Special technology turns NASA data into a melody from the center of the Milky Way
Composer Sophie Kastner has turned data from the Milky Way's galactic center into music. Her piece Where Parallel Lines Converge takes inspiration from the central region of our galaxy.
This image was captured at various wavelengths of light – X-ray, infrared and optical – by the Chandra, Hubble and Spitzer space telescopes. As a result, the composition can be heard to reflect the sound reflections of many objects and structures found in the region, such as gas bubbles, stellar cores, dust lanes and stellar nurseries.
Instead of trying to capture the entire audio experience of a complex image, Kastner decided to focus on three key elements. The first is a binary star system detected in X-rays, indicated by the bright blue orb on the left of the image. The second is a group of arcuate structures. And the third – the most majestic of all – is the supermassive black hole Sagittarius A*, hidden in the heart of our Milky Way.
“My goal was to draw the listener's attention to small events within the entire data set,” Kastner shared about the composition's reception.
However, the question arises of how the data obtained from telescopes can be converted into sound waves, since there is no air in space for sound to travel. Sound vibrations are transmitted through atoms and molecules in the air on Earth. However, in space, where there is a vacuum, there are no atoms.
To overcome this obstacle and turn space data into sound signals, NASA's Center for X-ray Astrophysics has launched a sound extraction project. Scientists are developing methods to convert data into sound so that people can hear and perceive the results of space observations through their ears. Through this project, interpretations of sound waves have been obtained for various cosmic phenomena such as supernovae, galactic groups and nebulae.
Music associated with space images is an interpretation of data rather than a direct transmission of sounds that exist in space. It is a work based on scientific information about space objects, which represents a new way of perception that allows people to interact with the night sky through music.
“The cluster contains sufficient amounts of gas spanning hundreds or even thousands of galaxies, providing an environment for sound vibrations to propagate,” the NASA research team reports.
So, last year, scientists were able to determine that the black hole in the Perseus cluster is surrounded by gas, which creates the necessary pressure to transmit sound waves that can be recorded by scientific instruments.
These vibrations were turned into actual musical notes, but they turned out to have too low a frequency – 57 octaves below middle C. This is too low for human hearing. So the team synthesized the signals to a frequency that could be heard by human ears, increasing their frequency in pairs by 57 and 58 octaves up (that's 144 quadrillion and 288 quadrillion times their original frequency). The resulting sounds were an accurate reflection of the expected manifestations of a black hole.