Remember those times in the 5th grade when even a star twinkling brighter in the sky caught your attention? When you had numerous questions piling up in you regarding the “evening star”? When the mere mention of the big bang was enough to spread crazy-roots all over your brain? Yet, notwithstanding advancements in science, a lot more remains unanswered. The biggest mystery in the celestial domain remains black holes. Starting with their discovery and innumerable hypotheses revolving around them, their nature is yet to be fully understood. Believed to be caused when a star collapses in on itself after a supernova (death of a star), following few facts that are currently known about black holes are sure to set off a ticking bomb in your grey matter!
10. THEY WERE ACTUALLY DISCOVERED BY JOHN MITCHELL
Although the theory of black holes received a boost with Einstein’s theory of general relativity, it was actually in 1783 when John Mitchell came up with the idea of black holes. Drawing from the theory that light consists of particles called photons, he hypothesized that the immense gravitational attraction of stars might impact the amount of light leaving their surfaces. Thus, after a supernova, when the star died, the gravitational force went up by an incredible amount which prevented light from escaping any longer. Even if light once goes into a black hole, it can’t escape it (as we so commonly know today).
9. BLACK HOLES CAN BE MIND-BLOWINGLY MASSIVE AND NOTHING CAN ESCAPE THEM
Worry not. The nearest black hole to Earth is 1600 light years away. Quite a distance even for Superman to travel! You might be wondering that mind-blowingly massive is an exaggeration. It’s not. There are black holes that are more than 1,000,000 times the mass of our very own Sun! And that is just the beginning. Heavier black holes have also been found to exist. Black holes are known to travel at great speeds and things get a wee-bit more chaotic when they collide- in other words, they increase in size! And you thought the Sun was gigantic, huh! As for escaping from the clutches of a black hole, it is theoretically impossible. Owing to the physics-defying gravitational pull light, once trapped in a black hole, cannot escape. Theoretically speaking, light would bend around the event horizon and finally get trapped inside the black hole.
8. SPACE GETS DISTORTED AROUND THEM
Whatever physics your teachers taught right from the lowest to the highest grade become horse-crap in and around a black hole. Light bends, time stops, density becomes infinite! As I mentioned earlier about black holes being insanely heavy, they also happen to be insanely dense. Any matter that has the misfortune of falling into a black hole would be crushed to an infinitesimally small size; in other words, its density would approach infinity (as volume tends to zero!) and is also believed to be broken down into its sub-atomic constituents! The distortion of space and time, collectively known as space-time, takes place at the event horizon which is the border of a black hole. Time is dilated (that is, it slows down greatly) and matter is compressed to zero volume. However, it is to be noted that black holes do not act as celestial vacuum cleaners; i.e, unless one is within a solar radius’s length from a black hole (or anywhere very close to the event-horizon) it is going to have no effect.
7. BLACK HOLES ARE NOT NECESSARILY DESTRUCTIVE
Although this will be very tough to digest (after all the distortion facts), there have been numerous studies and hypotheses that suggest that the energy from black holes (yes, they do emit electromagnetic radiation! Which is why they can be detected) can actually be harnessed for power and space travel. Energy produced by black holes is said to be 50 times more efficient than nuclear fusion.
6. BLACK HOLES MIGHT BE RESPONSIBLE FOR LIFE
This might actually prove to be a wild jig on your brain- scientists have gone to the extent of saying that black holes might also be the very reason that you are sitting, boogy-eyed staring into the glowing screen of your desktop/laptop/cell phone and I am writing this for you to read. In other words, as black holes break down matter into its subatomic constituents, these particles may have the ability to create elements such as carbon, nitrogen that are necessary for LIFE to exist.
5. BLACK HOLES ARE NOT OF A SINGLE TYPE
The moment we hear the term ‘black holes’, a picture of dark nothingness slips into our mind. Reality, however, is starkly different. Astronomers and scientists have shown that black holes come in different variations- spinning black holes, electrical black holes and those kinds of talented black holes that are spinning as well as electrical! Spinning black holes are believed to be formed when two regular black holes collide with one another. Due to this reason, their distortion of space-time is significantly higher than the regular ones and thus, emit greater amount of energy. A black hole, called the GRS 1915+105 is known to be spinning more than 950 times per second.
4. BLACK HOLES ARE NOISY
This might come as a slap-in-the-face fact. Well, whatever happened to the sound-cannot-travel-in-vacuum stuff that one learnt in one’s tender years? Well, strictly speaking, the “noise” generated isn’t really from sound waves. Special instruments designed for detection of radiation from black holes reveal a crackling, static-like noise. The explanation? Owing to the immense gravitational pull of the black hole, the event horizon increases the speed of the particles multiple folds and this is, in turn, responsible for producing the sound. In the year 2003, astronomers in NASA were able to detect ‘sound waves’ coming from a supermassive black hole (almost 250 million light years away).
3. BLACK HOLES LIMIT THE NUMBER OF STARS IN THE SKY
Many scientists believe that the number of stars in the universe is determined by black holes. So the next time you’re up with your beloved counting stars and drawing weird patterns in the sky, you have a humongous mass (that ‘sucks’ incredibly) to thank! Delving into a little bit of science, the particle jets that black holes are known to emit expand into bubbles and sear through the regions in the galaxy where stars are formed. Such regions are filled with gas clouds that form stars on cooling down. But if these regions get affected by the particle jets they heat up and thus, star formation is prevented.
2. WE ARE LIVING INSIDE A BLACK HOLE
Now this has got to be one of the most atrocious things science can say to us. Although not a mainstream science theory (more fringe science) physicists have long observed that the mass-energy density of the universe (taken as a whole) is roughly equal to that of a black hole. Although largely inconclusive, this has planted the wild seed of imagination into the minds of many a scientist. It is hypothesized by many scientists that the black hole that our universe is in (supposedly) is the part of yet another universe and the black holes that exist in our universe are merely gateways to parallel universes! And you thought physics was boring! Huh!
1. TIME DILATION TAKES PLACE
Going into the nitty-gritties of this aspect, it seems almost a fantastical claim that time can actually slow down! But that is exactly what happens at the event horizon. Hypothetically speaking, let’s say a clock survives its fall into a black hole. To observers outside, it would appear to have slowed down as it approached the event horizon although, to the clock itself, it would be functioning normally. Gradually, once inside the black hole, the clock would have stopped completely. Time dilation had been explained by Einstein in his general theory of relativity. The gravity of the black hole is considered to be so strong that it can stop light altogether.