Context: Recently, NASA’s Chandra X-Ray Center (CXC) has gone a step further by unveiling a new ‘sonification’ project that transforms data from astronomical images into audio.
Key points

• Users can now ‘listen’ to images of the Galactic Centre, the remains of a supernova called Cassiopeia A, as well as the Pillars of Creation Nebula, which are all located in a region around 26,000 light years away from Earth.
• The data has been collected by NASA’s Chandra X-Ray Observatory, Hubble Space Telescope and Spitzer Space Telescope — each of which is represented by a different musical ‘instrument’.

What is ‘data sonification’?

• Data sonification refers to the use of sound values to represent real data. Simply put, it is the auditory version of data visualisation.
• In NASA’s recent Chandra project, for instance, data is represented using a number of musical notes.
• With this data sonification project, users can now experience different phenomena captured in astronomical images as an aural experience.
• The birth of a star, a cloud of dust or even a black hole can now be ‘heard’ as a high or low pitched sound.

About Sonification Project

• NASA’s sonification project is led by the Chandra X-ray Center in collaboration with NASA’s Universe of Learning Program (UoL), which aims to incorporate NASA science content into the learning environment for learners of all ages.
• Sonification projects like this allow audiences, including visually-impaired communities, to experience space through data.

How did NASA translate astronomical images into sound?

• NASA’s distant telescopes in space collect inherently digital data, in the form of ones and zeroes, before converting them into images.
• The images are essentially visual representations of light and radiation of different wavelengths in space, that can’t be seen by the human eye.
• The Chandra project has created a celestial concert of sorts by translating the same data into sound.
• Pitch and volume are used to denote the brightness and position of a celestial object or phenomenon. 

So far, the astronomers behind Project Chandra have released three examples made using data collected from some of the most distinct features in the sky — the Galactic Centre, Cassiopeia A, and Pillars of Creation Nebula.

• Galactic Centre: It is the rotational centre of the Milky Way galaxy. It comprises neutron, white dwarf stars, clouds of dust and gas, and a supermassive black hole called Sagittarius A*.
• Cassiopeia A: It is one of the most well-known remnants of a once-massive star that was destroyed by a supernova explosion around 325 years ago.
• The Pillars of Creation: It is located in the centre of the Eagle Nebula, which is also known as Messier 16.