Ever wondered what a black hole sounds like? No? Well NASA did and they recorded the acoustic waves coming from a black hole in the Perseus galaxy cluster and it sounds like a bone-chilling wind blowing in the night.
NASA’s recording of black hole
Located 250 million light years away, NASA had to transpose the audio up 57 and 58 octaves in order for them to be heard by the human ear.
This black hole has been associated with sound since 2003 when astronomers discovered that the pressure waves the black hole sent out were causing ripples in the Perseus cluster’s hot gas that could be translated into an audible note. However, this note is inaudible to humans as we cannot hear sound that is 57 octaves below middle C.
How to hear space
Being that no sound can travel in space, how are humans able to hear something so far away?
Through the technique of data sonification. This is when images are transformed into sound and the elements of an image, such as brightness and position are assigned a pitch and a volume.
The sonification process starts on the left side of the image and moves to the right and is a way of “listening” to images and data.
Scientists assign a louder volume to brighter light and light that is farther from the centre is given a higher pitch as a counter clockwise radar needle scans across the image.
It sounds confusing but here’s how to understand how it works:
Picture the hours on a clock. If you listen to the video of the spiral galaxy below and follow the radar needle, you’ll notice that the jingling melody is louder and higher pitched when the needle is over the furthest points of the spiral on the left at roughly 10 o’clock but once it reaches the empty black space at around 8 o’clock, it’s much quieter until it reaches the opposite tips on the right side of the spiral at 3 o’clock where it gets louder again.
Space can sound beautiful
Black hole round 2
Now try to listen to the sonification of the black hole again. You’ll notice that there’s far less variation in pitch and volume as the black hole has far less light than the spiral galaxy above. You can hear the same haunting wind of space in the spiral galaxy but also soothing melody coming from the spirals light.
The notion that there’s no sound in space is slightly inaccurate as there’s just no medium for sound waves to travel through. You can sort of compare it to song files on your phone which play through your phones speakers. If you didn’t have speakers, you wouldn’t hear those songs.
Bass drops in space
So that sick bass drop in that song you’re listening to on repeat? Well it’s nothing compared to what ever songs alien DJ’s play in clubs in the Perseus galaxy cluster because their bass drops must be so low in pitch you can’t even hear them.
It’s also likely that Meghan Trainor is hugely popular in that galaxy because with frequencies too low to be heard by the human ear, any life living out there most certainly is all about that bass.