The Terrifying Sound Of A Black Hole | Unveiled

The Terrifying Sound of a Black Hole

Of all the objects in the entire universe, perhaps none are quite so mysterious, ominous, or just plain strange as a black hole. These bottomless pits of infinite mass reign totally supreme over all around them. They’re ruthless and inescapable, as the threat of being drawn into one carries an ever-present promise of cosmological doom. Thanks to recent advances, though, we can today photograph these things to see them as they really are… and also, for the first time ever, we can now hear them, as well.

This is Unveiled, and today we’re exploring the terrifying real sounds of a black hole.

Should you ever find yourself approaching the event horizon of a black hole, then you’re facing an impossibly terrible situation. You’re about to be drawn into the spectacular void and there’s nothing you can do about it. You’re going to be spaghettified into nothingness; the very atoms that make up your body will be pulled apart and essentially dissolved; and even the fundamental structure of time itself is about to fail you, as the laws of physics capitulate. Nevertheless, in the modern age, black holes actually aren’t completely off limits to us. We’ve arguably learned more about them in just the last few years than at any other time before. And thanks to pioneering work by NASA, we’ve finally switched them off mute.

In the summer of 2022, NASA broke new ground with black holes by releasing an audio clip of the sound emitting out of the center of the Perseus Galaxy Cluster. As often happens with such vast structures in space, we know that at the heart of the Perseus Cluster there’s a huge black hole, anchoring everything in place. It’s a vital region of the universe, too, as Perseus ranks as one of the biggest and most massive objects anywhere in existence. There are literally thousands of whole galaxies moving around here, with each one containing millions of stars, planets, asteroids, other, smaller black holes, and other objects. It’s perhaps little wonder, then, that even something as immeasurably immense as a black hole should creak and whine under all that pressure.

Indeed, in the short, 30-second clip produced by NASA, it might be said that there’s a feeling of power. Of titanic force. And of mechanisms so vast that they’re beyond comprehension. But there’s undoubtedly an eerie quality to the recording, as well. A looming darkness, and maybe even a sense of dread. It’s as though what we’re hearing is the universe itself stirring… and the very fabric of reality bending, flexing, and rippling through the abyss. Ultimately, it also sounds like an effect you might hear on something like “Doctor Who” or “Star Trek”... only this isn’t science fiction anymore, it’s the real deal.

But still, there are some key aspects of the black hole sound to keep in mind. Officially, NASA presents the Perseus pulse as “Black Hole Sonifications With a Remix”, which is significant. NASA explains a sonification as a “translation of astronomical data into sound”. What we’re actually hearing, then, while they are true sound waves, they’ve been modified so as to fall within the range of human hearing. According to NASA, they’ve been scaled upward “by 57 and 58 octaves above their true pitch” which, NASA further explains, means that the strange sound that we recognise is actually between 144 and 288 quadrillion times higher than the original frequency. If, then, you were to ever find yourself approaching the event horizon of this particular black hole (and by some miracle you still had all your senses intact) then this sonification technically isn’t what you’d hear. Not exactly. Although the same soundwaves would still be flooding all around you.

Those sound waves - the astronomical data that has now been translated for our ears - were first detected by the Chandra X-Ray Observatory, and it’s been known that Perseus is quite a “noisy” place in general since the early 2000s. Perseus is blanketed in hot gas, which is what provides a medium through which its sound can travel. Remember, there are thousands of galaxies here, with each of them doubling up as colossal moving parts, speeding through space something like an unfathomably huge engine. In the notes accompanying the release of the audio clip, NASA takes the opportunity to remind us that while it’s commonly held that there’s no sound in space… this isn’t actually true. And Persus is proof of that. So long as there’s something for soundwaves to penetrate, then sound happens just the same as anywhere else… and it’s only in the vacuum of space (the chasms of genuine nothingness between galaxies) that “no one can hear you scream”.

So, where do we go from here? Ultimately, it might be argued that the black hole sound doesn’t provide science with a great deal of new information. After all, we already had this data on the page and on our screens, we already knew how sound and energy pulsed rhythmically from the Perseus Cluster, it’s just that now we can truly comprehend that in audio form. In their natural state, we still remain effectively deaf to black holes because the tones that they send out do not register with our auditory senses… but still, even a generation ago, would we have imagined that we’d now be able to listen in to these things? Probably not. It’s a mark of just how far we’ve come in our quest to understand space. And it’s a prime example of just how detailed our studies are beginning to get.

This is not the same black hole as that which was famously imaged for the first time, by the Event Horizon Telescope in 2019. However, NASA has released some audio clips to accompany that black hole, too - the one at the center of the Messier 87 galaxy. Making use of x-ray, optical, and radio waves, the sonification this time around sounds to human ears much more musical. It has been processed differently to the Perseus Cluster data, and perhaps gives a more alternate representation of the real sound… but even so, there’s again a feeling of the rise and fall of space. Of a universe that’s truly alive.

Stuck on our planet with more than enough to worry about, it can be easy to forget everything else that’s happening all around us, all the time, beyond Earth’s atmosphere. But these clips bring it all back home. So what’s your verdict on NASA’s black hole sound? Are you inspired by what you’ve heard, or kinda terrified? Does that distant whirring ignite your curiosity, does it specifically remind you of anything else, or will it just become the haunting soundtrack to your next nightmare? Whichever side you fall onto, it’s got the whole world talking!