WEBVTT 00:00:00.000 --> 00:00:04.660 On February 14th, 1863, an astronomer basically 00:00:04.660 --> 00:00:06.719 squinted through this brass and glass telescope 00:00:06.719 --> 00:00:10.660 into a freezing winter sky and he found this 00:00:10.660 --> 00:00:13.039 peaceful glowing smudge in the constellation 00:00:13.039 --> 00:00:16.230 Perseus. Right, a very romantic Valentine's Day 00:00:16.230 --> 00:00:18.550 discovery. But he had, like, absolutely no idea 00:00:18.550 --> 00:00:21.550 he was actually documenting a 147 million year 00:00:21.550 --> 00:00:24.390 old crime scene. A violently active crime scene. 00:00:24.710 --> 00:00:27.210 I mean, we are looking at an object that is fundamentally 00:00:27.210 --> 00:00:29.489 tearing itself and its closest neighbor apart. 00:00:29.710 --> 00:00:32.549 Wow. Well, welcome to the Deep Dive. Today we're 00:00:32.549 --> 00:00:37.329 taking a look at a really dense, data -rich Wikipedia 00:00:37.329 --> 00:00:40.030 entry about a specific spiral galaxy known as 00:00:40.030 --> 00:00:45.280 NGC 1268. Right. And we're going to extract the 00:00:45.280 --> 00:00:47.560 hidden physics and just the sheer drama inside 00:00:47.560 --> 00:00:49.939 those numbers. Because our mission today is to 00:00:49.939 --> 00:00:52.259 decode this complex astronomical data for you. 00:00:52.399 --> 00:00:55.259 Yeah, exactly. Bypassing the dry tables to really 00:00:55.259 --> 00:00:57.439 understand what a single galaxy's profile tells 00:00:57.439 --> 00:01:00.060 us about the dynamic fluid nature of our cosmic 00:01:00.060 --> 00:01:02.079 neighborhood. Right. Because it's so easy to 00:01:02.079 --> 00:01:04.239 just look at a source text filled with coordinates, 00:01:04.519 --> 00:01:06.519 classification codes, decimal points. Just let 00:01:06.519 --> 00:01:09.319 your eyes glaze over. Oh, absolutely. But our 00:01:09.319 --> 00:01:12.079 goal here is to translate that rigid data into 00:01:12.079 --> 00:01:14.900 a three -dimensional living picture of the universe. 00:01:15.420 --> 00:01:18.439 Because every single metric on this page is a 00:01:18.439 --> 00:01:20.680 clue to how this galaxy functions. You know, 00:01:20.799 --> 00:01:24.019 how it was born and how it might eventually die. 00:01:24.170 --> 00:01:26.650 OK, let's unpack this. To understand the crime 00:01:26.650 --> 00:01:28.590 scene, we really need to look at the victim's 00:01:28.590 --> 00:01:31.810 profile first. OK, sure. So the source classifies 00:01:31.810 --> 00:01:35.849 NGC 1268 as an intermediate spiral galaxy, right, 00:01:36.230 --> 00:01:38.409 located in the constellation Perseus. Right, 00:01:38.510 --> 00:01:40.170 the Perseus constellation. But then it gives 00:01:40.170 --> 00:01:42.909 this highly specific morphological classification 00:01:42.909 --> 00:01:46.030 that says it's an SAB parentheses, RS parentheses, 00:01:46.689 --> 00:01:50.469 lowercase BB, which, I mean, I know the S stands 00:01:50.469 --> 00:01:52.569 for spiral, but that string of letters just feels 00:01:52.569 --> 00:01:54.609 like a writer password. It really does. What 00:01:54.609 --> 00:01:57.969 structural anatomy does SEB ORS -B actually describe? 00:01:58.269 --> 00:02:00.409 Well, it's actually an incredibly precise map 00:02:00.409 --> 00:02:02.750 of the galaxy's skeleton. Oh, really? Yeah, so 00:02:02.750 --> 00:02:04.829 the SEB part means it's an intermediate spiral. 00:02:05.189 --> 00:02:07.189 It has a central bar of stars cutting across 00:02:07.189 --> 00:02:11.129 its core. But that bar isn't quite as pronounced 00:02:11.129 --> 00:02:14.090 or rigidly defined as the one in, say, our own 00:02:14.090 --> 00:02:16.759 Milky Way. OK, got it. Then you have the Rs in 00:02:16.759 --> 00:02:19.919 parentheses. That indicates an inner ring structure. 00:02:20.419 --> 00:02:24.039 So gas and stars are congregating in this loose 00:02:24.039 --> 00:02:27.560 ring just outside that central bar. Oh, fascinating. 00:02:27.879 --> 00:02:30.219 And finally, that lowercase b tells us about 00:02:30.219 --> 00:02:32.979 the spiral arms themselves. They aren't tightly 00:02:32.979 --> 00:02:34.780 wound around the core like a school of thread, 00:02:34.800 --> 00:02:37.120 but they're not completely loose and fragmented 00:02:37.120 --> 00:02:39.199 either. They're, you know, moderately wound. 00:02:39.780 --> 00:02:42.860 OK, so we're picturing a central glowing core, 00:02:43.919 --> 00:02:47.479 a faint straight bar of stars across the middle, 00:02:47.800 --> 00:02:50.360 a glowing ring around that, and then sweeping 00:02:50.360 --> 00:02:52.960 arms kind of trailing off into the dark. Precisely. 00:02:52.979 --> 00:02:55.280 And it's doing all of this on a massive scale. 00:02:55.379 --> 00:02:57.759 I mean, the data puts its size at roughly 55 00:02:57.759 --> 00:03:00.580 ,400 light years across. Which is smaller than 00:03:00.580 --> 00:03:02.400 our Milky Way, but we're still talking about 00:03:02.400 --> 00:03:04.500 a structure containing billions of stars. Oh, 00:03:04.580 --> 00:03:06.639 easily. And yet the source notes its apparent 00:03:06.639 --> 00:03:10.949 size from Earth is tiny. Like, just... 1 .0 by 00:03:10.949 --> 00:03:13.030 0 .6 arc minutes. So if you're looking up at 00:03:13.030 --> 00:03:14.750 the night sky, you are absolutely not seeing 00:03:14.750 --> 00:03:16.430 this with the naked eye. Not a chance. I mean, 00:03:16.590 --> 00:03:19.199 an arc minute is a 60th of a degree. To put that 00:03:19.199 --> 00:03:21.780 in perspective, the full moon is about 30 arc 00:03:21.780 --> 00:03:26.120 minutes across. So NGC 1268 is a fraction of 00:03:26.120 --> 00:03:28.060 a fraction of the size of the moon in our sky. 00:03:28.280 --> 00:03:30.699 It's incredibly faint and incredibly small from 00:03:30.699 --> 00:03:33.020 our vantage point, which makes sense given the 00:03:33.020 --> 00:03:37.099 distance listed here. It's 147 .3 million light 00:03:37.099 --> 00:03:39.300 years from Earth. Yeah. And I noticed the data 00:03:39.300 --> 00:03:41.979 includes an air margin there, plus or minus 10 00:03:41.979 --> 00:03:44.699 .3 million light years. Yeah, which really highlights 00:03:44.699 --> 00:03:47.500 the extreme difficulty of measuring cosmic distances. 00:03:48.100 --> 00:03:51.280 When an object is that far away, our standard 00:03:51.280 --> 00:03:54.099 geometric tools like measuring parallax as the 00:03:54.099 --> 00:03:56.340 Earth moves around the Sun, they completely break 00:03:56.340 --> 00:03:57.860 down. They just don't work anymore. Exactly. 00:03:57.919 --> 00:04:00.539 We have to rely on the behavior of light itself 00:04:00.539 --> 00:04:03.180 to gauge the distance, which is what introduces 00:04:03.180 --> 00:04:05.360 that margin of error. Right. Now looking at the 00:04:05.360 --> 00:04:08.759 data, it pins its right ascension down to, let's 00:04:08.759 --> 00:04:12.080 see, three hours, 18 minutes, 45 point... 1985 00:04:12.080 --> 00:04:14.599 seconds very specific yeah and the declination 00:04:14.599 --> 00:04:17.740 is plus 41 degrees 29 minutes 19 point something 00:04:17.740 --> 00:04:20.800 seconds we don't need to read out the raw gps 00:04:20.800 --> 00:04:22.220 coordinates to understand why that precision 00:04:22.220 --> 00:04:24.759 matters though you need those exact coordinates 00:04:24.759 --> 00:04:26.959 because of how many different teams are constantly 00:04:26.959 --> 00:04:29.779 looking at this exact spot exactly and that actually 00:04:29.779 --> 00:04:31.300 brings up something that stood out to me in the 00:04:31.300 --> 00:04:35.279 source the sheer number of catalog names Yes, 00:04:35.860 --> 00:04:38.360 the alphabet soup of astronomical designations. 00:04:38.459 --> 00:04:42.079 Right. I mean, it's primarily known as NGC 1268 00:04:42.079 --> 00:04:45.420 for the New General Catalog. But the data lists 00:04:45.420 --> 00:04:47.519 all these other alternate identities. There's 00:04:47.519 --> 00:04:56.079 UGC 2658, MCG plus 0707056, PGC 12332. CGCG 5493. 00:04:56.220 --> 00:04:58.579 Yes. All of those. And my initial thought was 00:04:58.579 --> 00:05:00.040 that this is like a person having, you know, 00:05:00.199 --> 00:05:02.240 a driver's license for the DMV, a passport for 00:05:02.240 --> 00:05:04.480 travel, and a social security number for the 00:05:04.480 --> 00:05:07.160 IRS. But it's more than just administrative paperwork, 00:05:07.259 --> 00:05:09.060 isn't it? It is, yeah. Because these different 00:05:09.060 --> 00:05:10.639 acronyms represent fundamentally different ways 00:05:10.639 --> 00:05:12.699 of seeing the galaxy, right? They absolutely 00:05:12.699 --> 00:05:15.579 do. That's a vital distinction. When you see 00:05:15.579 --> 00:05:18.000 a list of catalog names like that, you aren't 00:05:18.000 --> 00:05:20.079 just seeing different filing cabinets. You're 00:05:20.079 --> 00:05:22.459 really seeing the history of human observation. 00:05:22.560 --> 00:05:25.079 Oh, that makes sense. For instance, UGC is the 00:05:25.079 --> 00:05:28.360 Uppsala General Catalog, which focused on galaxies 00:05:28.360 --> 00:05:30.579 visible from the northern hemisphere above a 00:05:30.579 --> 00:05:35.100 certain size limit. But... MCG is the Morphological 00:05:35.100 --> 00:05:38.720 Catalog of Galaxies, which was this massive Soviet 00:05:38.720 --> 00:05:41.600 project that meticulously classified the visual 00:05:41.600 --> 00:05:44.660 shapes of tens of thousands of galaxies based 00:05:44.660 --> 00:05:46.959 on photographic plates. OK, so it's more like 00:05:46.959 --> 00:05:49.800 a medical file. The NGC name might be the basic 00:05:49.800 --> 00:05:52.139 photograph of the patient, but another catalog 00:05:52.139 --> 00:05:54.939 might be the X -ray showing the hot gas. And 00:05:54.939 --> 00:05:57.480 another might be the MRI showing the ancient, 00:05:57.560 --> 00:05:59.939 cooler stars in the infrared spectrum. That is 00:05:59.939 --> 00:06:02.000 a much better way to think about it, yeah. Different 00:06:02.000 --> 00:06:03.899 sky surveys are conducted by different teams 00:06:03.899 --> 00:06:05.899 using varying wavelengths of light to achieve 00:06:05.899 --> 00:06:08.379 completely different scientific goals. If a team 00:06:08.379 --> 00:06:10.920 maps the sky looking specifically for radio emissions 00:06:10.920 --> 00:06:13.500 from active galactic nuclei, they generate a 00:06:13.500 --> 00:06:16.439 new catalog. If your galaxy emits those radio 00:06:16.439 --> 00:06:19.379 waves, it gets a new ID tag. So having five or 00:06:19.379 --> 00:06:21.980 six different catalog designations tells you 00:06:21.980 --> 00:06:26.699 that NGC 1268 is an object of sustained multidisciplinary 00:06:26.699 --> 00:06:28.839 scientific interest. Right. But all those different 00:06:28.839 --> 00:06:31.879 catalogs are basically taking snapshots of a 00:06:31.879 --> 00:06:34.199 moving target. And when I say moving, the data 00:06:34.199 --> 00:06:36.779 here is just staggering. It really is. The source 00:06:36.779 --> 00:06:41.639 lists its heliocentric radial velocity at 3 ,222 00:06:41.639 --> 00:06:43.939 kilometers per second with an incredibly tight 00:06:43.939 --> 00:06:46.439 error margin of just plus or minus 2 kilometers 00:06:46.439 --> 00:06:49.060 per second. And it also lists its redshift at 00:06:49.060 --> 00:06:53.709 0 .010748. Right. And those two numbers are inextricably 00:06:53.709 --> 00:06:55.449 linked. Well, I know that redshift indicates 00:06:55.449 --> 00:06:57.350 an object is moving away from us, right? The 00:06:57.350 --> 00:06:58.930 light waves are literally being stretched out 00:06:58.930 --> 00:07:00.430 toward the red end of the spectrum because the 00:07:00.430 --> 00:07:03.370 universe is expanding. Exactly. But 3 ,222 kilometers 00:07:03.370 --> 00:07:06.029 a second, is that speed entirely due to the background 00:07:06.029 --> 00:07:07.990 expansion of the universe? Yeah. Like the Hubble 00:07:07.990 --> 00:07:10.589 flow? Right. Or does a specific redshift of 0 00:07:10.589 --> 00:07:13.670 .010748 suggest something else is pulling on 00:07:13.670 --> 00:07:16.149 it? That is exactly the right question to ask. 00:07:16.399 --> 00:07:20.120 At a distance of 147 million light years, the 00:07:20.120 --> 00:07:22.079 expansion of the universe certainly accounts 00:07:22.079 --> 00:07:24.660 for a large portion of that extreme velocity. 00:07:25.339 --> 00:07:27.860 As space itself stretches, the galaxy is carried 00:07:27.860 --> 00:07:30.379 away from us. But the precision of that measurement, 00:07:30.579 --> 00:07:32.540 plus or minus just two kilometers per second, 00:07:32.819 --> 00:07:36.160 allows astronomers to isolate its peculiar velocity. 00:07:36.240 --> 00:07:38.720 Peculiar velocity. Yeah, that is the galaxy's 00:07:38.720 --> 00:07:41.180 actual physical motion through its local environment, 00:07:41.720 --> 00:07:44.930 independent of cosmic expansion. Oh, wow. Which 00:07:44.930 --> 00:07:47.970 means it's falling towards something. It is barreling 00:07:47.970 --> 00:07:51.250 through space. And moving at 3 ,200 kilometers 00:07:51.250 --> 00:07:54.329 a second has severe consequences. You cannot 00:07:54.329 --> 00:07:56.389 tear through a neighborhood at that speed without 00:07:56.389 --> 00:07:58.529 interacting with your environment. Yeah, I'd 00:07:58.529 --> 00:08:00.509 imagine not. And that leads us to the critical 00:08:00.509 --> 00:08:04.269 context provided by the source. NGC 1268 is a 00:08:04.269 --> 00:08:06.949 member of the Perseus Cluster. Now anyone following 00:08:06.949 --> 00:08:10.550 astronomy knows that a galaxy cluster is a massive 00:08:10.550 --> 00:08:13.439 gravitationally bound system. But the Perseus 00:08:13.439 --> 00:08:15.540 Cluster is particularly notorious, isn't it? 00:08:15.680 --> 00:08:18.199 Oh, very much so. Like, it is one of the most 00:08:18.199 --> 00:08:21.139 massive objects in the known universe, filled 00:08:21.139 --> 00:08:24.060 with thousands of galaxies surrounded by a vast 00:08:24.060 --> 00:08:27.139 cloud of multi -million -degree X -ray gas. It 00:08:27.139 --> 00:08:30.519 is an incredibly dense, chaotic, and high -friction 00:08:30.519 --> 00:08:32.909 environment. Being a member of the Perseus cluster 00:08:32.909 --> 00:08:37.210 means NGC 1268 is constantly navigating a treacherous 00:08:37.210 --> 00:08:39.309 gravitational landscape. Just dodging traffic 00:08:39.309 --> 00:08:41.649 constantly. Pretty much, and the source specifically 00:08:41.649 --> 00:08:43.909 notes the visible damage of that navigation. 00:08:44.450 --> 00:08:47.610 It states that NGC 1268 appears to show signs 00:08:47.610 --> 00:08:50.149 of distortion in the form of bridges, and that 00:08:50.149 --> 00:08:52.269 these features are likely the result of a strong 00:08:52.269 --> 00:08:56.070 interaction with a neighboring galaxy, NGC 1267. 00:08:56.309 --> 00:08:58.870 Okay, so when the source says bridges, it's easy 00:08:58.870 --> 00:09:02.820 to picture a rigid structure, a literal suspension 00:09:02.820 --> 00:09:06.000 bridge connecting two cosmic islands. Gravity 00:09:06.000 --> 00:09:08.019 doesn't build suspension bridges out of stars. 00:09:08.139 --> 00:09:10.159 No, it doesn't. How does a stream of stellar 00:09:10.159 --> 00:09:12.539 material physically hold together across the 00:09:12.539 --> 00:09:14.759 vacuum of space? Yeah. Like, is this more like 00:09:14.759 --> 00:09:17.240 pulling apart warm taffy? Are these two galaxies 00:09:17.240 --> 00:09:19.279 actually ripping stars from each other's outer 00:09:19.279 --> 00:09:21.620 edges? What's fascinating here is that the taffy 00:09:21.620 --> 00:09:24.139 analogy is spot -on. They are absolutely doing 00:09:24.139 --> 00:09:27.139 that, and it all comes down to differential gravitational 00:09:27.139 --> 00:09:30.240 pull, or tidal forces. Like the moon pulling 00:09:30.240 --> 00:09:32.500 on Earth's oceans to create high and low tides. 00:09:32.659 --> 00:09:35.399 Exactly like that, but scaled up to billions 00:09:35.399 --> 00:09:40.500 of solar masses. As NGC 1268 and NGC 1267 pass 00:09:40.500 --> 00:09:42.960 close to each other, the gravitational field 00:09:42.960 --> 00:09:47.240 of 1267 pulls on the near side of 1268 much more 00:09:47.240 --> 00:09:49.320 strongly than it pulls on the far side. Because 00:09:49.320 --> 00:09:52.500 gravity weakens with distance. So the side facing 00:09:52.500 --> 00:09:55.019 the neighbor feels a much more violent tug. Correct. 00:09:55.320 --> 00:09:57.659 And that differential pull overcomes the internal 00:09:57.659 --> 00:10:00.700 gravity holding the galaxy's spiral arms together. 00:10:01.039 --> 00:10:04.059 Stars, gas, and dust are literally sheared off 00:10:04.059 --> 00:10:07.340 the outer edges. They get drawn out into a long 00:10:07.340 --> 00:10:10.139 trailing filament, a tidal tail or a bridge. 00:10:10.360 --> 00:10:11.980 But wait, if the gravity is pulling that hard, 00:10:12.120 --> 00:10:14.120 why don't the two galaxies just immediately collapse 00:10:14.120 --> 00:10:16.120 into each other? Like, why does it form a bridge 00:10:16.120 --> 00:10:18.899 instead of just a single instant car crash? Because 00:10:18.899 --> 00:10:20.600 of angular momentum, they aren't just falling 00:10:20.600 --> 00:10:21.840 straight toward each other. They're orbiting 00:10:21.840 --> 00:10:24.120 the center of the Perseus cluster, moving at 00:10:24.120 --> 00:10:26.179 incredible velocities. Oh, I see. So they're 00:10:26.179 --> 00:10:29.460 sliding past one another. The bridge is a visual 00:10:29.460 --> 00:10:32.759 record of their orbital dance. The material gets 00:10:32.759 --> 00:10:35.139 stretched out in the space between them as they 00:10:35.139 --> 00:10:38.389 swing by. It's essentially a slow motion fluid 00:10:38.389 --> 00:10:40.629 dynamics experiment playing out over millions 00:10:40.629 --> 00:10:43.309 of years. Exactly. The distortion, the pulling, 00:10:43.529 --> 00:10:46.450 the stretching it fundamentally alters the morphological 00:10:46.450 --> 00:10:48.129 classification we talked about earlier. Right. 00:10:48.289 --> 00:10:51.950 That SEPR's B shape is being warped in real time. 00:10:52.129 --> 00:10:54.629 And this is why it is so important to look past 00:10:54.629 --> 00:10:57.090 just the static numbers on a Wikipedia page. 00:10:57.809 --> 00:11:00.529 Galaxies are not static paintings. They are fluid. 00:11:00.799 --> 00:11:03.980 They're malleable. This interaction forces massive 00:11:03.980 --> 00:11:07.309 clouds of cold gas to collide. compressing them 00:11:07.309 --> 00:11:10.350 and triggering intense waves of new star formation. 00:11:10.850 --> 00:11:12.870 A violent interaction like this both destroys 00:11:12.870 --> 00:11:15.009 the existing structure of the galaxy and seeds 00:11:15.009 --> 00:11:17.190 the birth of millions of new stars. So it's a 00:11:17.190 --> 00:11:19.049 slow motion collision course where the debris 00:11:19.049 --> 00:11:21.110 is made of a glowing plasma. Beautifully tight, 00:11:21.129 --> 00:11:23.470 yeah. But that slow motion environment, the millions 00:11:23.470 --> 00:11:26.169 of years it takes to form a tidal bridge, that 00:11:26.169 --> 00:11:28.330 sets the stage for an event in the source data 00:11:28.330 --> 00:11:31.289 that is incredibly fast, like sudden, violent, 00:11:31.429 --> 00:11:34.769 and rapid. The Flash of 2008. Right. The data 00:11:34.769 --> 00:11:37.629 notes that a supernova was observed inside NGC 00:11:37.629 --> 00:11:41.629 1268. It was named SN 2008 and it was discovered 00:11:41.629 --> 00:11:45.029 on August 30th, 2008 by the Lick Observatory 00:11:45.029 --> 00:11:49.070 Supernova Search or LSSS. This completely shifts 00:11:49.070 --> 00:11:51.169 our timeline from millions of years to a matter 00:11:51.169 --> 00:11:53.429 of days. Yeah. And the numbers provided here 00:11:53.429 --> 00:11:55.370 require a bit of unpacking, I think. Oh, for 00:11:55.370 --> 00:11:56.889 sure. Here's where it gets really interesting. 00:11:57.389 --> 00:12:00.110 The source lists the overall apparent magnitude 00:12:00.110 --> 00:12:04.830 of the host galaxy. NGC 1268 as 14 .2, but it 00:12:04.830 --> 00:12:07.110 lists the magnitude of the supernova itself as 00:12:07.110 --> 00:12:10.409 18 .8. Right. Now in normal terms, higher numbers 00:12:10.409 --> 00:12:12.879 sound bigger and brighter. Wait, so the galaxy 00:12:12.879 --> 00:12:15.320 has a magnitude of 14 .2, but the supernova was 00:12:15.320 --> 00:12:19.080 18 .8. Is an 18 .8 magnitude explosion just blindingly 00:12:19.080 --> 00:12:21.159 bright? It's actually the exact opposite. I know 00:12:21.159 --> 00:12:23.299 it's counterintuitive, but the astronomical magnitude 00:12:23.299 --> 00:12:25.620 scales backward. Oh, really? Yeah, it originated 00:12:25.620 --> 00:12:27.820 from ancient astronomers who ranked stars from 00:12:27.820 --> 00:12:30.740 first class down to sixth class. So a smaller 00:12:30.740 --> 00:12:32.860 number is brighter and a larger number is dimmer. 00:12:33.299 --> 00:12:36.659 So an 18 .8 is incredibly dim. Substantially 00:12:36.659 --> 00:12:39.379 dim. To give you a sense of scale, the faintest 00:12:39.379 --> 00:12:41.799 objects you can see with the naked eye in a pitch 00:12:41.799 --> 00:12:45.440 black sky are around magnitude 6. The galaxy 00:12:45.440 --> 00:12:48.399 itself, at 14 .2, requires a serious telescope 00:12:48.399 --> 00:12:52.070 to capture. And the supernova is an 18 .8. Because 00:12:52.070 --> 00:12:54.629 the magnitude scale is logarithmic, that means 00:12:54.629 --> 00:12:57.450 the supernova was roughly 70 times fainter than 00:12:57.450 --> 00:12:59.529 the combined light of the galaxy it sits inside. 00:12:59.809 --> 00:13:02.350 Wow. Okay, so my question is, how on earth do 00:13:02.350 --> 00:13:05.429 you spot an 18 .8 magnitude pinprick of light 00:13:05.429 --> 00:13:08.570 against the glowing distorted backdrop of a 14 00:13:08.570 --> 00:13:11.889 .2 magnitude galaxy core? How does the LS team 00:13:11.889 --> 00:13:14.240 actually find that? They use a technique called 00:13:14.240 --> 00:13:16.740 digital image subtraction, and it relies entirely 00:13:16.740 --> 00:13:18.899 on automated telescopes and algorithms. Oh, so 00:13:18.899 --> 00:13:20.759 computers are doing the heavy lifting. Exactly. 00:13:20.960 --> 00:13:23.379 The Lick Observatory Supernova Search utilizes 00:13:23.379 --> 00:13:25.460 a robotic telescope that photographs thousands 00:13:25.460 --> 00:13:27.559 of galaxies every single night. The computer 00:13:27.559 --> 00:13:30.840 takes a new image of NGC 1268, lines it up pixel 00:13:30.840 --> 00:13:33.039 by pixel with an older reference image of the 00:13:33.039 --> 00:13:35.399 exact same galaxy, and literally subtracts the 00:13:35.399 --> 00:13:37.419 light of the old image from the new one. So if 00:13:37.419 --> 00:13:39.980 nothing is changed, the result is just a completely 00:13:39.980 --> 00:13:43.399 blank, black image. Yes. The blinding light of 00:13:43.399 --> 00:13:46.240 the galaxy's core is mathematically erased. But 00:13:46.240 --> 00:13:48.879 if a single star has exploded and brightened 00:13:48.879 --> 00:13:51.879 in the intervening days, that one pixel won't 00:13:51.879 --> 00:13:54.179 cancel out. It'll just pop up. Right. It'll leave 00:13:54.179 --> 00:13:57.419 a tiny faint dot on the subtracted image. That 00:13:57.419 --> 00:14:01.840 is how you catch an 18 .8 magnitude blink 147 00:14:01.840 --> 00:14:04.759 million light years away. That is an unbelievable 00:14:04.759 --> 00:14:07.259 feat of engineering. And it matters immensely 00:14:07.259 --> 00:14:11.100 because the source explicitly classifies SN2008B 00:14:11.100 --> 00:14:14.539 -ROM as a Typeo supernova. And in astronomy, 00:14:14.620 --> 00:14:17.279 finding a Typeoia is like striking gold, isn't 00:14:17.279 --> 00:14:20.110 it? Oh, it's the holy grail of cosmological distance 00:14:20.110 --> 00:14:22.190 measurement. Type Ia supernovae are what we call 00:14:22.190 --> 00:14:24.970 standard candles. Right. But how do we know they're 00:14:24.970 --> 00:14:26.429 standard? I mean, the universe is incredibly 00:14:26.429 --> 00:14:28.370 chaotic, as we've just established with the Perseus 00:14:28.370 --> 00:14:31.409 Cluster. How can we be sure that every type Ia 00:14:31.409 --> 00:14:33.809 supernovae explodes with the exact same underlying 00:14:33.809 --> 00:14:36.269 physics? Because of a very rigid physical threshold 00:14:36.269 --> 00:14:38.870 known as the Chandrasekhar Limit. The Chandrasekhar 00:14:38.870 --> 00:14:42.019 Limit? Yeah. A Type Ia doesn't happen to a massive 00:14:42.019 --> 00:14:44.440 star collapsing under its own weight. It happens 00:14:44.440 --> 00:14:47.580 in a binary system, where a dense, dead white 00:14:47.580 --> 00:14:50.679 dwarf star orbits a companion. The white dwarf 00:14:50.679 --> 00:14:53.539 acts like a parasite, using its intense gravity 00:14:53.539 --> 00:14:56.340 to slowly siphon gas off the companion star. 00:14:56.559 --> 00:15:00.059 Oh, so it's stealing mass. Exactly. And it keeps 00:15:00.059 --> 00:15:02.980 stealing mass until it hits a very specific mathematical 00:15:02.980 --> 00:15:06.259 tipping point, which is 1 .44 times the mass 00:15:06.259 --> 00:15:09.590 of our sun. OK, 1 .44. The instant it crosses 00:15:09.590 --> 00:15:11.950 that threshold, the white dwarf can no longer 00:15:11.950 --> 00:15:14.470 support its own weight. It collapses and detonates 00:15:14.470 --> 00:15:17.070 in a runaway thermonuclear explosion. Because 00:15:17.070 --> 00:15:20.549 that trigger point 1 .44 solar masses is a fundamental 00:15:20.549 --> 00:15:23.230 law of physics, the resulting explosion always 00:15:23.230 --> 00:15:26.110 produces roughly the same peak absolute luminosity. 00:15:26.350 --> 00:15:29.149 I see. It's like knowing exactly how loud a specific 00:15:29.149 --> 00:15:31.389 standardized model of a firecracker is. If you 00:15:31.389 --> 00:15:33.090 know its true volume and you hear it go off in 00:15:33.090 --> 00:15:35.090 the distance as barely a whisper, you can use 00:15:35.090 --> 00:15:37.029 the dampening of the sound to calculate exactly 00:15:37.029 --> 00:15:39.289 how many miles the way it detonated. That is 00:15:39.289 --> 00:15:42.070 a perfect analogy, yeah. By measuring the incredibly 00:15:42.070 --> 00:15:46.549 faint 18 .8 apparent magnitude of SN 2008 frown 00:15:46.549 --> 00:15:48.610 and comparing it to the known true brightness 00:15:48.610 --> 00:15:51.870 of a type E explosion, astronomers can independently 00:15:51.870 --> 00:15:56.330 calculate the distance to NGC 1268. It is a critical 00:15:56.330 --> 00:15:58.970 mathematical check that verifies that plus or 00:15:58.970 --> 00:16:01.970 minus 10 .3 million light -year distance we discussed 00:16:01.970 --> 00:16:04.769 at the start. Finding a standard candle inside 00:16:04.769 --> 00:16:07.149 this galaxy calibrates our entire understanding 00:16:06.919 --> 00:16:10.059 of its place in the Perseus cluster. That's incredible. 00:16:10.200 --> 00:16:12.059 And that standard candle really serves as a pivot 00:16:12.059 --> 00:16:14.940 point for the human timeline of discovery embedded 00:16:14.940 --> 00:16:17.320 in this data, right? We have this ultra -modern 00:16:17.320 --> 00:16:20.139 2008 discovery facilitated by robotic telescopes, 00:16:20.700 --> 00:16:23.340 algorithmic image subtraction, and advanced astrophysics 00:16:23.340 --> 00:16:25.480 regarding the Chandrasekhar limit. Right. Very 00:16:25.480 --> 00:16:27.740 cutting edge. But the source grounds this modern 00:16:27.740 --> 00:16:29.700 science by looking back to how our view of this 00:16:29.700 --> 00:16:32.759 galaxy began. Go back to Heinrich de Rest, February 00:16:32.759 --> 00:16:36.279 14th, 1863. Squinting through a 19th century... 00:16:36.139 --> 00:16:38.899 optical telescope in the freezing cold. Right. 00:16:39.159 --> 00:16:41.820 He had no computers. No image subtraction. He 00:16:41.820 --> 00:16:45.120 was just a human eye behind glass lenses sketching 00:16:45.120 --> 00:16:47.960 a smudge by hand. And contrast that with another 00:16:47.960 --> 00:16:50.799 detail in the source. It provides an image of 00:16:50.799 --> 00:16:55.200 NGC 1268 taken recently by the Euclid Space Telescope. 00:16:55.320 --> 00:16:58.299 Oh, Euclid is amazing. An observatory literally 00:16:58.299 --> 00:17:01.019 parked in space, free from the blurring effects 00:17:01.019 --> 00:17:03.779 of Earth's atmosphere, utilizing massive digital 00:17:03.779 --> 00:17:05.859 sensors. It's like drawing a landscape from a 00:17:05.859 --> 00:17:08.500 blurry memory versus looking at a high -definition 00:17:08.500 --> 00:17:11.039 4K photograph. If we connect this to the bigger 00:17:11.039 --> 00:17:13.119 picture, it's about how science builds on itself. 00:17:13.240 --> 00:17:16.099 Yeah. I mean, the rest didn't have the opti - 00:17:15.559 --> 00:17:17.640 to see the gravitational bridges. He certainly 00:17:17.640 --> 00:17:20.460 couldn't see a type ES supernova. But he did 00:17:20.460 --> 00:17:22.740 the most essential thing a scientist can do. 00:17:23.119 --> 00:17:25.839 He formally documented the position. He assigned 00:17:25.839 --> 00:17:28.059 the coordinates. He laid the foundation so that 00:17:28.059 --> 00:17:31.200 160 years later, the Euclid Space Telescope knew 00:17:31.200 --> 00:17:33.779 exactly where to point its cameras. Exactly. 00:17:34.039 --> 00:17:36.099 And the Euclid mission isn't just taking pretty 00:17:36.099 --> 00:17:39.039 pictures. Its primary objective is to map the 00:17:39.039 --> 00:17:42.019 geometry of the dark universe, to understand 00:17:42.019 --> 00:17:44.690 dark matter and dark energy. And how does it 00:17:44.690 --> 00:17:47.630 do that? By looking at the exact kind of structural 00:17:47.630 --> 00:17:50.990 distortion happening to NGC 1268. Oh, because 00:17:50.990 --> 00:17:53.910 dark matter exerts gravity. So to map dark matter, 00:17:54.029 --> 00:17:56.150 you have to look for galaxies that are being 00:17:56.150 --> 00:17:58.609 gravitationally sheared and stretched. Precisely. 00:17:59.109 --> 00:18:02.089 The tidal bridge is connecting 1268 and 1267, 00:18:02.329 --> 00:18:05.130 the warping of that SAB ERS -B spiral structure. 00:18:05.710 --> 00:18:08.309 That morphological damage is a direct tracer 00:18:08.309 --> 00:18:11.109 of the unseen gravitational fields in the Perseus 00:18:11.109 --> 00:18:13.920 cluster. That is so cool. Yeah. By analyzing 00:18:13.920 --> 00:18:17.200 the high resolution images from Euclid, astrophysicists 00:18:17.200 --> 00:18:19.160 can reverse engineer the distribution of dark 00:18:19.160 --> 00:18:21.079 matter that is causing the taffy pole effect. 00:18:21.869 --> 00:18:24.170 DuRest's faint visual smudge has become a crucial 00:18:24.170 --> 00:18:26.609 data point in understanding the fundamental architecture 00:18:26.609 --> 00:18:28.650 of the universe. So what does this all mean for 00:18:28.650 --> 00:18:30.869 you? When you look at a Wikipedia page full of 00:18:30.869 --> 00:18:33.970 raw astronomical data right ascension, declination, 00:18:34.289 --> 00:18:36.309 radio velocity, morphological classifications, 00:18:36.730 --> 00:18:38.930 it's super easy to just scroll past it and dismiss 00:18:38.930 --> 00:18:40.490 it as bookkeeping for nerds. Oh, definitely. 00:18:40.690 --> 00:18:43.930 But hidden inside those dry columns is a violently 00:18:43.930 --> 00:18:46.869 dramatic narrative. It is the story of galaxy 00:18:46.869 --> 00:18:48.809 plunging through the high friction environment 00:18:48.809 --> 00:18:51.890 of the Perseus cluster at over 3 ,000 kilometers 00:18:51.890 --> 00:18:55.579 a second. Yeah It's a story of tidal forces literally 00:18:55.579 --> 00:18:57.940 ripping streams of stars out into the vacuum 00:18:57.940 --> 00:19:01.619 of space like warm taffy. It's the story of parasitic 00:19:01.619 --> 00:19:04.779 white dwarf stars detonating with enough thermonuclear 00:19:04.779 --> 00:19:07.579 force to serve as cosmic firecrackers, allowing 00:19:07.579 --> 00:19:09.720 automated algorithms on Earth to measure the 00:19:09.720 --> 00:19:12.160 scale of the universe. It's a reminder that data 00:19:12.160 --> 00:19:15.279 is never just data. It is the blueprint of a 00:19:15.279 --> 00:19:18.000 fiercely dynamic reality. Right. And speaking 00:19:18.000 --> 00:19:20.400 of that reality, there's one final lingering 00:19:20.400 --> 00:19:23.109 implication in all of this that I just can't 00:19:23.109 --> 00:19:25.670 shake. It comes directly from that distance constraint 00:19:25.670 --> 00:19:29.589 of 147 million light years. Ah, the time delay. 00:19:29.809 --> 00:19:32.029 Because light has a universal speed limit. Looking 00:19:32.029 --> 00:19:34.369 out into the deep cosmos is literally looking 00:19:34.369 --> 00:19:37.009 backward in time. Right. The light we are seeing 00:19:37.009 --> 00:19:40.609 from NGC 1268, the high definition structural 00:19:40.609 --> 00:19:43.069 damage captured by the Euclid Space Telescope, 00:19:43.470 --> 00:19:46.170 the faint 18 .8 magnitude blink of the supernova 00:19:46.170 --> 00:19:49.670 in 2008, the distorted bridges of stars sheared 00:19:49.670 --> 00:19:53.390 off by NGC 1267. None of that is happening right 00:19:53.390 --> 00:19:57.089 now. Not even close. That light took over 147 00:19:57.089 --> 00:19:59.430 million years to cross the void and reach our 00:19:59.430 --> 00:20:01.410 telescope mirrors. Which is mind -blowing. It 00:20:01.410 --> 00:20:04.230 is. Which means the violent interaction we are 00:20:04.230 --> 00:20:06.869 so carefully observing actually occurred during 00:20:06.869 --> 00:20:08.690 the late Jurassic period here on Earth. Wait, 00:20:08.750 --> 00:20:11.339 really? Yes. While stegosauruses were walking 00:20:11.339 --> 00:20:13.339 around, the photons carrying the image of that 00:20:13.339 --> 00:20:15.920 supernova began their journey. That is deeply 00:20:15.920 --> 00:20:18.039 unsettling to think about. So I want you to consider 00:20:18.039 --> 00:20:19.640 this the next time you look up at the night sky 00:20:19.640 --> 00:20:22.019 toward the constellation Perseus. Given that 00:20:22.019 --> 00:20:26.000 NGC 1268 has a verified radial velocity of over 00:20:26.000 --> 00:20:29.519 3 ,200 kilometers per second, and given that 00:20:29.519 --> 00:20:32.079 it is locked in a violent destructive high -friction 00:20:32.079 --> 00:20:35.180 collision course with its neighbor, What does 00:20:35.180 --> 00:20:37.660 intersea 1268 actually look like right this very 00:20:37.660 --> 00:20:39.980 second? It's entirely possible the tidal bridges 00:20:39.980 --> 00:20:42.660 have been completely severed The two distinct 00:20:42.660 --> 00:20:45.519 galaxies could have finished their orbital dance 00:20:45.519 --> 00:20:49.079 and merged into a single, massive, unrecognizable 00:20:49.079 --> 00:20:51.940 elliptical structure. The spiral arms, the central 00:20:51.940 --> 00:20:54.380 bar, the inner ring we classified so precisely, 00:20:54.839 --> 00:20:56.700 they could all be completely gone. The physics 00:20:56.700 --> 00:20:59.019 dictate that it has almost certainly undergone 00:20:59.019 --> 00:21:02.019 a radical transformation. The data profile we've 00:21:02.019 --> 00:21:04.619 been decoding today is effectively a historical 00:21:04.619 --> 00:21:07.799 document. We are studying the ghost of a collision. 00:21:08.019 --> 00:21:10.279 And it is a mystery. We won't know the actual 00:21:10.279 --> 00:21:13.700 present date. answer to for another 147 million 00:21:13.700 --> 00:21:17.460 years. 147 million -year -old ghost of a collision. 00:21:17.700 --> 00:21:19.980 Mm -hmm. It really recontextualizes that opening 00:21:19.980 --> 00:21:22.000 thought, doesn't it? It really does. When Heinrich 00:21:22.000 --> 00:21:24.839 Duress peered through his eyepiece in 1863, he 00:21:24.839 --> 00:21:26.559 thought he was finding a peaceful patch of light 00:21:26.559 --> 00:21:29.099 in a calm clockwork universe. He had no way of 00:21:29.099 --> 00:21:31.440 knowing he was staring at a chaotic brawl hidden 00:21:31.440 --> 00:21:33.859 behind neat and tidy coordinates. So the next 00:21:33.859 --> 00:21:35.980 time you expect things to be clean, static, and 00:21:35.980 --> 00:21:39.240 easily categorized, remember the violent ever 00:21:39.240 --> 00:21:41.440 -changing reality of NGC 1268.