The Space & Beyond Blog
If an astronaut fell into a black hole, they wouldn’t have a peaceful ride. They’d be stretched out like a noodle. Photo: Astronaut: NASA; Black hole illustration: NASA/ESA and G. Bacon (STScI)
Why you can’t survive falling into a black hole
Falling into a black hole would tear your body apart through “spaghettification.” But exactly how depends on what type of black hole you fell into.
If you tried jumping into a black hole, then you’d be ripped apart long before you could find out what’s on the other side. But to fully understand why you can’t dive into a black hole, you must first understand the basic properties of these gravitational goliaths.
What is a black hole?
Simply put, black holes are places where the gravity is so strong that nothing can escape. Black holes are aptly named because they usually don’t reflect or emit light. They’re only visible when they’re feeding on stars or gas clouds that stray too close to their boundary, called the event horizon. Beyond the event horizon lies a truly minuscule point called a singularity. This is where the laws of physics as we know them break down, meaning all theories about what lies within the singularity are just speculation.
Types of black holes
There are a few different types of black holes, so if you were to jump into one, your exact fate would depend on which sort of black hole you chose. At the simplest level, there are three kinds of black holes: stellar-mass black holes, supermassive black holes, and intermediate-mass black holes.
Stellar-mass black holes form when the largest stars exhaust their fuel and collapse in on themselves. Supermassive black holes live in the centers of most galaxies, and are thought to grow to their extreme sizes — up to tens of billions of times more massive than our Sun — by consuming stars and merging with other black holes. Intermediate-mass black holes are still mysterious, and only a few suspected examples have been discovered, but astronomers think they may form through a similar process of accretion, just on a smaller scale.
Scenario 1: Falling into a stellar-mass black hole
Stellar-mass black holes are puny in comparison to their bigger cousins, but they actually boast the strongest tidal forces of any type of black hole. That’s because smaller black holes actually have a more intense gravitational gradient than larger ones. That means you only have to get slightly closer to a small black hole to experience an extremely noticeable difference in gravity.
As you floated through space toward a stellar-mass black hole, you’d be stretched in some directions and squished in others, a process that scientists call spaghettification. This is because the black hole’s gravity compresses your body horizontally while pulling it like taffy in the vertical direction. So, if you jumped into the black hole feet first, the gravitational force on your toes would be much stronger than that pulling on your head. Each bit of your body would also be elongated in a slightly different direction. You would literally end up looking like a piece of spaghetti.
Scenario 2: Falling into an intermediate-mass or supermassive black hole
In contrast to falling into a stellar-mass black hole, your experience plunging into an intermediate-mass or supermassive black hole would be slightly less nightmarish. Although the end result — a horrible death — would still be your fate, you might actually make it all the way through the event horizon and manage to start falling inside the singularity itself while still alive.
In this case, at least in theory, you could see out into surrounding space. But no one would be able to see you once you passed beyond the event horizon. Even if you were holding a flashlight and tried to shine it out, the light would fall back down into the singularity with you.
Meanwhile, you’d see that everything within the event horizon was warped by extreme gravitational forces, thanks to an effect astronomers call gravitational lensing. (Not to mention the wild time dilation effects.)
Death by black hole
Of course, no matter what type of black hole you plunge into, you’re ultimately going to get torn apart by its extreme gravity and die a horrible death. No material that falls inside a black hole could survive intact.
Unfortunately, because nothing can escape a black hole’s event horizon — not even information — we’ll never know for certain what happens when matter falls past the point of no return. So, even if you do find yourself with the opportunity to take a cosmic cliff dive into a black hole, for safety reasons, you probably should resist the urge.