Whenever we hear the word Black Hole, the first thing that pops in our mind is Stephen Hawking and according to him, “Not only does God play dice, but he sometimes throws them where they cannot be seen.”
A black hole is a region in space where gravity pulls to an extent that even light cannot escape. The gravity is so powerful because matter is compressed into a little space. This may occur when a star dies. We cannot see black holes due to the fact that light cannot get out. Space telescopes with special tools can help identify black holes. These tools can view how stars that are very near to black holes are different than other stars.
How Big Are Black Holes?
Black holes may be either big or small. According to scientists, the smallest black holes are as small as an atom. These are very small but have the mass(amount of content in an object) of a mountain.
A different type of black hole is stellar whose mass can be upto 20 times greater than mass of the sun. There can be many stellar black holes in Earth’s galaxy which is known by the name Milky Way.The biggest black hole is known as ‘supermassive’, and their masses can be 1 million suns together. According to Scientists, every large galaxy includes a supermassive black hole in the center. This supermassive black hole which exists in the middle of the Milky Way galaxy is known as Sagittarius. Its mass is same as about 4 million suns.
How Do Black Holes Form?
According to studies, Primordial black holes are considered to have formed in the early universe soon after the big bang. Stellar black holes were produced when the middle of a massive star collapsed by itself. This collapse also created a supernova or an exploding star that blasts part of the star in the space.
According to scientists, supermassive black holes were made at the same time as the galaxy. The size of the supermassive is relevant to size and mass of the galaxy it lies in.
How Do Scientists Discover Black Holes When They Are Black?
The black hole cannot be seen due to powerful gravity pulls all the light in the center of the black hole. But, scientists can view how the powerful gravity affects the stars and gas surrounding the black hole. When a star and a black hole are near together, high-energy of light is developed. This type of light cannot be seen with human eyes, and scientists use telescopes and satellites to view the high energy light in space.
Is There Any Danger To Earth From Black Hole?
Black holes do not move around in space swallowing planets, moons and stars. Earth will not drop into a black hole because no black hole is near enough to the solar system.
Even if black hole of similar mass as sun were taken to the place of sun, Earth would not fall in. The gravity of black hole would be the same as sun and Earth would revolve the black hole as it orbits the sun.