Supermassive Black Holes
Thanks to recent advancements in technology, astronomers have been given the means to better understand how supermassive black holes formed, as well as their relation to the evolution of their respective galaxies. Before understanding what a supermassive black hole is, it is probably best to learn about normal black holes in comparison. A black hole is essentially a vortex containing a gravitational field that is strong enough to prevent any form of matter or radiation from escaping it. As the name suggests, a supermassive black hole is the extended version of a normal black hole, meaning it's the same just bigger in size.
Scientists and astronomers not only believe that these are the largest black holes in existence, but that they exist at the center of every galaxy as well, including our own. Not only are they the largest forms of black holes, but they also are the largest objects to exist in the universe in terms of mass. Scientists also believe that the gravitational pull they have is far too strong for anything to escape it, including light, making them practically invisible. Regarding the evidence of these black holes' existence, there are many theories that lead to an explanation for the formation and purpose of these supermassive black holes.
The original black holes are thought to exist since the creation of the universe, which is known as the Big Bang. They destroyed whatever they could, swallowing anything and everything that came within it's gravitational pull, but would also create using all of its absorbed energy. Their size is unimaginable, containing anywhere from millions to billions of times the solar masses that the sun has. As stated previously, these black holes exist at the center of every galaxy including the Milky Way, but it was recently discovered that the size of the supermassive black hole's mass has a direct correlation with the size of its host galaxy's mass. Researchers discovered a relation between the mass of all the black holes and the center of their galaxies known as the bulge. They can also live in what is known an inactive galaxy, meaning the black hole is dormant like an animal in hibernation, taking breaks in between feeding periods. All it takes is for one lone star or gas cloud wandering too close to wake up and activate the black hole. ""...the black hole will awaken, become active and release vast amounts of energy and potentially lethal radiation that reverberates throughout its galaxy."" (""A Singular Place"").
Astronomers had only collected indirect evidence for the existence of these supermassive black holes for a number of years. Some examples of this evidence would be things such as quasars, galactic jets, and even materials in space such as stars and gas. Quasars are what are known as the brightest objects in the universe and are thought to be powered by supermassive black holes. The light they produce forms from the friction of materials swirling around the black hole's surrounding accretion disk. Studies on quasars reveals that they produce over a trillion times as much energy as the sun from a small portion of space, leaving supermassive black holes as the only possible source for this power. However, quasars are not the only phenomenons to be created from these giant beasts. Galactic jets, which can span millions of light years in length, are also produced by supermassive black holes. When the surrounding magnetic fields and accretion disk interact, it forces out a jet that mostly consists of electrons and positrons. ""This interaction simultaneously releases energy from the black hole, and constrains the direction in which it can leave the system, funneling it all into collimated jets."" (""Galactic Jets""). The most recent evidence comes from the high orbital velocities of materials in space, like stars and gas. Their acceleration can simply be explained if they are being pulled by a strong gravitational field that is confined in a small area. In other words, the definition of a supermassive black hole.
There is a lot more to that these black holes are responsible for however. Not only do they power things like galactic nuclei, jets, and quasars, but they were and still are essential to the evolution of their galaxies, as well as the universe. Galactic jets for example, are thought to have produced the first starlight throughout space. This means that these supermassive black holes most likely existed prior to their galaxies, giving them something to revolve around upon their creation. So technically in the long run, they are responsible for the creation of the sun and even our own planet. Another thing they are known for is emitting naturally-occurring microwave amplifiers due to the water molecules in the accretion disk, known as masers. Masers allow researchers to make more precise estimations on the distance between earth and other galaxies. They can also cause galaxy mergers, which is essentially when two galaxies collide together. These mergers were thought to have significantly benefited universe evolution, being that the universe was much more crowded upon its creation compared to today.
Due to recent research provided by scientists and astronomers, it is safe to say that these supermassive black holes more than likely exist, and are also necessary for our universe to continue growing. They have given us a better understanding as to why and how they exist. Whether it be from stars that died millions of years ago and slowly evolved into a massive black hole, or collapsed dense gas clouds mixing with other materials in space. Their research has also revealed to us the impact they have had on our universe. Certain impacts could be the way it looks, the arrangement of stars and planets, and even the mass of its host galaxy. With growing advancements in research and technology, the future could hold further answers in this area of work. They could potentially discover the way these supermassive black holes are truly formed, as well as the impact they have on the evolution of the galaxies they inhabit.
References
Astronomy.swin.edu.au. (2018). Supermassive Black Hole | COSMOS.
Retrieved from: http://astronomy.swin.edu.au/cosmos/S/Supermassive+Black+Hole
Astronomy.swin.edu.au. (2018). Galactic Jets | COSMOS.
Retrieved from: http://astronomy.swin.edu.au/cosmos/G/Galactic Jets
Frolov, V. P., & Zelnikov, A. (2011). Introduction to black hole physics.
Retrieved from: https://ebookcentral.proquest.com
Lasker, R., Ferrarese, L., van de Ven, G. and Shankar, F. (2018). SUPERMASSIVE BLACK HOLES AND THEIR HOST GALAXIES. II. THE CORRELATION WITH NEAR-INFRARED LUMINOSITY REVISITED.
Retrieved from: http://iopscience.iop.org/article/10.1088/0004-637X/780/1/70/meta
The Relationship between Black Holes and Galaxies. The Dumbbell Nebula (NGC6853,M27).
Retrieved from: www.cosmotography.com/images/supermassive_blackholes_drive_galaxy_evolution_2.html
Supermassive Black Holes. (2019, Jan 26). Retrieved from https://papersowl.com/examples/supermassive-black-holes/