The Supermassive Black Hole at the Center of the Milky Way

[Music] did you hear the news astronomers wielding the biggest telescope ever invented the Event Horizon telescope managed to take a snapshot of the monster black hole at the center of our Milky Way galaxy today I'm going to take you on a deep dive into what this means for our understanding of matter gravity and our galaxy itself let's go into the [Music] impossible if you're new to my channel welcome I'm Brian Keon the Chancellor's distinguished professor of physics at UC San Diego I'm an experimental cosmologist who builds telescopes and takes them all around the world from the South Pole to Chile to California and even to far-flung places like outer space today's announcement literally shook up the world not only for professional astronomers like me but for amateurs lay people every curious human being just like you the Event Horizon telescope was constructed in the past 10 years and in 2019 made a stunning announcement the first ever image of the so-called Event Horizon of a black holek black holes are the most mysterious objects in the universe they've been awarded multiple Nobel prizes for discoveries ranging from ligo to the theoretical underpinnings of their mathematical structure to Sir Roger Penrose we've even seen images in the optical and near infrared thanks to telescopes run by Andrea gz and Reinhardt gensel using Adaptive Optics in the infrared wavelength regime today's press conference shook up the universe it showed magnificent images that shed light pun intended you're a funny guy on the most mysterious objects we know about these black holes are the subject of great controversies perhaps responsible for our deepest understanding of how gravity can be unified with quantum mechanics black holes have implications for the destruction of information something that's forbidden by quantum mechanics they have relevance to thermodynamics to entropy and even are understanding of time sometimes black holes are even thought to be the source of dark matter in the universe although we've known for quite some time that black holes can't contribute very much to the amount of Dark Matter there is in the universe even the most massive black hole that we've ever imaged using the Event Horizon telescope in 2019 the black hole at the core of m87 which weighs in at a whopping two billion times the mass of our sun m7's huge black hole Mass makes it really a monster that black hole is dwarfed by almost a trillion more stars in m87 the black hole only represents about. 1.2% of the mass of that particular Galaxy and the same is true of the Milky Way galaxy that today's results pertain to galaxies like the Milky Way actually orbit not because of the black hole at their Center but because of the vast amount of dark matter which far dwarfs the amount of black hole mass in our galaxy in past interviews with hyala and Shep dolman on this channel we discussed the phenomenon of the so-called light Shadow or eventor Riz which was discovered by the same team using the same telescope array a series of radio telescopes ranging from the South Pole Antarctica called the South Pole telescope to the neighbor of the bicep telescope of Antarctica all the way to Chile and other telescopes throughout the planet constructing a planetary siiz telescope that allows scientists with very small wavelengths millimeter wavelengths to image the black hole and its properties now m87 is about 60 million light years away in the Virgo cluster it's a behemoth with a trillion Stars five times as many as The Milky Way galaxy and the black hole at its core is about 2 million times the mass of our sun and the black hole in the Milky Way galaxy called Sagittarius A star discussed in today's press conference is only only quote unquote about 6 million times the mass of our sun so there's almost 500 times more mass in the Galaxy called m87 black hole than in the Milky Way Galaxy's black hole which is why they probably made that Discovery first and that announcement came in 2019 as opposed to 2022 on those scales the black hole self is minimally small now the benefit of Sagittarius A star is that it's closer to us and astronomical signals often Decay as the inverse square or sometimes even higher powers of the distance from the object to the Observer here on Earth the smaller size of the Sagittarius AAR black Hall meant that light traverses it in a much shorter amount of time far far shorter than the time that it would take for a light to Traverse the black hole in m87 meaning that in just about 20 minutes you could get many images of how the Dynamics of this black hole are changing you could effectively make a movie because of the black hole's compact size you couldn't do this with m87 as cool as that was upcoming results in combination with the infrared images of Sagittarius A star from Andrea gz's group and Reinhardt gel's group make for an amazing so-called multi messenger astronomical Extravaganza we're using multiple wavelength range each providing a unique finger print a Rosetta Stone contribution if you will whatever metaphor you like to better understand the properties of gravity of space 's radical curvature at these Behemoth size skills yes come on what an amazing time to be alive as an utterly new window on the cosmos is opened thanks to stunning new technology like Adaptive Optics polarization sensitivity and very long Baseline interferometry using a planetary size telesc you can watch the whole press conference at the link in the video description below we also had conversations as an experimentalist with the leaders of this Event Horizon Project telescope now these team leaders that I've conversed with including Shep dolman and Hyo fala provide amazing insight into what it's like to actually build this technology and operate it and not least of all analyze the data from it so that we truly can understand what gravity behaves like in the most extreme circumstances in the known universe so let me know in the comments what black hole do you think the Event Horizon telescope should turn its powerful eye to next check out this playlist combining my conversations with phenomenal brilliant theorists like Delila Gates like Kon vafa and with Juan Mala about the properties of black holes and what they teach us about entropy time Dynamics as well