“Even light is not capable of escaping”

A black hole is a cosmic body that even light is not capable of escaping. Black holes cant be seen directly, but because of the gravitational fields around it, people then could tell where a black hole has been found.

One of the first persons to discuss the existence of black holes based on the laws of gravity was French scientist Pierre-Simon Laplace. The more massive an object, or the smaller its size, the larger the gravitational force felt on its surface. According to Hubble Site, “He argued; if an object were either extremely massive or extremely small, it might not be possible at all to escape its gravity. Even light could be forever captured.”

John Archibald Wheeler was the first person to introduce the name “black hole” in 1967. Black holes have become a favorite subject for science fiction writers. Although, black holes are not fiction, the way black holes form is whenever massive but otherwise normal stars die. We cannot see black holes, but astronomers could still sense stuff falling into them. What astronomers have done to measure the mass of black holes is by studying the sky. 

Black holes aren’t just one type, so far there are four type of black holes known. According to National Geographic, it states, There are four types of black holes: stellar, intermediate, supermassive, and miniature. The most commonly known way a black hole forms is by stellar death. As stars reach the ends of their lives, most will inflate, lose mass, and then cool to form white dwarfs. But the largest of these fiery bodies, those at least 10 to 20 times as massive as our own sun, are destined to become either super-dense neutron stars or so-called stellar-mass black holes.”

Actually, there is one black hole in our Milky Way galaxy. This black hole is a supermassive black hole and it is known as Sagittarius A or Sgr A. The distance between this black hole and the earth is estimated to be roughly about 36,000 light years. One light year also equals a total of 37,200 human years. The mass of the supermassive black hole Sagittarius A is 4.6 million times that of the sun. According to Constellation Guide, it states, “ Sagittarius A has a diameter of 44 million kilometres, roughly equalling the distance from Mercury to the Sun (46 million km).”