Black holes are probably some of the most terrifying specimens of astronomy existing in the universe. The gravitational pull of black holes is so overwhelmingly strong that even light cannot escape their relentless tug! Black holes are essentially defined regions in spacetime from which absolutely no radiation or particle can flee; this powerful gravity arises from the infinitely large density of the body. A black hole is so dense because there is an enormous amount of mass concentrated into an almost inconceivably minuscule volume. Amazingly, it has been speculated that our car keys can become a black hole of its matter is compacted to the size of an atom or electron- it will then possess the mass of the key, but this mass will be centralized to a single point. So, due to this huge density, there will an immense gravitational pull, which will subsequently absorb everything in its vicinity, even light.
There are different types of black holes. The first type are stellar black holes, or “collapsars”. These black holes are known to be “the possible evolutionary endpoints of high mass stars”, as defined in Cosmos. These “high mass stars” are typically over twenty times the mass of our sun, whose life ends in an explosive supernova before creating a black hole. These black holes have a mass of about 5 to 10 solar masses.
The second types are supermassive black holes, which have masses equal to billions of solar masses; these are the bodies that are said to exist at the center of each galaxy—indeed, a supermassive black hole is known to exist in the Milky Way Galaxy as well. However, due to their distance and elusive properties, scientists and astronomers have still not reached a consensus regarding their formation. As reported in Cosmos, it has been conjectured that “supermassive black holes form out of the collapse of massive clouds of gas during the early stages of the formation of the galaxy”. Another hypothesis speculates that stellar black holes consumed its surrounding matter over millions of years, thereby expanding to the proportions of a supermassive black hole. Scientists know that these types of black holes are even in existence due to the extremely high acceleration of matter revolving around the core of galaxies- their high orbital velocities could only indicate that they are spinning around a relatively small object with a gargantuan amount of gravitational force.
The last types of black holes are called miniature black holes; however, there is no solid evidence that they actually prevail in the universe. Miniature or micro black holes are said to contain a massive amount of matter contained in an infinitesimally small point; moreover, their event horizon (the theoretical boundary surrounding a black hole after which nothing, not even light, can escape) is also theorized to be about the width of an atomic particle. These mini black holes weigh less than three solar masses, and are said to have been created due to the extreme, crushing density of the nascent universe (around the time of the Big Bang). All the same, we must remember that as fascinating as they seem, miniature black holes are still purely hypothetical. In fact, scientists have wondered whether the Large Hadron Collider (the largest machine and most powerful particle factory in the world) is creating mini black holes while it operates, since “each particle beam the collider fires packs as much energy as a 400-ton train traveling at about 120 mph (195 km/h)”.
Black holes are undoubtedly some of the most enigmatic astronomical objects humanity is cognizant of. In fact, we can’t even see black holes, since not even light can leave once it reaches the hole’s event horizon! – We can detect black holes because of the impact they have on their neighbors. For instance, a black hole may consume the contents of a nearby star; this process can be caught by X-rays. Nevertheless, as described in Universe Today, black holes are like creatures in a cage- they’re powerless as long as a body stays away from the event horizon. Additionally, when matter crosses the event horizon and is consequently swallowed by the black hole, the hole actually increases, thereby strengthening its gravitational force and making it all the more powerful. Black holes also have strong, noticeable effects on the passage of time. Once a body crosses the horizon, it will be subjected to the gravitational forces of the black hole, which will hence make it travel at incredibly high speeds. So, these high speeds cause time to slow down.
The fascination humans have regarding black holes is reflected in popular media, such as in films and books. Famous examples are the movies Interstellar, Event Horizon, and in the show Battlestar: Galactica. And this interest is not groundless, since black holes are indubitably one of the most intriguing and mysterious entities in the entire universe.