Eventually, as the universe ages, the material around a black hole will run out and its doomsday clock will start ticking. As a black hole evaporates, it slowly shrinks and, as it loses mass, the rate of particles escaping also increases until all the remaining energy escapes at once.
Black holes aren't, strictly speaking, entirely black. In pure general relativity, with no other modifications or considerations of other physics, they remain black for eternity. Once one forms, it will just hang out there, being a black hole, forever.
If black holes evaporate under Hawking radiation, a solar mass black hole will evaporate over 1064 years which is vastly longer than the age of the universe. A supermassive black hole with a mass of 1011 (100 billion) M ☉ will evaporate in around 2×10100 years.
The singularity at the center of a black hole is the ultimate no man's land: a place where matter is compressed down to an infinitely tiny point, and all conceptions of time and space completely break down. And it doesn't really exist. Something has to replace the singularity, but we're not exactly sure what.
New black hole simulations that incorporate quantum gravity indicate that when a black hole dies, it produces a gravitational shock wave that radiates information, a finding that could solve the information paradox. Perhaps the most enigmatic objects in the Universe, black holes embody many unsolved paradoxes.
Logically, these giant black holes—each millions to billions of times heavier than our sun—must collide and merge, too. Such mergers can channel huge volumes of material into the black holes, sparking violent astrophysical outbursts that shape star formation and other processes in their host galaxies.
Black holes have two parts. There is the event horizon, which you can think of as the surface, though it's simply the point where the gravity gets too strong for anything to escape. And then, at the center, is the singularity. That's the word we use to describe a point that is infinitely small and infinitely dense.
The closest black hole to Earth is a stellar mass black hole just 1,600 lightyears away called Gaia BH1. The black hole has set a new record for the closest known black hole to Earth.
It turns out that there is a theoretical limit to the size of black holes — celestial objects so massive that even light cannot escape them. And the largest directly observed black hole with a confirmed mass is right around this limit. This monster, appropriately named TON 618, weighs roughly 40 billion solar masses.
on edge of Black Hole. Space and time are intertwined, called space-time, and gravity has the ability to stretch space-time. Objects with a large mass will be able to stretch space-time to the point where our perception of it changes, known as time dilation.
Stellar black holes are very cold: they have a temperature of nearly absolute zero – which is zero Kelvin, or −273.15 degrees Celsius. Supermassive black holes are even colder. But a black hole's event horizon is incredibly hot. The gas being pulled rapidly into a black hole can reach millions of degrees.
Since nothing can escape from the gravitational force of a black hole, it was long thought that black holes are impossible to destroy. But we now know that black holes actually evaporate, slowly returning their energy to the Universe.
At the center of a black hole the gravity is so strong that, according to general relativity, space-time becomes so extremely curved that ultimately the curvature becomes infinite. This results in space-time having a jagged edge, beyond which physics no longer exists -- the singularity.
Roughly 1 trillion years from now, the last star will be born. In about 100 trillion years, the last light will go out. The bad news is that the universe is going to die a slow, aching, miserable death. The good news is that we won't be around to see it.
For most space objects, we use light-years to describe their distance. A light-year is the distance light travels in one Earth year. One light-year is about 6 trillion miles (9 trillion km). That is a 6 with 12 zeros behind it!
It is thought that the matter that goes into a black hole gets crushed into a tiny point at the center called a "singularity". That's the only place that matter is, so if you were to fall into a black hole you wouldn't hit a surface as you would with a normal star. Once it's there, it's there.
Most stellar black holes, however, are very difficult to detect. Judging from the number of stars large enough to produce such black holes, however, scientists estimate that there are as many as ten million to a billion such black holes in the Milky Way alone.
While researchers have never found a wormhole in our universe, scientists often see wormholes described in the solutions to important physics equations. Most prominently, the solutions to the equations behind Einstein's theory of space-time and general relativity include wormholes.
Because space isn't curved they will never meet or drift away from each other. A flat universe could be infinite: imagine a 2D piece of paper that stretches out forever. But it could also be finite: imagine taking a piece of paper, making a cylinder and joining the ends to make a torus (doughnut) shape.
Wormholes are a classic trope of science fiction in popular media, if only because they provide such a handy futuristic plot device to avoid the issue of violating relativity with faster-than-light travel. In reality, they are purely theoretical.
Like part of a cosmic Russian doll, our universe may be nested inside a black hole that is itself part of a larger universe. In turn, all the black holes found so far in our universe—from the microscopic to the supermassive—may be doorways into alternate realities.
No human has ever been inside of a black hole. Humans are not yet capable of interstellar travel. Even if a human was able to travel to a black hole, he or she would not be able to survive entering it. Black holes condense all the matter that falls into it into one point called a quantum singularity.
Fortunately, this has never happened to anyone — black holes are too far away to pull in any matter from our solar system. But scientists have observed black holes ripping stars apart, a process that releases a tremendous amount of energy.