What do black hole sound like?

Since 2003, the black hole at the center of the Perseus galaxy cluster has been associated with sound.

Indeed, astronomers discovered that the pressure waves emitted by the black hole caused ripples in the hot gas of the cluster that could be translated into a note - a note that humans not hearing about 57 octaves in below median.

This new sonification is published this year for NASA's black hole study. In some respects, this sonification is unlike any done before, as it revisits actual sound waves in data from NASA's Chandra X-ray Observatory.

The popular misconception that there is no sound in space stems from the fact that most of space is essentially a void, providing no sound for sound waves to spread.
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A cluster of galaxies, on the other hand, contains masses of gas that shroud the hundreds or even thousands of galaxies it contains, providing a means for the waves to travel. In this new sonification of Perseus, the sound waves identified by astronomers have been extracted and rendered for the first time.

The sound waves were extracted in radial directions, that is, outwards from the center. The signals were then resynthesized into the range of human hearing by scaling them to about 57 and 58 octaves above their pitch.
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Another way of saying this is that they are 144 quadrillion and 288 quadrillion times higher than their original frequency. Radar-like scanning around the image lets you hear waves radiating from different directions. In the visual image of this data, blue and purple both show x-ray data by Chandra.

aIn addition to the cluster of Perseus galaxies, news of another famous black hole is in the works. Studied by scientists for decades, Messier hole 87, or M87, achieved scientific celebrity status after the first Event Telescope project was published in 2019.
This new sonification does not present the EHT data, rather examines the data from other telescopes that observed at much larger scales at around the same time.The image in visual form contains three panels which are, top to bottom, Chandra's X-rays, NASA's Hubble Space Telescope optics, and radio waves from the Atacama Large Millimeter Array in Chile .

The brightest region to the left of the image is where the black hole is, and the top right is a black hole-produced jet. The jet is produced by matter falling from the black hole. The sonication scans the image at three levels from left to right, each wavelength corresponding to a different range of audible tones.

​The radio waves are mapped to the highest tones, the optical data to the medium tones and the rays detected by Chandra to the highest tones. The brightest part of the image corresponds to the strongest part of sonification, where the 6.5 billion mass black hole that the EHT imaged is located .

More sonifications of astronomical data, as well as supplements on the process, can be found on the web "A Universe of Sound": https://chandra.si.edu/sound/ These Sonifications were led by the Chandra X-ray Center and included as part of NASA's Universe of Learning program additional support from NASA's Hubble Space Telescope/Goddard Space Flight.
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The collaboration was led by scientist Kimberly Arcand, astrophysicist Matt Russo and musician Andrew. NASA's Marshall Space Flight Center operates the Chandra program. Smithsonian Astrophysical's X Chandra Ray Center controls science from Cambridge, Massachusetts, and operations from Burlington, Massachusetts.