Scientists have recently discovered the origin of supermassive black hole flares, which is a significant breakthrough. A supermassive black hole flare is the orbiting material that surrounds black holes in the form of an acceleration disk near the black hole’s equator. Scientists have suggested that a magnetic reconnection powers this flickering. The news on supermassive black hole flares inspired me to write further on these peculiar objects and include “dark matter.”
Karl Schwarzschild was the first scientist who predicted black holes in 1916 with the help of his genius colleague, Albert Einstein. However, the term “Black Hole” was coined by an American astronomer named John Wheeler. It remained as a theory for 55 years, and the first physical black hole ever discovered was spotted in 1971, and the first image of a black hole was taken in 2019.
So, what are black holes? In simple terms, a black hole is a region of spacetime. Spacetime is a mathematical model that fuses the three dimensions of space and one dimension of time into a singular four-dimensional manifold where gravity is so strong that not even light or any radiation can escape from its grasp. The theory of relativity predicts that a sufficiently compact mass can deform spacetime to form a black hole. A black hole is formed by a massive star’s death (a star dies when it has exhausted its internal thermonuclear fuels in its core).
Black holes have three “layers”: the outer and inner horizon and the singularity. The event horizon of a black hole is the boundary around the mouth of the black hole, past which light cannot escape. Once a particle crosses the event horizon, it cannot leave. Gravity is constant across the event horizon. The inner region of a black hole, where the object’s mass lies, is known as its singularity, the single point in spacetime where the mass of the black hole is concentrated.
So far, astronomers have discovered 3 types of black holes: stellar black holes, supermassive black holes, and intermediate black holes.
- Stellar black holes populate the universe, and they devour small stars, dust, and gas from their surrounding galaxies. They have masses ranging from 5 to several tens of solar masses.
- Supermassive black holes dominate the universe. These black holes have several million to billions of times the mass of the Sun. After formation, they gather mass from the dust and gas, materials that are plentiful in the center of galaxies, allowing them to grow to even more enormous sizes. Supermassive black holes could also result from hundreds or thousands of tiny black holes that merged. These black holes also hold galaxies together. For example, our milky way galaxy has a black hole in the center holding everything together. These galaxies with supermassive black holes in the center form spiral galaxies.
- Intermediate black holes are midsize of black holes. They form when stars in a cluster collide in a chain reaction. They have a mass of 100 to 1000 solar masses (no single star can form such a heavy black hole). Several of these forming in the same region could eventually fall together in the center of a galaxy and create a supermassive black hole.
Black holes are fascinating objects. The “theory of the multiverse” states that black holes could be wormholes that are portals to other universes. It says you can even go back in time. Of course, we can always make up our own theories and leave things to our imagination, on what lies after the singularity of a black hole.
Another equally interesting topic is “Dark Matter,” which I intend to cover in my next blog. If you like this one, please comment and share your views. They will help me do better and motivate me to write further.