March 19, 2025 • 25 mins
"Supermassive Giants" explores the mind-bending world of supermassive black holes through the engaging perspective of host Felix Mercer. This conversational journey takes listeners from our own galaxy's relatively modest Sagittarius A* to the behemoth M87*, explaining how these cosmic titans shape galactic evolution and challenge our understanding of physics. Felix brings complex astrophysics to life with his characteristic blend of scientific accuracy, thoughtful metaphors, and contagious wonder. For more captivating cosmic explorations and thought-provoking science content, visit https://www.quietperiodplease.com/ – your destination for engaging podcasts that transform complex ideas into accessible adventures.
Mark as Played
Transcript
Episode Transcript
Available transcripts are automatically generated. Complete accuracy is not guaranteed.
Speaker 1 (00:00):
Hello, they're cosmic wanderers and curious minds. Felix Mercer here
welcoming you to another episode of black Holes, where we
dive into the most enigmatic phenomena in our universe without
the safety gear that common sense might recommend. Today we're
tackling titans that would make Godzilla look like a house pet,
(00:22):
super massive black holes, the colossal gravitational architects at the
hearts of galaxies. Now, before we plunge into these cosmic abysses,
I want you to imagine something with me. Picture yourself
standing at the edge of the Grand Canyon. Impressive right now.
Multiply that sense of vastness by oh, let's say a trillion,
(00:46):
and you're still nowhere near grasping the scale of what
we're discussing today. These celestial leviathans aren't just big. They're
mind bendingly reality warpingly enormous, with masses millions to billions
times that of our Sun, all compressed into regions smaller
than our solar system. And you know what's truly wild.
(01:09):
These cosmic giants are simultaneously the most dramatic and the
shyest performers in the universe. They shape entire galaxies with
their gravitational influence, yet they're completely invisible to direct observation.
Talk about stage fright, but don't worry. Like good cosmic detectives,
(01:30):
we've developed methods to catch them in the act, and
that's part of our journey today. So grab your imaginary
spacesuits and metaphorical gravity boots. We're heading toward the most
extreme environments in existence, where space and time themselves surrender
to the irresistible pull of supermassive black holes. When I
(01:53):
was a kid, I used to think black holes were
just cosmic vacuum cleaners, sucking up anything that wandered to close.
It's a common misconception, one that I find endearingly simplistic. Now,
the truth, as it often is in science, is far
more fascinating. Supermassive black holes aren't just destructive forces. They're
(02:16):
creative ones, too, playing crucial roles in how galaxies form
and evolve. They're less like vacuum cleaners and more like
cosmic conductors orchestrating the grand symphony of galactic evolution. Let's
start with the basics. At the center of nearly every
large galaxy we've studied, lurks a supermassive black hole. Our
(02:39):
own Milky Way harbors a relatively modest specimen named Sagittarius,
a star pronounced Sagittarius, a star weighing in at about
four million solar masses. That might sound impressive until you
meet the heavyweight champions, like the black hole at the
center of the galaxy M eighty, which tips the cosmic
(03:02):
scales at a staggering six point five billion solar masses.
That's billion with a B, a number so large it
makes my brain do somersaults. But how did those cosmic
monsters come to be? That's a question that still keeps
astrophysicists up at night, staring at their ceiling fans and
(03:23):
contemplating the mysteries of the universe. Unlike stellar mass black holes,
which form from the collapsed cores of massive stars, super
massive black holes present us with a cosmic chicken and
egg problem. Did galaxies form first, creating environments where those
black holes could grow, or did the black holes form
(03:45):
early in cosmic history, serving as seeds around which galaxies
could coalesce. Current evidence suggests it might be a bit
of both, with feedback loops between black hole and galaxy
growth creating a cosmic dance of mutual influence. It's like
asking whether the conductor shapes the orchestra, or if the
(04:08):
orchestra molds the conductor. In reality, they evolve together, each
responding to and shaping the other. The earliest supermassive black
holes likely formed from the collapse of massive gas clouds
in the early universe, creating seed black holes that were
already quite hefty by stellar standards. These seeds then grew
(04:31):
through two primary mechanisms, by consuming vast amounts of gas
and dust, a process called accretion, and by merging with
other black holes during galaxy collisions. Its cosmic gluttony and
cosmic matchmaking all wrapped into one fascinating evolutionary story. When
(04:51):
supermassive black holes actively feed on surrounding material, they become
some of the most luminous objects in the universe. Not
because light escapes from the black holes themselves, nothing does that,
but because the material spiraling into them gets superheated to
millions of degrees, creating what we call an accretion disc.
(05:15):
This disk shines brightly across multiple wavelengths, from radio waves
to X rays, and can outshine all the stars in
the host galaxy. Combined. We call these feeding black holes
active galactic nuclei, or agn, and they come in various
flavors depending on our viewing angle and the black hole's
(05:36):
feeding rate. Some supermassive black holes are particularly dramatic eaters,
shooting out vast jets of particles moving at nearly the
speed of light, extending far beyond their host galaxies. These
jets can stretch for hundreds of thousands of light years,
influencing the inner galactic medium on scales that defy imagination.
(06:00):
It's as if your dining habits could affect weather patterns
on the other side of the planet. The relationship between
supermassive black holes and their host galaxies is one of
the most fascinating cosmic partnerships we've discovered. There's a remarkably
tight correlation between the mass of a galaxy central bulge,
(06:22):
the concentrated spherical collection of stars at its center, and
the mass of its supermassive black hole. This relationship is
so consistent that it can't possibly be coincidental. Its evidence
of deep fundamental connections between black hole growth and galaxy evolution.
(06:42):
This connection manifests most dramatically in what astronomers call feedback
the way a feeding black hole can influence its host galaxy.
As material falls toward a supermassive black hole, it doesn't
all make it past the event horizon. Some of it
gets superheated and blown back out into the galaxy in
(07:04):
powerful winds and jets. This outflowing material can heat or
even expel the cold gas needed to form new stars,
effectively putting the brakes on star formation. Its nature's version
of self regulation. The black hole grows by feeding on gas,
but as it feeds more vigorously, it eventually blows away
(07:26):
its own food supply, temporarily halting both star formation and
its own growth. Imagine a cosmic thermostat of sorts, preventing
galaxies from becoming two star rich or black holes from
growing too massive. This feedback mechanism helps explain why we
don't see galaxies above a certain mass in our universe,
(07:49):
and why black hole growth and star formation appear to
have peaked at similar times in cosmic history. Let's zoom
in on our cosmic backyard for a moment and meet
our own supermassive companion, Sagittarius, a star sggr astar for
short lurking twenty six thousand light years away at the
(08:12):
heart of the Milky Way. This four million solar mass
black hole is practically our next door neighbor in cosmic terms,
Unlike many supermassive black holes, as GRA Star is relatively
quiet these days, it's not completely inactive. It still nibbles
on the occasional gas cloud or wayward star, but its
(08:35):
feeding rate is paltry compared to the voracious appetites of
active galactic nuclei in other galaxies. This quiscence is actually
convenient for astronomers, as it allows us to observe stars
orbiting very close to the black hole without their light
being overwhelmed by the glare of an active accretion disc.
(08:57):
One of these stars, designated S to two U, has
provided some of the most compelling evidence for sgr Astar's existence.
S two whips around the black hole in an elliptical orbit,
approaching within just one hundred twenty astronomical units, about four
times the distance from the Sun to Neptune at its
(09:19):
closest approach, and reaching speeds of up to three percent
of the speed of light. By tracking S two's orbit
over multiple decades, astronomers have not only confirmed the presence
of a concentrated mass at the galactic center, but have
also measured its properties with increasingly stunning precision. In twenty eighteen,
(09:40):
the Gravity collaboration observed S two's closest approach to sgr
Astar and detected the gravitational redshift of light from the star,
a direct consequence of Einstein's general relativity. This was followed
in twenty twenty by the detection of the Schwartzchild perc
of S two's orbit, another relativistic effect predicted by Einstein.
(10:05):
These observations don't just confirm the presence of a supermassive
black hole, they validate our understanding of how gravity works
in these extreme environments. It's like having Einstein's theories pass
a cosmic stress test with flying colors. Speaking of observational triumphs,
we can't discuss supermassive black holes without mentioning M eight
(10:29):
seven star, the central black hole of the galaxy Messire
eighty seven, which in twenty nineteen became the first black
hole ever to have its photograph taken. This image, captured
by the Event Horizon Telescope collaboration, shows not the black
hole itself, which true to its name amidst no light
(10:51):
but the glowing ring of material around it, with a
dark central shadow, where light paths either terminate at the
event horizon or or get bent away from our line
of sight. MA eight seven asterisk is a true behemoth,
with a mass six point five billion times that of
our Sun. If placed in our solar system, its event
(11:14):
horizon would engulf the orbits of all planets out to
Neptune and beyond. Despite this enormous size, capturing its image
required an Earth sized virtual telescope created by synchronizing radio
observatories across our planet. The resulting image represents one of
(11:34):
humanity's greatest scientific achievements. We manage to photograph the unseeable,
to capture the shadow of a monster that devours even
light itself. Unlike our relatively docial Sgrastarm eight seven star
is actively feeding and producing enormous jets of particles that
(11:55):
extend far beyond its host galaxy. These jets, first observed
over a century ago, emerge from the regions near the
black hole's poles and provide a cosmic laboratory for studying
particle acceleration and magnetic fields in extreme environments. The twenty
nineteen image revealed that the ring of a mission around
(12:18):
M eight seven star appears brighter on one side than
the other, exactly as predicted by models where material orbits
the black hole at close to the speed of light,
causing relativistic beaming of the emission. The fact that we
can now directly image these remote cosmic monsters represents an
(12:39):
extraordinary convergence of theory, technology, and human ingenuity. It's a
testament to how far we've come from the days when
black holes were considered mathematical curiosities rather than real astronomical objects.
But how exactly do we study objects that, by definition,
cannot be seen directly. The toolkit of modern astronomers is
(13:03):
as diverse as it is sophisticated, allowing us to probe
these invisible giants through their effects on surrounding matter in
space time itself. The most traditional approach involves studying the
orbital dynamics of objects near the black hole. Just as
we can infer the presence of an unseen planet by
(13:23):
observing the wobble it induces in its star, we can
detect black holes by tracking stars or gas clouds that
orbit them. This method has been particularly fruitful for our
own galactic center, where individual stars can be resolved and
tracked over decades. Another powerful technique involves measuring the velocities
(13:47):
of stars or gas throughout a galaxy. In regions close
to a black hole, these velocities increase dramatically, a direct
consequence of the black hole's gravitational poll By mapping these
velocity fields and modeling the mass distribution needed to produce them,
astronomers can infer not just the presence of a central
(14:09):
black hole, but also estimate its mass with remarkable precision.
For actively feeding black holes, we can study the properties
of their accretion disks and jets. The spectrum of light
emitted by these structures contains information about the black hole's mass, spin,
and feeding rate. By observing how this emission varies over time,
(14:33):
sometimes on time scales as short as minutes, astronomers can
probe regions incredibly close to the event horizon where the
most extreme physics occurs. Perhaps the most cutting edge method
involves interferometry, the technique that gave us the groundbreaking image
of M eight seven star. By combining signals from multiple
(14:57):
telescopes separated by large dedas distances, interferometers achieve resolution equivalent
to a single telescope as large as the distance between
the component observatories. This has allowed us to resolve structures
on scales comparable to the event horizons of the nearest
supermassive black holes. The Event Horizon Telescope EHT represents the
(15:23):
pinnacle of this approach, linking radio telescopes across the globe
to create a virtual Earth sized observatory. The twenty nineteen
image of M eight seven Star was just the beginning.
The EHT has since imaged sqr Astar as well, despite
the significant challenges posed by its smaller size and the
(15:46):
turbulent plasma in our galaxy that distorts the incoming radio waves.
And we're not stopping there. Future enhancements to the EHT,
including the addition of space based telescopes, will show SARP
in our view even further. Meanwhile, other facilities like the
James Webb Space Telescope are providing unprecedented views of distant
(16:10):
active galaxies, allowing us to study super massive black holes
across cosmic time. But perhaps the most revolutionary new window
into black hole physics comes from gravitational waves, ripples, and
space time produced when massive objects accelerate The Ligo and
Virgo detectors have already detected numerous mergers of stellar mass
(16:34):
black holes, and future observatories like LISA the Laser Interferometer
space antenna will be sensitive to the lower frequency gravitational
waves produced when super massive black holes merge. These observations
will provide entirely new insights into black hole populations and evolution,
(16:56):
completely independent of traditional electromagnetic astronomy. Each of these techniques
has its strengths and limitations, but collectively they form a
powerful arsenal for probing some of the most extreme environments
in the universe. It's like examining a mountain from multiple
vantage points. Each perspective reveals different aspects of the same
(17:19):
majestic structure. The study of supermassive black holes isn't just
an academic exercise. It touches on some of the most
fundamental questions in physics and cosmology. How did the first
black holes form in the early universe? How did they
grow and evolve over cosmic time, what role do they
(17:41):
play in regulating galaxy growth? And, perhaps most tantalizing of all,
what can they teach us about the nature of space,
time and gravity? At the very heart of a black
hole lies what physicists call a singularity, a point where,
according to general relativity, matter is compressed to infinite density
(18:03):
and space time curvature becomes infinite. This mathematical breakdown of
our best theory of gravity strongly suggests that we need
a quantum theory of gravity to fully understand what happens
at the centers of black holes. In this sense, black
holes represent cosmic laboratories where the two pillars of modern physics,
(18:25):
quantum mechanics and general relativity, must somehow be reconciled. This
reconciliation remains one of the greatest unsolved problems in theoretical physics.
With approaches like string theory and loop quantum gravity offering
potential pathways forward, Supermassive black holes, with their enormous masses
(18:48):
and relatively mild tidal forces at their event horizons compared
to stellar mass black holes, might someday provide observational tests
for these theories. Even without a complete theory of quantum gravity,
supermassive black holes continue to surprise us with unexpected behaviors.
For instance, we've observed enormous flares from apparently quiescent black holes,
(19:14):
including sgraios, suggesting that even dormant black holes can experience
dramatic feeding events when unlucky gas clouds or stars wander
too close. The discovery of gravitational waves has opened an
entirely new frontier in black hole research. While current detectors
(19:35):
are sensitive primarily to stellar mass black hole mergers, the
upcoming LSA mission will target the frequency range where supermassive
black hole mergers should be detectable. Thus, observations will provide
direct measurements of black hole masses and spins before, during,
and after mergers, offering unprecedented insights into how these objects go,
(20:00):
combine and grow. We're also discovering fascinating populations of intermediate
mass black holes with masses between one hundred and a
million times that of the Sun. These objects might represent
the missing link between stellar mass and supermassive black holes,
potentially revealing how the latter grew so quickly in the
(20:22):
early universe. Some may hide in the centers of dwarf
galaxies or even orbit as satellites to larger black holes
in galaxy centers. The pace of discovery in this field
is accelerating, driven by new observational capabilities and theoretical insights.
The next decade promises to be particularly exciting, with facilities
(20:45):
like the extremely large telescope, the Square Kilometer Array, and
LSA coming online. Each will provide new perspectives on these
cosmic enigmas, pushing the boundaries of our understanding ever from
But as we peel back the layers of mystery surrounding
supermassive black holes, we inevitably encounter new questions, new puzzles,
(21:10):
and new conundrums. That's the beauty of science. Every answer
leads to deeper questions, keeping us humble and curious in
the face of cosmic grandeur. I think that's what draws
me to black holes more than anything else. They remind
us of how much we still don't know. These objects,
(21:32):
predicted by the mathematics of general relativity long before we
had any hope of detecting them, represent triumphs of human
intellect and imagination. Yet they also embody the limitations of
our current understanding, challenging us to push beyond established paradigms
and comfortable assumptions. In a universe full of wonders, supermassive
(21:57):
black holes stand out as particularly enigmatic characters. Brooding giants,
that shape cosmic destinies while remaining shrouded in mystery. Their
nature's ultimate paradox. Objects so massive that nothing, not even light,
can escape their gravitational clutches, yet so influential that their
(22:20):
effects propagate across billions of light years. As we continue
to study these cosmic leviathans, we're not just learning about
exotic astrophysical objects. We're probing the fundamental nature of reality itself.
The extreme physics near black hole event horizons tests our
most cherished theories. While the role of black holes in
(22:43):
galaxy evolution illuminates the complex interplay of forces that shaped
our cosmic neighborhood, The story of supermassive black holes is
in many ways our own story. The heavy elements that
make up our bodies were forged in stellar furnaces and
scattered by supernovae, the very processes that create stellar mass
(23:06):
black holes. Meanwhile, our galaxy structure, including the spiral arms
where our Solar System resides, has been influenced by the
gravitational presence of Sagittarius, a star at the Milky Way's heart.
We are, in a very real sense, children of the
stars and subjects of the central black hole this cosmic
(23:28):
perspective doesn't diminish our significance, it enhances it. We are
the universe becoming aware of itself. The means by which
these extraordinary objects can be known and understood. Our curiosity,
our ingenuity, our stubborn refusal to accept ignorance, These very
(23:48):
human qualities have allowed us to discover and comprehend phenomena
that exist on scales vastly beyond our everyday experience. So
the next time you look up at the night sky,
remember that beyond those twinkling stars, past the beautiful spiral
arms of our galaxy, sits a supermassive black hole, a
(24:11):
cosmic colossus that, despite its intimidating nature, has played a
role in creating the conditions that allowed us to evolve
and thrive. There's poetry in that connection, a profound link
between the most extreme objects in the universe and the
consciousness that seeks to understand them. And that, my friends,
(24:33):
is the true wonder of supermassive black holes, not just
what they are, but what they mean for our place
in the cosmic story. They remind us that we inhabit
a universe more strange, more beautiful, and more interconnected than
our ancestors could have possibly imagined a universe where invisible
(24:55):
giants shape the destiny of galaxies, and where curious primates
on a small blue planet can somehow comprehend it all.
As we continue to probe these cosmic enigmas will undoubtedly
uncover new surprises, new challenges to our understanding, and new
opportunities for wonder. The journey of discovery never truly ends.
(25:19):
Each answer simply illuminates the path to deeper questions, and
that perhaps is the greatest gift that supermassive black holes
offer us, not final answers, but eternal curiosity. Thanks for listening, everyone,
Please subscribe for more cosmic adventures where we explore the
(25:40):
most fascinating aspects of our universe. This has been black Holes,
brought to you by Quiet Please Podcast Networks. For more
content like this, please go to Quiet Please dot Ai
Hello, they're cosmic wanderers and curious minds. Felix Mercer here
welcoming you to another episode of black Holes, where we
dive into the most enigmatic phenomena in our universe without
the safety gear that common sense might recommend. Today we're
tackling titans that would make Godzilla look like a house pet,
(00:22):
super massive black holes, the colossal gravitational architects at the
hearts of galaxies. Now, before we plunge into these cosmic abysses,
I want you to imagine something with me. Picture yourself
standing at the edge of the Grand Canyon. Impressive right now.
Multiply that sense of vastness by oh, let's say a trillion,
(00:46):
and you're still nowhere near grasping the scale of what
we're discussing today. These celestial leviathans aren't just big. They're
mind bendingly reality warpingly enormous, with masses millions to billions
times that of our Sun, all compressed into regions smaller
than our solar system. And you know what's truly wild.
(01:09):
These cosmic giants are simultaneously the most dramatic and the
shyest performers in the universe. They shape entire galaxies with
their gravitational influence, yet they're completely invisible to direct observation.
Talk about stage fright, but don't worry. Like good cosmic detectives,
(01:30):
we've developed methods to catch them in the act, and
that's part of our journey today. So grab your imaginary
spacesuits and metaphorical gravity boots. We're heading toward the most
extreme environments in existence, where space and time themselves surrender
to the irresistible pull of supermassive black holes. When I
(01:53):
was a kid, I used to think black holes were
just cosmic vacuum cleaners, sucking up anything that wandered to close.
It's a common misconception, one that I find endearingly simplistic. Now,
the truth, as it often is in science, is far
more fascinating. Supermassive black holes aren't just destructive forces. They're
(02:16):
creative ones, too, playing crucial roles in how galaxies form
and evolve. They're less like vacuum cleaners and more like
cosmic conductors orchestrating the grand symphony of galactic evolution. Let's
start with the basics. At the center of nearly every
large galaxy we've studied, lurks a supermassive black hole. Our
(02:39):
own Milky Way harbors a relatively modest specimen named Sagittarius,
a star pronounced Sagittarius, a star weighing in at about
four million solar masses. That might sound impressive until you
meet the heavyweight champions, like the black hole at the
center of the galaxy M eighty, which tips the cosmic
(03:02):
scales at a staggering six point five billion solar masses.
That's billion with a B, a number so large it
makes my brain do somersaults. But how did those cosmic
monsters come to be? That's a question that still keeps
astrophysicists up at night, staring at their ceiling fans and
(03:23):
contemplating the mysteries of the universe. Unlike stellar mass black holes,
which form from the collapsed cores of massive stars, super
massive black holes present us with a cosmic chicken and
egg problem. Did galaxies form first, creating environments where those
black holes could grow, or did the black holes form
(03:45):
early in cosmic history, serving as seeds around which galaxies
could coalesce. Current evidence suggests it might be a bit
of both, with feedback loops between black hole and galaxy
growth creating a cosmic dance of mutual influence. It's like
asking whether the conductor shapes the orchestra, or if the
(04:08):
orchestra molds the conductor. In reality, they evolve together, each
responding to and shaping the other. The earliest supermassive black
holes likely formed from the collapse of massive gas clouds
in the early universe, creating seed black holes that were
already quite hefty by stellar standards. These seeds then grew
(04:31):
through two primary mechanisms, by consuming vast amounts of gas
and dust, a process called accretion, and by merging with
other black holes during galaxy collisions. Its cosmic gluttony and
cosmic matchmaking all wrapped into one fascinating evolutionary story. When
(04:51):
supermassive black holes actively feed on surrounding material, they become
some of the most luminous objects in the universe. Not
because light escapes from the black holes themselves, nothing does that,
but because the material spiraling into them gets superheated to
millions of degrees, creating what we call an accretion disc.
(05:15):
This disk shines brightly across multiple wavelengths, from radio waves
to X rays, and can outshine all the stars in
the host galaxy. Combined. We call these feeding black holes
active galactic nuclei, or agn, and they come in various
flavors depending on our viewing angle and the black hole's
(05:36):
feeding rate. Some supermassive black holes are particularly dramatic eaters,
shooting out vast jets of particles moving at nearly the
speed of light, extending far beyond their host galaxies. These
jets can stretch for hundreds of thousands of light years,
influencing the inner galactic medium on scales that defy imagination.
(06:00):
It's as if your dining habits could affect weather patterns
on the other side of the planet. The relationship between
supermassive black holes and their host galaxies is one of
the most fascinating cosmic partnerships we've discovered. There's a remarkably
tight correlation between the mass of a galaxy central bulge,
(06:22):
the concentrated spherical collection of stars at its center, and
the mass of its supermassive black hole. This relationship is
so consistent that it can't possibly be coincidental. Its evidence
of deep fundamental connections between black hole growth and galaxy evolution.
(06:42):
This connection manifests most dramatically in what astronomers call feedback
the way a feeding black hole can influence its host galaxy.
As material falls toward a supermassive black hole, it doesn't
all make it past the event horizon. Some of it
gets superheated and blown back out into the galaxy in
(07:04):
powerful winds and jets. This outflowing material can heat or
even expel the cold gas needed to form new stars,
effectively putting the brakes on star formation. Its nature's version
of self regulation. The black hole grows by feeding on gas,
but as it feeds more vigorously, it eventually blows away
(07:26):
its own food supply, temporarily halting both star formation and
its own growth. Imagine a cosmic thermostat of sorts, preventing
galaxies from becoming two star rich or black holes from
growing too massive. This feedback mechanism helps explain why we
don't see galaxies above a certain mass in our universe,
(07:49):
and why black hole growth and star formation appear to
have peaked at similar times in cosmic history. Let's zoom
in on our cosmic backyard for a moment and meet
our own supermassive companion, Sagittarius, a star sggr astar for
short lurking twenty six thousand light years away at the
(08:12):
heart of the Milky Way. This four million solar mass
black hole is practically our next door neighbor in cosmic terms,
Unlike many supermassive black holes, as GRA Star is relatively
quiet these days, it's not completely inactive. It still nibbles
on the occasional gas cloud or wayward star, but its
(08:35):
feeding rate is paltry compared to the voracious appetites of
active galactic nuclei in other galaxies. This quiscence is actually
convenient for astronomers, as it allows us to observe stars
orbiting very close to the black hole without their light
being overwhelmed by the glare of an active accretion disc.
(08:57):
One of these stars, designated S to two U, has
provided some of the most compelling evidence for sgr Astar's existence.
S two whips around the black hole in an elliptical orbit,
approaching within just one hundred twenty astronomical units, about four
times the distance from the Sun to Neptune at its
(09:19):
closest approach, and reaching speeds of up to three percent
of the speed of light. By tracking S two's orbit
over multiple decades, astronomers have not only confirmed the presence
of a concentrated mass at the galactic center, but have
also measured its properties with increasingly stunning precision. In twenty eighteen,
(09:40):
the Gravity collaboration observed S two's closest approach to sgr
Astar and detected the gravitational redshift of light from the star,
a direct consequence of Einstein's general relativity. This was followed
in twenty twenty by the detection of the Schwartzchild perc
of S two's orbit, another relativistic effect predicted by Einstein.
(10:05):
These observations don't just confirm the presence of a supermassive
black hole, they validate our understanding of how gravity works
in these extreme environments. It's like having Einstein's theories pass
a cosmic stress test with flying colors. Speaking of observational triumphs,
we can't discuss supermassive black holes without mentioning M eight
(10:29):
seven star, the central black hole of the galaxy Messire
eighty seven, which in twenty nineteen became the first black
hole ever to have its photograph taken. This image, captured
by the Event Horizon Telescope collaboration, shows not the black
hole itself, which true to its name amidst no light
(10:51):
but the glowing ring of material around it, with a
dark central shadow, where light paths either terminate at the
event horizon or or get bent away from our line
of sight. MA eight seven asterisk is a true behemoth,
with a mass six point five billion times that of
our Sun. If placed in our solar system, its event
(11:14):
horizon would engulf the orbits of all planets out to
Neptune and beyond. Despite this enormous size, capturing its image
required an Earth sized virtual telescope created by synchronizing radio
observatories across our planet. The resulting image represents one of
(11:34):
humanity's greatest scientific achievements. We manage to photograph the unseeable,
to capture the shadow of a monster that devours even
light itself. Unlike our relatively docial Sgrastarm eight seven star
is actively feeding and producing enormous jets of particles that
(11:55):
extend far beyond its host galaxy. These jets, first observed
over a century ago, emerge from the regions near the
black hole's poles and provide a cosmic laboratory for studying
particle acceleration and magnetic fields in extreme environments. The twenty
nineteen image revealed that the ring of a mission around
(12:18):
M eight seven star appears brighter on one side than
the other, exactly as predicted by models where material orbits
the black hole at close to the speed of light,
causing relativistic beaming of the emission. The fact that we
can now directly image these remote cosmic monsters represents an
(12:39):
extraordinary convergence of theory, technology, and human ingenuity. It's a
testament to how far we've come from the days when
black holes were considered mathematical curiosities rather than real astronomical objects.
But how exactly do we study objects that, by definition,
cannot be seen directly. The toolkit of modern astronomers is
(13:03):
as diverse as it is sophisticated, allowing us to probe
these invisible giants through their effects on surrounding matter in
space time itself. The most traditional approach involves studying the
orbital dynamics of objects near the black hole. Just as
we can infer the presence of an unseen planet by
(13:23):
observing the wobble it induces in its star, we can
detect black holes by tracking stars or gas clouds that
orbit them. This method has been particularly fruitful for our
own galactic center, where individual stars can be resolved and
tracked over decades. Another powerful technique involves measuring the velocities
(13:47):
of stars or gas throughout a galaxy. In regions close
to a black hole, these velocities increase dramatically, a direct
consequence of the black hole's gravitational poll By mapping these
velocity fields and modeling the mass distribution needed to produce them,
astronomers can infer not just the presence of a central
(14:09):
black hole, but also estimate its mass with remarkable precision.
For actively feeding black holes, we can study the properties
of their accretion disks and jets. The spectrum of light
emitted by these structures contains information about the black hole's mass, spin,
and feeding rate. By observing how this emission varies over time,
(14:33):
sometimes on time scales as short as minutes, astronomers can
probe regions incredibly close to the event horizon where the
most extreme physics occurs. Perhaps the most cutting edge method
involves interferometry, the technique that gave us the groundbreaking image
of M eight seven star. By combining signals from multiple
(14:57):
telescopes separated by large dedas distances, interferometers achieve resolution equivalent
to a single telescope as large as the distance between
the component observatories. This has allowed us to resolve structures
on scales comparable to the event horizons of the nearest
supermassive black holes. The Event Horizon Telescope EHT represents the
(15:23):
pinnacle of this approach, linking radio telescopes across the globe
to create a virtual Earth sized observatory. The twenty nineteen
image of M eight seven Star was just the beginning.
The EHT has since imaged sqr Astar as well, despite
the significant challenges posed by its smaller size and the
(15:46):
turbulent plasma in our galaxy that distorts the incoming radio waves.
And we're not stopping there. Future enhancements to the EHT,
including the addition of space based telescopes, will show SARP
in our view even further. Meanwhile, other facilities like the
James Webb Space Telescope are providing unprecedented views of distant
(16:10):
active galaxies, allowing us to study super massive black holes
across cosmic time. But perhaps the most revolutionary new window
into black hole physics comes from gravitational waves, ripples, and
space time produced when massive objects accelerate The Ligo and
Virgo detectors have already detected numerous mergers of stellar mass
(16:34):
black holes, and future observatories like LISA the Laser Interferometer
space antenna will be sensitive to the lower frequency gravitational
waves produced when super massive black holes merge. These observations
will provide entirely new insights into black hole populations and evolution,
(16:56):
completely independent of traditional electromagnetic astronomy. Each of these techniques
has its strengths and limitations, but collectively they form a
powerful arsenal for probing some of the most extreme environments
in the universe. It's like examining a mountain from multiple
vantage points. Each perspective reveals different aspects of the same
(17:19):
majestic structure. The study of supermassive black holes isn't just
an academic exercise. It touches on some of the most
fundamental questions in physics and cosmology. How did the first
black holes form in the early universe? How did they
grow and evolve over cosmic time, what role do they
(17:41):
play in regulating galaxy growth? And, perhaps most tantalizing of all,
what can they teach us about the nature of space,
time and gravity? At the very heart of a black
hole lies what physicists call a singularity, a point where,
according to general relativity, matter is compressed to infinite density
(18:03):
and space time curvature becomes infinite. This mathematical breakdown of
our best theory of gravity strongly suggests that we need
a quantum theory of gravity to fully understand what happens
at the centers of black holes. In this sense, black
holes represent cosmic laboratories where the two pillars of modern physics,
(18:25):
quantum mechanics and general relativity, must somehow be reconciled. This
reconciliation remains one of the greatest unsolved problems in theoretical physics.
With approaches like string theory and loop quantum gravity offering
potential pathways forward, Supermassive black holes, with their enormous masses
(18:48):
and relatively mild tidal forces at their event horizons compared
to stellar mass black holes, might someday provide observational tests
for these theories. Even without a complete theory of quantum gravity,
supermassive black holes continue to surprise us with unexpected behaviors.
For instance, we've observed enormous flares from apparently quiescent black holes,
(19:14):
including sgraios, suggesting that even dormant black holes can experience
dramatic feeding events when unlucky gas clouds or stars wander
too close. The discovery of gravitational waves has opened an
entirely new frontier in black hole research. While current detectors
(19:35):
are sensitive primarily to stellar mass black hole mergers, the
upcoming LSA mission will target the frequency range where supermassive
black hole mergers should be detectable. Thus, observations will provide
direct measurements of black hole masses and spins before, during,
and after mergers, offering unprecedented insights into how these objects go,
(20:00):
combine and grow. We're also discovering fascinating populations of intermediate
mass black holes with masses between one hundred and a
million times that of the Sun. These objects might represent
the missing link between stellar mass and supermassive black holes,
potentially revealing how the latter grew so quickly in the
(20:22):
early universe. Some may hide in the centers of dwarf
galaxies or even orbit as satellites to larger black holes
in galaxy centers. The pace of discovery in this field
is accelerating, driven by new observational capabilities and theoretical insights.
The next decade promises to be particularly exciting, with facilities
(20:45):
like the extremely large telescope, the Square Kilometer Array, and
LSA coming online. Each will provide new perspectives on these
cosmic enigmas, pushing the boundaries of our understanding ever from
But as we peel back the layers of mystery surrounding
supermassive black holes, we inevitably encounter new questions, new puzzles,
(21:10):
and new conundrums. That's the beauty of science. Every answer
leads to deeper questions, keeping us humble and curious in
the face of cosmic grandeur. I think that's what draws
me to black holes more than anything else. They remind
us of how much we still don't know. These objects,
(21:32):
predicted by the mathematics of general relativity long before we
had any hope of detecting them, represent triumphs of human
intellect and imagination. Yet they also embody the limitations of
our current understanding, challenging us to push beyond established paradigms
and comfortable assumptions. In a universe full of wonders, supermassive
(21:57):
black holes stand out as particularly enigmatic characters. Brooding giants,
that shape cosmic destinies while remaining shrouded in mystery. Their
nature's ultimate paradox. Objects so massive that nothing, not even light,
can escape their gravitational clutches, yet so influential that their
(22:20):
effects propagate across billions of light years. As we continue
to study these cosmic leviathans, we're not just learning about
exotic astrophysical objects. We're probing the fundamental nature of reality itself.
The extreme physics near black hole event horizons tests our
most cherished theories. While the role of black holes in
(22:43):
galaxy evolution illuminates the complex interplay of forces that shaped
our cosmic neighborhood, The story of supermassive black holes is
in many ways our own story. The heavy elements that
make up our bodies were forged in stellar furnaces and
scattered by supernovae, the very processes that create stellar mass
(23:06):
black holes. Meanwhile, our galaxy structure, including the spiral arms
where our Solar System resides, has been influenced by the
gravitational presence of Sagittarius, a star at the Milky Way's heart.
We are, in a very real sense, children of the
stars and subjects of the central black hole this cosmic
(23:28):
perspective doesn't diminish our significance, it enhances it. We are
the universe becoming aware of itself. The means by which
these extraordinary objects can be known and understood. Our curiosity,
our ingenuity, our stubborn refusal to accept ignorance, These very
(23:48):
human qualities have allowed us to discover and comprehend phenomena
that exist on scales vastly beyond our everyday experience. So
the next time you look up at the night sky,
remember that beyond those twinkling stars, past the beautiful spiral
arms of our galaxy, sits a supermassive black hole, a
(24:11):
cosmic colossus that, despite its intimidating nature, has played a
role in creating the conditions that allowed us to evolve
and thrive. There's poetry in that connection, a profound link
between the most extreme objects in the universe and the
consciousness that seeks to understand them. And that, my friends,
(24:33):
is the true wonder of supermassive black holes, not just
what they are, but what they mean for our place
in the cosmic story. They remind us that we inhabit
a universe more strange, more beautiful, and more interconnected than
our ancestors could have possibly imagined a universe where invisible
(24:55):
giants shape the destiny of galaxies, and where curious primates
on a small blue planet can somehow comprehend it all.
As we continue to probe these cosmic enigmas will undoubtedly
uncover new surprises, new challenges to our understanding, and new
opportunities for wonder. The journey of discovery never truly ends.
(25:19):
Each answer simply illuminates the path to deeper questions, and
that perhaps is the greatest gift that supermassive black holes
offer us, not final answers, but eternal curiosity. Thanks for listening, everyone,
Please subscribe for more cosmic adventures where we explore the
(25:40):
most fascinating aspects of our universe. This has been black Holes,
brought to you by Quiet Please Podcast Networks. For more
content like this, please go to Quiet Please dot Ai
Popular Podcasts
Stuff You Should Know
If you've ever wanted to know about champagne, satanism, the Stonewall Uprising, chaos theory, LSD, El Nino, true crime and Rosa Parks, then look no further. Josh and Chuck have you covered.
Dateline NBC
Current and classic episodes, featuring compelling true-crime mysteries, powerful documentaries and in-depth investigations. Follow now to get the latest episodes of Dateline NBC completely free, or subscribe to Dateline Premium for ad-free listening and exclusive bonus content: DatelinePremium.com
New Heights with Jason & Travis Kelce
Football’s funniest family duo — Jason Kelce of the Philadelphia Eagles and Travis Kelce of the Kansas City Chiefs — team up to provide next-level access to life in the league as it unfolds. The two brothers and Super Bowl champions drop weekly insights about the weekly slate of games and share their INSIDE perspectives on trending NFL news and sports headlines. They also endlessly rag on each other as brothers do, chat the latest in pop culture and welcome some very popular and well-known friends to chat with them. Check out new episodes every Wednesday. Follow New Heights on the Wondery App, YouTube or wherever you get your podcasts. You can listen to new episodes early and ad-free, and get exclusive content on Wondery+. Join Wondery+ in the Wondery App, Apple Podcasts or Spotify. And join our new membership for a unique fan experience by going to the New Heights YouTube channel now!