Blackholes - what exactly are they?
No doubt you've heard about blackholes, perhaps in your astronomy class or from some friends. Maybe you've even seen images and videos about them on social media. But do you really know what they are besides some dark "holes" in space that's already pitch black.......
Read on to find out!
What is a blackhole?
First off, visuals are the key to a deeper understanding of any concept - especially one as wild as a blackhole! So go on and have a look at this blackhole, photographed by NASA in 2014:
It really does look like a "black hole" doesn't it? Applause to the geniuses that thought of the name!
Take a brief moment to visualize such a phantom structure concealed amongst the stars that casually twinkle above your head every night. A bit disturbing right? Well, it's nowhere near the real picture: more than trillions of blackholes could exist within the universe right at this very moment!
Despite their rather ominous countenance, blackholes have spurred endless intrigue among the scientific community and general public for generations. Their very essence and behavior are still largely unexplained, but the incredulously fascinating information that is known, (thanks to rigorous research and experimentation) will now be shared with you!
Before we begin our blackhole breakdown, a mere warning can't be harmful: blackholes are a tricky concept (to say the least) and require a thorough understanding for both intrigue and appreciation. Keep your mind open and brace yourself for some crazy-sounding facts!
Alright, time to dig into all the fascinating aspects of these beautiful beasts.
Contextually, a blackhole can be defined as an ultra dense region of space, where the mass is so insanely large and compact that gravity exerted by the blackhole consumes anything that ventures too near. Imagine 20 million Suns fit into an area less than half the size of our solar system (around 70 billion miles in diameter). That's a supermassive blackhole for you, which can even exceed billions of Suns in mass at the largest ranges.
Now all mass has gravity. The larger the mass, the more gravitational strength it possesses. So, once again BILLIONS of our suns form supermassive blackholes. The gravity there is inescapable, literally. Not even light, which travels at 186,000 miles per second (commonly known as light speed) can flee from the suction of a blackhole.
This leads us to a discussion of perhaps the most common yet intriguing question about blackholes. Why are they black?
The answer is relatively simple: nothing escapes blackholes, not even light. We all know light produces the spectrum of colors that enables us to see. The stars that we observe in the night sky? That's just their light reaching our eyes. What about the moon? A reflection of the sun's light hitting the moon's surface and bouncing off. To sum up, what we see is the product of light. When light is absent, we see this absence in the form of darkness.
So when electromagnetic waves (aka light) are casually traveling at the fastest known speed in the cosmos and encounter a blackhole en route......bad news! Not even light speed is quick enough to pass through. All passing light is sucked inside, producing an absence of light in the region of the blackhole, which is basically how blackholes earned their name. They are pitch black, which in a looming black cosmos, appear invisible to the human eye without high-tech observational equipment.
Here's an accurate illustration of what a blackhole could resemble, if we could get close enough to see:
The red disk swirling around the blackhole is orbiting matter, known as an accretion disk. It is comprised mostly of dust and gas particles of various elements, such as carbon and hydrogen. All passing and nearby matter ends up sucked into orbit around the blackhole much like the planets orbit the Sun in our solar system. However, with blackholes, there's a catch. Matter doesn't simply stay in constant orbit, but is pulled closer and closer towards the center. This happens through the following process:
The plethora of orbiting matter interacts with itself, causing friction, and therefore, heat loss.
To demonstrate, bring the palms of your hands together and slide them against each other. You should feel warmth as heat is being released from this interaction.
The same concept applies for colliding particles within the accretion disk. The loss of energy decreases the matter's angular momentum, causing it to slow down. Which is not a good thing for the matter, because constant speed keeps it in orbit. As enough angular momentum is lost, the matter is pulled closer and closer to the blackhole at accelerating speeds until..........it falls right in.
This is where we need to talk about the event horizon. Fancy phrase right? To understand where exactly that sucked in matter goes, we must familiarize ourselves with the event horizon and its functions.
Think of two magnets. One is stationary - let's say taped to a table. The other one is in your hand. If you bring the one in your hand close enough to the taped magnet, the former will automatically be pulled in towards the latter.
Now forget magnetism and think gravity, as it works quite similarly with blackholes. Up to a certain area, matter near a blackhole will not get sucked inside, orbiting within the accretion disk. However, once the matter reaches a certain boundary between "go ahead and orbit me" and "I WILL EAT YOU RIGHT NOW", the blackhole does just that - consumes the matter (metaphorically speaking). This boundary is called the event horizon by astrophysicists, and commonly nicknamed the "point of no return."
Both names are deadly accurate. That's because it is impossible to observe any event taking place within the blackhole (since light can't escape) and that once matter enters, there's no way back out. It is eternally wiped out of existence. How? The answer lies in the understanding of a singularity.
A singularity is found at the center of a black hole. Now this is where things get weirdly complex because we're bringing in infinity. The density of a singularity is infinitely small and upon entering the event horizon, all matter is compressed down into this infinitely tiny point. As you can likely imagine, infinitely small is pretty dang small! At such a density, all conceptions of space and time are lost, meaning all entering matter itself is lost.
Even when blackholes evaporate (discussed later), no remnants of preexisting matter will ever be released. Therefore, anything that goes in, is universally vanished forever...
Now that we've discussed the singularity, even horizon and accretion disk, there is one more vital component of a black hole left to cover: quasars.
These are the brightest objects in the cosmos, forming only at the sites of supermassive blackholes, which are found at the centers of galaxies. As we've learned, the majority of orbiting matter eventually falls into the blackhole, but not all matter meets this daunting fate. Some particles are accelerated away from the blackhole's center due to the energy produced by matter being absorbed into the event horizon. These energy outbursts form particle jets, known as quasars, that stream out of the black hole's center like the intensely energetic blue jets pictured here:
Being the brightest galactic light sources, quasars signal the presence of a blackhole when observed with specialized telescopes. Think of quasars as the lights projected from a football stadium many miles away signaling an ongoing game - you can't see the stadium but you know that it's the source of the giant beams just like we know quasars signify the presence of unseen blackholes.
Additionally, decades of observational studies yielded the knowledge that quasars are the birthplaces of galaxies. Their hurling particle jets eventually form into galactic matter, such as stars, planets, and nebulas. It is not surprising then, that supermassive black holes exist at the center of nearly every galaxy, including our own!
How do Blackholes Form?
Creating a monstrous, all-consuming blackhole has got to encompass quite an effort, right? The answer is, an unfathomable amount of effort really does go into producing these cosmic beasts. And this cosmic effort comes from collapsing stars.
The adjective “collapsing” may be a bit misguiding here. No, the stars don’t topple over from their usual positions and fall downward into some unknown abyss. Physics is a bit more complicated than that.
The process of stellar collapse actually begins with the death of a star. First off, we must familiarize ourselves with the interrelationship of internal pressure and gravity within stars. In order to prevent gravitational collapse, stars undergo nuclear fusion, producing sufficient energy to create a balance between the two forces. Basically, a star generates fuel to maintain stability, allowing it to exist. However, that fuel supply is not infinite, meaning that at a certain point in its life, the star's engine will stop, leaving gravity as the sole force acting on the star. Remember how massive objects possess greater gravity? Now add the fact that gravity's counterforce has suddenly dissipated. Well, you're left with a whole LOT of gravity. So much gravity that a large star will collapse upon itself, conceiving an infinitely dense black hole within the time span of a second. Supernovae, which are immensely bright and energetic stellar explosions, often precede the gravitational crunches of stars into blackholes.
Once the star's entire mass is compacted into the singularity of a blackhole, growing season begins! The blackhole's intense gravitational field pulls in any surrounding matter, including nearby stars and even other, smaller blackholes. In order for rapid growth to occur, the blackhole must be ingesting matter at a high rate. Several factors limit blackhole growth, including its initial size as well as the accretion disk, which may radiate gas particles outward due to the friction of colliding matter. However, the extreme gravity of most blackholes allow for the rapid consumption of surrounding gases, causing the cosmic powerhouses to grow. Mergers are an even more profound growing mechanism - two massive blackholes collide, producing a single supermassive blackhole.
The mathematics behind blackhole growth is relatively straightforward. If you're familiar with the Law of Conservation of Matter and the First Law of Thermodynamics, then you're aware that both matter and energy can't be created nor destroyed, but are rather conserved, even throughout transformations.
These two principles similarly apply to blackhole growth. All the matter that enters the event horizon contributes its mass and energy to the blackhole. Some energy is often lost through friction and radiation, but overall, blackholes gain the majority of the energy and the entirety of the mass of entering matter. In turn, this additional mass causes the black hole and its event horizon to expand proportionately. For example, ingesting a giant star that doubles a blackhole's mass will simultaneously double the radius of the event horizon. So, generally speaking, ingesting a whole bunch of massive and energetic cosmic content creates larger and more powerful blackholes.
Types of Blackholes
Think of blackholes as a population of strange space creatures. Some are humungous, and some are miniscule. Some weigh more than a billion suns while others may weigh nearly as little as the mass of a single particle! Quite a diverse population right? Once again, astrophysics is no ordinary mechanism, so things are bound to exist and behave in strange manners. Luckily, astrophysicists have developed a convenient method of categorizing blackholes, largely based on their mass. The four categories of blackholes, as well as their key features, are charted below:
As you can see, the mass and size of blackholes both vary an insane amount. Their occurrence rate within our own galaxy, the Milky Way, is also drastically different for each blackhole type. Now you probably have many questions about this chart, so why don't we go over the four types of blackholes and their unique characteristics?
Stellar Blackholes
Let's begin with stellar blackholes. Technically, they are the smallest class of observable blackholes (although quantum blackholes are MUCH smaller but we'll cover them in a bit). Stellar blackholes are also the most common, constituting the vast majority of the blackhole population, based on current astrophysical analyses. The reasoning behind the name of this category of blackholes is very straightforward: they form from the gravitational collapse of stars, as we discussed earlier. However, our sun would not be able to yield such a blackhole (or any blackhole for that matter) because it is not massive enough to ignite rapid gravitational collapse. Generally, stars with with masses of at least three times the mass of our Sun are the minimum candidates for blackhole production. Although quite massive, stellar blackholes, like all blackholes cover much smaller sizes, ranging from only 12-400 miles across. The midrange - around 200 miles - is less than the size of a common hurricane!
But how can blackholes with the mass of many suns have such a small diameter? There is a simple explanation for this phenomenon. Blackholes are blackholes because of their extreme density. In a sense, they would have never formed into their ominous selves without a giant and rapid fluctuation in the star's density. The ideal atmosphere for blackhole spawns happens when the star's fuel tank runs out leaving gravity alone to conquer. The force of this exposed, suddenly-starving gravitational field, which now works at its fullest potential, becomes so powerful that it instantaneously squeezes all the star's matter VERY tightly together. A huge amount of matter in a tiny amount of space means tremendous density......and boom! A blackhole is born.
Calculate a Blackhole's Density!
To see how density causes the very massive to be present in such a small space, let's take the densities of a stellar blackhole and our sun and then compare the two. Let's say the mass of the stellar blackhole is 50 solar masses and its diameter is 200 miles. The formula for density is Density = mass/volume. The volume of a blackhole (which is essentially a sphere - more on this later) can be found using the formula for volume of a sphere: 4/3 x πr³ which gives a volume of nearly 4,190,000 miles cubed. The density of this blackhole will simplify to about 1/83,800 M☉/miles³. Meanwhile the sun with a mass of 1 M☉ and a diameter of 865,000 miles holds a density of 1/338,102,469,632,763,000 M☉/miles³ which is an astoundingly small number! Therefore, we can mathematically prove that although smaller, yet more massive, stellar blackholes are significantly denser than the much larger yet less massive sun.
Intermediate Blackholes
Now let's talk about intermediate blackholes. Until recently, scientists weren't even sure blackholes of these sizes existed in our cosmos because most blackholes fell into the very small or very large ranges. The possibility of a middle range was left a mystery for decades. However, in May of 2019, scientists at the Laser Interferometer Gravitational-Wave Observatory (LIGO) detected the presence of an intermediate blackhole through gravitational waves emitted from two blackholes merging. The discovery was revolutionary, as a whole new "species" of blackholes could now be added to the blackhole population.
Meanwhile, scientists had - and still have - a staggering amount of research to do to understand these novel beasts. Some theories proposed that certain intermediate blackholes could have formed as early as within the first few seconds of our universe's birth - when everything was unimaginably dense. Over billions of years, the blackholes may have grown into their present intermediate sizes. Another leading theory is that collisions of several massive stars in young clusters may generate an intermediate mass black hole. This is because the density of multiple stars smashing into each other is even greater than that of a single star collapsing, which means a more massive blackhole forms.
Supermassive Blackholes
The Mother Lode all cosmic wonders, the mightiest conqueror of spacetime, and the colossus of its kind...meet the supermassive blackhole!
We've already briefly mentioned a few facts about these types of blackholes here and there, but now it's time to bring in some more intrigue. First off, supermassive blackholes are among the most massive space entities out there. A hundred billion suns does sound pretty heavy right?
The formation of these titans is heavily debated in the astrophysics community. There are various primordial theories supporting supermassive blackhole formation at the earliest and densest stages of our universe, followed by growth to humungous proportions over billions of years. Another perspective is that many stellar blackholes within a star cluster may combine to form supermassive blackholes. At the current pace of astrophysical research and development, we may discover a definite formation for supermassive blackholes quite soon!
The occurrence rate of supermassive blackholes is largely predictable: one at the center of nearly every galaxy. Our own Milky Way's supermassive blackhole is called Sagittarius A* and holds a mass of about 4,000,000 suns. To compare, the largest known supermassive blackhole, TON618, weighs nearly 66,000,000,000 suns. That's 66 billion solar masses! And TON618 will likely gain even more mass as it consumes ill-fated matter that wanders too near....
Quantum Blackholes: Sci-Fi or Reality?
Potentially the most revolutionary concept to ever be explored by mankind, these tiny, currently theoretical blackholes spur intense debate.
Their existence was first proposed by physics legend Steven Hawking in 1976, who attempted to unify quantum mechanics (study of particle behavior at the smallest scales) with Einstein's theory of general relativity (describes behavior of gravity). Basically, the two are polar opposites in physics studies since gravity doesn’t apply to tiny scales while particle interactions are irrelevant on giant scales. Despite the fact that a unified theory of quantum gravity remains unproven to this day, a multitude of quantum blackhole theories - the potential key to quantum gravity - have been formulated over decades of theoretical examination, and heck, are they mind-blowing!
One of the leading theories defines the inflation period (time of instantaneous universal expansion) following the Big Bang as the catalyst of quantum blackholes. The intense fluctuations in density in this minuscule time span may have created many ultra dense regions at subatomic scales. Whether the resulting blackholes could’ve lasted through our universal expansion remains a mystery. One side of theoretical physics argues that any blackholes of such size would have immediately evaporated as the universal density decreased following inflation. Another side holds a drastically different perspective, believing quantum blackholes are consolidated within hidden extra dimensions that are too tiny for us to detect in our usual 3-dimensional (plus a time dimension) existence. Yes, it sounds crazy! But it may very well be true that extra dimensions exist, and if so, the detection of a micro blackhole would prove this theory.
To quickly examine the possibility of extra dimensions, envision the following scenario: You are a stunt performer, walking along a tightrope tied between 2 buildings. Because you can only walk back and forth (or you’ll fall), you can only walk linearly, or one-dimensionally. Now imagine an ant crawling along the tightrope. This tiny little guy will be able to move back and forth, and also around the rope (left and right), which is movement in 2-dimensions. In this example, a significantly smaller ant was able to interact with more dimensions than you.
This same theoretical principle may similarly hold true for quantum-sized blackholes, which could be concealed by tiny unseen dimensions coexisting with our own. As of right now, such extra-dimensional existence is undetectable, but astrophysicists are dying to test the theory and gain definite answers.
In fact, the production of mini-blackholes to prove extra dimensions has actually been attempted in 2010 by the Large Hadron Collider, the world’s most powerful particle accelerator. Protons were smashed together at insanely high energies in the hopes of creating quantum blackholes. Unfortunately, none were ever detected, but experiments continue to intensify, possibly reaching the necessary threshold of energy to unlock extra dimensions - and tiny blackholes as proof of their existence - in the very near future!
There is one final quantum blackhole theory that will blow your mind entirely, guaranteed! It predicts that tiny blackholes exist all around us. In space. Invisible. But there. This is the dark matter theory of quantum blackholes - by far the most spine-chilling theory in astrophysics. If you are unfamiliar with dark matter, here are some quick facts: it is unobservable, doesn’t interact with light, and accounts for nearly 85% of all matter in the universe. Dark matter’s existence is indirectly verified by the behavior of stars and galaxies. The dark matter, like normal matter, exerts a gravitational field which interacts with other space bodies. So, dark matter is invisible, undetectable, abundant, and gravitational. Sounds an awful lot like quantum blackholes, doesn’t it?
The current information on this theory is rather vague since it was so recently formulated but you can watch this video which provides a more thorough explanation:
One thing that is certain about the quantum blackhole-dark matter theory, is that, if proven true, all of our current knowledge of the universe would be ultimately altered. And the crazy notion of quantum blackholes existing all around us will become fact rather than fiction.
That being said, let’s hope the theoretical department makes some headway with quantum black hole theory in future experiments!
Geometry and Properties of Blackholes
I'd like to start off this geometrical discussion by clearing a common misconception. Despite their name, blackholes are not "holes" by any means. A hole is generally associated with a 2-dimensional structure, which blackholes are definitively not.
In reality, blackholes are spherical 3-dimensional bodies. Think of the shape of a star.......a ball right? Yes - and blackholes are no different when it comes to this basic geometric
structure! They are the collapsed stars. If you reason logically, the chances of a 3-D orb-shaped star morphing into a 2-D hole are solidly zero.
Then why the misleading name?
To answer this question, we must take a quick venture six decades backward in time to the 1960's when Princeton physicist John Wheeler coined the official term, "blackhole". At that time, no veritable proof of blackholes existed, rendering the concept purely theoretical. However, astrophysicists were able to accurately predict the behavior of blackholes by extrapolating known data related to the mass of stars. "Blackhole" was more so used to describe the behavior of the body, since matter which is gravitated past the event horizon is permanently sucked into the central singularity, similarly to an object falling into a hole. Therefore, think of "hole" as a metaphor for what the blackhole does rather than what it is.
To further understand a blackhole's geometric structure and resulting properties, let's examine the concept of escape velocity. This is the speed a certain object would have to reach in order to escape the gravitational pull of another mass. For example, rockets must reach a specific threshold of speed in order to break through Earth's gravity and "escape" into space. This same idea applies to all matter in the presence of gravity. Escape velocity is dependent on two factors: the mass and radius of the larger body. Mass and radius work inversely to influence the speed of escape. The greater the mass and the smaller the radius, the higher the escape velocity will be (rendering escape more difficult) and vice versa.
There's a certain radius for every mass which yields an escape velocity equal to the speed of light. This is called the Schwarzschild radius (SR), and is a very useful tool for classifying masses as either blackholes or stable objects. For example, on Earth, a light-speed escape velocity occurs at a mere 9 millimeters in radius. (assuming the entire current mass of the Earth is condensed). Anything lower in radius than Earth's SR is automatically classified a blackhole because not even light will be able to escape the ultra strong gravitational pull of such a dense body.
We can now apply the properties of escape velocity and SR to redefine a blackhole's event horizon. Remember how we call it the point of no return? That not even light escapes beyond this boundary? This means that the outermost visible section of the event horizon measured to the central singularity equals the blackhole's SR. Anything even a thousandth of a thousandth of a millimeter closer to the singularity can no longer emit light.
This characteristic of an SR explains why astrophysicists can clearly detect the event horizons of blackholes but nothing from within. The event horizon is therefore, a blackhole’s strict boundary between visible and invisible (aka the SR).
*To clear another common misconception, the event horizon is not a physical barrier, meaning you won't be able to feel any difference compared to the outside when passing through, other than witnessing time distortion. The boundary can be more accurately defined as a barrier of communication, where nothing from within and outside can interact.*
So we can’t see anything past the event horizon. Sounds simple enough, right? Now take that thought to an entirely different level by questioning what exactly we will see, if say, a space ship is entering the blackhole.
You may be tempted to think that you will see the spaceship traveling all the way to the event horizon, and once it enters, nothing will be seen. Spoiler alert! Although in a general understanding, this reasoning is correct, there's a whole lot more to it…..
In reality, if you were observing that spaceship’s trajectory towards the blackhole, it would appear to be moving slower and slower as it approached the event horizon due to the warping of spacetime that greatly slows light speed. A decreasing light speed means each photon (light particle) coming from the blackhole is stretched to longer and longer time intervals apart from others. As the spaceship nears the horizon, the length of time between each individual photon becomes incredibly large, meaning the light that we detect as observers will take significantly longer to reach us. Possibly billions of years! At the point right before entering, that last photon will take a near-infinitely long amount of time to travel. The trajectory we observe from outside is an increasingly slowing spaceship until it comes to a complete stop in spacetime. That freeze will signify the last observable location of the spaceship before crossing the point of no return. However, this illusion of time pause will not remain present forever. Since the final photons reach us in more spread-out time intervals, we will observe a gradual fade of the spaceship until it is no longer detectable because the final photon has arrived.
Despite the visuals seen by outside observers, the spaceship’s perspective is quite contradictory. The ship physically enters the event horizon and at ever-increasing speeds is forced downward into the infinite singularity, where its atoms are ripped apart by a process called spaghettification. This event paradox is both extremely strange and extremely helpful when trying to comprehend the properties of blackholes at a deeper level.
If you’re wondering what the spaceship would see inside the event horizon, your answer is a bunch of light attempting to escape, and never succeeding. Meanwhile, everything that takes up space follows a unidirectional path toward the center of the singularity. Essentially, the roles of time and space are reversed in this absurd environment. (This reversal of spacetime to timespace will be covered thoroughly in a future article).
As I warned you at the beginning of our intensified discussion, blackholes are insane creatures! Which makes them so much more intriguing to learn about doesn’t it?
The Greatest Warpers of Spacetime
In case the concept of spacetime is unfamiliar to you, it is the combination of the three spatial dimensions and the one existent time dimension. Don’t worry - it’s more simple than you think! Envision a bird flying across the sky. It is interacting with spacetime because it exists in 3-D space while time moves forward as it flies. The same goes for a block sitting on a table for even a millisecond - three spatial dimensions and a forward progression of time are involved.
Back to blackholes. Just like any body with mass, blackholes warp the fabric of spacetime.
For a moment, think of our universe as a infinite, gridded blanket lying straightened in a vertical manner. Now if you drop all the masses of the universe (stars, planets, blackholes, etc), your blanket becomes a mesh resembling a shooting target pierced by a tremendous quantity of bullets. Well, that’s exactly what our universe is - a fabric that is deformed everywhere mass exists. Even the mass of a floating bacteria exhibits this warping effect, but on such a minute scale that it is generally unnoticeable.
The mass-imposed curving of spacetime, by the way, is the accurate representation of gravity according to Einstein's Theory of General Relativity. All objects with mass exert gravitational force, or, in other words, deform spacetime by creating curvature which all passing masses must physically follow. For example, near a planet, a free-falling comet will not be able to simply woosh past at a close distance. The comet must obey the curvature of surrounding spacetime, and will either align into orbit or strike the planet.
As we all know, larger objects have greater gravitational effects. Our sun imposes such a large curvature that our entire solar system revolves around it, while a tree branch on Earth bends spacetime enough for an ant to be gravitationally attached while crawling upside down.
Blackholes, as we mentioned earlier, possess masses anywhere from tens to billions of times greater than that of our Sun. That means the extensiveness to which they deform the fabric of spacetime is incredulously large as well.
The properties of time within such a region of curvature are quite astounding. From the outside perspective, an object slows to a freeze upon entering the blackhole. However, from the perspective of an observer within the blackhole, the entire universe appears to be moving in fast-motion! Essentially, time is delayed significantly within a blackhole, or perhaps, is greatly sped up on the outside. There is no fundamental speed of time progression so either consideration is equally valid depending on the observational perspective chosen.
As for space deformation, we are already familiar with the fact that space condenses into an infinitely dense point within the blackhole. Space becomes a one-way ticket while time turns multidimensional.
Evaporation Kills the Beast
Like everything that comes into existence, blackholes must also reach an end. This fact however, was unknown until Stephen Hawking's discovery of a concept he named Hawking radiation (sincerely speaking, the man was an extraordinary genius, so a bit of selfishness in the naming process is justified). Due to the significant quantum involvement in Hawking radiation, we will delve into the intriguing behavior of blackhole evaporation in the following article...... so stay tuned!
An end with new beginnings!
As the current article is gearing to a close, I'd like to say that I haven't even covered a fraction of the properties and behaviors of blackholes. There is so much more that you can learn about these mysterious entities, some examples including binary blackhole systems, spinning blackholes, white holes, wormholes, and countless more!! I am beyond ecstatic to share all the information I know through upcoming blog posts. In the meantime, if you are curious about novel discoveries relating to blackholes or any similar topic, stay up to date on the latest astrophysics news, projects, and observations. The field surely never ceases to amaze us all!
Additional Content
Here are some insanely intriguing YouTube videos about blackholes created by incredibly talented astrophysicists:
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