Black Hole Swarms | Space Time

  • Published on: 25 April 2018
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    It’s been conjectured that the center of the Milky Way is swarming with tens of thousands of black holes. And now we’ve actually seen them.

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    Previous Episode:
    Using Stars to See Gravitational Waves

    This episode of Space Time Journal Club looks at the paper:

    A density cusp of quiescent X-ray binaries in the central parsec of the Galaxy
    by Hailey, Mori, Bauer, Berkowitz, Hong & Hord (2018)

    The core of our galaxy is a wild place. The stars are so densely packed that the night sky would be 500 times brighter. A supermassive black hole, 4 million times the mass of our Sun lurks in the center. It flings nearby stars into extreme slingshot orbits. It consumes anything that gets too close is consumed, burping a blast of X-rays. We know these things because we see them from our comfortable vantage point 28,000 light years out in the galactic disk. But there’s one particularly terrible feature of the core of our galaxy that, until now, has only been has only be hypothesized: The central few light years of the Milky Way is thought to contain a vast swarm of smaller black holes that have rained in from the surrounding galaxy.

    Hosted by Matt O'Dowd
    Written by Matt O'Dowd
    Graphics by Grayson Blackmon
    Assistant Editing and Sound Design by Mike Petrow and Linda Huang
    Made by Kornhaber Brown (

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  • Runtime : 11:32
  • milky way BLACK HOLE galaxy stars bright mass sun swarm journal club


  • GLaDOS
    GLaDOS   4 days ago

    Neo granzon wants to know your location

  • Michael Kaba
    Michael Kaba   3 weeks ago

    Would neutron stars also migrate to the center?

  • Business Chicken
    Business Chicken   1 months ago

    This guy REALLY has a talent for taking something as crazy and exciting as a swarm of black holes, and making it into the most boring and unexciting thing you've ever heard of. I just watched this whole video and literally could not repeat back to you a WORD he said before "Thanks to curiosity stream for sponsoring this video blah blah Patreon blah.". The only time he showed any real enthusiasm at all was at the end in a prerecorded sponsorship ad.Edit: I used to LIKE physics..

  • Murfie's law Defined
    Murfie's law Defined   1 months ago

    If han would've used one of theese he coulda made the kessle run in 10+2 parsecs

  • Nathan Wilson
    Nathan Wilson   1 months ago

    The black hole swarm sounds like the name of an emo band haha. Stay well out there everybody, and Jesus Christ be with you friends.😊

  • Tom's Ghost
    Tom's Ghost   2 months ago

    so... it's an infestation... call rentokill.

  • Carl Follaco
    Carl Follaco   3 months ago

    Black hole swarm, won’t you come. Wash away the rain. Black hole swarm won’t you come. Won’t you come......

  • James Ladd
    James Ladd   3 months ago

    so are the black holes at the center of the galaxy also moving, or is the idea something like that type of motion is actually from the expansion of space?

  • Johannes Faller
    Johannes Faller   3 months ago

    4:22 can you elaborate on why there must be ancient black holes? What is the general stellar population of these globular clusters? What implies the existence of a large number density of black holes in the clusters?

  • Physics_Hacker
    Physics_Hacker   4 months ago

    I can hardly imagine the black hole insanity near the center of IC 1101

  • jamie
    jamie   4 months ago

    The Maw. Easily handled by the Milineum Falcon. She may not look like much, but she's got it where it counts.

  • Jason Wood
    Jason Wood   4 months ago

    This is what I’m talking about!Never even heard of this before today. Thank you!

  • shadowhawk
    shadowhawk   4 months ago

    They all have to orbit something.

  • thereal sayonara
    thereal sayonara   5 months ago

    Isnt all this inference? Where does dark matter fit in with observable inferences?No tryin' to be a jerk, you guys are way smarter than me.

  • Rock Brentwood
    Rock Brentwood   5 months ago

    That's about the same part of the galaxy where Coruscant would be. That might explain the problem they were having with the Dark Side.

  • Travis Hayes
    Travis Hayes   5 months ago

    i love reading text as someone reads it to me. wtf who taught you how to do presentations.

  • En théo
    En théo   5 months ago

    If a black hole can be slowed down by draging smaller objects on its path, all things being equal, is there not as much chance for that black hole to meet objects that move faster and therefore be dragged by them ?

  • SnowblindOtter
    SnowblindOtter   5 months ago

    Good luck seeing the Milky Way anymore if you're able to reliably watch this video.

  • Richard J
    Richard J   5 months ago

    I love this video! Thank you 🙏😊

  • Jenny Tokumei
    Jenny Tokumei   5 months ago

    So stars that are big enough to become black holes are elves. And like elves, they don't die, they just head off for the land of Summerset, only it's not Summerset, it's the center of the galaxy.

  • morelenmir
    morelenmir   5 months ago

    This was an excellent, level-headed presentation of information without any of that horrible jump-cut-every-other-word style that absolutely fills YouTube.

  • Ken S
    Ken S   6 months ago

    Somehow 28,000 ly doesn't seem far enough away anymore.

  • Pavan Kumar
    Pavan Kumar   6 months ago

    Is a Black hole formed in outer layer of milkyway have a chance of interacting with solar system on it's way to the center.

  • Josef Navrátil
    Josef Navrátil   6 months ago

  • Brendon Saunders
    Brendon Saunders   6 months ago

    Bring back the guy who looks like Joe from impractical Jokers

  • San
    San   7 months ago

    They do move in herds...

  • Brent Caldwell
    Brent Caldwell   7 months ago

    Umm. Is it just me or is a black hole swarm literally the most terrifying concept imaginable???

  • Florin Olariu
    Florin Olariu   7 months ago

    Two opposite spinnig black hole with the same mass, cancel eachother?

  • Florin Olariu
    Florin Olariu   7 months ago

    Can you stop still in space, and let the spin of the galaxy bring the stars to you?

  • Gustavo Valdiviesso
    Gustavo Valdiviesso   7 months ago

    This video became relevant again, and YouTube's algorithm knowns it, because it came back to the feeds. Look for the new paper explaining why LIGO sees so many BH collisions.

  • Yours Truely
    Yours Truely   7 months ago

    Show me your black hole..We keep seeing the gravitational waves...... Pfff.A cosmic wave of nutron stars.. You are smoking black holes again?

  • enlightened advocate
    enlightened advocate   8 months ago

    I feel like such a bad person. I can never listen to this guy. I dont know if its the hand gestures, voice, facial expression, or what but something kills me. Like hes trying way to hard to let me know hes talking about something deep or interesting.

  • ND Put
    ND Put   8 months ago

    How come the swarm doesn't eventually merge into one single SMBH? I mean a swarm with that many BH's must eventually merge, right?

  • YouTube Acct
    YouTube Acct   8 months ago

    Why does dynamical friction cause a Stellar Mass black hole to do something different than a Stellar Mass star? How are these 2 objects different beyond their SIZE/RADIUS?In fact Wikipedia says it acts the same on all objects (not just black holes). So shouldn’t all stars end up in the center eventually?Your explanation here only spreads the wrong idea about black holes. They are hardly special compared to any other massive object, except for their size.

  • Sphinx Rising
    Sphinx Rising   8 months ago

    One major problem with this swarm concept. Using radar & other means, we have mapped the orbits of central stars, & they all revolve around a central point. If there was many massive black holes, there would be chaos at the central part of the galaxy, which there is not.

  • antiisocial
    antiisocial   8 months ago

    I can't see the Milky Way. I live in a city of millions...😥👎