By: Urvashi Balasubramaniam
A star will die
when its core surrenders
to gravity's relentless force
in its blatant defeat
there is nothing left
to fuel its withering course
A star will die
never silently, yet in
exploding colour in its void of a realm
a primordial vibrance
before the obscuring whelm
A star will die
its old soul a lesser moiety
of its true existence
tearing atom from atom
any soul who ventures too close
in vengeful impiety
A star will die,
become the pivots of galaxies
swallowing pure light
its morbid allure
a flawless ethereal mystery
shrouded in its ghostly asperities
A star will die
its phantom dark and vengeful
but its purpose it cannot abandon
and even when the beacon
becomes a reaper
in its destruction, it is a creator
in its engulfment, a wonder
its memories etched
onto its cautioning horizon
A star will die
and in its death
teach us more about
than its fractured rays ever could.
A star is the result of a balance between gravity pushing in on it, and the nuclear fusion that occurs in the core of the star (Hydrogen fusing to form Helium) and releasing energy. When the balance of radiation and pressure tips ever so silently, the star begins its downfall.
"The core burns hotter and faster while the outer layers of the star swell by hundreds of times, fusing heavier and heavier elements. Carbon burns to Neons for centuries, Neon to Oxygen in a year, Oxygen to Silicone in months and Silicone to Iron in a day. And then, death. Iron [formed last] is nuclear ash. It has no energy to give and cannot be fused"
via Neutron Stars – The Most Extreme Things that are not Black Holes
Stars die in supernovae, which are beautiful explosions of light and colour that shine brighter than entire galaxies. After this explosion of light, the star becomes a black hole. A black hole is a complete contradiction to a supernova, isn't it? One emits radiant and majestic light, and the other swallows it.
(Via NASA) Cas A: the supernova remnant that was Chandra's "First Light" image.
Black holes swallow everything that passes their event horizon, the black hole's boundary. Unlike a vacuum cleaner, they don't pull in everything around them all the time. They do, however, have a strong attractive force of gravity. As you go closer to the event horizon, the pull of gravity accelerates your movement. The event horizon is the point of no return. Once you cross it, you are torn up into your constituent atoms. Yikes.
The further away you are from the gravitational singularity, the black hole's centre, the longer you'll live. Unfortunately, you can't explore a black hole unless you visit one, and since the event leads to certain death, you can tell why we haven't yet undertaken the journey.
While black holes may seem like far-off mysteries, they are fairly common. They occur at the centre of every galaxy, including ours! Good old Milky Way has a light-swallowing, supermassive black hole about 27,000 light-years away from us. The good news? It's way too far away from us to do any harm.
The bad news? Black holes can do many other nasty things to thriving civilisations. For example, a black hole travelling too close to the Solar System could attract planets away from their orbits, and far away from the warm, life-inducing light of the Sun. Also, if we collide with another galaxy, the earth could be pulled into a black hole, and The Andromeda Galaxy is predicted to collide with the Milky Way in about 4 billion years.
Are you filled with existential dread yet? Don't be. We haven't encountered a black hole in billions of years, and we aren’t likely to in the next few trillions and billions either.
(Via NASA) The first-ever image of a black hole captured by the Event Horizon Telescope
The fact that black holes are too far away to wipe out humanity has a lot of other benefits too. We can analyse them, for example, and learn about incredible scientific phenomena in these obscure dead stars. Black holes may have created the Universe, according to theoretical physicist Raj Pathria.
They've also thrown a logical conundrum our way, namely the Information Paradox. This paradox states that quantum information, the stuff that tells our atoms to be a part of a human and not a taco stand, can be destroyed in a black hole. Quantum information consists of things like the atoms' spin, position and velocity. However, quantum information can neither be created nor destroyed, so what's going on here?
Scientists have many theories that solve the Information Paradox. What if the information wasn't destroyed, but just existed inside the black hole? We've never really been there to check, so the theory holds. The most interesting theory is what is popularly called 'Hologram Theory'. It states that all that information is encoded onto the black hole's event horizon, so it never really gets lost, and the information never really enters the black hole at all. The object still exists inside the black hole, but it looks two-dimensional from the outside. So, theoretically, the quantum information of our atoms could also be encoded on some hypothetical Universe boundary, making us holograms.
This theory makes even more sense when you learn that when a black hole swallows an object, it grows in size a little. Could it be growing to accommodate more quantum information? It could, so the laws of physics are once again intact!
Except, there's another threat. There's also something called Hawking Radiation, the only known thing capable of annihilating a black hole. Black holes shed particles from their event horizons, but extremely slowly. In over a Googol years (that's 10^¹⁰⁰ years), the black hole will self-destruct. So does the information get destroyed too? That’s what we don’t know yet.
But what we do know for sure is that black holes are fascinating. By studying these far-off, planet-eaters' effects, we can learn a whole lot about our lives and our place in this tremendously vast and magical Universe.
TedED: Hawking's black hole paradox explained - Fabio Pacucci
TedED: Could the Earth be swallowed by a black hole?
TedED: Fabio Pacucci: Can a black hole be destroyed?
Kurzgesagt: Neutron Stars – The Most Extreme Things that are not Black Holes
Physics.org: Where is the closest black hole?
Kurzgesagt: Why Black Holes Could Delete The Universe – The Information Paradox
Kurzgesagt: Black Holes Explained – From Birth to Death