Wednesday, August 24, 2022

Black Hole Moaning

The Perseus galaxy has a lot of gas in its space, and the sound of the black hole at the center of the galaxy is a bit unnerving. These sound waves were detected by NASA's Chandra X-ray Observatory, but they can't be heard in their raw form, which is 57 octaves below middle C. So NASA has "translated" the sound, much as they translate colors of far away images that are detected in parts of the light spectrum we cannot see with human eyes. This is what we call sonification. Read more about the project at NASA. (Thanks, WTM!)


Anonymous said...

> A galaxy cluster has so much gas that we've picked up actual sound.

What happens when physicists shoot a bunch of cabbage into a black hole.

Anonymous said...

Reminds me of 2001 Space Odyssey.

Lilylou said...

It's almost musical!

Anonymous said...

Middle C is 256 Hz ... so a vibration 256 times a second
1 octave below Middle C is 128 Hz ...
8 octaves below Middle C is 1 Hz ... a vibration once a second
57 octaves below Middle C is 0.000000000000001776 Hz ... a vibration once every 17 million years.

How are we measuring a soundwave that only vibrates every 17 million years??
Honestly that's more astounding to me than the "sound" this produces - the fact that we can actually measure the frequency of something that we have only the tiniest snapshot of.

Andy said...

> How are we measuring a soundwave that only vibrates every 17 million years??

I imagine they're observing waves of density in the gas and translating that to sound. In other words, middle C has waves of air density spaced by 1.3 m so the gas density waves of the Perseus galaxy must be separated by 74 m.

It sounds like the middle section of Pink Floyd's Echoes, to me.