The centre of the Milky Way is home to strange and deadly phenomena that are difficult to understand, but using the latest science, experts are revealing how the supermassive black hole at the galaxy's core shapes life on Earth.
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LearningTranscript
00:0026,000 late years from Earth, shrouded in cosmic dust and gas, is a mysterious region of space, the center of the Milky Way.
00:17The center of the Milky Way galaxy is one of the strangest, most exotic, and violent places in our galaxy.
00:29Gas streaming everywhere, radiation blasting out, stars moving willy-nilly.
00:37And at the very heart is the mysterious black hole, four million times the massive sunlight.
00:44Now, we're exploring the center of the Milky Way like never before, uncovering powerful forces that affect us all.
00:56Everything that happens at the center of the Milky Way galaxy really is connected to what's going on in the rest of the Milky Way.
01:02Understanding the center of our galaxy, unlock secrets of our past, present, and future.
01:11March, 2019.
01:30We focus the XMM-Newton Space Telescope on a region of space around Sagittarius A-Star, the supermassive black hole at the heart of our galaxy.
01:47We spot two huge columns of gas glowing in X-ray light.
02:00The columns seem to be coming from Sagittarius A-Star.
02:06We see giant fountains of gas extending outward from the central region as though it's like a wind or a giant expulsion event.
02:17The fountains of gas extend 500 light years above and below the supermassive black hole.
02:28That's over a million times the distance from the Sun to Neptune.
02:34It looks like this material is actually leaving the vicinity of the black hole, like it's burping out these giant hot X-ray chimneys.
02:44So why is Sagittarius A-Star burping out hot gas?
02:50Typically around a black hole, you have an accretion disk funneling material into the black hole, but all of it doesn't end up in the black hole.
02:57There is a little bit of gas falling onto it right now, even as I'm speaking, right?
03:04As gas falls towards the supermassive black hole, it becomes superheated, it liberates an enormous amount of energy, and that energy has to go somewhere.
03:14As gas spirals towards the black hole, some of the material accelerates to near the speed of light.
03:24It blasts out from the accretion disk, creating chimneys of superheated gas that seem to connect to two of the largest structures in the galaxy, the Milky Way's Fermi bubbles.
03:43A few years ago we noticed that in fact there are these giant bubbles coming out of the very heart of the Milky Way galaxy.
03:49In each direction, there's a bubble 25,000 light years long.
03:55But the gas-filled bubbles dwarf the chimneys of superheated gas.
04:00Scientists wonder if another, more powerful force blew the bubbles.
04:06So what could have created all of this superheated gas that actually blew these tremendously large bubbles?
04:12Supermassive black holes in other galaxies might offer clues.
04:17Black holes at the centers of galaxies go through different phases, so they can be either active or they can be calm.
04:23Sometimes black holes at the centers of galaxies go through an active phase.
04:29And when that happens, the black hole is actively feeding on material around it, which means it's growing, and it also gives off huge jets of radiation.
04:39Calm supermassive black holes release a trickle of hot gas.
04:46But when lots of material falls on them, they can shoot out jets up to millions of light years long.
04:58At the current time, Sagittarius A-star is what we call quiescent. It's quiet.
05:09There is some material swirling around it, but really not very much.
05:13But we don't think that's always been the case.
05:17The centers of galaxies are busy places. There are stars there, there's gas there, there's dust there.
05:26And sometimes these things fall into that black hole.
05:32Six million years ago, Sagittarius A-star may have had a feeding frenzy.
05:38Eating too much and blasting out the remains in huge jets.
05:45Those jets plow through the galaxy initially at near the speed of light.
05:53And as they do so, they can wreak havoc or sculpt the evolution of the galaxy that they're propagating through.
06:01Sagittarius A-star's jets blasted gas out of the galaxy, creating the scars we see as the Fermi bubbles.
06:13Now, whatever caused those jets seems to have turned off.
06:17It's not happening anymore. And we're seeing sort of the leftovers of them.
06:21But this is clearly a sign that sometime in the past few million years, the black hole in the center of our galaxy, Sagittarius A-star, was actively feeding on material around it.
06:32Material was falling into it and blasting out this stuff.
06:38The jets left destruction in their wake.
06:44They may have also affected the growth of our entire galaxy.
06:55These structures at the center of our galaxy are important because they can either shut off star formation or they can trigger star formation.
07:06As those jets propagate through the galaxy, they pile up gas.
07:10And that gas can be then triggered into star formation.
07:13But these jets can also impart so much heat or energy feedback into the environment that they prevent star formation.
07:27So black holes in many ways conduct an orchestra instructing or dictating when stars can and cannot form.
07:43In the center of the Milky Way, star formation rates seem low.
07:50The jets could be responsible.
07:54But in 2017, the ALMA telescope discovered the change is coming.
08:00So ALMA's actually been able to peer into the heart of our galaxy and see that near all this destruction, there might actually be a new generation of stars forming.
08:13Today, our calm supermassive black hole could be helping star formation in the core.
08:25But the Fermi bubbles could be evidence of a time when Sagittarius A-star shut down star formation.
08:32Could the supermassive black hole roar back to life in the future?
08:39Sag A-star could roar back to life by just dumping some gas onto it.
08:43And there's a lot of gas at the center of our galaxy and it could wander into the proximity of Sagittarius A-star and ultimately fall onto the event horizon.
08:50And that would light it up.
08:58If Sagittarius A-star eats enough gas, it could shut down star formation in the galaxy for millions of years.
09:09It could also give off X-rays and gamma rays that may hit the Earth.
09:24Thankfully, our central supermassive black hole is pretty quiet and massive feeding events, massive energy events are very, very rare.
09:34We don't necessarily have much to worry about.
09:41Sagittarius A-star has reshaped our galaxy.
09:49If we want to survive in the universe, we need to know more about this monster black hole.
09:57The Event Horizon Telescope is on a mission to do just that.
10:01Question is, can it succeed?
10:17The center of the Milky Way is home to a supermassive black hole, Sagittarius A-star.
10:24At least, we think it is.
10:26We've never seen the supermassive black hole directly, but we have seen stars racing around the core.
10:36The speeds of the stars zipping around the center of our Milky Way galaxy indicate that there's something very massive and very compact there.
10:46Indeed, four million times as massive as our sun in a volume smaller than that of our solar system.
10:56It's got to be a black hole, basically.
10:59By measuring the orbits of stars in our galaxy's center,
11:03We estimate that Sagittarius A-star is over a hundred times wider than our sun.
11:16But despite its size, the black hole is hidden.
11:19One of the immediate challenges of actually observing black holes is the fact that they don't emit light, and so you can't see them.
11:29Right?
11:30So we've never actually seen a black hole.
11:31We've only seen the stuff around a black hole.
11:34Or we have seen the effects that that black hole imparts on its ambient surroundings.
11:38That's where the Event Horizon Telescope came in.
11:44Its goal was to photograph Sagittarius A-star.
11:49Not the black hole itself, but its shadow.
11:54A roundup is this gas that is moving around the black hole that's superheated to millions of degrees.
12:00And what the Event Horizon Telescope is trying to see is the shadow of the black hole.
12:04Light from the hot gas around Sagittarius A-star frames the giant shadow.
12:12It could be up to 93 million miles across.
12:17Problem is, Sagittarius A-star is so far away that the supermassive black hole is still incredibly hard to see.
12:27Sagittarius A-star is big, but it's 26,000 light years away.
12:31A single light year is 6 trillion miles.
12:35So this is a long, long walk.
12:38And even though it's big, that distance shrinks its apparent size to just a tiny little dot on the sky.
12:44To see the tiny dot, we need a telescope the size of the Earth.
12:49How do you possibly do that? You can't build that telescope, right?
12:55Well, there's a trick. You actually get a few different telescopes and you spread them out over the surface of the Earth.
13:02And when we add all of these sites together, we wind up being able to take an image of something that is really, really impossibly small.
13:16To gather enough light to see a target this small, the team take long exposure images of Sagittarius A-star's shadow.
13:31But there's a problem.
13:35The accretion disk moves too much for us to capture a clear image.
13:42When you're taking a long exposure of a person, you need them to be really, really still.
13:48Because if they're moving around a lot, they're going to blur the image out.
13:51And that kind of thing is happening when we observe Sagittarius A-star because it is unwilling to sit still for us.
13:57It is booming and banging and flashing on the timescale of literally hours.
14:03As glowing material orbits the black hole at 30% the speed of light, Sagittarius A-star's shadow blurs.
14:14Future developments may allow us to see Sagittarius A-star clearly.
14:21For now, we can't capture an accurate image of our galaxy's supermassive black hole.
14:30But the hunt to see a supermassive black hole wasn't over.
14:35The Event Horizon Telescope turned to another galaxy 54 million light years away, M87.
14:45M87 is an absolute beast of a galaxy.
14:48It's a so-called brightest cluster galaxy.
14:50These are among the largest galaxies in the universe.
14:55And M87 is home to another supermassive black hole, the giant M87 star.
15:05M87 star is so massive that the gravitational region that's interesting is actually easier to image than the black hole in our own galaxy.
15:14M87 star is over a thousand times more massive than Sagittarius A-star and has a far larger accretion disk.
15:26When photographing a black hole, size matters because big accretion disks project more stable light, so images of them don't blur as much.
15:38In April of 2019, the Event Horizon team unveiled their image.
15:50We've seen what we thought was unseeable.
15:53We have seen and taken a picture of a black hole.
15:56I've been working on this project for almost six years now, and so this is something we've been looking forward to for a really long time.
16:11Capturing this image took decades of work by hundreds of scientists all over the world.
16:18I was really stunned.
16:25Suddenly when you say that's the real thing, that's amazing.
16:29It really affected me.
16:31This is something six and a half billion times the mass of the sun, 55 million light years away, and we're looking at it?
16:40So when you look at the image, it's totally fine, you're totally forgiven for thinking, eh, it looks a little blurry.
16:48But I cannot reiterate enough how profound this image actually is.
16:54We are seeing just a hair's width away from a discontinuity in the fabric of space-time itself.
17:01Actually seeing so close to an actual event horizon, a discontinuity in the fabric of space-time never seemed possible.
17:09This image of the heart of a distant galaxy helps us understand supermassive black holes like never before.
17:19When we observe supermassive black holes in other galaxies, including the one in M87,
17:26we're able to learn more about the big picture of how these massive black holes form and evolve over time.
17:32And that in turn helps us understand how our Milky Way galaxy and its supermassive black hole has formed.
17:38By studying, not just making images of black holes, but making videos of black holes and seeing as that gas is spinning around it,
17:48we can try to map around a black hole more precisely and learn about its dynamics.
17:53An image of Sagittarius A-Star remains out of reach, but in 2018, it shows a deadly side to its character.
18:05The supermassive black hole's accretion disk releases huge, powerful flares, and they could be pointed right at us.
18:15In 2018, astronomers were studying a special star orbiting our galaxy's supermassive black hole.
18:29The star passes close to Sagittarius A-Star every 16 years.
18:34It's called S-2, and by studying this star's flyby, we hope to learn more about Sagittarius A-Star.
18:45We think that S-2 may be the very closest star to the supermassive black hole in the center of our galaxy.
18:51At closest approach to Sag A-Star, S-2 comes within 17 light hours or so of the surface.
18:58The supermassive black hole's powerful gravity accelerates the star to 17 million miles an hour.
19:08That's fast enough to travel from New York to L.A. in half a second.
19:13But it's not the star's speed that excites scientists.
19:19This is a great star because it's on an elliptical orbit that takes it fairly far from the black hole,
19:25but every few years it passes right above the supermassive black hole.
19:32As we tracked S-2's swing around Sagittarius A-Star,
19:36we detected powerful bursts of infrared light coming from the direction of the supermassive black hole.
19:46There's a blob of gas that is orbiting very close to the black hole, and it was flaring as it went around.
19:53There were three separate flares of light that they were able to detect.
19:59The flares didn't come directly from the supermassive black hole.
20:04They came from the material around it.
20:10The flares that were discovered are thought to originate from magnetic storms
20:14and this very, very hot, turbulent gas around the black hole.
20:21The extreme heat in the accretion disk strips electrons from atoms of gas.
20:26The stripped electrons and hot gas form a plasma,
20:30which creates powerful magnetic fields when accelerated to high speeds.
20:35Because some supermassive black holes have these superheated, rapidly spinning vortices of gas swirling around them,
20:44you get these very, very powerful, very tightly wound magnetic fields.
20:50And there's energy stored in that magnetic field.
20:53It's like a bunch of piano wires all tangled up.
20:55And if these things interact with each other, they can snap.
20:58And when they snap, that energy is released.
21:05You get this enormous release of energy as these coils of magnetic fields effectively snap.
21:11And when they do so, just like on the surface of our sun, they release an enormous flare of gas.
21:18These powerful flares can be millions of miles wide
21:27and come packed with superheated gas and plasma.
21:35Solar flares release as much energy as 10 million volcanic explosions.
21:40Flares from Sagittarius A-STAR's accretion disk
21:50are like millions of solar flares, all going off at once.
21:59It's kind of like comparing a nuclear weapon to a firecracker.
22:04Sagittarius A-STAR's flares release intense blasts of radiation,
22:09but by watching the flares from Earth,
22:12we can learn about the orientation of the supermassive black hole's accretion disk.
22:20This gas that's in this accretion disk around the black hole
22:23is like a friendly helper shining a flashlight back toward Earth.
22:28And we can watch the orbit of these flashlights
22:30and help understand the orientation of gas that swirls around the black hole.
22:34We think we're getting a bird's eye view of it and looking down the barrel
22:40or looking at the accretion disk basically face on.
22:44That means that any material that gets blasted away from the black hole could be aimed right at us.
22:50Should we be worried about the flares reaching Earth?
22:57It sounds worrisome, this blob of gas emitting these huge flares of light.
23:03But you've got to realize, this is 26,000 light years away.
23:07That is a long way.
23:08It took an extremely sensitive detector on one of the largest telescopes on Earth
23:13to be able to see this at all.
23:16Earth is safe, for now.
23:19But the more we learn about the galaxy's center, the more terrifying it becomes.
23:24We know of Sagittarius A-star, the central supermassive black hole,
23:29but now we're beginning to suspect that it might not be alone.
23:34A dangerous swarm of black holes could be racing around the center of the Milky Way.
23:41Thousands more may be hiding from sight.
23:44The supermassive black hole, Sagittarius A-star, dominates the center of the Milky Way.
24:02Affecting star formation,
24:06and carving out vast gas bubbles in space.
24:09But Sagittarius A-star might not be the only black hole in town, or even the most dangerous.
24:22We've known for a long time that there's a supermassive black hole in the very heart of our galaxy.
24:27But there may be an angry swarm of smaller black holes buzzing all around it.
24:32In April of 2018, astronomers led by Columbia University
24:37revealed the results of a hunting mission in the center of the galaxy.
24:42They'd used 12 years of Chandra Observatory data to seek out stellar mass black holes.
24:50Black holes that are made from the death of stars from supernova explosions
24:54are called stellar mass black holes.
24:56And these are made from stars that were many times the mass of the sun.
25:07Finding stellar mass black holes is tough.
25:13Light can't escape a black hole's gravity, so we can't see them directly.
25:18And stellar mass black holes are only tens of miles wide, making them almost impossible to detect.
25:30So astronomers look for a special type of stellar mass black hole.
25:36One of the ways that we look for stellar mass black holes is that they often are vampires eating a companion star.
25:49These vampires are part of a binary pair.
25:57A stellar mass black hole in orbit with a living star.
26:03The black hole feasting on its partner.
26:05That black hole is like a very, very deadly parasite for that star.
26:11It is ripping mass off the surface of that star.
26:14And that matter is raining down toward the black hole itself.
26:20And that material lights up.
26:23So this allows us to hunt for black holes, not through taking pictures of black holes directly,
26:28but through seeing the material falling to its doom.
26:34Problem is, gas and dust spread throughout the galaxy stops visible light from the binary pair reaching Earth.
26:42But the binary pair release another type of light that passes through the gas and dust more easily.
26:49X-rays.
26:51The system itself is emitting X-rays, so they're called X-ray binaries.
26:55So these are useful because the X-ray emission can be very powerful and can be potentially seen from the Earth,
27:02even though the binary is very far away, say at the galactic center.
27:09The glowing disks of material in X-ray binary systems are almost a million times smaller than the accretion disk surrounding Sagittarius A-star.
27:19Too small for us to see the material swirling around them in detail.
27:23So, we see the X-ray binaries as pinpricks of X-ray light.
27:33Astronomers detect 12 of these X-ray binaries in a small, three-light-year-wide patch of space at the galactic center.
27:42And that means that there could be a much larger collection of these relatively tiny stellar-mass black holes in the heart of our galaxy.
27:49If black holes form the way we think they do, there very likely may be swarms of black holes racing around Sagittarius A-star.
27:59But X-ray binaries that are powerful enough for us to detect are incredibly rare.
28:06So, we estimate that for the dozen X-ray binaries discovered, there could be up to a thousand more.
28:15In total, there could be 20,000 stellar-mass black holes in this three-light-year region of space.
28:28Why are these black holes swarming in the galaxy's center?
28:42It appears they've migrated from the rest of the Milky Way.
28:45Through a process called dynamical friction, black holes can actually sink to the centers of galaxies very, very rapidly, like dropping a stone into a pond.
28:56What that means is that an errant, wandering black hole might eventually find its way toward the center of our own galaxy, where Sagittarius A-star resides.
29:04As stellar-mass black holes orbit the galaxy, they interact gravitationally with stars and clouds of gas and dust.
29:16These interactions push the black holes towards the center of the galaxy, where the black holes swarm.
29:25A swarm of stellar-mass black holes sounds deadly, but it may not be the most lethal thing in the center of the Milky Way.
29:39A surprising observation indicates that there is a lot of antimatter in the center of our galaxy.
29:47And when antimatter meets matter, the results are explosive.
30:06In 2017, astronomers tried to solve a decades-old cosmic mystery.
30:11Unexplained, high-energy radiation streaming through our galaxy.
30:24At first, we didn't know where it was from.
30:29But we discovered it was gamma radiation coming from somewhere in the center of the Milky Way.
30:38The question is, what's making these gamma rays?
30:40That's hard to do.
30:42It's not like you can rub your hands together and generate gamma rays.
30:47When we took a closer look at the gamma rays, we discovered the signature of the most explosive substance in the universe.
30:54Antimatter.
31:00Antimatter is like normal matter, but with opposite charge.
31:05That's it. It's matter's evil twin.
31:07When evil twin meets good twin, it is not a happy reunion.
31:14Antimatter is scary. It's not like you want to have some in your kitchen.
31:21This stuff is very, very explosive if you want to think of it that way.
31:25If it touches normal matter, it releases a huge amount of energy.
31:32When matter and antimatter combine, they annihilate each other and transform into high-energy radiation, just like the gamma rays seen streaming out of the center of the Milky Way.
31:42We see antimatter throughout the galaxy, but strangely, the galactic center seemed to have 40% more antimatter than anywhere else.
31:55Right now in the heart of our galaxy, we actually observe fountains of antimatter that are producing 10 trillion tons of antimatter every second.
32:06One of the big questions that we've wondered about for a very long time is, what's the origin of this stuff?
32:16Initially, there were several suspects.
32:18One possible source of antimatter is the central supermassive black hole, Sagittarius A-star.
32:25Matter can be swirling around this and it can have such high energy that it can create antimatter.
32:33But the antimatter isn't coming from a single point.
32:37It's spread across thousands of light years of space.
32:40So Sagittarius A-star can't be the source of the gamma ray stream.
32:50Another suspect was dark matter.
32:55One of the biggest mysteries in the universe right now is dark matter.
32:59We know that the majority of mass in the universe is not in the same form that we are.
33:03It's not made of atoms.
33:04But whatever sort of particle it is or may be, if these things collide, they can produce antimatter.
33:11And that will produce the gamma rays.
33:13So it's possible that as we look into the heart of the galaxy and see these extra gamma rays,
33:17that's the signal that dark matter is there.
33:24But the gamma ray stream we detected is too weak to have been created by dark matter.
33:29Then, we had a breakthrough.
33:36We discovered that a special metal called titanium-44 could be responsible for the gamma ray stream.
33:48Titanium-44 is a highly radioactive element.
33:51That means that it wants to decay into other types of nuclei.
33:54When titanium-44 decays, it gives off antimatter.
34:01But to produce the antimatter seen in the galaxy's core, you would need a lot of titanium-44.
34:09It could be created in rare energetic events.
34:13In the collision of two dead stars, white dwarves.
34:18A white dwarf star is a star that didn't have enough mass when it died to actually become a supernova.
34:26It just sort of cools off as a dead little cinder.
34:29But what if you have two white dwarves that are orbiting around each other?
34:32And as they come closer and closer and collide, all of a sudden now you have enough mass to actually kick a supernova explosion off.
34:38These particular kinds of supernovae are very good at producing titanium-44.
34:49So these kinds of supernovas are very, very good at making antimatter.
34:54These supernovas erupt in the core of the galaxy once every 2,000 years.
35:06But outside of the core, in the disk of the galaxy where our solar system orbits,
35:12these supernovas happen three times as often.
35:16So the gamma ray observations were wrong.
35:22There isn't more antimatter in the heart of the galaxy.
35:26It's our region of the galaxy that contains the most antimatter.
35:31The question is, are we in danger?
35:36If you take an ounce of matter and an ounce of antimatter and collide them,
35:42you're generating a megaton of energy.
35:44The equivalent of a million tons of TNT exploding.
35:49So you don't need much antimatter to generate a vast amount of energy.
35:54But the thing you have to remember is we live in this wonderful, dramatic environment of a larger universe.
36:01It's not dangerous. It's very far away from us.
36:04And it's fascinating that all of this antimatter is being produced in our galaxy.
36:09So just sit back and enjoy the fireworks.
36:13The center of the Milky Way is violent and extreme.
36:19But things could get a whole lot worse.
36:23Rogue, supermassive black holes could be lurking near our galaxy.
36:28And they have the power to end life as we know it.
36:33The Milky Way is around 100,000 light years across.
36:37And it's home to at least 200 billion stars.
36:41But it hasn't always been this large.
36:42We know that our Milky Way galaxy grew to the size it is now, which is huge, by eating other galaxies.
36:51And some of these galaxies would have had supermassive black holes in their centers.
36:59When the Milky Way's gravity pulled in smaller galaxies, most of their material merged into the Milky Way.
37:05And some of these galaxies would have had supermassive black holes in their centers.
37:09When the Milky Way's gravity pulled in smaller galaxies, most of their material merged with the Milky Way.
37:23But some material, like stars, could have been slung tens of thousands of light years out of the Milky Way.
37:30This could have happened to a smaller galaxy's supermassive black hole.
37:40It is entirely possible there are supermassive black holes wandering around out there, not in the center.
37:49So how could it be possible that there's actually a supermassive black hole close to us wandering around, but we never even see it?
37:56Well, remember, black hole means it's really, really black.
37:59It actually absorbs radiation in any energy.
38:02So unless something is falling into a black hole or orbiting around it, you're not going to see it.
38:08And so if this supermassive black hole were hypothetically wandering the outskirts of our galaxy,
38:14well, there's a lot less gas there for that black hole to run into.
38:17And if there's no gas around that black hole, we will not see it.
38:23The rogue supermassive black hole may not stay in the outskirts of the galaxy forever.
38:29Gravitational interactions slowly pull it back into the Milky Way.
38:35Billions of years later, the supermassive black hole could arrive in the center.
38:41When this rogue supermassive black hole meets up with Sagittarius A-Star, the fuse is lit.
38:53The pair spiral towards each other, spinning faster and faster, reaching up to half the speed of light.
39:05Finally, the two black holes merge.
39:08You would have an enormously energetic event on your hands.
39:23Those supermassive black holes could, in principle, merge together, create a huge blast of gravitational waves,
39:30accompanied by a profoundly energetic flash of light that could, in principle, endanger all life on Earth.
39:36It's literally a stretching and contracting of space itself.
39:48It's like grabbing the framework of space and it's shaking it really hard.
39:52And if this happens in our galaxy, the amount of energy emitted, that would be bad.
39:58When the black holes collide, they release more energy than all the stars in the galaxy combined.
40:11Should we be panicked about this? And the answer is no.
40:20The Earth has been orbiting the Sun for four and a half billion years without any incident, right?
40:24We're pretty safe from them.
40:27If we were around to see the two black holes collide,
40:31we'd witness the most destructive light show in the history of the galaxy.
40:35But, for now, the center of our galaxy is relatively quiet.
40:44But it's still a terrible place to be.
40:50The center of our Milky Way is not a friendly place.
40:54It's nowhere you want to be. It's a bad neighborhood.
40:58You've got tons of stars, tons of radiation.
41:01The stars are being born and dying and exploding.
41:05You've got the central supermassive black hole.
41:07You've got a potential swarm of black holes.
41:10You've got accretion disks.
41:11You've got flares.
41:12You've got magnetic outbursts.
41:14You've got jets.
41:16Let's just stay out here in the suburbs, alright?
41:21The center of our galaxy is one of the most nightmarish places in the cosmos.
41:25It's also home to some of the most incredible forces the universe has to offer.
41:34Whatever the future holds for our galaxy,
41:40the core of the Milky Way will be at the center of it all.
41:45Our home galaxy, the Milky Way, is our safe harbor, our island in this vast cosmic ocean.
41:54And so to understand the heart of our galaxy is to understand our home in this cosmic void.
41:59We're home in this cosmic void.