Black hole is a region in space where gravity is too strong, even light rays can get out because due to matter has been squeezed out into each available space in the region. This idea was given by John Michell in 1783 and later many scientists, including Stephen Hawking has explored the concept and given their ideas to this world. The first image of black hole is captured by Event horizon telescope(EHT) in 2019. EHT has made his mark in this world by releasing first image of black hole M87*. It present in centre of supergiant elliptical galaxy Messier 87
Black hole occurs during process of super nova. Supernova happens when pressure drops low enough in a star, gravity of the star suddenly takes over and star collapses in just seconds and produce large shock and heat waves. Black hole varies in size according their stars during super nova, larger black holes are categorized into stellar and largest one are categorized as supermassive black holes. Studies show that core of the star is transformed into black hole during the explosion. Black holes are not visible to naked eyes and because it does not emit any light rays. Only space telescope with special tools can discover black holes. The special tools can show us how stars that are very close to black holes act differently than other stars in the galaxy
If a black hole is black how we identify it in space?
Black hole is black due to strong gravity that pulls all the light into centre of the black hole. But it identified with a special tool which used to study gas of stars. Scientists can see how strong gravity affects the star and gas around it. Scientists can study the stars to find out if they are orbiting a black hole or flying around. When a star is closer to the black hole that particular star emits high energy lights is made. This kind of light cannot be seen with naked eyes. Scientists use satellites and telescope in space to see the high energy light
Can Sun become a black hole?
Not all star will collapse at some stage and turns into a black hole. only the star with larger radius about 2 to 4 solar masses will form black hole when it collapses, but there are not certain masse above that star will be turned into a black hole. But another way around any object that collapses to the point where its radius less than a certain limit must ultimately become a black hole. This radius is called the Schwarzschild radius, and it's given by the equation
Where M is mass of the object, G is gravitational constant and c is the speed of the light
Sun is not a big star to form a black hole. Even in a worst case scenario if the sun turned into a black hole it will not suck the earth into it because black hole will have the same gravity as the sun, so simply our earth revolves around the black hole. But the life system in earth will become extinct due to the absence of sun light
Nearest Black hole to earth
Scientists, except they were 100 million black holes roam around stars in our milky way galaxy, but they were not identified as a conclusive black hole. But the nearest black hole to earth is Sagittarius A which categorized into super massive one and it lies at the centre of our galaxy. It takes 25,640 light years to reach from earth. But recent searches show nearest isolated stellar black hole to earth might be as close as 80 light years away.
Sound of black hole
But recently NASA has released the audio clip of black hole which obtained from black hole in the Perseus galaxy cluster. Scientists discovered that the pressure waves sent out by black hole cause ripples in the cluster's gas create sound but the actual sound is cannot hear by human. So NASA has amplified the sound and mixed the noise which we hear has an eerie sound like in horror ones. There are certain things in the universe which we know little about them and there thousands of things like black hole let to discover in this universe
