Grade ( in English) : Grade Seven C [7-C]
Admission Number : 22422
Sandas Kevinda Nagahawatte
Black Hole
Black holes are mysterious objects through out of the universe. people believed to be science fiction in the 19 hundreds, however in 1971 it was proven to be real by Louise Webster and Paul Murdin. Definition of black holes are simple, an extremely dense object with a gravity which is so powerful that not even light can escape. This is the reason to name black holes black because they do not emit light. These extremely dangerous and blackish monsters are greedy. They don’t care what they eat, they just gobble anything in its path.
Black holes appear when a star a size of 20-3o goes supernova. Even though the outer parts from the core of the star is bounce back and keep expanding, the core continuous to collapse until for a point where it cannot be crushed anymore. At this stage the core weighs about 3-150 solar masses yet the size is same as a small city to a country. And the most interesting thing is when you go near a black hole your time slows down. That means if you call somebody far away from the black hole and you are near the black hole he would see you as like a slow-motion video, and you can see him like a hyperlapse video. Black holes are of two types
- Stellar mass- with a mass of 3 to 150 solar masses
- Supermassive- with a mass of millions to billions of solar masses
But the black hole in the picture is surrounded by a weird, glowing disk. What is this?
It is known as the Accretion Disk. It is the part which feeds the black hole. The accretion disk it’s made from all types of matter such as plasma, gas and etc. But these matter particles exist in subatomic particles. Even though these particles exist in their subatomic state because the disk is spinning the particles collide to each other creating friction. This friction builds up so much that the accretion disk begins to glow. Because the disk glows it’s harder to identify the black hole. Because of the collisions of the subato
mic particles not only heat and light emit but also X-rays. But in the above pictures we can see that the back of the accretion disk, this is because of the bending of space-time which makes the light rays go above and below the black hole.
Parts of the Black Hole
- Event Horizon
The event horizon is the part of the black hole which does not have a physical surface but has a mathematical surface. Scientists say that the materials falling into the black hole first pass the event horizon, which is also known as the point of no return.
- Singularity
The singularity of a black hole is kind of the place where the bending of the space-time ends. Some scientists think the singularity is an infinite dense point. And some, think that they are points where another universe might happen. But in reality, it is just a fancy name for saying “we don’t know”.
Sagittarius A*
Solar system is in a Galaxy named for the Milky Way. In galaxies there are a supermassive black hole in its center, just like in other galaxies our Milky Way has its own black hole. This is named as the Sagittarius A*. Supermassive black hole has a nickname of Sgr A*. This giant monster is 26,670 light years away and weighs about 4 million- 4.6 million solar masses. Discovered as a compact radio source in the 1970s and confirmed by the early 2000s by tracking the orbits of stars around it.
A photo taken by the Event Horizon Telescope of Sagittarius
Ton 618
TON 618 is a hyper luminous quasar in the constellation Canes Venatici that contains one of the largest known black holes, with a mass of about 66 billion solar masses. This ultra-massive black hole is so bright it outshines its entire host galaxy and is located roughly 18.2 billion light-years away, meaning the light we see left Earth’s solar system before it even formed.
An image of Ton 618
Phoenix A*
The largest black hole ever to be discovered. This giant monster it’s about 590,000,000 kilometers long and weighs about 100 billion solar masses. It is located in the phoenix cluster. Phoenix A lies about 5.8 billion light years away from earth. And it interestingly it grows about 60 suns per year. This black hole is a true Titan between us.
