Black holes are some of the most extreme objects in the cosmos. These massive, extraordinarily dense objects have such strong gravity that they suck in anything which comes to close to them — even light. But that doesn’t mean that black holes are featureless. Although the black holes themselves are invisible, the clouds of dust and gas around them can get extremely hot and glow brightly, enabling telescopes to ‘see’ the black hole in detail.
It’s not just images that allow us to experience black holes though. NASA has produced a set of sonifications of black holes, turning these images into sounds as a different way to convey data collected by telescopes like the James Webb Space Telescope, Chandra X-ray Observatory, and Imaging X-Ray Polarimetry Explorer (IXPE).
The three sonifications are shared below, showing three different stages in the life of a black hole.
First up is WR 124, a type of star called a Wolf-Rayet which is a potential precursor to a black hole. As these old, massive stars come to the end of their lives, they start throwing off layers of gas into space, creating elaborate clouds around them. Eventually, when it has thrown off enough of its material, this star may collapse and become a new black hole.
In the sonification, the sounds start at the center where the core is, and moving out the X-day data is represented by harp sounds while data from James Webb is represented by bells. The other infrared data, from three different telescopes, is represented by strings.
The second sonification is of SS 433, a binary system consisting of a star like our sun and a much heavier partner which is thought to be either a black hole or a neutron star. The two objects orbit each other, creating changes in X-rays which are detectable by telescopes on Earth. Combining the X-ray data with infrared and radio, this sonification moves from right to left across the image. Points of light that are nearer the top of the image are represented by higher notes, while radio, infrared, and X-ray light is represented by low, medium, and high pitches. The stars in the background can be heard as water drop noises.
Finally, Centaurus A is a nearby and well-known galaxy, which is famous for being extremely bright and giving off strong radio waves. At its heart, this galaxy hosts an enormous supermassive black hole which is the star of this sonification. The black hole gives out a jet which is the source of the radio waves, and the sonification traces its effect in radar style, moving clockwise and representing X-ray data from Chandra as wind chimes, with X-ray data from IXPE in a continuous wind sound.