ALL ABOUT BLACK HOLE [2020]

BLACK HOLE

In 1939, ROBERT OPPENHEIMER and H.SNYDER calculated that a star would have to be atleast three times as massive as a sun to form a black hole .

Most stellar black holes, however , lead isolated lives and are impossible to detect judging from the number of stars large enough to produce such black holes, however , scientists estimate that there are as  10 million to 1 billion such blackholes in the milky way alone.

 -  what is black hole ?

• Black hole are the strangest objects in the universe. a black hole does not have a surface, like a planet or star. instead, it is a region of space where matter collapsed in on itself. This catastrophic collapse results in a huge amount of mass being concentrated in an incredibly small area. A black hole hole is a region of spacetime exhibiting gravitational attraction so strong that nothing-no particles or even electromagnetic radiation such as light-can escape from it. the theory of general relativity predicts that a sufficiently compact mass deform spacetime to form a blackhole.

•  Black hole are generally defined as "a place in space where gravity pulls so much that even light can not get out . the gravity is so strong because [the] matter squeejedd into as tiny space." as light is unable to escape the holes gravity it appears completely black.therefore it is known as black holes.

• The event horijon telescope has captured a photo of a black hole at the center of M87, a galaxy 54 million light- years away

• This picture is taken over five days of observation in APRIL 2017 using eight telescopes, deoict liminious gas swirling around a supermassive black hole at the center of M87, a galaxy 54 million light years away

-How they formed ?
black holes generally formed when mass of a object compressed too much.
 For example--- when the earth compressed in the shape of a Football it becames a black hole..


-can we create a blackhole?
in principal, a black hole can have a mass equall to or above about 2.2 *10^-8 or 22 micrograms (the plank mass). to make a black hole one must concentrate mass or energy sufficiently that the escape velocity from the region in which it is concentrated exceeds the speed of light . thats may not be possible in todays generation .

• A black hole with the mass of the sun will last a wijened 10^16 years. considering that the current age of the universe is paltry 13.8 times 10^9 years, thats a good amount of time. but if you happened to turn the eiffel tower in to black hole it would evaparate in only about a day when the black holes would loose the rest of their mass in a short amount of time as abrupt explosions . we can detect these explosions as gamma ray bursts.