<v Speaker 3>center directly dictates the feeding habits, the energy output, and

965
00:47:31.440 --> 00:47:33.920
<v Speaker 3>ultimately the growth rate of the supermassive black hole.

966
00:47:34.039 --> 00:47:34.519
<v Speaker 2>Wow.

967
00:47:34.679 --> 00:47:37.239
<v Speaker 3>The violent death and volatility of matter happening on the

968
00:47:37.280 --> 00:47:40.920
<v Speaker 3>relatively small stellar scale acts as the direct fuel source

969
00:47:41.119 --> 00:47:44.239
<v Speaker 3>for the gravitational giant operating on the massive galactic scale.

970
00:47:44.320 --> 00:47:45.679
<v Speaker 2>It scales all the way up.

971
00:47:45.800 --> 00:47:48.239
<v Speaker 3>By observing the G one two three streamer and its

972
00:47:48.239 --> 00:47:51.920
<v Speaker 3>source IRS sixteen s W, we are seeing right here

973
00:47:51.920 --> 00:47:55.679
<v Speaker 3>in our own milky Way, a highly localized, perfectly observable

974
00:47:55.800 --> 00:48:00.440
<v Speaker 3>version of the exact physical processes that likely shape the evolution, growth,

975
00:48:00.480 --> 00:48:05.239
<v Speaker 3>and radiation output of entire galaxies across the entire observable universe.

976
00:48:05.320 --> 00:48:08.679
<v Speaker 3>That is just staggering. It proves that even in an

977
00:48:08.840 --> 00:48:13.119
<v Speaker 3>environment as violently chaotic, dense, and seemingly random as the

978
00:48:13.159 --> 00:48:17.239
<v Speaker 3>center of a galaxy, there is an underlying, beautiful mechanical

979
00:48:17.400 --> 00:48:21.320
<v Speaker 3>order to how mass is transferred, compressed, and ultimately consumed.

980
00:48:21.519 --> 00:48:23.840
<v Speaker 2>It really is breathtaking when you take a moment to

981
00:48:23.920 --> 00:48:27.320
<v Speaker 2>internalize the sheer scale and the mechanical perfection of it all.

982
00:48:27.440 --> 00:48:28.679
<v Speaker 3>It is a beautiful machine.

983
00:48:28.719 --> 00:48:31.840
<v Speaker 2>To briefly recap this incredible journey for you listening. It

984
00:48:31.880 --> 00:48:36.320
<v Speaker 2>all started with a mysterious, faint, glowing clump G two

985
00:48:36.960 --> 00:48:41.400
<v Speaker 2>spotted through the interstellar dust braving the seemingly insurmountable spaghetification

986
00:48:41.559 --> 00:48:44.079
<v Speaker 2>forces of a super massive black hole back.

987
00:48:43.920 --> 00:48:46.920
<v Speaker 3>In twenty twelve, and that single anomaly sparked everything.

988
00:48:47.119 --> 00:48:49.960
<v Speaker 2>That initial anomaly led to a decade of data mining

989
00:48:50.039 --> 00:48:52.800
<v Speaker 2>and the profound realization that G two, along with the

990
00:48:52.840 --> 00:48:55.320
<v Speaker 2>earlier clump G one, and a newly formed third clump,

991
00:48:55.599 --> 00:48:57.920
<v Speaker 2>weren't isolated random clouds at all.

992
00:48:57.840 --> 00:49:01.920
<v Speaker 3>But highly compressed illuminated rapids in a continuous flowing cosmic

993
00:49:02.039 --> 00:49:03.840
<v Speaker 3>river of hot plasma.

994
00:49:03.400 --> 00:49:08.239
<v Speaker 2>Diving straight towards SAGITTARIUSA. By pushing technology to its absolute limit,

995
00:49:08.719 --> 00:49:11.920
<v Speaker 2>utilizing mind bending adaptive optics to cancel out our own

996
00:49:11.960 --> 00:49:17.039
<v Speaker 2>atmosphere and highly sensitive spectrographs to track the exact Doppler

997
00:49:17.079 --> 00:49:20.440
<v Speaker 2>shifted infrared signature of hot hydrogen.

998
00:49:20.119 --> 00:49:22.639
<v Speaker 3>The stronomers were able to trace that fast moving river

999
00:49:22.760 --> 00:49:27.800
<v Speaker 3>backward through twenty six thousand light years of incredibly hostile.

1000
00:49:27.360 --> 00:49:30.599
<v Speaker 2>Space, and they found the definitive source, a pair of

1001
00:49:30.679 --> 00:49:34.239
<v Speaker 2>massive stars locked in a violent, high speed orbital embrace,

1002
00:49:34.679 --> 00:49:38.360
<v Speaker 2>violently crashing their stellar winds together like cosmic leaf blowers.

1003
00:49:38.000 --> 00:49:41.239
<v Speaker 3>Creating dense, glowing knots of gas that break off and

1004
00:49:41.280 --> 00:49:44.559
<v Speaker 3>feed our sleeping giant of a black hole one precise

1005
00:49:44.920 --> 00:49:46.679
<v Speaker 3>Earth sized meal every ten years.

1006
00:49:46.800 --> 00:49:50.159
<v Speaker 2>It is a remarkable testament to human curiosity, the scientific

1007
00:49:50.199 --> 00:49:53.800
<v Speaker 2>method and breath taking technological advancement that we, sitting on

1008
00:49:53.840 --> 00:49:56.079
<v Speaker 2>a small, rocky planet on the edge of the galaxy

1009
00:49:56.320 --> 00:49:59.320
<v Speaker 2>can piece together such a complex, invisible narrative taking place

1010
00:49:59.320 --> 00:50:02.480
<v Speaker 2>in the most extreme, dream highly obscured environment imaginable.

1011
00:50:02.599 --> 00:50:04.639
<v Speaker 3>It really is one of the greatest detective stories ever told.

1012
00:50:04.760 --> 00:50:07.599
<v Speaker 2>It absolutely is. But as with any good story, wrapping

1013
00:50:07.639 --> 00:50:09.639
<v Speaker 2>up this mystery just opens the door to another one.

1014
00:50:09.719 --> 00:50:11.559
<v Speaker 3>Always there's always another mystery.

1015
00:50:11.639 --> 00:50:14.280
<v Speaker 2>It leaves me with a final lingering question to ponder

1016
00:50:14.320 --> 00:50:17.840
<v Speaker 2>as we wrap up today. We establish that massive stars

1017
00:50:17.880 --> 00:50:21.960
<v Speaker 2>like the ones in IRS sixteen s W live incredibly volatile,

1018
00:50:22.159 --> 00:50:23.480
<v Speaker 2>furious lives.

1019
00:50:23.400 --> 00:50:25.840
<v Speaker 3>Yes, very short, very furious lives.

1020
00:50:26.000 --> 00:50:28.639
<v Speaker 2>Because they burn so hot and blow off so much mass,

1021
00:50:28.679 --> 00:50:32.199
<v Speaker 2>they burn through their nuclear fuel incredibly quickly compared to smaller,

1022
00:50:32.320 --> 00:50:35.199
<v Speaker 2>calmer stars like our Sun. They might only live for

1023
00:50:35.239 --> 00:50:36.360
<v Speaker 2>a few million years.

1024
00:50:36.519 --> 00:50:38.519
<v Speaker 3>A blink of an eye in cosmic terms.

1025
00:50:38.280 --> 00:50:42.199
<v Speaker 2>So, if this one specific contact binary star system is

1026
00:50:42.280 --> 00:50:45.880
<v Speaker 2>essentially operating as a slow drip I V solely responsible

1027
00:50:45.920 --> 00:50:49.559
<v Speaker 2>for keeping Sagittarius aphed and ticking right now, what happens

1028
00:50:49.599 --> 00:50:52.000
<v Speaker 2>to the center of our galaxy when that specific star

1029
00:50:52.039 --> 00:50:55.000
<v Speaker 2>system inevitably runs out of fuel and dies in a supernova?

1030
00:50:55.280 --> 00:50:56.679
<v Speaker 3>That is a million dollar question.

1031
00:50:56.760 --> 00:50:59.840
<v Speaker 2>Will that continuous river of gas dry up, Will our

1032
00:51:00.119 --> 00:51:03.920
<v Speaker 2>supermassive black hole finally go entirely hungry it's accretion dist

1033
00:51:03.960 --> 00:51:07.800
<v Speaker 2>emptying out falling completely utterly dormant and dark. Or is

1034
00:51:07.840 --> 00:51:10.880
<v Speaker 2>the dense, dusty heart of the Milky Way secretly filled

1035
00:51:10.920 --> 00:51:14.320
<v Speaker 2>with a whole hidden ecosystem of unseen, tightly wound leafblower

1036
00:51:14.360 --> 00:51:16.960
<v Speaker 2>binary stars just waiting in the wings to take its

1037
00:51:17.000 --> 00:51:18.719
<v Speaker 2>place and keep the cosmic engine running