How science hears the creepy sound of a black hole

The NASA Exoplanets account, which publishes scientific information about the universe beyond the Solar System of the US Space Agency (NASA), has just posted an explanation of how humans "hear" the sound of black holes.

In May, NASA released a 35-second audio recording of the black hole at the center of a massive galaxy cluster in the constellation Perseus, 240 million light-years from Earth.

This cosmic object emits a strange low growl sound, which sounds like a door creaking every time it opens and closes.

However, this notion has been broken. Recently, NASA's Chandra X-ray Observatory recorded the sound waves of a black hole in the form of astronomical data, then converted into sounds that humans can hear.

In fact, this data was obtained by the Chandra X-ray Observatory 20 years ago. They are pressure waves (sound waves) spanning 30,000 light-years, covering the 11 million light-year wide Perseus galaxy cluster. This is also the medium for sound waves to pass through.

'The first 10 years I worked, I only focused on images in the galaxy. But then, I gradually realized that my work is not helping people who are not experts in space or have vision problems," NASA scientist Kimberly Arcand told NPR.

Thus, she converted the pressure wave from a black hole into sound that can be heard by the human ear. This process is called "sounding" the data from the black hole. In addition, Arcand also recorded the sounds of many other objects in the universe. Each material from an interstellar cloud or star has a different sound.

According to NPR, by 'sounding' the data, astronomers have synthesized sound waves in the galaxy cluster. These sounds are located 57-58 octaves away from the middle C (C4). Therefore, in order for the human ear to hear these ripples, the Chandra Observatory raised the tone by 57-58 octaves, increasing the frequency by 4 billion times compared to the original.

The Chandra X-ray observatory has been collecting black hole sonar data since 2003.

The recording and publication of the sound of a black hole in the constellation Perseus is one of the activities of Black Hole Week 2022.

NASA also announced the sound was captured during the transition from light data in the energy beam fired from the black hole of the galaxy M87, 53.5 million light-years from Earth.

Another cosmic 'sounding' project has been carried out by Erin Kara, an astrophysicist with the Massachusetts Institute of Technology. Her team used signals from X-ray bursts to map the environment around black holes, similar to how bats use sound to catch mosquitoes.