You black holes They are not really “holes”, but rather gigantic concentrations of extremely dense matter concentrated in very small volumes.
These structures are named after their ability to have such strong gravity that it traps everything, even light, beneath their surface, called event horizon . Since there is no emission of electromagnetic radiation, every observation we make of a black hole is indirect, via X-rays, gravitational waves or visualization of its accretion disk (a type of cloud formed by various elements that rotates around the black hole).
The notion of a surface itself is not entirely accurate, since the event horizon is only a theoretical boundary where the speed of gravitational release exceeds the speed of light. In practice, this means that an astronaut in a moving spacecraft would see the event horizon as far away, and could become trapped after crossing an “invisible boundary.”
What are the types of black holes?
There are two types of black holes in the Universe, and the difference is only in the size of the mass. The most basic is the stellar black hole which arise when a massive star runs out of fuel and implodes under its own gravity. Although difficult to detect, they can number in the hundreds of millions in our galaxy alone.
The second type is the supermassive black hole resulting from the successive fusion of several black holes into a single, massive structure. Still not fully understood by science, these giants can have billions of times the mass of our Sun. They are located at the center of galaxies and feast on other stars and gas from their surroundings.
O TON 618 the largest black hole discovered to date, has a mass equivalent to 40 billion times that of the Sun, or 20 times the size of our Solar system . With its immense outer rim rotating at half the speed of light, it circles once every three Earth months, while extrasolar planets orbit once every 250 years.
What would happen if we fell into a black hole?
After American astronomer Andrea Ghez and German physicist Reinhard shared the 2020 Nobel Prize in Physics with legendary British physicist Roger Penrose, we learned that right here in our cosmic backyard, there is a supermassive black hole. The so-called Sagittarius A* (Sgr A*) It is located right in the center of the Milky Way, has 4.3 million solar masses, and is approximately 26 thousand light years from our planet.
Even though this large mass of Sgr A* represents only a fraction of the total mass of the Milky Way (which is about 1.5 trillion suns), one might worry about one day having to face a black hole, knowing that nothing can escape them.
Speaking about this unlikely experience, Stephen Hawking explained, in his book “A Brief History of Time ”, that the person would go through a process of “spaghettification”. If he fell on his feet, he would feel a much stronger force in the lower part of his body, which would stretch, like the famous spaghetti, until it completely disintegrated into atoms and subatomic particles.
But if you fell into a supermassive black hole like TON 618, you might actually survive. That’s because gravity there is strong, but the stretching force is not. The bad news is that the event horizon is the edge of the abyss from which nothing, and no one, escapes.
Another question that may arise for Earthlings is whether Sagittarius A* could pose any risk to our planet. Mirian Castejon, a doctor in astrophysics and astronomer at the Ibirapuera Park Planetarium in São Paulo, says she considers it unlikely that the black hole poses a danger to Earth today, but warns: “In the very distant future, the Milky Way will collide with the Andromeda galaxy and possibly the central black holes of the two galaxies will merge,” she says.
On the other side of the black hole
According to Castejon, although these massive objects are constantly monitored by several telescopes, “perhaps the biggest question is about what happens to the matter inside a black hole and how supermassive black holes came to be.”
As for the concept of a wormhole, a tunnel in space-time predicted by Einstein’s equations of general relativity, which could supposedly connect a black hole to an analogous white hole, astrophysicists are skeptical. “There is no evidence whatsoever,” Castejon sums up in CNN .
Source: CNN Brasil
Charles Grill is a tech-savvy writer with over 3 years of experience in the field. He writes on a variety of technology-related topics and has a strong focus on the latest advancements in the industry. He is connected with several online news websites and is currently contributing to a technology-focused platform.
