NASA has translated into notes the pressure waves emitted by a black hole, normally inaudible to the human ear, to offer us a unique and rather chilling insight into its laments.
cosmic song
If no sound can theoretically propagate in the vacuum of space, certain regions of the cosmos, in particular located near black holes, are known to harbor large amounts of gas and dust. When these voracious monsters suck in surrounding matter, they create a medium for pressure waves to disperse, and it just so happens that those frequencies can be picked up and reworked to give us a sonic glimpse of their activity.
Since 2003, theChandra Observatory records sound waves around the supermassive black hole at the center of thehousewives of galaxies Perseus. Located about 250 million light-years from the Terrethe cosmic object emits pressure waves that cause ripples in the hot gas of the cluster surrounding it.
Because these low rumbles are well outside the range of human hearing (about 57 octaves below middle C), astronomers resynthesized the signal by boosting the frequencies 57 to 58 octaves above their actual pitch, thus proving to be 150 billion times more acute than at the origin.
A very different approach for the supermassive black hole of the galaxy M87
The NASA also sonified the supermassive black hole at the heart of the galaxy Messier 87 (or M87), first cosmic monster to be directly imaged in 2019, thanks to the collaboration Event Horizon Telescope.
Very different from that of Perseusthis second sound stage involved three types of light waves (emissions of X-rays captured by the observatory Chandraoptical light by space telescope Hubble and radio waves by theAtacama Large Millimeter Array), the frequencies of which have been assigned to the low, middle and high tones respectively.
According to the researchers, this distinct treatment explains why the sonification of the cosmic monster of the galaxy M87 turns out to be quite atmospheric, when that of the supermassive black hole of Perseus more reminiscent of the grunts of a hungry giant.