Even though black holes cannot be seen, we know they are present from the way they impact nearby stars, dust and galaxies. Most of them are surrounded by discs of material. As the discs swirl around them like a whirlpool, they become very hot and produce X-rays.
Black holes come in a variety of sizes. Many of them are just a few times more huge than the Sun. These stellar mass black holes form when a heavyweight star, about 10 times weightier than the Sun, ends its life in a supernova explosion.
We keep hearing about these mysterious and strange things in space known as black holes, however have you ever thought what they are actually? Do they exist in reality or are they simply fiction?
Here are some interesting facts about black holes:
1. It was John Mitchell who actually first proposed the idea of object or dark stars. Later, in 20th century the word black hole was coined.
2. If the formation of a black hole has taken place, it can continue to grow by absorbing additional matter.
3. Black holes are actually leftovers of former stars and are so dense that nothing can flee from their dominant gravitational energy.
4. There are mainly three types of black holes namely supermassive, stellar and miniature black holes, depending on their mass.
5. Generally the life cycle of most of the stars end up being a white dwarf or a neutron star, but, black holes are considered to be the last evolutionary stage in the lifetime of a star.
A black hole forms when any object reaches a specific critical density and its gravity leads to it to collapse to a nearly infinitely small pinpoint. Stellar mass black holes form whenever a massive star can no more generate energy in its core.
With the radiation through its nuclear reactions to maintain the star puffed up, gravity leads to the core to collapse. The star's external layers may blast away into space or they may drop into the black hole to create it heavier. Astronomers are not certain how supermassive black holes form. They might form from the collapse of huge clouds of gas or from the mergers of numerous smaller black holes or a mix of events.