Black Holes The Secret World of the Cosmic Vacuum

Black holes are among the strongest and most amazing things in outer space. It is so dense, with gravity so strong that even light cannot escape its grasp if it gets close enough.

Deep within the infinite sky lies a cosmic mystery that has intrigued scientists and the public alike: black holes. These mysterious astronomical phenomena that represent black dots in the fabric of the universe, where they swallow light and are completed by darkness, challenge understanding and ignite the imagination of researchers. In this vast world, black holes are magical points that combine science and imagination, where people wonder about the secrets of supergravity and its strange effect on space-time.

Human knowledge and technology are accelerating toward understanding the depths of these phenomena, trying to decipher them and reveal their secrets buried in the depths of the distant universe. In this context, this article deals with an exploratory trip to the world of black holes, where we will delve into their concepts, and discuss recent developments in this field that attract attention and open a new horizon in our understanding of the universe and its secrets surrounding us.

Albert Einstein first predicted the existence of black holes in 1916, with his General Theory of Relativity. The term "black hole" was coined by American astronomer John Wheeler several years later in 1967. After decades of knowing black holes were only theoretical objects, the first physical black hole that was discovered was discovered in 1971.

Then, in 2019, the Event Horizon Telescope (EHT) collaboration released the first-ever recorded image of a black hole. The EHT saw the black hole at the center of galaxy M87 while the telescope was examining the event horizon or the region from which nothing can escape from the black hole. The picture depicts the sudden loss of photons (particles of light). It also opens up a whole new field of research into black holes, now that astronomers know what a black hole looks like.

So far, astronomers have identified three types: stellar, massive, and intermediate.

Stellar black holes - small but deadly

When a star burns up in its last fuel, the object may collapse or fall on itself. For smaller stars (those with a mass about three times the mass of the Sun), the new core will become a neutron star or white dwarf. But when a larger star collapses, it continues to compress and creates a stellar black hole.

Black holes formed by the collapse of individual stars are relatively small but incredibly dense. The mass of one of these objects is more than three times the mass of the Sun in the diameter of the city. This results in an enormous amount of gravitational force that pulls things around the object. The stellar black holes then devour dust and gas from the surrounding galaxies, keeping them growing in size.

Supermassive black holes - Giants are born

Small black holes fill the universe, but black holes like them, which are supermassive, dominate. Its massive mass is millions or even billions of times that of the Sun, but it has about the same diameter. It is believed to be located at the center of almost all galaxies, including the Milky Way.

Scientists are not sure how such large black holes are generated. Once these giant planets form, they collect a mass of dust and gas around them, abundant material at the center of galaxies, allowing them to grow to larger sizes.

Supermassive black holes arise from large groups of dark matter. This is a substance that we can observe through the effect of gravity on other bodies; However, we don't know what dark matter is made of because it does not emit light and cannot be directly observed.

Intermediate black holes - stuck in the middle

Scientists previously thought they only came in small and large sizes, but recent research has revealed that they may exist as intermediate or intermediate-sized ones (IMBHs). Such objects can form when stars collide in a cluster in a chain reaction. Many of these microorganisms that form in the same region could eventually clump together at the center of a galaxy to form a supermassive black hole.

In 2014, astronomers discovered what appeared to be a medium-mass black hole in the arm of a spiral galaxy.

New research, from 2018, suggested that these massive gaps may exist in the cores of dwarf galaxies (or very small galaxies). Observations of 10 such galaxies (five of which were previously unknown to science before this latest survey) revealed X-ray activity - common in black holes - indicating the presence of black holes from 36,000 to 316,000 solar masses. The information came from the Sloan Digital Sky Survey, which examines about a million galaxies and can detect the type of light often observed coming from black holes that capture nearby debris.

What do black holes look like?

Black holes have three "layers": the outer and inner event horizons, and the individual horizons.

The event horizon of a black hole is a border around the mouth of the black hole, past which the light can escape. Once a particle crosses the event horizon, it cannot leave. Gravity is constant across the event horizon.

Scientists can't see black holes the way they can see stars and other things in space. Instead, astronomers must rely on detecting the radiation that black holes emit as they pull dust and gas into the dense creatures. But supermassive black holes, which are in the center of the galaxy, may be shrouded in thick dust and gas around them, which can block the alarming emissions.

Sometimes, when the matter is attracted toward the black hole, it bounces off the event horizon and is pushed outward, rather than being pulled into the void. Bright jets of material are created by moving at near relative velocities. Although the black hole is still not visible, these powerful jets can be seen from great distances.

The Event Horizon Telescope image of M87's black hole (released in 2019) was an extraordinary effort, requiring two years of searching even after the images were taken. This is because the collaboration between telescopes, which spans many observatories around the world, produces an astonishing amount of data that is too large to be transmitted over the Internet.

Over time, researchers expect to image other black holes and build a repository of what these objects look like. The next target is likely to be Sagittarius A*, the black hole at the center of our Milky Way. A 2019 study reported that arc A* is interesting because it is quieter than expected, which may be due to magnetic fields stifling its activity. Another study that year showed that a cold gaseous halo surrounded Sagittarius A, giving unprecedented insight into what the environment around the black hole looks like.

Shedding light on binary black holes

In 2015, astronomers using the Laser Interferometer Gravitational-Wave Observatory (LIGO) detected gravitational waves from merging stellar black holes.

"We have additional confirmation of the existence of black holes with stellar masses greater than 20 solar masses—things we did not know existed before LIGO discovered them," David Shoemaker, a spokesperson for the LIGO Scientific Collaboration (LSC), said in a statement. LIGO observations also provide insights into the direction in which the black hole is spinning. When two black holes orbit each other, they can rotate in the same or opposite directions.

Under the second model, stellar-mass black holes sink into the center of the mass and double. These guys will have random spin directions compared to each other. LIGO's observations of accompanying black holes with different spin directions provide stronger evidence for this formation theory.

"We are beginning to collect real statistics on binary black hole systems," said Keita Kawabe, a LIGO scientist from the California Institute of Technology, based at the Hanford LIGO Observatory. "This is interesting because some models of black hole binary morphology are somewhat preferable to others so far, and in the future, we can narrow this down further."

Strange facts

• If you fall into a black hole, the theory has long suggested that gravity will stretch you like spaghetti, even though your death will come before you reach the singularity. But a 2012 study published in Nature suggested that quantum effects could make the event horizon look a lot like a wall of fire, which would instantly burn you to death.
• Black holes don't suck. Suction occurs by pulling something into a vacuum, which a supermassive black hole certainly does not. Instead, objects fall into it just as they would fall toward anything that exerts gravity, such as the Earth.
• The first thing considered a black hole is Cygnus X-1. Cygnus X-1 was the subject of a friendly bet in 1974 between Stephen Hawking and fellow physicist Kip Thorne, with Hawking betting that the source wasn't a black hole. In 1990, Hawking conceded defeat.
• Miniature black holes may have formed right after the Big Bang. The rapid expansion of space may have compressed some regions into small, dense black holes less massive than the Sun.
• If a star passes too close to a black hole, the star can be torn apart.
• Astronomers estimate that the Milky Way has between 10 million to a billion stellar black holes, with masses approximately three times the mass of the Sun.
• Black holes are still a great source for science fiction books and movies. Watch the movie "Interstellar," which relied heavily on Thorne to incorporate science. Thorne's work with the film's special effects team has improved scientists' understanding of how distant stars appear when seen near a fast-spinning black hole.

In conclusion

At the end of this amazing journey into the world of black holes, we realize that these astronomical phenomena remain mysterious symbols that tell the story of the universe and raise our questions about the nature of existence and space-time. Modern research and technologies have shown us new aspects of these dark astronomical objects, however, we still have many mysteries and challenges to explore.

Black holes remain a source of inspiration for scientists and enthusiasts alike, supported by their extraordinary influence on space-time and their wondrous effects on the cosmic ocean. Unraveling this astronomical mystery represents an ongoing challenge and an opportunity to understand the depths of the universe and its complex interactions.

In the end, black holes remain the subject of our wonder and wonder, as they represent a window to infinite worlds at the heart of the universe. In its deep analysis and understanding may lie the key to revealing new secrets regarding the nature of the universe and our future in this vast and amazing space.