NASA has released a haunting audio clip of sound waves rippling out of a supermassive black hole, located 250 million light-years away.
The sound waves were actually previously identified by astronomers but have been made audible for the first time.
The black hole is at the center of the Perseus cluster of galaxies, and the acoustic waves coming from it have been transposed up 57 and 58 octaves so they’re audible to human hearing.
Scientists say the black hole sends out pressure waves that cause ripples in the hot gas, which can be translated into a note.
But the people at NASA say they shifted the note so we could hear it — amplified it and then mixed it with other data they have about black holes.
The result (below), released by NASA in May, is a sort of unearthly (obviously) howling that, if we’re honest, sounds not only spooky, but a little bit angry.
How NASA captured these sounds, the recordings of which were first released earlier this year, and what else we can “hear” in space.
The Perseus galaxy cluster was made famous almost 20 years ago, after sound waves were detected around its supermassive black hole.
It’s the first time these sound waves have been extracted and made audible.
In 2003, astronomers detected something truly astonishing: acoustic waves propagating through the copious amounts of gas surrounding the supermassive black hole at the centre of the Perseus galaxy cluster, which is now renowned for its eerie wails.
To be clear, though, the actual note is one humans can’t hear. It’s about 57 octaves below middle C.
Most of space is a vacuum that sound waves can’t move through, but galaxy clusters can release a lot of gas, which envelops the many galaxies inside of them, creating a medium for sound waves to travel through.
We wouldn’t be able to hear them at their current pitch. The waves include the lowest note in the Universe ever detected by humans – well below the limits of human hearing.
To create audio that is audible to humans, scientists do something known as sonification, which is the translation of this astronomical data into sound.
The sounds aren’t just a scientific curiosity, though. The tenuous gas and plasma that drifts between the galaxies in galaxy clusters – known as the intracluster medium – is denser and much, much hotter than the intergalactic medium outside galaxy clusters.
Sound waves propagating through the intracluster medium is one mechanism whereby the intracluster medium can be heated, as they transport energy through the plasma.
Because temperatures help regulate star formation, sound waves might therefore play a vital role in the evolution of galaxy clusters over long periods of time.
High Page rank:
That heat is what allows us to detect the sound waves, too. Because the intracluster medium is so hot, it glows brightly in X-rays. The Chandra X-ray Observatory allowed not only for the detection of the sound waves initially, but for the sonification project.