Answer: Black holes don't really “explode”, which implies that they generate a large outburst of energy which ultimately tears them apart, but they do have outbursts (also, unfortunately, referred to as “explosions”).
Scientists think that black holes eventually will explode, but it will take many, many times longer than the current age of the universe for that to happen.
The most common way that black holes cause explosions is not through their own self-destruction, but through the sheer power of their overwhelming gravitational force. Supermassive black holes sit in the centers of galaxies, and sometimes large clumps of matter, such as stars, pass too close.
Superhot particles ejected from the black hole would slam into our planet along with lethal levels of radiation. Once the x-ray and gamma-ray photons reach Earth, they would destroy the ozone layer within months.
At the center of our galaxy, a supermassive black hole churns. Learn about the types of black holes, how they form, and how scientists discovered these invisible, yet extraordinary objects in our universe. In their final stages, enormous stars go out with a bang in massive explosions known as supernovae.
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.
It is possible for two black holes to collide. Once they come so close that they cannot escape each other's gravity, they will merge to become one bigger black hole.
Eventually, in theory, black holes will evaporate through Hawking radiation. But it would take much longer than the entire age of the universe for most black holes we know about to significantly evaporate.
For example, a black hole of 1 solar mass takes 1067 years to evaporate (much longer than the current age of the Universe), while a black hole of only 1011 kg will evaporate within 3 billion years. Black holes are detected by observing high-energy phenomena and the motions of nearby objects.
If you leapt heroically into a stellar-mass black hole, your body would be subjected to a process called 'spaghettification' (no, really, it is). The black hole's gravity force would compress you from top to toe, while stretching you at the same time… thus, spaghetti.
We are in absolutely no danger from black holes. They're a bit like tigers – it's a bad idea to stick your head in their mouth, but you're probably not going to meet one on your way to the shops. Unlike tigers, black holes don't hunt. They're not roaming around space eating stars and planets.
Black holes are dark, dense regions in space where the pull of gravity is so strong that nothing can escape. Not even light can get out of these regions. That is why we cannot see black holes—they are invisible to our eyes. Because nothing can get out of black holes, physicists struggle understanding these objects.
The possibility that a black hole could actually impact Earth may seem straight out of science fiction, but the reality is that microscopic primordial black holes could actually hit Earth. If one did, it wouldn't just impact like an asteroid, it'd pass straight through the entire Earth and exit the other side.
Eventually, the entire contents of the universe will be crushed together into an impossibly tiny space – a singularity, like a reverse Big Bang. Different scientists give different estimates of when this contraction phase might begin. It could be billions of years away yet.
Any outgoing matter would collide with the matter in orbit, and the system would collapse into a black hole. "A long-lived white hole, I think, is very unlikely," said Hal Haggard, a theoretical physicist at Bard College in New York.
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.
Stellar black holes are very cold: they have a temperature of nearly absolute zero – which is zero Kelvin, or −273.15 degrees Celsius.
The most powerful supernova yet recorded (ASSASN-15lh) was 22 trillion times more explosive than a black hole will be in its final moments. It doesn't matter how small or how massive a black hole is, their closing fireworks are exactly the same. The only difference is how long it will take a black hole to explode.
The largest black hole ever found in the known universe is found in Ton 618. This is a hyper luminous Lyman-alpha blob that has a black hole that measures 6.6×1010 solar masses. It has a mass that equals about 66 billion times that of the Sun.
Because of their enormous, space-bending gravity, everything that falls into them is instantly ripped apart and lost. Scientists have never seen a black hole, because nothing, not even light, can escape them.
Inside what's known as the black hole's event horizon, not even light itself can escape from a black hole. But that doesn't mean that black holes will live forever; on the contrary, they slowly decay away due to a phenomenon known as Hawking radiation.
As black holes evaporate, they get smaller and smaller and their event horizons get uncomfortably close to the central singularities. In the final moments of black holes' lives, the gravity becomes too strong, and the black holes become too small, for us to properly describe them with our current knowledge.
Wormholes are shortcuts in spacetime, popular with science fiction authors and movie directors. They've never been seen, but according to Einstein's general theory of relativity, they might exist.
Located just under 1,600 light-years away, the discovery suggests there might be a sizable population of dormant black holes in binary systems. The black hole Gaia BH1, seen in this artist's concept near its Sun-like companion star, is the closest black hole to Earth discovered so far.
The short answer, unfortunately, is no. White holes are really just something scientists have imagined — they could exist, but we've never seen one, or even seen clues that one may exist. For now, they are an idea. To put it simply, you can imagine a white hole as being a black hole in reverse.