Spinetingling audio of a black hole goes viral, here’s why
<p dir="ltr">Audio that allows us to “hear a black hole” has gone viral online since it was shared by NASA, with listeners describing it as “creepy” and “ethereally beautiful”.</p>
<p dir="ltr">NASA first shared the audio taken from the black hole in the Perseus galaxy cluster in May, which it described as a remixed sonification of sound waves discovered in 2003, but a recent re-posting on Twitter has seen it gone viral.</p>
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<p dir="ltr">Here’s how it sounds:</p>
<blockquote class="twitter-tweet">
<p dir="ltr" lang="en">The misconception that there is no sound in space originates because most space is a ~vacuum, providing no way for sound waves to travel. A galaxy cluster has so much gas that we've picked up actual sound. Here it's amplified, and mixed with other data, to hear a black hole! <a href="https://t.co/RobcZs7F9e">pic.twitter.com/RobcZs7F9e</a></p>
<p>— NASA Exoplanets (@NASAExoplanets) <a href="https://twitter.com/NASAExoplanets/status/1561442514078314496?ref_src=twsrc%5Etfw">August 21, 2022</a></p></blockquote>
<p dir="ltr">Nearly twenty years ago, researchers at the Chandra X-Ray Observatory “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”.</p>
<p dir="ltr">But, said note was too low for humans to hear, being the equivalent of a B-flat 57 octaves below the middle C note on a piano, according to NASA.</p>
<p dir="ltr">To create something we could actually hear, scientists used a process called sonification, which is where astronomical data is translated into sound.</p>
<p dir="ltr">According to NASA, the creepy sound was created using sound waves extracted outwards from the centre of the Perseus cluster, with astronomers increasing the frequency by 57 and 58 octaves.</p>
<p dir="ltr">A radar-like scan around the image was also used to help us hear sound waves emitted in different directions.</p>
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<p dir="ltr">“Another way to put this is that they are being heard 144 quadrillion and 288 quadrillion times higher than their original frequency,” NASA said.</p>
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<p dir="ltr" lang="en">I was today years old when I found out that sound could travel into space.<br />In fact, NASA released sound waves received from a black hole!<br />Creepy 😲<br />Next, music please? 🎶<a href="https://t.co/myk0laXDV4">pic.twitter.com/myk0laXDV4</a></p>
<p>— Elie Habib (@elie_h) <a href="https://twitter.com/elie_h/status/1561773483092320256?ref_src=twsrc%5Etfw">August 22, 2022</a></p></blockquote>
<p dir="ltr">James Miller-Jones, a Professor of Astrophysics at Curtin University, told the <em><a href="https://www.abc.net.au/news/2022-08-24/nasa-audio-black-hole-sounds-viral-hear-space/101360094" target="_blank" rel="noopener">ABC</a></em> that the frequencies of these sound waves are impacted by gases in the Perseus cluster.</p>
<p dir="ltr">"Those sound waves are bumping into regions of dense gas, hotter gas, cooler gas, so they'll move in slightly different speeds in different directions," he explained.</p>
<p dir="ltr">"That means they don't have a perfect circular shape. So as they scan around the cluster … it's capturing slightly different pitches."</p>
<p dir="ltr">While this isn’t the first time the space agency has <a href="https://www.oversixty.com.au/entertainment/technology/hear-recordings-of-space-from-nasa-s-spacecraft" target="_blank" rel="noopener">shared sounds from space</a>, these sounds of the Perseus cluster differ in that they also use sound waves.</p>
<p dir="ltr">"This is the only one that I've seen that is really translating real sound waves into the sonification, and to me that's just a beautiful demonstration of what is going on. It's quite powerful," Professor Miller-Jones said.</p>
<p dir="ltr">"It tells us a lot about the cluster, and how energy is transported through it."</p>
<p dir="ltr">Kimberly Arcand, the principal investigator of the sonification project, described the sound as “a beautiful Hans Zimmer score with the moody level set at really high” when she first heard it in late 2021.</p>
<p dir="ltr">“It was such a wonderful representation of what existed in my mind,” she told <em><a href="https://www.washingtonpost.com/technology/2022/08/23/nasa-black-hole-sound/" target="_blank" rel="noopener">The Washington Post</a></em>, adding that it was a “tipping point” for the project in that it “really sparked people’s imagination”.</p>
<p dir="ltr">“The idea that there are these supermassive black holes sprinkled throughout the universe that are … belching out incredible songs is a very tantalising thing,” Arcand added.</p>
<p dir="ltr">The decision to release the “re-sonification” of the sound waves nearly two decades later came as part of NASA’s efforts to share complex scientific discoveries in plain English with its millions of social media followers.</p>
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<p dir="ltr">Though some experts have cautioned that NASA’s clip isn’t exactly what you’d hear in space, others argue that it would be realistic to believe that it would be what we’d hear if we had ears that were sensitive enough.</p>
<blockquote class="twitter-tweet">
<p dir="ltr" lang="en">I'm not religious, but I'm starting to think that those souls sent to Hell actually end up in a black hole.</p>
<p>Sound ON to be horrified <a href="https://t.co/75v74pkkhu">https://t.co/75v74pkkhu</a></p>
<p>— Paul Byrne (@ThePlanetaryGuy) <a href="https://twitter.com/ThePlanetaryGuy/status/1562065393581277185?ref_src=twsrc%5Etfw">August 23, 2022</a></p></blockquote>
<p dir="ltr">Even so, plenty of social media users have shared their thoughts on the sound, making comparisons to the Lord of the Rings and Silent Hill series or sharing it was an image of an intergalactic puppy overlaid.</p>
<p dir="ltr">“I can confirm that the black hole noise Nasa released is the sound of hell,” one user <a href="https://twitter.com/SlimeRegis/status/1562005777488945152" target="_blank" rel="noopener">wrote</a>.</p>
<p dir="ltr">“New genre just dropped: Cosmic Horror,” another <a href="https://twitter.com/cybxrart/status/1561690611983343616" target="_blank" rel="noopener">shared</a>.</p>
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<p dir="ltr"><em>Image: @NASAExoplanets (Twitter)</em></p>
