Just an invisible entity of universe which can swallow anthing inside it ?
who discovered balck holes ?
Black hole was just a hypothetical theory before scientist all around the globe made us witness the real picture of a supermassive black hole that is there
in the centre of Messier 87 (M87) galaxy (54 million light years away from us). We got the image with the help of 8 telescopes that were placed at different
angles all around the world , about 200 scientists worked on it and we got the picture of the supermassive black hole in April 2017 which also proved that
black holes do exist and cosmo agencies started digging more facts about black holes.
What is a black hole made of ?
Well this increases your curiosity about black holes , did you ever heard about death of a star ?
If yes , then you already know the answer . A black hole is formed when a massive star that is having a huge mass explodes and dies.
Actually a star is consist of hydrogen and helium molecules , that keep resulting into nuclear fusion but after billions of years when these molecules are
exhausted from a star it starts producing carbon in it and starts expanding ,( it is estimated that when our Sun will be closed to its death , its size will be
increased so much that it will take Mercury and Venus inside it and will come much closer to Earth ) now you can feel the intensity of expansion of a star ,
after expanding to an extent the star explodes its mass in the space and the gravity and pressure acts so much that remaining mass of the star is compressed
into a small nucleus which is extremely small in size as compared to the Star when it was alive but possess heavy mass into that small size. This nucleus gets
compressed in its own and becomes an extremely heavy element that even changes the space and time around it and makes singularity , this region possess extreme
gravity and hence it is said that black hole swallows eveything.