WEBVTT 1 00:00:03.399 --> 00:00:07.719 Welcome to Bedtime Astronomy. Explore the wonders of the cosmos 2 00:00:07.759 --> 00:00:12.279 with our soothing Bedtime Astronomi podcast. Each episode offers a 3 00:00:12.359 --> 00:00:16.320 gentle journey through the stars, planets, and beyond, perfect for 4 00:00:16.399 --> 00:00:20.239 unwinding after a long day. Let's travel through the mysteries 5 00:00:20.239 --> 00:00:22.440 of the universe as you drift off into a peaceful 6 00:00:22.480 --> 00:00:23.800 slumber under the night sky. 7 00:00:26.960 --> 00:00:31.839 Imagine looking into a kindergarten classroom. You'd expect to see 8 00:00:31.879 --> 00:00:36.000 you four year olds playing with blocks, figuring out basic shapes, 9 00:00:36.079 --> 00:00:36.600 just sort. 10 00:00:36.439 --> 00:00:38.520 Of napping, spilling juice. 11 00:00:38.240 --> 00:00:41.759 Right exactly, just starting to piece the world together. But instead, 12 00:00:42.079 --> 00:00:44.880 sitting right there in one of those tiny plastic chairs 13 00:00:45.399 --> 00:00:47.799 is a fully grown, fifty. 14 00:00:47.520 --> 00:00:49.880 Year old adult wearing a tailored suit. 15 00:00:49.719 --> 00:00:52.719 Wearing a tailored suit, doing complex calculator. I mean, it 16 00:00:52.759 --> 00:00:56.880 makes absolute no sense, right, The timeline is just completely broken. 17 00:00:57.079 --> 00:00:59.280 Yeah, that adult simply hasn't had the time to. 18 00:00:59.200 --> 00:01:02.240 Grow up in that exactly, and that feeling of just 19 00:01:02.679 --> 00:01:08.719 complete paradigm breaking confusion. That is exactly what astrophysicists experienced recently. 20 00:01:08.799 --> 00:01:12.000 Oh absolutely, when the James Webb Space Telescope stared into 21 00:01:12.040 --> 00:01:15.040 the deepest, oldest reaches of the universe. 22 00:01:15.280 --> 00:01:19.120 It is honestly the ultimate cosmic anachronism. Yeah, we're looking 23 00:01:19.200 --> 00:01:22.840 at a stage in the universe's history where everything should 24 00:01:22.840 --> 00:01:25.840 be in its infancy, right, you know, small gas clouds, 25 00:01:25.879 --> 00:01:30.560 the very first rudimentary star is just just beginning to ignite, 26 00:01:30.879 --> 00:01:34.840 small structures starting to merge together. Babies, just babies. Yeah, 27 00:01:35.000 --> 00:01:38.040 But sitting right there in the middle of this cosmic 28 00:01:38.120 --> 00:01:43.400 kindergarten is an absolute monster, a super massive black hole. 29 00:01:43.519 --> 00:01:46.599 It's wild. And to really understand why this discovery is 30 00:01:46.680 --> 00:01:49.439 keeping cosmologists awake at night, we kind of have to 31 00:01:49.480 --> 00:01:50.599 look at the classical. 32 00:01:50.280 --> 00:01:52.840 Rules of the universe, right, the established playbook. 33 00:01:52.560 --> 00:01:56.040 Right, because the model we've all accepted for decades, it's 34 00:01:56.079 --> 00:01:59.599 built on a very simple, very logical sequence of events 35 00:02:00.040 --> 00:02:02.519 starts small. You have to right in the beginning, you 36 00:02:02.560 --> 00:02:05.719 have giant clouds of gas. Gravity pulls that gas together 37 00:02:05.799 --> 00:02:08.479 until it ignites, and boom, you get a star. 38 00:02:08.479 --> 00:02:12.360 Right, And a massive star burns, furiously runs out of 39 00:02:12.479 --> 00:02:16.240 nuclear fuel, and eventually, well, it collapses under its own 40 00:02:16.240 --> 00:02:17.120 immense weight, and. 41 00:02:17.080 --> 00:02:19.800 That collapse creates a stellar mass black. 42 00:02:19.520 --> 00:02:22.479 Hole right exactly, the dead remnant of a single star. 43 00:02:22.479 --> 00:02:25.680 Just a small baby black hole. And from there, the 44 00:02:25.680 --> 00:02:28.520 classical model says, this little black hole starts to feed. 45 00:02:28.879 --> 00:02:31.680 It pulls in surrounding gas as well as rogue planets. 46 00:02:32.639 --> 00:02:35.080 Maybe it merges with another small black hole in nearby. 47 00:02:35.319 --> 00:02:37.000 It's a slow process of accretion. 48 00:02:36.879 --> 00:02:41.039 Accretion, right. But here's the critical part for you listening. 49 00:02:41.879 --> 00:02:44.919 There is a hard physical speed limit on how fast 50 00:02:44.960 --> 00:02:46.960 a black hole can actually eat, isn't there? 51 00:02:47.120 --> 00:02:50.639 Yes, the Eddington limit. And this is a crucial piece 52 00:02:50.719 --> 00:02:54.000 of the physics puzzle that makes this new discovery just 53 00:02:54.120 --> 00:02:55.520 so baffling. 54 00:02:55.199 --> 00:02:56.159 Like that down for us. 55 00:02:56.439 --> 00:02:59.240 So, when gas falls into a black hole, it doesn't 56 00:02:59.280 --> 00:03:02.120 just drop straight in. It swirls around, you know, like 57 00:03:02.240 --> 00:03:03.639 water circling a drain. 58 00:03:03.560 --> 00:03:05.960 Right, forming that accretion disk exactly. 59 00:03:06.560 --> 00:03:09.039 And as all that material rubs together, it do the 60 00:03:09.080 --> 00:03:11.960 speed of light. The friction heats the gas up to 61 00:03:12.039 --> 00:03:15.120 millions of degrees oh wow. Yeah, and that causes it 62 00:03:15.159 --> 00:03:19.080 to emit massive amounts of radiation, just blinding light and heat. 63 00:03:19.240 --> 00:03:22.400 And that radiation pushes outward, doesn't it Precisely, The outward 64 00:03:22.400 --> 00:03:25.039 pressure of the radiation pushes against the inward pull. 65 00:03:24.879 --> 00:03:25.919 Of the black hole's gravity. 66 00:03:26.000 --> 00:03:27.719 It's a tug of war exactly. 67 00:03:27.960 --> 00:03:29.840 So if a black hole tries to eat too much 68 00:03:30.000 --> 00:03:33.599 too fast, the radiation pressure becomes so intense that it 69 00:03:33.599 --> 00:03:35.280 actually blows the surrounding food away. 70 00:03:35.360 --> 00:03:36.599 Wait, so it stars itself. 71 00:03:36.879 --> 00:03:40.599 It starves itself. So because of this Eddington limit, a 72 00:03:40.639 --> 00:03:44.479 black hole can only grow at a strictly regulated, very 73 00:03:44.520 --> 00:03:45.240 incremental pace. 74 00:03:45.360 --> 00:03:47.719 Okay, So to go from a single dead star to 75 00:03:48.199 --> 00:03:51.280 a super massive black hole with the mass of millions 76 00:03:51.319 --> 00:03:52.159 of suns. 77 00:03:52.159 --> 00:03:55.479 You need billions of years of slow, steady. 78 00:03:55.120 --> 00:03:58.840 Feeding billions, which means the galaxy, you know, the stars, 79 00:03:58.879 --> 00:04:01.159 the gas, the whole food source has to exist first. 80 00:04:01.360 --> 00:04:06.000 Right, the stars are the bricks. You need generations of them, living, dying, 81 00:04:06.120 --> 00:04:09.919 and feeding the center to slowly build this supermassive skyscraper. 82 00:04:10.039 --> 00:04:13.120 But the James Web Space Telescope just found a skyscraper 83 00:04:13.159 --> 00:04:16.000 that exists before the bricks were ever even manufactured. 84 00:04:16.199 --> 00:04:18.800 Yeah, it's it's mind bending. The object we are looking 85 00:04:18.839 --> 00:04:22.560 at is officially cataloged as a bell two seven four 86 00:04:22.639 --> 00:04:23.680 four QSO one. 87 00:04:23.879 --> 00:04:26.439 Okay, let's pause on that name for a second. QSO one. 88 00:04:26.519 --> 00:04:29.519 I know astronomers love their acronyms, but what does QSO 89 00:04:29.600 --> 00:04:31.720 actually stand for? And like, why does it matter here? 90 00:04:31.800 --> 00:04:31.920 Right? 91 00:04:31.959 --> 00:04:34.920 So, QSO stands for quasi stellar object, which is the 92 00:04:34.959 --> 00:04:38.120 formal term for what we more commonly call a quasar moiser. Yeah, 93 00:04:38.360 --> 00:04:41.279 when astronomers first discovered these things back in the mid 94 00:04:41.319 --> 00:04:44.639 twentieth century, they looked through their telescopes and saw what 95 00:04:44.759 --> 00:04:48.600 looked like ordinary single stars, just a little pin pricks 96 00:04:48.639 --> 00:04:52.199 of light exactly. But when they analyzed the light, the 97 00:04:52.319 --> 00:04:56.000 energy output was impossibly high for a single star, so 98 00:04:56.040 --> 00:04:58.040 they called them quasi stellar. 99 00:04:57.879 --> 00:04:59.920 Quasi stellar, so they weren't stars. 100 00:04:59.639 --> 00:05:02.279 At all, not at all. It took years to realize 101 00:05:02.279 --> 00:05:05.360 that these were actually the intensely glowing accretion disks of 102 00:05:05.439 --> 00:05:07.079 supermassive black hole at. 103 00:05:06.959 --> 00:05:08.800 The centers of distant galaxies. 104 00:05:09.000 --> 00:05:12.720 Yes, feeding so voraciously that they outshine the hundreds of 105 00:05:12.759 --> 00:05:15.040 billions of stars in their host galaxy combined. 106 00:05:15.120 --> 00:05:17.720 That is just terriff. So when we talk about QSO one, 107 00:05:17.759 --> 00:05:22.519 we are talking about an actively feeding, brilliantly bright black hole, right. 108 00:05:22.879 --> 00:05:25.439 And it's often referred to in the research as little 109 00:05:25.439 --> 00:05:25.839 red dot. 110 00:05:25.920 --> 00:05:29.279 Little red dot, which sounds cute but perfectly describes how 111 00:05:29.279 --> 00:05:31.639 it appears on the James Web imaging sensors. 112 00:05:31.920 --> 00:05:35.680 It does, But that simple visual description really belies an 113 00:05:35.720 --> 00:05:36.959 astonishing reality. 114 00:05:37.240 --> 00:05:40.040 Yeah, let's look at the timeline. QSO one existed just 115 00:05:40.120 --> 00:05:43.879 seven hundred million years after the Big Bang. Now, if 116 00:05:43.879 --> 00:05:46.079 you're listening to this, you probably know the universe is 117 00:05:46.199 --> 00:05:50.519 roughly thirteen point eight billion years old, give or take. Yeah, 118 00:05:50.519 --> 00:05:53.040 so let's map that onto a human life span to 119 00:05:53.079 --> 00:05:55.759 make it visceral. If the universe is an eighty year 120 00:05:55.800 --> 00:05:59.319 old person today, we are looking at a snapshot from 121 00:05:59.360 --> 00:06:02.319 when that person was just four years old, a toddler, 122 00:06:02.399 --> 00:06:05.959 a toddler, and at that toddler stage, the light from 123 00:06:06.040 --> 00:06:08.040 this object began its journey. 124 00:06:08.120 --> 00:06:10.839 Right. It has been traveling through the expanding vacuum of 125 00:06:10.839 --> 00:06:14.639 space for over thirteen billion years just to hit the 126 00:06:14.680 --> 00:06:15.680 golden mirrors of our. 127 00:06:15.600 --> 00:06:17.600 Telescope, which is crazy to think about. 128 00:06:17.759 --> 00:06:21.199 And because the universe is expanding, the space between us 129 00:06:21.240 --> 00:06:24.680 and QSO one has been literally stretching the entire time 130 00:06:24.720 --> 00:06:25.199 that light. 131 00:06:25.120 --> 00:06:27.040 Was in transit, right, which is exactly why we need 132 00:06:27.120 --> 00:06:29.160 James Webb in the first place. Isn't it like Hubble 133 00:06:29.160 --> 00:06:30.040 couldn't have spotted this? 134 00:06:30.240 --> 00:06:34.759 No, Hubble is an incredibly powerful optical and ultra violet telescope. Yeah, 135 00:06:34.920 --> 00:06:37.839 but think about what happens when you stretch a light wave, 136 00:06:37.959 --> 00:06:42.639 it changes color exactly as the universe expands. It grabs 137 00:06:42.680 --> 00:06:46.600 the visible light emitted by QSO one thirteen billion years ago, 138 00:06:46.920 --> 00:06:48.720 and stretches the wavelength. 139 00:06:48.360 --> 00:06:50.680 So by the time it reaches us, that wave. 140 00:06:50.439 --> 00:06:53.279 Has been stretched out of the visible spectrum entirely and 141 00:06:53.360 --> 00:06:56.879 into the infrared. It's called cosmological red shift. 142 00:06:56.639 --> 00:07:00.639 Redshift, so the light literally becomes redder and then completely invisible. 143 00:07:00.639 --> 00:07:02.040 To humanize, right, and. 144 00:07:02.079 --> 00:07:06.319 James Web was specifically engineered with near infrared and mid 145 00:07:06.319 --> 00:07:11.040 infrared sensors to capture this exact kind of ancient stretched light. 146 00:07:11.240 --> 00:07:14.079 Okay, so Web spots this infrared little red dot. But 147 00:07:14.279 --> 00:07:16.639 the physical size of this thing is what really caught 148 00:07:16.639 --> 00:07:17.120 my attention. 149 00:07:17.199 --> 00:07:17.800 Oh it's tiny. 150 00:07:17.839 --> 00:07:20.600 It's only thirteen hundred light years across for anyone trying 151 00:07:20.600 --> 00:07:23.000 to visualize that. You know, our own Milky Way galaxy 152 00:07:23.120 --> 00:07:25.959 is about one hundred thousand light years from edge to edge. Right, so, 153 00:07:26.040 --> 00:07:29.439 QSO one is barely more than one percent the size 154 00:07:29.480 --> 00:07:30.160 of our galaxy. 155 00:07:30.240 --> 00:07:31.399 It is incredibly compact. 156 00:07:31.480 --> 00:07:33.319 But wait, if you're listening to this and running the 157 00:07:33.360 --> 00:07:35.720 mental math, a massive red flag should be going up 158 00:07:35.800 --> 00:07:38.319 right now. It should because if something is only thirteen 159 00:07:38.399 --> 00:07:40.959 hundred light years wide and it is located thirteen billion 160 00:07:41.040 --> 00:07:43.759 light years away. Yeah, it shouldn't just be a dot. No, 161 00:07:44.079 --> 00:07:46.839 it should be sub microscopic. I mean it should be 162 00:07:47.040 --> 00:07:50.920 entirely invisible even to James web The resolution required to 163 00:07:50.959 --> 00:07:54.480 see any internal structure of an object that small at 164 00:07:54.480 --> 00:07:58.120 that distance, it borders on science fiction, it really does. 165 00:07:58.199 --> 00:08:01.360 How are we not just seeing a single blurry pixel. 166 00:08:01.680 --> 00:08:04.920 Well, that skepticism is entirely warranted. I mean, if we 167 00:08:04.920 --> 00:08:07.160 were just pointing James Webb in an empty patch of 168 00:08:07.160 --> 00:08:09.720 space and zooming in, we would not be able to 169 00:08:09.720 --> 00:08:12.040 resolve the details of QSO one. 170 00:08:12.279 --> 00:08:13.680 The optics just wouldn't allow it. 171 00:08:13.720 --> 00:08:16.480 The geometry of the optics simply wouldn't allow it. Yeah, 172 00:08:16.560 --> 00:08:18.800 we're only able to study this object because we had 173 00:08:18.839 --> 00:08:22.560 help from one of the most bizarre and powerful phenomenon. 174 00:08:22.040 --> 00:08:23.519 Physics, gravitational lensing. 175 00:08:23.759 --> 00:08:27.040 Exactly in this case, Nature provided us with a giant 176 00:08:27.079 --> 00:08:31.319 magnifying glass called ABLE twenty seven forty four, also known 177 00:08:31.319 --> 00:08:32.600 as Pandora's. 178 00:08:32.039 --> 00:08:34.679 Cluster Caandora's cluster. It's like a massive pile up of 179 00:08:34.759 --> 00:08:38.600 multiple galaxy clusters. But how does a cluster of galaxies 180 00:08:38.639 --> 00:08:41.799 act as a magnifying glass. We're obviously not talking about 181 00:08:41.840 --> 00:08:42.840 glass lenses here. 182 00:08:43.000 --> 00:08:45.559 No, we have to step into Einstein's general theory of 183 00:08:45.559 --> 00:08:46.320 relativity for this. 184 00:08:46.399 --> 00:08:47.159 Okay, let's do it. 185 00:08:47.399 --> 00:08:52.200 So. Einstein revolutionized our understanding of gravity by showing that 186 00:08:52.240 --> 00:08:55.279 it isn't just you know, a magnetic like pull between 187 00:08:55.320 --> 00:08:59.440 objects mass actually bends the fabric of space and time itself. 188 00:08:59.559 --> 00:09:02.519 Right. Classic analogy is the bowling ball on a trampoline. 189 00:09:02.600 --> 00:09:05.559 Yeah, the heavy ball creates a deep dip in the fabric, 190 00:09:05.600 --> 00:09:08.600 and if you roll a marble nearby, its path curves 191 00:09:08.639 --> 00:09:09.480 down into the dip. 192 00:09:09.639 --> 00:09:12.799 The trampoline analogy is great for picturing the dip. But 193 00:09:13.559 --> 00:09:16.200 and correct me if I'm wrong. Light doesn't roll. Light 194 00:09:16.279 --> 00:09:19.039 always travels in a perfectly straight line. That's a fundamental 195 00:09:19.120 --> 00:09:19.960 rule of the universe. 196 00:09:20.000 --> 00:09:22.519 Well, light does travel in a straight line, But what 197 00:09:22.679 --> 00:09:26.799 happens when the space it's traveling through is curved. Imagine 198 00:09:26.840 --> 00:09:29.120 drawing a straight line on a flat piece of paper. 199 00:09:29.639 --> 00:09:32.759 Now crumple that paper or wrap it around a sphere. 200 00:09:32.840 --> 00:09:35.120 The line you drew is still straight relative to the 201 00:09:35.159 --> 00:09:36.320 surface of the paper. 202 00:09:36.240 --> 00:09:39.519 Exactly, but in three dimensional space it's bending and curving 203 00:09:39.559 --> 00:09:40.440 along with the paper. 204 00:09:40.559 --> 00:09:42.639 Okay, that makes sense. So the light from our little 205 00:09:42.639 --> 00:09:45.840 red dot QSO one is speeding toward Earth, but sitting 206 00:09:45.840 --> 00:09:48.360 directly between us and QSO one is Pandora's cluster. 207 00:09:48.679 --> 00:09:52.600 And Pidora's cluster contains the mass of trillions of stars, 208 00:09:53.080 --> 00:09:56.519 massive amounts of gas, and just vast halos of dark matter. 209 00:09:57.840 --> 00:09:59.360 It is a gravitational heavyweight. 210 00:09:59.360 --> 00:10:01.440 So that's a huge bowling ball on the trampoline. 211 00:10:01.600 --> 00:10:05.120 Huge. It warps the space around it so severely that 212 00:10:05.159 --> 00:10:08.200 when the light from QSO one approaches, it's forced to 213 00:10:08.200 --> 00:10:12.559 travel through this warped curved space. The cluster essentially pinches 214 00:10:12.600 --> 00:10:16.039 the light paths together, focusing them toward us, just like. 215 00:10:16.000 --> 00:10:19.679 A literal magnifying glass focuses sunlight exactly like that, it 216 00:10:19.720 --> 00:10:23.240 concentrates the light, making QSO one appear much brighter and 217 00:10:23.320 --> 00:10:24.519 larger than it actually is. 218 00:10:24.759 --> 00:10:28.879 But gravitational lenses are not polished glass. They are lumpy, chaotic, 219 00:10:29.000 --> 00:10:32.159 and uneven. Because the mass in a galaxy cluster isn't 220 00:10:32.159 --> 00:10:35.759 distributed perfectly right, it's clumpy, very clumpy, and this leads 221 00:10:35.759 --> 00:10:38.720 to a fascinating side effect. The light from QSO one 222 00:10:38.799 --> 00:10:41.559 doesn't just take one curved path around the cluster. It 223 00:10:41.559 --> 00:10:44.720 takes multiple paths. Wait, really, yeah, some light goes left 224 00:10:44.720 --> 00:10:47.559 around a particularly dense pocket of dark matter, some light 225 00:10:47.600 --> 00:10:49.080 goes right, some goes over the top. 226 00:10:49.279 --> 00:10:51.679 And because space is warped differently on the left side 227 00:10:51.720 --> 00:10:54.120 than the right side, those paths are different lengths. 228 00:10:54.240 --> 00:10:57.080 Exactly. Yeah, the light taking the left path might arrive 229 00:10:57.159 --> 00:11:00.000 at Earth years before the light taking the right path. 230 00:11:00.200 --> 00:11:00.639 Wow. 231 00:11:00.960 --> 00:11:04.279 And from our perspective on Earth, looking back at the cluster, 232 00:11:04.679 --> 00:11:08.000 we don't just see one magnified, little red dot. We 233 00:11:08.039 --> 00:11:12.600 see three distinct, separate images of QSO one smeared across 234 00:11:12.639 --> 00:11:13.600 different parts of the sky. 235 00:11:13.759 --> 00:11:15.960 See. I have to play the skeptic again here, seeing 236 00:11:16.080 --> 00:11:21.039 three distorted smeared copies of a galaxy scattered around a cluster. 237 00:11:21.440 --> 00:11:24.000 That sounds like an absolute nightmare for a data scientist. 238 00:11:24.120 --> 00:11:25.720 Oh, it's incredibly complex. 239 00:11:25.879 --> 00:11:28.840 It's literally a funhouse mirror. If you look at yourself 240 00:11:28.879 --> 00:11:30.879 in a funhouse mirror, your head is huge, your legs 241 00:11:30.879 --> 00:11:34.200 are tiny, your waist is warped. You can't use that 242 00:11:34.240 --> 00:11:37.440 reflection to accurately measure your height or your weight. Right, So, 243 00:11:37.480 --> 00:11:40.639 if QUSO one is distorted by this cosmic funhouse mirror, 244 00:11:40.919 --> 00:11:43.559 how can we possibly trust any measurements we take of it. 245 00:11:43.759 --> 00:11:47.759 Well, that is the paradox of gravitational lensing. The spatial image, 246 00:11:47.919 --> 00:11:49.960 you know, the physical shape we see on the screen 247 00:11:50.200 --> 00:11:53.559 is absolutely distorted. If we tried to measure its exact 248 00:11:53.600 --> 00:11:57.600 physical boundaries based purely on the picture, we'd be completely wrong. 249 00:11:57.840 --> 00:12:01.720 But we aren't just taking photographs. You're taking spectra. And 250 00:12:01.759 --> 00:12:04.480 while the funhouse mirror changes the shape of the image, 251 00:12:04.960 --> 00:12:07.960 it does not change the fundamental properties of the light itself. 252 00:12:08.080 --> 00:12:09.639 Oh I see, Yeah. 253 00:12:09.919 --> 00:12:13.639 The wavelengths of light, the chemical fingerprints embedded in that light, 254 00:12:13.720 --> 00:12:17.200 the velocity signatures, those remain pristine. 255 00:12:17.480 --> 00:12:19.799 Okay, so the funhouse mirror might stretch my face, but 256 00:12:19.840 --> 00:12:21.159 it doesn't change the color of my. 257 00:12:21.120 --> 00:12:24.480 Eyes precisely, and more importantly, the magnification effect, the sheer 258 00:12:24.519 --> 00:12:28.159 brightening of the object, is what gives us enough raw photons, 259 00:12:28.279 --> 00:12:32.039 enough actual light particles to feed into our most advanced instruments. 260 00:12:32.360 --> 00:12:34.440 So we need the distortion we do. 261 00:12:35.039 --> 00:12:37.519 Without the funhouse mirror, the light from qso one would 262 00:12:37.559 --> 00:12:40.600 just be too faint to analyze. The distortion is the 263 00:12:40.639 --> 00:12:43.679 price of admission for the magnification. 264 00:12:43.200 --> 00:12:45.399 And the instrument that paid that price of admission The 265 00:12:45.399 --> 00:12:50.039 one that actually decoded this light is the Near Infrared spectrograph. 266 00:12:49.600 --> 00:12:51.679 On James Web Yes, the nir. 267 00:12:51.440 --> 00:12:57.159 SPEC, specifically using something called an integral field unit or IFU. 268 00:12:58.039 --> 00:13:00.399 I think it's worth taking a moment to explain how 269 00:13:00.399 --> 00:13:03.039 this piece of technology works, because it's really the key 270 00:13:03.080 --> 00:13:05.600 to this entire discovery. This isn't just a camera. 271 00:13:05.519 --> 00:13:07.720 No, not at all. A standard camera gives you a 272 00:13:07.720 --> 00:13:10.360 two dimensional picture. You see a glowing dot and you 273 00:13:10.360 --> 00:13:13.360 can measure how bright it is and maybe it's general color. 274 00:13:13.720 --> 00:13:16.440 A sectograph, on the other hand, takes the light from 275 00:13:16.440 --> 00:13:19.960 a single point and passes it through a prism or 276 00:13:20.000 --> 00:13:24.519 a diffraction grating, splitting it into a rainbow. 277 00:13:23.440 --> 00:13:26.000 Just like Pink Floyd's Dark Side of the Moon album. 278 00:13:25.720 --> 00:13:28.840 Cover, exactly like that. And when you look at that rainbow, 279 00:13:28.840 --> 00:13:32.279 you see dark bands or bright lines at very specific colors. 280 00:13:32.799 --> 00:13:34.879 Those lines are chemical fingerprints. 281 00:13:35.000 --> 00:13:35.600 Fingerprints. 282 00:13:35.679 --> 00:13:39.080 Yeah, every element in the universe, hydrogen, oxygen, carbon, absorbs 283 00:13:39.080 --> 00:13:43.279 and in its light at incredibly specific, unique wavelengths. By 284 00:13:43.279 --> 00:13:45.480 looking at the bar code of lines in the spectrum, 285 00:13:45.639 --> 00:13:48.000 we know exactly what an object is made of without 286 00:13:48.039 --> 00:13:49.000 ever having to go there. 287 00:13:49.480 --> 00:13:52.440 But the integral field unit, the IFU takes this a 288 00:13:52.480 --> 00:13:55.080 step further, doesn't. It doesn't just take one spectrum of 289 00:13:55.120 --> 00:13:56.000 the whole object. 290 00:13:56.320 --> 00:13:59.679 No, the IFU is an engineering morvel. It takes the 291 00:13:59.720 --> 00:14:03.000 image page of QSO one and slices it up into 292 00:14:03.039 --> 00:14:07.120 a grid of hundreds of tiny individual pixels, and then 293 00:14:07.559 --> 00:14:10.679 it takes complete separate spectrum for every single one of 294 00:14:10.679 --> 00:14:13.039 those pixels simultaneously. 295 00:14:12.279 --> 00:14:15.519 Wait simultaneously. So instead of just saying this whole dot 296 00:14:15.559 --> 00:14:18.360 is made of hydrogen, the if you can say the 297 00:14:18.360 --> 00:14:21.120 top left corner has this chemical makeup, the bottom right 298 00:14:21.159 --> 00:14:23.279 has this makeup, and the center has this make up. 299 00:14:23.279 --> 00:14:25.720 Precisely, it's a three D data cube. You get an 300 00:14:25.840 --> 00:14:28.200 X and y axis for the picture and the Z 301 00:14:28.399 --> 00:14:31.320 axis for the chemistry of every microscopic piece of the picture. 302 00:14:31.399 --> 00:14:34.919 That is unbelievable, And chemistry isn't all the spectrum tells us. 303 00:14:35.159 --> 00:14:39.799 The spectrum also reveals motion. And this is how the researchers, 304 00:14:40.279 --> 00:14:44.159 led by scientists like Igness George Papalis and cosen wal Marcantini, 305 00:14:44.360 --> 00:14:45.879 this is how they achieved the impossible. 306 00:14:46.080 --> 00:14:47.559 They directly wighed the black hole. 307 00:14:47.600 --> 00:14:48.000 They did. 308 00:14:48.360 --> 00:14:51.039 Okay, we mentioned earlier that we measure motion using the 309 00:14:51.080 --> 00:14:53.759 Doppler effect. Let's make sure the mechanics of that are 310 00:14:53.799 --> 00:14:55.440 crystal clear for everyone listening. 311 00:14:55.480 --> 00:14:58.799 Sure, most people experience the Doppler effect with sound. You 312 00:14:58.799 --> 00:15:01.120 know you hear an ambulance come down the street towards you. 313 00:15:01.279 --> 00:15:04.399 As it moves towards you, it's chasing its own sound waves, 314 00:15:04.639 --> 00:15:07.799 compressing them. Compress sound waves mean a higher pitch. 315 00:15:09.279 --> 00:15:10.759 But the moment it passes you. 316 00:15:10.919 --> 00:15:13.120 Exactly the moment it passes you and drives away, the 317 00:15:13.159 --> 00:15:17.480 sound waves are stretched out and the pitch drops instantly OO. 318 00:15:19.960 --> 00:15:22.600 And light does the exact same thing, because light is 319 00:15:22.639 --> 00:15:23.120 a wave. 320 00:15:23.360 --> 00:15:26.480 Yes, if a cloud of glowing hydrogen gas in QSO 321 00:15:26.519 --> 00:15:29.440 one is moving toward Earth, its light waves are compressed 322 00:15:29.919 --> 00:15:33.360 in the spectrum of light. Shorter compressed waves shift toward 323 00:15:33.440 --> 00:15:34.120 the blue end of the. 324 00:15:34.120 --> 00:15:36.120 Rainbow, which we call blue shift right. 325 00:15:36.159 --> 00:15:38.000 And if the gas is moving away from us, the 326 00:15:38.039 --> 00:15:40.360 waves stretch out and shift toward the red end of 327 00:15:40.360 --> 00:15:41.720 the spectrum red shift. 328 00:15:41.879 --> 00:15:44.960 So. Using the IFU, the researchers looked at the cloud 329 00:15:45.000 --> 00:15:47.919 of hydrogen gas swirling around the center of QSO one. 330 00:15:48.120 --> 00:15:50.600 Because it's swirling, one side of the gas cloud is 331 00:15:50.679 --> 00:15:52.960 naturally coming toward us as it rotates and the other 332 00:15:53.039 --> 00:15:55.960 side is moving away exactly the if you allowed them 333 00:15:55.960 --> 00:15:58.159 to look at the left pixel and see a blue shift, 334 00:15:58.279 --> 00:16:01.519 and look at the right pixel and see a yes. 335 00:16:01.879 --> 00:16:05.000 And by measuring exactly how blue or how red the 336 00:16:05.080 --> 00:16:08.840 light was, they could calculate the exact velocity of the gas. 337 00:16:09.000 --> 00:16:11.960 They mapped the speed of a gas cloud thirteen billion 338 00:16:12.039 --> 00:16:13.240 light years away, And the. 339 00:16:13.200 --> 00:16:15.960 Map they generated is the smoking gun that destroyed the 340 00:16:15.960 --> 00:16:19.440 classical model. Why because when they plotted the velocity of 341 00:16:19.440 --> 00:16:21.960 the gas against its distance from the exact center of 342 00:16:21.960 --> 00:16:25.279 the object, they didn't just see a random, swirling mess. 343 00:16:25.559 --> 00:16:31.639 They saw a highly structured, mathematically perfect curve known as Kepplearian. 344 00:16:31.000 --> 00:16:35.120 Motion Giplarian motion, named after Johannes Kepler, the astronomer who 345 00:16:35.200 --> 00:16:37.279 figured out the laws of planetary motion in our own 346 00:16:37.320 --> 00:16:40.960 solar system in the seventeenth century. Let's visualize this, because 347 00:16:41.000 --> 00:16:43.519 it is the absolute crux of the argument. Think of 348 00:16:43.559 --> 00:16:47.440 how our solar system operates. Mercury is the closest planet 349 00:16:47.480 --> 00:16:49.879 to the Sun. It whips around the Sun at blazing 350 00:16:49.919 --> 00:16:53.120 speeds gray fast. Venus is further out, and it moves slower. 351 00:16:53.679 --> 00:16:56.480 Earth is further still, moving slower than Venus by the 352 00:16:56.519 --> 00:16:58.919 time you get out to Neptune, it is practically crawling 353 00:16:58.960 --> 00:17:02.120 along its orbit. Compared to Mercury. The speed drops off 354 00:17:02.159 --> 00:17:05.000 in a very specific steep curve the further way you get. 355 00:17:05.200 --> 00:17:08.000 And why does it drop off like that, Because gravity 356 00:17:08.079 --> 00:17:11.680 follows an inverse square law. The gravitational pull of the 357 00:17:11.720 --> 00:17:15.559 Sun weakens drastically as you move outward. But the only 358 00:17:15.599 --> 00:17:18.680 reason we see this clean, predictable curve in the Solar 359 00:17:18.680 --> 00:17:20.720 system is because the mass of the Solar system is 360 00:17:20.759 --> 00:17:24.400 not spread out over ninety nine point eight percent of 361 00:17:24.480 --> 00:17:27.759 all the mass in our entire solar system is concentrated 362 00:17:28.119 --> 00:17:32.880 in a single, incredibly dense central point, the Sun. The Sun. 363 00:17:33.119 --> 00:17:35.119 I like to picture it like a tether ball pole 364 00:17:35.160 --> 00:17:37.680 on a playground. You have a heavy, solid metal pole 365 00:17:37.720 --> 00:17:39.920 in the center and a ball attached to a string. 366 00:17:40.400 --> 00:17:42.400 When you hit the ball, it swings around the pole 367 00:17:42.440 --> 00:17:45.720 in a tight predictable arc. The tension is clear, the 368 00:17:45.759 --> 00:17:46.599 anchor is clear. 369 00:17:46.759 --> 00:17:47.680 That's a great analogy. 370 00:17:47.720 --> 00:17:49.759 The mass is in the middle and the gas or 371 00:17:49.799 --> 00:17:52.279 the ball simply responds to that central mass. 372 00:17:52.319 --> 00:17:54.559 And that is exactly what the IFU data showed in 373 00:17:54.599 --> 00:17:57.960 QSO one. The hydrogen gas closest to the center was 374 00:17:58.000 --> 00:18:00.960 moving at blistering speeds thousands of colometers per second. 375 00:18:01.039 --> 00:18:01.480 Wow. 376 00:18:01.599 --> 00:18:04.359 And as they measure the gas further out, the velocity 377 00:18:04.440 --> 00:18:08.640 dropped on a perfect Cuplearrian curve. The tether ball pole 378 00:18:08.759 --> 00:18:09.119 was there. 379 00:18:09.440 --> 00:18:11.680 But what if it wasn't a black hole? I mean, 380 00:18:11.799 --> 00:18:14.519 what if QSO one was just a really dense cluster 381 00:18:14.640 --> 00:18:17.359 of stars, like a normal galaxy in the making. 382 00:18:17.759 --> 00:18:21.480 Well, if QSO one was a normal, mature galaxy packed 383 00:18:21.480 --> 00:18:24.200 with stars, the mass would be distributed, it wouldn't be 384 00:18:24.240 --> 00:18:27.440 a tetherball pole. Okay, Imagine instead that the mass was 385 00:18:27.480 --> 00:18:31.400 a massive, chaotic swarm of bees. If you throw a 386 00:18:31.440 --> 00:18:34.279 ball through the swarm of bees, there was no single 387 00:18:34.400 --> 00:18:37.359 central anchor pulling on it. It gets pulled a little 388 00:18:37.400 --> 00:18:39.400 to the left by this clump of bees, a little 389 00:18:39.400 --> 00:18:40.599 to the right by that clump. 390 00:18:40.680 --> 00:18:43.240 So the rotation wouldn't be smooth like if you look 391 00:18:43.240 --> 00:18:45.920 at the rotation curve of a normal galaxy like the 392 00:18:45.920 --> 00:18:49.559 Milky Way, it does not drop off steeply at the edges. Right, 393 00:18:49.640 --> 00:18:51.680 the stars at the outer edge of our galaxy are 394 00:18:51.720 --> 00:18:55.319 moving surprisingly fast. That flat rotation curve is actually how 395 00:18:55.319 --> 00:18:58.240 we discovered dark matter, right, because there was invisible mass 396 00:18:58.240 --> 00:19:01.039 spread through the galaxy, pulling on the outer stars exactly. 397 00:19:01.319 --> 00:19:04.599 A distributed mass creates a flat or chaotic rotation curve. 398 00:19:05.039 --> 00:19:08.319 A concentrated mass creates a Coplearian curve. And the data 399 00:19:08.359 --> 00:19:11.599 from QSO one was undeniably keplarium. 400 00:19:11.119 --> 00:19:12.200 So it's concentrated. 401 00:19:12.559 --> 00:19:16.640