Black Hole and the Science Behind It

Imagine this picture. We will collect all 200 billion stars of the Milky Way and put them on a giant cosmic scale. On these scales will be our Sun, every smallest red dwarf, and every dazzling giant star found in the Milky Way. Throw in all the planets, why not, and all the satellites of you and me, everything. And on the other side, put just one specific black hole. And according to some reports, these scales will almost balance. It is about such a monster called TON 618 that we will talk today. According to known estimates, the mass of this black hole is 66 billion times the mass of our Sun. Okay. And now about the dimensions, that is, length and width.

Let's take our Solar System as a benchmark. If we take the distance from one edge of Pluto's orbit to the other, this segment would fit into the diameter of the event horizon of TON 618 more than 30 times. And somewhere out there is a tiny Earth, where we still argue about whether to consider Pluto a planet. I say: yes, why not, if it makes Plutonians happy. In other words, this diameter is the distance that light travels in two weeks. Fortnight! Light is the fastest phenomenon in the Universe, and we measure the size of this monster by the duration of your two-week vacation. But how does something like this even appear? Because the good old "She ate

a bunch of everything" explanation, as for regular black holes, seems a bit incomplete here. And what ultimately causes such a black hole to stop growing? After all, TON 618 is not just another space record holder. This object poses a much deeper question: how big can a black hole get? What sets the limit? And could the universe create something even more absurdly gigantic? When astronomers first noticed Ton 618, they thought it was just a dim blue star in our galaxy. A tiny speck of light. It appeared in a 1957 survey by the Tonantzintla Observatory in Mexico. Hence the abbreviation Ton. And 618 is simply the serial number of the object that they then found or added to their list. Hence the name.

Further observations showed what this point actually was. A supermassive black hole that feeds on matter. Matter falls into it and emits a tremendous amount of radiation, which is why it is also called a quasar. Its light traveled over tens of billions of years to reach you and me. So it definitely wasn't some neighboring star in our galaxy. And for an object at such a huge distance to shine so blindingly, it must be powered by some incredible engine. As I said, all this radiation comes from the matter surrounding the black hole. Gases and matter don't just fall straight down and disappear. They circle, forming what is called an accretion disk. And as all this gas spirals inward,

gravitational energy is converted into heat and radiation. The black hole itself remains dark, obviously, it is black. The very substance falling into it creates this light show. And in a quasar, this light can outshine an entire galaxy with billions of stars around it. When we try to photograph her, it's like photographing a crowd. Where some dude stands in the middle and shines a spotlight right into your camera. All those people are out there somewhere, you just don't see them much or at all. However, pulling this material into a black hole is more difficult than you might think, because the familiar picture of a cosmic vacuum cleaner

sucking everything in at once ignores something important. Namely, that objects can orbit around a black hole. Replace our Sun with a black hole of the same mass and the Earth would simply continue moving in the same orbit. Yes, daylight will disappear, all the plants will disappear and we will be in complete chaos. But we won't suddenly spiral into some cosmic downpour. So to create a monster like TON 618, it's not enough to simply have a lot of material nearby. This material needs to transfer some of its orbital momentum outward so that it can spiral inward. And when it does, it starts emitting radiation, which makes it harder to absorb the next batch of mass, because light can push on objects,

remember? Look at your desk lamp. It sounds wild, but it's true. Right now, its light is also exerting a tiny pressure on you. However, around a feeding black hole, this radiation can become so intense that it is enough to push away the gases and matter that gravity is trying to pull inward. Therefore, a certain balance must be found. This balance, this equilibrium, is called the Eddington limit. A kind of food speed limit. Although nature has ways to get around it under certain conditions. In short, here's what's important. This limit increases as the black hole becomes heavier. A larger black hole

has a stronger gravitational pull, so it can sustain a brighter food rush before the radiation starts to push matter away too much. And that means, just think about it, that growth can snowball. The more mass it gains, the faster it can gain more. Essentially, the bigger it gets, the more it can eat. This is how I understand diet. I would like one. So, a black hole that feeds continuously on this boundary can roughly double its mass every 30 million years. And this doubling continues. 100 suns turns into 200, then 400, then 800. Give this process enough time and the numbers will get really crazy. In theory, a black hole with a mass of a hundred suns could grow to the size of 618 tons in just

a few billion years. And we see tone 618 at a time when the universe was about 3 billion years old. So there is still time to spare. The biggest challenge is to translate these beautiful paper formulas into the realities of a real galaxy. The equation assumes that fuel is supplied continuously. In reality, the gas may simply dissipate, become new stars, or simply orbit infinitely without ever falling into a black hole. Supply support is a big part of the problem. But there is another opinion. Perhaps the black hole started out as a heavyweight. A huge cloud of primordial gas could have formed a massive seed, blazing like a short-lived supermassive

star that collapsed almost immediately. Instead of starting with 100 suns, you can start with tens of thousands or even more. And this is a fairly significant advantage. But there is one but. Very specific conditions are needed for all this gas to go into building a single monster and not scatter into ordinary stars. By the way, mergers can also help. When galaxies collide, their central black holes can eventually merge as well. This allows you to gain mass without having to pass each droplet through a gas disk. Although there may be problems with this. When two black holes merge into one, the uneven emission of gravitational waves can throw this newly formed single black hole away from the center. Sometimes it can be

thrown so far that it is thrown out of its home galaxy altogether. Congratulations, you've got a new, bigger black hole. Now go and find her. So there are recipes for creating such giants, and they can be combined. More massive nucleus, long-term feeding and black hole mergers. We still don't know the details of the past of tone 618, but modern physics perfectly explains that the appearance of such an object is quite possible. But that leaves the question we started with. Let's assume the fuel continues to flow. Suppose the black hole continues to grow. Does this process ever hit a wall? One of the ideas is both very strange and very cool. A black hole can become so massive that it can no longer

support the type of disk that made it such a super bright quasar. Imagine that shining disc again. Obviously, it needs to exist somewhere, but close to the black hole there is an inner boundary beyond which the gas can no longer move in stable circular orbits. He dives inside. And as the black hole becomes more massive, this limit moves further away. Then you need to make the disk bigger, right? But it's not that simple. Then another problem begins. Remember, gas has its own gravity, so it can then start clumping together and forming stars instead of remaining a smooth disk that feeds a black hole. And so there remains this zone between the two problems. Too close and the orbits become unstable. Too

far and the disc breaks into pieces. According to one theory, as a black hole grows, this safe zone eventually simply ceases to exist. There's nowhere else to put a normal, thin, brightly shining disc. Under these conditions, these calculations set the limit at about 50 billion masses of our sun. But, wait, didn't we just say that tone 618 could have 66 billion? And it powers the quasar. So what? We found a limit for something, and then immediately discovered an object that exceeds that limit? Well, the figure of 50 billion comes with certain conditions. How fast a black hole spins matters. And how the disks power it. So, if you take these conditions to the

absolute extreme, the model itself assumes a mass of up to an insane 270 billion suns. So 50 billion is more of a helpful hint than a strict cosmic rule that says, "You have to stop eating right here." But there is another complication. And now about those famous 66 billion. It's worth explaining how astronomers got this number in the first place, because as you can see, no one actually put the tone 618 on giant scales like we did at the beginning of the video. Unfortunately, we can't observe individual stars making neat orbits around it to simply calculate the mass, as we do for the Milky Way's supermassive black hole. TON 618 is just very, very far away from us. The only thing we can analyze is the radiation

from the fastest gas flow near the very center. Each element leaves its own characteristic mark in this light. In short, as the gas moves towards or away from us, these traces shift slightly. And because the gas moves at a wide variety of speeds, these traces blur. And this blurring gives astronomers a way to estimate how fast this gas is moving. They then use the quasar's brightness to estimate how far this gas is from the center. This speed and this distance together tell you how much mass is needed to keep all this in orbit. Overall, the basic idea is quite simple. How much gravity does it take to make this stuff move like that? The difficulty is that we're doing this with an object that's literally billions of light years away,

using gas whose exact location we can't see. If you change your calibrations a little, the answer may change too. That's why one estimate gives us about 66 billion of our suns, and a later analysis gives us about 41 billion. An error of 25 billion solar masses is no joke. For a standard deviation, this is simply a colossal number, no matter what we are talking about But the black hole did not lose this mass. Just a slightly adjusted method gave us a different estimate. Either way, we're still looking at something absurdly gigantic. Does this uncertainty matter if we try to rank it with other supermassive giants or if we want to understand

how close it is to the theoretical limit? But here's what seems more interesting to me than who wins the heavyweight title. The proposed limit concerns a black hole growing by absorbing matter beyond the accretion disk. However, a black hole can still gain mass through merging with another. So even if it outgrows the conditions that caused it to become like a quasar, that doesn't necessarily mean the end of its growth. It can still become bigger, much bigger, while losing that bright beacon that helped us find it. And this leads to a somewhat disturbing thought. Could there be black holes out there larger than 618 tons that just don't announce themselves to the entire cosmos so brightly and loudly? Potentially

yes, but they could exist, and we found one. These are two completely different things. We still need to catch her on something that can be measured. Fortunately, even a silent black hole has gravity. We can look for its influence on the motion of nearby stars. Or, when positioned correctly, the way its gravity bends and distorts the light from the object behind it. So yes, you can turn off the spotlight, but this mega-monster will still leave clues for us to find. So how big can a black hole get? Due to the bright disk feeding we talked about in the extreme conditions, some calculations put the upper limit at about 270 billion times the mass of our sun. That's about four times more than the

well-known estimate for 618 tons. And mergers could push those limits even further. So hundreds of billions of suns? Theoretically possible. We haven't found the final ceiling that nothing can ever exceed yet. But whatever it is, Tone 618 is definitely not the end of what physics allows. Just try to imagine these numbers in reality. We started with a giant that could fit three dozen of our solar systems across. And now we're looking at objects with a mass that's about four times that. Using the same simple size calculation, this means approximately the diameter. So, forget about 30. Now we're talking about over a hundred of our solar systems, lined up side by side to the orbit of Pluto, across from one damn

huge black hole. Remember the two weeks of light travel? Now you're looking at almost two months of light traveling from one end to the other for one single object. And there's one more thing about the Tone 618 that's easy to forget. We talked about her as if we were watching her right now. But that's not true. What we see is light reaching us now from a past 10 billion years ago, long before the Earth or the Sun existed. This monster was already huge in those days when our Solar System was not even in the draft. So what happened to what we see now? Who knows. It could grow even bigger, it could merge with other black holes, it could run out of fuel, and it could fade away like a shining quasar.

We just don't know. We can't rewind time and check. We only see its distant past, and information about more recent periods has not yet reached us. And the most amazing thing is that we learned all this from a tiny speck of light. Astronomers have split up this light, studied the clues within it, and found evidence for an object so massive that we need the stars of an entire galaxy just to make that number mean anything. In my opinion, this is real fantasy. Write in the comments what amazes you more: the sheer size of this thing, or the fact that we are able to learn so much about it from this tiny piece of light that traveled through the universe before our Sun even existed.

Anyway, thanks for watching. Like, subscribe to see more videos like this, and see you next time. See you later.