Today in questions you never knew you wanted the answer to: What’s a black hole sound like? Turns out, the depths of the darkest reaches of oblivion “sound” a whole lot like a video game, according to a NASA data sonification.
“Sound” is in quotes there because a sonification is not a literal audio recording, sent hundreds of millions of light years directly into YouTube’s compression algorithm. Rather, it’s the result of a technological process in which NASA takes its array of space data and then transposes it into a form the human brain can actually comprehend. Previous data sonifications have taken the form of soothing, ambient soundscapes. Some, like that of the Bullet Cluster—an extrasolar discovery that first proved the existence of dark matter—sound remarkably like a bonus track from one of Thom Yorke’s 71 side projects.
But a black hole—specifically, the black hole at the center of the perennially enigmatic Perseus Galaxy Cluster, a gaggle of galaxies some 240 million-odd light years away—is less fit to get pressed onto an LP. If anything, it’s aurally close to nothing, a persistent low hum that conveys unease and ominous emptiness.
Nailing down the sound of Perseus has long been a target of NASA’s interest.
“Since 2003, the black hole at the center of the Perseus galaxy cluster has been associated with sound,” NASA wrote in a press release. “This is because astronomers discovered that pressure waves sent out by the black hole caused ripples in the cluster’s hot gas that could be translated into a note. … The popular misconception that there is no sound in space originates with the fact that most of space is essentially a vacuum, providing no medium for sound waves to propagate through. A galaxy cluster, on the other hand, has copious amounts of gas that envelop the hundreds or even thousands of galaxies within it, providing a medium for the sound waves to travel.”
To create the sonification, NASA took those sound waves and scaled them up by nearly 60 octaves. The initial sound is so incomprehensibly low that we’re “hearing” it tuned up, at minimum, by 144 quadrillion times its actual pitch. (On the high end, NASA estimates that figure could be closer to 288 quadrillion; either way, there’s no way a human brain could even register an unmanipulated version of it.) This particular data sonification was first indexed in May, but the agency recently posted it again on social media over the weekend. Its most recent outing on the internet quickly attained supernova viral status. As of this writing, the clip has been played more than 8.9 million times.
People immediately started calling it things like “terrifying,” “unsettling,” “an Eldritch horror,” and “here’s a video of my dog barking after hearing it.” But others made the comparison to video games. (Three cheers for the gaming angle!) The obvious corollary is Mobius Digital’s tour de force, Outer Wilds, a high-minded space exploration game and a permanent fixture of Kotaku’s “best games” pantheon. Here’s the tune “Uncertainty Principle,” from Outer Wilds composer Andrew Prahlow:
Good thing our own universe survives longer than 22 minutes!
Others pointed out how it sounds exactly like the start of the Halo theme, and then actually superimposed the theme on top of NASA’s clip, an uncanny match. (Personally, I think it sounds a bit like the soundscapes from Observation, No Code’s psychological mind-fuck puzzle game from 2019.) And, of course, some folks likened the sound to the Reapers from Mass Effect.
If you’ll recall, BioWare’s totemic trilogy of extraterrestrial-banging RPGs was set against the backdrop of an imminent invasion from apocalypse death machines. These machines, called Reapers, lived in the fringes of space between galaxies. Every 50,000 years, they sweep through the Milky Way and purge sentient life. Reapers look like enormous purple un-fried calamari, but are marked more by the ominous, foreboding sound they make upon arrival—which sounds a whole lot like NASA’s data sonification of the Perseus Cluster’s black hole.
This brings us to the Fermi Paradox, a quandary notably put forth in the 20th century by Italian physicist Enrico Fermi: If space is so vast and so full of near-infinite possibilities, there’s no way Earth is the only instance of sentient life in the Milky Way, right? But also, where the hell is everybody?
There are tons of theories as to why either side of the argument could be right. (Wait But Why ran down all the leading ones nearly a decade ago, a thorough summary that still holds up today.) One popular theory reads exactly like a Mass Effect pitchline: The rest of the galaxy is quiet because there’s a predator species out there. All of the other advanced species are aware of these predators, and are silent as a result; but humans, characteristically oblivious, keep making as much noise as possible, through efforts spearheaded by research organizations like the SETI Institute, which sends out radio signals into deep space in the event someone, anyone, else might hear them and make contact. Basically, one theory posits, by doing so, we’re alerting a species of apocalypse death machines to our presence. And now, NASA assembled a data sonification that bears an uncanny resemblance to the sound emanated from a (fictional) species of apocalypse death machines.
It’s fun to make the connection, although it is, admittedly, a far-fetched one. The real inspiration for the Reaper’s distinctive horn? Garbage, actually.