The black holes are, probably, the most mysterious, fascinating and terrifying planetary body of the whole univere. A body with a such dense mass and a such intense gravitational field that it leaves no way to anything around it. However, do we really know the black holes, do we know how they were born and how many things do we know about them? But especially did you know that there are many types of them? Let’s discover them together.
What’s a black hole
A black hole is “a celestial body with a such intense gravitational field that it leaves no way to nor matter neither electromagnetic radiation, which meas that, under a relativistic point of view, it’s a region of the space time with an enough big warp that nothing from the inside can escape, not even the light”.
Basically nothing that enters inside a black hole can go out anymore. Not even the light, not even the matter. And the black hole is invisble, for this reason. It can be detected as a space completely empty, usually a point where once back in time there was a star. A point around which the gravitational force is very high, as much as that the celestial body around it were all “catched” and they now rotate around it at a very high speed, close to the light ones.
The black hole is such powerful that it distorts the space time, so to not let nothing escape. It is a door from which we can enter but we cannot leave. What’s there inside the black hole? No one knows it. The hypothesis are so many, but the truth is that the black hole is the most mysterious celestial body of the whole universe.
How many types of black holes are there?
We don’t know a lot, in reality, about this mysterious celestial body. But we know that there are many types of them. The astrophysics classified five of them.
The black holes are different between each other for their mass, from the which how they were born, from their “age”.
But we aren’t sure they really exist neither. We found some of them, other we had just hypothized. We “saw” some of them. Or better, we believe they are there, in that unspecified point of the universe. But is there for real?
Primordial black holes
The primordial black holes, as the name itself says, they are the most ancient. An ancestral celestial body. And that’s really the most incredible and weird celestial body. Yes, because if we think about a black hole we think about something incredible big, as big as many stars or tens of planets.
But the black holes are, in reality, small, much smaller of what we can imagine. One thinks, infact, that they have a diameter of only some centimeters, or even less.
A black hole such small that it can be only born in the very first moments of live of our universe. Right after the big bang, when the density didn’t have yet the “rules” of today. When in the primordial soup there were peakes of very high density. And it was right there that this very small black holes might be born.
But the primordial black holes are just a theory. One thinks, infact, that there is one of them in the edge of our Solar System. But they are too small to be detected. To hypothized them it was Stephen Hawking.
Star Black Holes
The star black holes are the most common and known. They are the ones born when a star die. When the star finishes the nuclear fusions, because of the end of the fuel, it collapses in a supernova, and then it “dies” into a star black hole.
Middle Black holes
There are the star black holes and the supermassive ones, the difference is the mass. The problem is that no one ever observed black holes with a medium mass. However, they must exist, somewhere.
The black holes pass from a starry mass to a mass of tens of billions of times the size of the Sun (the supermassive that we will see soon). However there must be a middle phase.
The point is that no one ever see it. But there are many hypothesis about it. The most likely is that this phase is very short in time.
The middle black holes might have, according to the astrophysics, a mass from hundreds to thousands suns.
Let’s now talk about the supermassive. This kind of black hole, with a super massive mass, is very common and it’s the only one we were able to capture in picture”.
Their mass is huge (it goes from millions of solar masses to hundreds of billions). In the middle of the Milky Way there is a supermassive black hole, which captures with its gravitational force all the galaxy, by making it rotates around it.
We think that every galaxy has a supermassive in the middle.
Lastely, there are the Quasar, ancestral objects that wander to the edge of the universe, where the matter is ever more rarefied. The quasar are the last phase of a black hole. When a supermassive grows up its matter, by creating a bright disk around it. Its such bright that the quasar are the brigthest objects of the universe.
In reality we know so little about the black holes that we didn’t understand yet if the quasar is something that happens before the supermassive or after or if its a middle phase. We think even that the supermassive in the middle of our galaxy already passed from this phase, before to end its light and become a supermassive.
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