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

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"):

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👩🏽‍💻 Dr Becky Smethurst is an astrophysicist researching galaxies and supermassive black holes at Christ Church at the University of Oxford.

[conors]

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

[DirtyRobot]

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

[Azameanie]

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. 👍👍

[cowboyfrankspersonalvideos]

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.

[archaurore]

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.

[bobcabot]

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...

[brodaclop]

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.

[knucklecorn]

Interesting ✔
Good audio ✔
In focus ✔

[calyodelphi]

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. <3

[vencislav_krumov]

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.

[renaudkener]

Super massive "THANK YOU" for this video

[kingWesternTube]

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

[Tritium]

What a fantastic story of science, well put together.

[BIGVN]

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

[davidlillo]

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. 🥰🥰🥰

[Flexible_photon]

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.

[scottwatrous]

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.

[zapfanzapfan]

Wait, you got a PhD at 26? Damn! :-)

Very nice history lesson!

[shezcop]

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

[noelwade]

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!