How do we know there's a black hole in every galaxy centre?

How do we know there's a black hole in every galaxy centre? | History of Supermassive Black Holes

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At the centre of every galaxy, there is a supermassive black hole (a million to a billion times bigger than the Sun). But how do we even know that? There are so many scientific results that have jigsaw-pieced together throughout the past century that allow us to know that now, so join me, as I go through decade by decade and explain the significance of all the results that have built up the big picture.
00:00 - Introduction
00:53 - 1900s
03:58 - 1910s
05:50 - 1920s
06:58 -1930s
09:04 - 1940s
11:00 -1950s
12:09 -1960s
17:14 - 1970s
18:38 - 1980s
19:40 - 1990s
22:12 - 2000s
23:28 - 2010s
Here are links to all the papers I mentioned throughout the video, again listed by decade (note that "et al." is Latin for "and others"):
Michell (1784) - royalsocietypublishing.org/do...
Fath (1909) - articles.adsabs.harvard.edu/pd...
Einstein (1915) - en.wikipedia.org/wiki/List_of...
Schwarzschild (1916) - commons.wikimedia.org/wiki/Fi...
Lemaître (1927) - articles.adsabs.harvard.edu/pd...
Hubble (1929) - www.pnas.org/content/15/3/168
Einstein (1931; cosmological constant introduced) - echo.mpiwg-berlin.mpg.de/ECHOd...
Chandrasekhar (1931) - articles.adsabs.harvard.edu/pd...
Tolman (1939) - journals.aps.org/pr/abstract/...
Oppenheimer & Volkoff (1939) journals.aps.org/pr/abstract/...
Seyfert (1943) - articles.adsabs.harvard.edu/pd...
Bolton, Stanley & Slee (1949) - www.nature.com/articles/164101b0
Baade & Minkowski (1954) - articles.adsabs.harvard.edu/pd...
Burbidge (1959) - articles.adsabs.harvard.edu/pd...
Minkowski (1960) - articles.adsabs.harvard.edu/pd...
Giacconi (1962) - journals.aps.org/prl/abstract...
Hoyle & Fowler (1963) - articles.adsabs.harvard.edu/pd...
Schmidt (1963) - www.nature.com/articles/19710...
Kerr (1963) - journals.aps.org/prl/abstract...
Salpeter (1964) - articles.adsabs.harvard.edu/pd...
Zel’dovich (1964) - ntrs.nasa.gov/search.jsp?R=19...
Schmidt & Matthews (1964) - articles.adsabs.harvard.edu/pd...
Schmidt (1965) - articles.adsabs.harvard.edu/pd...
Penrose (1965) - journals.aps.org/prl/abstract...
Hawking (1967) - www.jstor.org/stable/2415769?...
Hewish, Bell et al. (1968) - www.nature.com/articles/217709a0
Lynden-Bell (1969) - www.nature.com/articles/223690a0
Lyden Bell & Rees (71) - articles.adsabs.harvard.edu/pd...
Wolfe & Burbidge (1974) - articles.adsabs.harvard.edu/pd...
Bardeen, Carter & Hawking (1973) - link.springer.com/article/10....
Bekenstein (1973) - journals.aps.org/prd/abstract...
Balick & Brown (1974) - articles.adsabs.harvard.edu/pd...
Sargent et al. (1978) - articles.adsabs.harvard.edu/pd...
Dressler (84) - articles.adsabs.harvard.edu/pd...
Kormendy (88) - articles.adsabs.harvard.edu/pd...
Harms et al. (1994) - articles.adsabs.harvard.edu/pd...
Miyoshi et al. (1995) - www.nature.com/articles/373127a0
Urry & Padovani (1995) - arxiv.org/pdf/astro-ph/950606...
Faber et al. (1997) - articles.adsabs.harvard.edu/pd...
Magorrian et al. (1998) - arxiv.org/pdf/astro-ph/970807...
Ferrarse & Merritt (2000) - arxiv.org/pdf/astro-ph/000605...
Gebhardt et al. (2000) - arxiv.org/pdf/astro-ph/000628...
Hopkins et al. (2006) - arxiv.org/pdf/astro-ph/050639...
Simmons, Smethurst & Lintott (2017) - arxiv.org/pdf/1705.10793.pdf
Martin et al. (2018) - arxiv.org/pdf/1801.09699.pdf
---
📚 My book: "Space at the Speed of Light" is now available in the USA & Canada! www.penguinrandomhouse.com/bo...
📚 For anywhere else in the world you can buy my book here (Space: 10 Things You Should Know - same book, different title) here: bit.ly/SpaceDrBecky
---
👩🏽‍💻 Dr Becky Smethurst is an astrophysicist researching galaxies and supermassive black holes at Christ Church at the University of Oxford.
drbecky.uk.com
rebeccasmethurst.co.uk

Пікірлер: 1 100

@conors4430 4 жыл бұрын

I love how you explain how peer reviewed science builds on itself. It’s something so many people don’t get to see the importance of

@ramchandradey4059 3 жыл бұрын

Without knowledge of indian philosophy in particular and world philosophical thoughts in general neither science nor religion nor any other system of thoughts can wholly comprehend and explain the basic principles of reality as we are yet to conceptualize both the latent and manifest potency of humanity

@Z-add 3 жыл бұрын

How did einstein came up with general relativity. Whose research did he build on?

@nnaammuuss 3 жыл бұрын

@@Z-add Well, not a physicist here, but I gather that the constancy of the speed of light in spite of relative motions, as well as some cosmological discrepancies (were known and) were already being discussed which he factored in. To quote concrete pieces of theoretical works, the 4-dimensional Minkowski spacetime was long derived, tensors, tangent-bundles and stuff well studied in mathematics both by algebraists and analysts, and more recent works by Poincaré on topological spaces to help _patching up_ general geometric objects piece by piece through one seamless framework were available to him, and in deed, sources say, motivated him. Not trying to infer that absolutely original research can't be done though. 👍

@Famous_Mist 2 жыл бұрын

How right you are. Because without it the path was open for flat earthers and other idiots

@bored78612 2 жыл бұрын

@@ramchandradey4059 People like you are so embarrassing man. Stop tooting your own horn acting like you are super smart when you clearly know nothing.

@DirtyRobot 5 жыл бұрын

Did not notice any editing. Just sounded like someone talking for 25 minutes about something they were very passionate about. So, 10/10 filming, 10/10 editing, 10/10 concept and execution, 10/10 story/information, 10/10 for the lead demonstrating an awesome way to communicate. 10/10

@kimghanson 4 жыл бұрын

I thought you were exaggerating but it really is 25 minutes. Seemed like about 7 or 8 minutes. A sign of an outstanding teacher.

@radioactivet-rex286 3 жыл бұрын

Also 10/10 cuteness

@DirtyRobot 3 жыл бұрын

@@radioactivet-rex286 Unfortunately I had to unsubscribe due to her BLM advocacy.

@StanColson 3 жыл бұрын

Theory piled upon theory piled upon made up stuff. If you can't explain stuff, just fabricate (invent) a new thing like Dark Matter, or like Dark Energy, or Darth Vadar, or Dark Light, or Anti Light, or Anti Gravity, or Anti Big Bang. What a bunch of bunk these guys have constructed in order to keep themselves funded by clueless politicians or Anti-politicians (whichever lights your lava light). It is a religion really, but one that is ever changing, evolving, expanding, or anti-expanding ?? Maybe its a 'Dark Religion' ??

@dbaker3751 3 жыл бұрын

I noticed an edit at the 8:02 mark.

@Azameanie 5 жыл бұрын

Your histories of astronomy and astrophysics are your most interesting and most important episodes. More than just name dropping, you demonstrate that even the giants of the field, Hubble, Einstein, Hawking, all worked incrementally. They added pieces to a puzzle begun by men and women long before them, and still incomplete. These were always my favorite episodes of Cosmos (both of them). It’s inspirational as hell. 👍👍

@cowboyfrankspersonalvideos8869 5 жыл бұрын

Great history lesson. Having been born in 1952, I feel privileged to have lived from just after the realization that the Milky Way isn't the entire universe, through the Hubble Deep Field photos, the discovery of supermassive black holes and the discovery of gravitational waves. My biggest cosmological regret is I probably won't live long enough to see what discoveries come from the future LISA program.

@danielthesantos 5 жыл бұрын

HAH! Well that makes me -18 years older than you!! =D To be honest, I don't understand how they are going to manage that in space (LISA), but I can only imagine the discoveries. Plus I would think they would need some super-computing cluster out there to isolate all of the various signals. I'll have to read up more on it, but I don't know if I'll be around for it either! :) Thanks for sharing your perspective though. I would have been born when you were finishing high school, but it's amazing that it was *so recent* that we didn't know about galaxies yet!

@walkingwounded3824 5 жыл бұрын

Well, I am a baby, born in 1964. I am glad I'm not here with only "Genius children". This Dr. Becky is really good at explaining things so anybody could follow. Even an old, beat up rocker like me!@@danielthesantos

@KalRandom 4 жыл бұрын

@@walkingwounded3824 Na I'll be the baby in this chat, 1970. I'm amazed at what has been discovered in my lifetime.

@walkingwounded3824 4 жыл бұрын

@@KalRandom I see I've been replaced! lol

@godsownlunatics9650 4 жыл бұрын

tHE ENTIRE uNIVERSE IS NOT THE ENTIRE UNIVERSE. NO ONE KNOWS WHAT'S BEHIND THE SUN LET ALONE 3 SHIFTS OVER SURPRISES ARE INEVITABLE

@knucklecorn 5 жыл бұрын

Interesting ✔ Good audio ✔ In focus ✔

@papinkelman7695 5 жыл бұрын

Dr Becky ✔

@danielthesantos 5 жыл бұрын

LOL! In focus or not, I love them. I just thought the other one was an artistic interpretation? ;)

@erictaylor5462 5 жыл бұрын

I agree. But the lighting is a bit off. She looks like a Smurf. But who cares about the color of the lighting when her content is so engaging?

@katchou1337 4 жыл бұрын

@bobcabot 5 жыл бұрын

Congrats: You got the rare talent of explaining (really) complex things in an easy manner! ...cant wait to see you delve deep into the controvertial stuff...

@Tuning3434 5 жыл бұрын

You know that Dr. Becky is a regular in _60 symbols_ and especially _Deep Sky Videos_ ? I was kinda surprised she had her own channel, but I don't need Brady to enjoy her expositions.

@bobcabot 5 жыл бұрын

@@Tuning3434 I did not know that! ... she is just brilliant on her own ( better for her talent i guess ) ...

@danielthesantos 5 жыл бұрын

@@Tuning3434 Brady hurt my feelings when he didn't do a video after the media release of the neutron star merger. I was so excited to see some deep sky videos on it. That was truly a revolutionary moment, the beginning of multi-messenger astronomy. Sorry for my off-topic lament! :)

@renaudkener4082 5 жыл бұрын

Super massive "THANK YOU" for this video

@aidanjt 5 жыл бұрын

I see what you did there!

@Pradipawa 5 жыл бұрын

Hmm.. really massive

@RalphDratman 4 жыл бұрын

Be careful with that much mass! Safety first.

@erictaylor5462 4 жыл бұрын

Do you think it's 4 or 5 billion solar masses?

@archaurore3323 5 жыл бұрын

I loved how you discussed the discovery of super massive black holes and how you finished with current research (including your own). As a very little girl (age 6) I went through my father's astronomy magazines and I remember very clearly how there was a flurry of articles about quasars and what they could possibly be. I think one of the most outlandish theories was that it was a star cluster or even a galaxy full of neutron stars. This was back farther than I'm willing to admit. It was only around the mid-80s or early 90s that I remember the super massive black hole theory being proposed in the popular Press.

@PuzzleQodec 5 жыл бұрын

I remember an article I read as a kid that quasar were so bright, they must be white holes. Which was a fun read but I found it hard to believe. My main conclusion was that nobody had a clue so people felt free to speculate away.

@quietyard8014 3 жыл бұрын

Yeah it seems what we read then was like 10-20 years out of date.

@vencislav_krumov 5 жыл бұрын

Thank you, Dr. Becky for making an entire film on the same subject as my a bit overdue assignment on the History of Astronomy course at my Astronomy master's program.

@DrBecky 5 жыл бұрын

Vencislav Krumov 😂 you’re welcome - just don’t forget to reference me!

@Hailfire08 5 жыл бұрын

Hmm, what are the chances, eh?

@brodaclop 5 жыл бұрын

I really appreciate how you managed to put across (despite video being a linear medium) the idea that the path leading to our current understanding isn't so much of a path, but a constantly branching and merging network of discovery, with dead ends, U-turns and sudden leaps of faith that then had to be connected back to the rest.

@calyodelphi124 5 жыл бұрын

I just love the enthusiasm and the energy you have with astronomy and cosmology. You're the kind of scientist we really need in this world.

@mountdrinan1 4 жыл бұрын

@Carlos Saraiva she is NOT a scientist though. Scientific method cannot be performed in her area. She is what’s known as a pseudoscientist

@mountdrinan1 4 жыл бұрын

@Carlos Saraiva I never do drugs so no. google “scientific method” . Now tell me how astronomy gets past the first stage of five. Yes. They can observe a phenomenon but I wait with baited breath as to how you think they can proceed through the remaining four 100% required stages. They are the dictionary definition of Pseudoscience....

@mountdrinan1 4 жыл бұрын

Nah. I know I am clever. My assertion that astronomy is junk science is Sound and unchallenged. Good day

@bldtv7038 4 жыл бұрын

Carlos Saraiva 3 fallacies in one post. ad hominem , baseless assertion and a hand wave dismal. Do you care to tell me how astronomy follows the scientific method or do you want to hilariously give me more of your fallacy examples. I’m waiting

@bldtv7038 4 жыл бұрын

Carlos Saraiva , ok with the weakness of that reply are you about to concede or are you going to tell me how astronomy follows the scientific method ? I’m going to hold your toes to the fire until you answer this so no more weasel replies. Answer the question Einstein wannabe

@Tritium8 5 жыл бұрын

What a fantastic story of science, well put together.

@Chew1964 5 жыл бұрын

Yep! I added it to my favorites.

@kingWesternTube 5 жыл бұрын

I really enjoyed getting some of the backstory. Please consider doing more videos like this.

@BIGV1N 5 жыл бұрын

Dr. Becky, you are my favorite astronomer EVER! I get excited whenever I see a new video from you!

@davidlillo3392 3 жыл бұрын

Your intro statement is exactly why I fallow you. You give the background and take everything full circle until you get to where we are now and what questions we still have. 🥰🥰🥰

@scottwatrous 5 жыл бұрын

This is the kind of knowledge we need. Love hearing about the evolution of understanding. I would watch a similar episode on our understanding of stars in general. It's crazy how I don't remember our understanding of this being different while growing up in the 90s. I remember drawing black holes on my homework because the quasars are just so cool looking. I just assumed we knew that they were black holes for decades. But turns out it was fresh, and I was just too young to have any other knowledge. Also hearing you were born in the 90s is making me feel old as a late-80s baby. Like, holy cow, people born then already can be doctors of science studying black holes! Also is that your diploma there? It looks so cool.

@Flexible_photon 5 жыл бұрын

Very well done. Being 45 I remember reading about "possible" black holes back in the early 80s when I was a kid. I also remember quasars. it's interesting to see how all this fit together because it answered a lot of questions that I've had over the years. Thank you so much for filling in those spaces.

@noelwade 5 жыл бұрын

Wonderful video! It takes a ton of effort to develop a good explanation on any topic - much less a story told over 100+ years by a variety of contributors. Thanks for putting in all of the effort, and gifting us this great presentation!

@shezcop4987 5 жыл бұрын

Great how you put in the bloopers at the end. Thoroughly enjoyed this. I Subscribed immediately. Don't ever stop.

@zapfanzapfan 5 жыл бұрын

Wait, you got a PhD at 26? Damn! :-) Very nice history lesson!

@realitycheck3363 5 жыл бұрын

Yea, apparently PHD's are not what they used to be.

@vikingsoftpaw 5 жыл бұрын

@@realitycheck3363 Or may she's really bright!

@dreamdiction 4 жыл бұрын

@@vikingsoftpaw they give PHd's to anyone who agrees with all the previous bullshit.

@than217 4 жыл бұрын

Whenever she said how old she was I took a good long look in the mirror. Pondered what I've done with my *cough* _35 years_ *cough*

@dreamdiction 3 жыл бұрын

@Open Skies Science has become a belief system, like religion. There is no evidence that relativity happens anywhere other than in the mind of the person thinking about it, there is no evidence that photon particles exists anywhere other than in the mind of the person thinking about them, there is no proof that black holes exist, there is no scientific proof of cosmic inflation (big bang). Physics is real but cosmology is imaginative speculation, like religion.

@bmenrigh 5 жыл бұрын

The quality of your content is going way up. This video was fantastic. Good research, great presentation.

@grayaj23 4 жыл бұрын

THIS was for me your most fascinating video I've seen yet. Every bit of it was interesting and the history with the names and times was terrific.

@67comet 5 жыл бұрын

Improving every time you post a new video. Keep up the good work, listening to your explinations about all things Astrophysics is wonderful.

@dutubsucks 5 жыл бұрын

Your passion for this and your joy in sharing it is fantastic. You also have a great balance in how in depth you go with every step. This was a great watch. Thank you!

@gasdive 5 жыл бұрын

Great video thanks. Love that Feynman always seems to pop up somewhere!

@MendTheWorld 4 жыл бұрын

gasdive I wish "polymath" weren't such a goofy sounding word for describing someone like Feynman, but he truly was one.

@Chew1964 5 жыл бұрын

The best, most concise history of astrophysics on the webs. Thank you.

@thomaswolfe9539 3 жыл бұрын

This channel is fantastic. Love that you don't skim over the details, but also focus on the big idea's from each observation / discovery to prevent from going into too much detail. Thank you!

@Biomirth 5 жыл бұрын

This is so so good Becky! I've never seen anything like it that takes us quickly and precisely through the understanding of galaxy cores over a century or research. If the BBC or NBC were to call you to redo this for them it would probably take 10 episodes and yet you condensed the material here in such a way as to be perfectly comprehensible for someone intermediate in understanding of astronomy. I had bits and pieces of this knowledge beforehand and now I have a strong sense of the research progression. As you said at the beginning it's a strange and almost miraculous thing that you can casually mention that of course all galaxies have a black hole at the center. The journey of this knowledge is such a testimony to the power of collaborative research over time it must rank up there with the best of the best of scientific discoveries that only happen over time.

@richtaylor6039 5 жыл бұрын

Discovered you videos this rainy Saturday afternoon. Very enjoyable, looking forward to your book in September. :-)

@DrBecky 5 жыл бұрын

Thanks Rich 👍 hope you like it when it comes out!

@BoldrepublicRadioShow 5 жыл бұрын

I was having fun watching your notes move around, change pages, and even vanish and come back, as you spoke.

@AlexPronovealexcooper1 3 жыл бұрын

The historical perspective you paint is the best part of your narrative and I notice you do it in many of your videos. That's what differentiates your videos from the others. You have secured that niche. Well done, Dr Becky.

@payday510 5 жыл бұрын

Thanks for taking the time to do this. It's always great to hear experts discuss subjects they're passionate about. Can't wait for more :D

@markmaurer6370 5 жыл бұрын

I think that this kind of historical focused science teaching is especially important for skeptical laypeople. You can list lots of facts about the cosmology of the universe, and I can list a bunch of facts about the Star Wars universe, and some of them would sound very much like your facts. Facts are easy to dismiss especially because fan based trivia is also rational and consistent, but totally fabricated. We're constantly bombarded with nakedly fictitious facts. Telling the human narrative is not only compelling teaching, it helps make science accessable to the emotional and sympathetic part of our psyches. Maybe a misstep for scientist, but very important for laypeople who might have suspicion born of ignorance.

@asshatteryengaged813 5 жыл бұрын

@Mark Maurer : Very well said - I could not agree more. I'd only like to add that science has not nor will ever be infallible in the conclusions it draws. However, as more evidence/observation is accumulated, science self corrects and evolves. It's an incremental process that takes time. @Dr. Becky : Just think, two years ago right now you were scrambling to complete your PhD. Congrats on your accomplishment back then, and we look forward to your many contributions to human knowledge in the future. Thank you again for these videos.

@pseudorandomly 5 жыл бұрын

@Mark Maurer Not only does historical context assist those "who might have suspicion born of ignorance", it's also useful to answer the often-heard layman's question, "How do we _know_ that?" The answer is often, as in this video, a very long chain of observation, analysis, and confirmation. It's useful to be able to tell the story in this fashion, at least in a rough way, so they get the idea that this is evidence-based conclusion, rather than simply being made out of whole cloth.

@tetsi0815 5 жыл бұрын

Exactly! How often I met people who were convinced that for example Einstein sat at his desk just making everything up and then postulating it to the world. Once you explain to them that Einstein actually tried to explain experiments that had been done and that did not agree with the known physics of the time and that a lot of people actually contributed to / shaped his ideas they understand why we know, what we know and especially why scientists can - even if they don't know the 'correct' explanation - rule out wrong answers. It becomes less arbitrary to them at that point.

@e1123581321345589144 5 жыл бұрын

Totally agree. It's nice to see how the understanding of a concept evolves over time. When debating scientific discoveries I often bump into people who don't understand the scientific process and think everything is just in a theoretician's mind.

@grayaj23 4 жыл бұрын

I agree. What I find the most compelling is that you can take a slightly difference "slice" of science and a lot of the same names linked to the same ideas will appear there as well. This mesh of ideas spans across the entirety of modern science and it becomes clear that if some little obscure prediction from way back in 1914 had been wrong, smartphones as we know them would not exist. The fact that a PET scanning device even *exists* reinforces the standard model of particle physics. The basic function of television is inextricably linked to how LEDs operate at subatomic scales. "That thing you're holding in your hand, with the video screen, condenser microphone, filmless camera, speakers, GPS and motion-detection all by itself demonstrates just about the entirety of the science that you're scoffing at."

@InfiniteRegress 5 жыл бұрын

This is excellent, Dr. Becky! ^_^ If you don't mind, I have a couple of black hole questions for which I haven't been able to find any answers anywhere (and I've really looked!). Why does anyone think anything can fall past an event horizon at all? Since time is flowing more slowly closer to the event horizon than it is farther from the event horizon, surely nothing in the entire history of the universe has ever crossed any event horizon, right? When it comes to relative motion, there is of course no preferred reference frame (although I would say the CMB is the best candidate), but when it comes to relative positions and gravity wells, wouldn't a reference frame with a faster flow of time farther from gravitationally induced time dilation effects be the one whose perspective "overrules" a slower one? Black holes could still grow because, while stuff that does fall toward a black hole could never cross the event horizon, the black hole together with the infalling stuff would then define a new, wider event horizon that later infalling objects could never cross, and so on. Black holes would effectively be event horizon onions! And wouldn't this also mean that singularities are impossible to form, too? As something compresses toward being within its own Schwarzschild radius, time moves more and more slowly for it relative to the surrounding universe; so, for example, the flow of time for a stellar core or neutron star that is collapsing into a black hole should just asymptotically become slower and slower, and since the frame of reference that gets to say what is "actually happening" should be the faster one, no black holes anywhere "actually" contain singularities--only an original, increasingly slow "seed" around which are the layers of newer event horizons. That was supposed to count as just one question, hah. :P My other question is about supermassive black holes and a process by which they might have formed. I've read about the direct collapse process by which the essentially zero metallicity gas of the early universe might have allowed for the formation of "stars" that were many tens of thousands of solar masses but almost seamlessly continued collapsing past that stage into supermassive black holes. I was wondering if, instead of by way of some sort of collapse, supermassive black holes might just be solar system scale regions of space where a couple hundred million or so stellar mass black holes and neutron stars happened to gather, pushing that region to its Schwarzschild density. A 1 billion solar mass black hole has an event horizon radius of almost 20 AU, which means that its density is less than 20 kilograms per cubic meter, or 50 times less dense than water. Having 333 million 3 solar mass black holes in that region would still allow for almost 15 lightseconds worth of distance between black holes. So, how plausible--in terms of time for the Population III stars to create a bunch of stellar mass black holes that could then collect toward a central region--is it that supermassive black holes could have formed this way? In other words, if we had magic vision that allowed us to look inside of supermassive black holes, we'd see a whole asymptotically slowing swarm of stellar mass black holes. Thanks in advance! ^_^

@lesconrads 5 жыл бұрын

Your audio and video did make a huge jump here - amazing! Thanks for spending the time to explain your field to the public.

@skyrockit8271 5 жыл бұрын

BEST VIDEO YET DR BECKY ! ! ! So much wonderful background and history ~

@carlg5086 5 жыл бұрын

Dr Ph.D Astrophysics certificate in the background.... Winning! 👍🏻🇬🇧

@Malandirix 5 жыл бұрын

Really great video and presenting. Even rivaling those who've done it for years I think.

@peanut12280 Жыл бұрын

Great content, Dr. Becky. I love listening to your episodes because I feel I always learn something. And you do it while just being you.

@williamtessier5449 5 жыл бұрын

Your channel has become my favorite on youtube. I look everyday for something new form you, knowing it will be most interesting, and i love that. You are young and you present it in a fresh way every time. Please keep up the GREAT work.

@philbuglass4857 5 жыл бұрын

Very interesting stuff... I knew a lot of this already, but not the historical context. Also, thanks for showing the photographs of the scientists! Interesting to put faces to some of the names we hear all the time. Be honest, readers, how many people would have recognised *anyone* other than Einstein?

@volkerbuescher 5 жыл бұрын

Feynman, Hubble, Lemaitre because of his soutane, maybe Oppenheimer...

@aidanlevy2841 5 жыл бұрын

I would have recognized Dr Becky too :)

@philbuglass4857 5 жыл бұрын

Sorry, I forgot Hawking was in there... Still, he is more a contemporary than historical figure, which is probably why it didn't click.

@mal2ksc 5 жыл бұрын

Hawking, Feynman, Zwicky, Bekenstein, and Jocelyn Bell. I'd consider all of them to be on my "I know who that is on sight" list. Probably some of the others just aren't coming to mind right now. Oppenheimer I'd know, but have to think about a little bit. Of those (including Oppenheimer, I know his voice better than his face), I don't have a mental image of Zwicky's voice but I do for the others

@urmeti 5 жыл бұрын

More bloopers, pls ! xD

@blackthorne-rose 3 жыл бұрын

"Flurrin"="flowing" ... "Exactly the same...pretty much.." lol

@Totumfacky 2 жыл бұрын

Thank you for publishing your videos Dr Becky!

@redhaze8080 5 жыл бұрын

That was a really quality vid hey. Great work Becky!

@SpoopyGamer 5 жыл бұрын

*clears throat* YAAAAAAAAAAAAY DR BECKY!!!!

@Carisus 5 жыл бұрын

Totally referring to them as the "tensies" from now on. (tensy's?) (tenzies?)

@pawe3039 5 жыл бұрын

And never by "noughtsies".

@baronet68 5 жыл бұрын

@@pawe3039 I agree... that sounds too much like 1940's European occupation. ;-)

@leslieviljoen Жыл бұрын

This is so fascinating, thanks for putting it together Dr. Becky!

@tdoubt100 4 жыл бұрын

One of the best documentaries I have ever seen! Thank you Dr. Becky! I have watched this three times as the density of information is phenomenal and the history content is sublime. I love the story you weave right up to the present day. Thank you so much for this!!!

@dimitriedgarmetz3147 5 жыл бұрын

Schwarzschild is pronounced: Swarts-shield not ...child or ...chilled as many english speaking say erroneously. Translated from German: Black-Shield Coincidentally appropriate, considering he define the formula for the radius of a black hole, establishing where the event horizon or the 'black-shield' At the event horizon the Time comes to a complete standstill, there's complete length contraction and charge reduction. See my video for the calculation: kzfaq.info/get/bejne/nr99qa2m0p_DdKM.html

@jamesdriscoll9405 5 жыл бұрын

Some papers written during WWI, while he was serving in the artillery

@jwarmstrong 5 жыл бұрын

Dr. Becky your nobel prize in astrophysics is waiting for your paper. Please send by overnight mail.

@mikefriend1514 3 жыл бұрын

One of the great achievements of the modern age of man is the dissemination of scientific learning. And the amazing fact that I seem to have moved seamlessly from knowing bugger all about the universe to suddenly having words like cosmic background microwave radiation, red shift and super massive black holes happily bouncing around in my head as if they always belonged there.

@Dappdude 5 жыл бұрын

That was a great video Becky! :D Love it!

@garethjohn3389 5 жыл бұрын

Excellent video! Interesting fact that I've read before: Karl Schwartzchild calculated the event horizon when he was in the Russian army on the eastern front of WW1 in the trenches!!!

@timkratz742 4 жыл бұрын

He is called Schwarzschild and pronounced Shvahts-shill-d. Has nothing to do with children. Funnily, his name means "black shield" in German which is quite literally what a Schwarzschild-radius looks like.

@zaphod333 Жыл бұрын

@@timkratz742 Being late to the party, it's ˈʃvartsʃɪlt to be precise. 😜 Glad I'm not the only nitpicker.😇 I know it's hard though, and it doesn't make the slightest dent in my appreciation for the channel either.

@blenderpanzi 5 жыл бұрын

Very interesting video! Just one thing: it's not "Schwarzs-Child", it's "Schwarz-Schild". "Schild" being pronounced somewhat like "sheeld". It means black shield. :)

@byrnemeister2008 5 жыл бұрын

Superb video. You are producing some excellent science content. I like all the links to the source papers in the notes. This all must have been a lot of work. Keep it up.

@wavemaker54 5 жыл бұрын

Dr. Becky, that was simply fascinating, amazing, and extremely interesting. Thank you.

@peterbateman74 5 жыл бұрын

Is it fair to say that galaxies are just accretion disks for their black holes? Or am I overstating the importance of the black hole to the galaxy?

@DrBecky 5 жыл бұрын

I'd say that's a fair statement. The galaxy is intrinsically tied to the black hole - any material pushed towards the centre, in theory, will *eventually* end up as part of the black hole

@lachezarkrastev7123 5 жыл бұрын

Those eyes are hypnotizing :)

@nagualdesign 5 жыл бұрын

_facepalm_ You do realize that it's 2019, and that objectifying women makes you look creepy, like Borat or someone from the 1970's, right? You might as well ask her to unbutton her top! She's an astrophysicist and this video is about astrophysics, and you want to comment about how pretty she looks?! Nobody is interested in reading about your sexual proclivities, thanks all the same. Maybe you should think about keeping those kinds of thoughts to yourself.

@lachezarkrastev7123 5 жыл бұрын

I like her eyes, what is your problem?

@MrMbc77 5 жыл бұрын

nagualdesign You clearly don't know what objectification is and you undermine those who are actually objectified.

@nagualdesign 5 жыл бұрын

*objectification* _Woman:_ [Spends 25 minutes talking about astrophysics] _Man:_ You have pretty eyes

@lachezarkrastev7123 5 жыл бұрын

You are pathetic. Anyway, if Dr. Becky is offended my sincere apology! ... but I do not think for a second she has so simplistic way of thinking.

@landrybeck 2 жыл бұрын

I'm so glad I found your channel, Dr. Becky! You make Astronomy and Physics FUN, relatable, and understandable without being condescending about it. There are so many scientists out there with channels who present information with a very smug and high-minded approach. With you, it feels like we're all just hanging out in a casual cafe learning how we believe the universe works. Thank you so much for the quality content.

@cernunnos_lives 3 жыл бұрын

You are amazing. Pure content, passion, and no fluff. Very few can hold this content cohesively to making a great point. History is even brought to the fore! Thanks.

@billb2176 3 жыл бұрын

Geez Becky - just discovered your channel and couldn't be more impressed with the summary of a few decades/centuries - impressive!!!

@AirCommandRockets 5 жыл бұрын

Great video and very informative! Keep up the great work :)

@e1123581321345589144 5 жыл бұрын

Really love this approach. Education on the scientific process is just as important as education in scientific facts. Keep up the great work Rebecca and thanks for this. I know how time consuming these clips can become especially with this amount of research behind them so thank you.

@erikthedragongeek7657 5 жыл бұрын

My new favorite youtuber! Loving these videos already, great work, always been a fan of Astrophysics and Astronomy, kinda runs in my family. Robert L. Staehle, my uncle, and Lori Paul Staehle my aunt are in the field..

@Dovil3334 4 жыл бұрын

Thank you for all the work you're putting in your videos. It is a real pleasure to learn from your videos.

@bimmergeezer 5 жыл бұрын

Thank you for this history lesson. I find it fascinating to see knowledge progressing. You did a wonderful job clearing this up. Keep up the great work!!

@jakubmidera4261 5 жыл бұрын

+1. Nicely shows the process. Breakthroughs and slow evolution of ideas. Great vid.

@garymadden2328 5 жыл бұрын

Excellent again Becky, well told and easy to follow!

@RaumBances 3 жыл бұрын

Excellent video. Thank you so much and congrats for being a part of the discovery and understanding.

@proprotornut5389 3 жыл бұрын

Fascinating video. Really enjoyed this. Great work. 👍

@anthonyoch8285 5 жыл бұрын

Thanks Becky! That was very well put together.

@OldieBugger 5 жыл бұрын

Great video, and it's amazing that you can present these subjects in such a way that even I can understand some of it!

@BillMSmith 4 жыл бұрын

I just recently discovered this channel, and I'm enthralled. I've always wanted to know the back story (of everything), and you seem to be dedicated to providing that with your series. Thank you. Also, I love the way the style of the photographs of the earlier astronomers evolve over time. I wonder what photo of R. Smethurst will be used by future science communicators. If you could leave only the infant pictures for them it would make your achievements seem even more amazing.

@Arfonfree 4 жыл бұрын

I so enjoy the opportunity to bring my knowledge of the universe up to date. Thank you very much.

@Garrett0329 Жыл бұрын

Thanks Dr. Becky Very insightful and makes me ponder

@comatronic 5 жыл бұрын

You are so fun to watch! You are very good at explaining the stuff I love. Binging!!

@martinpickard6043 5 жыл бұрын

Thoroughly enjoyed that timeline explained. Shared this post 😃

@Vicnsi 3 жыл бұрын

19:41 "so at the start of the 90s, first of all I was born..." woohoo, that was the best part! 🙌🏼

@mjaerkens 5 жыл бұрын

Nice and steady subscription growth! Keep it up. Video was really good quality and very explanatory. I wonder how many subscriptions it will take before this channel goes blackhole.

@darkwater234 5 жыл бұрын

I didn't realize you had your own channel! I'm looking forward to catching up on your videos. Subbed!

@martinchambers8090 4 жыл бұрын

Wow, thank you so much for all your superbly informative (and entertaining) videos. I wish I had found them long ago.

@TheSadButMadLad 5 жыл бұрын

History and science together in one video. Wow! Nicely done video with good editing and nicely presented facts. Did I say it was nice. ;-)

@RalphDratman 4 жыл бұрын

Superb teaching and storytelling! Thank you so much, Dr. Becky.

@anushkamunasinghe9673 5 жыл бұрын

Hey Doc, keep the great work going. :) Love your work.

@ValeriePallaoro 3 жыл бұрын

Thanking you for a previous video that I watched in which you explain how the colourisation works on star photos and Im no longer focussed on 'how did they get those colours' but can enjoy the pix for what they are. A late thanks but full hearted non-the-less.

@slayerem 5 жыл бұрын

Adorable! Your passion for your work and your ability to explain it to us, non scientists, surely makes you more than a "tiny" piece in this massive jigsaw that fascinates humanity for over a century now.

@juanstepbehind 3 жыл бұрын

These extended videos are awesome!

@Roush97BC 5 жыл бұрын

Awesome video, thanks for sharing all this great information

@rickwyant 5 жыл бұрын

Great explanation... subscribed and watching all your videos. Thanks.

@Gumby902 5 жыл бұрын

Extremely interesting and informative video. Thanks Dr. Becky.

@grywacz 5 жыл бұрын

Showing context and the history of thought and discoveries, as opposed to just the latest state of knowledge, is how one makes science approachable. Thank you for this great overview.

@patloria1 3 жыл бұрын

Love it! Thanks for that explanation, Dr Becky, of how we got to now on black holes. Were you excited by the photo of the black hole (finally) that was recently published?

@ChampuStrike 5 жыл бұрын

Im glad youtube reccomended me your channel, interesting easy to follow and understand

@peterstrong772 3 жыл бұрын

You are definately the best at explaining how the universe works by our understanding, I have always been confused by the expansion theory, but not since watching you, I look forward to more of your videos, and hope you get more limelight, you deserve it.

@ole9421 5 жыл бұрын

That was an amazing talk, Becky. BRAVO!

@paulrussell1707 4 жыл бұрын

Hi Dr Becky, First of all thank you, you communicate difficult concepts so well that even a high school drop out like me can follow you (i think). I have only come to science and more particularly physics later in life.

@TeddSpeck 5 жыл бұрын

Just want to say thank you for making this Dr. Becky. It's wonderful to follow the history of how we gain knowledge and to see your excitement at being part of it. Just think of all the great things you'll be involved with in the next 40 or 50 years of your career. What will they be? Probably things you can't even imagine now.