Tour: A Tour of Jingle, Pluck, and Hum: Sounds from Space

Space is mostly quiet. Data collected by telescopes are most often turned into silent charts, plots, and images. A "sonification" project led by NASA's Chandra X-ray Observatory and the Universe of Learning transforms otherwise inaudible data from some of the world's most powerful telescopes into sound. This effort makes it possible to experience data from cosmic sources with a different sense: hearing.

The latest installment of this sonification project features a region where stars are forming (Westerlund 2), the debris field left behind by an exploded star (Tycho's supernova remnant), and the region around arguably the most famous black hole (Messier 87*). Each sonification has its own technique to translate the astronomical data into sounds that humans can hear.

Westerlund 2 is a cluster of young stars — about one to two million years old — located about 20,000 light years from Earth. In the sonified version of these data from Chandra and Hubble, the pitch of the notes indicates the vertical position of the sources in the image with the higher pitches towards the top of the image. Meanwhile, the volume corresponds to the brightness of each source. The Hubble data are played by strings, where the stars are plucked strings and the clouds are strummed notes. Chandra's X-ray data are represented by bells and the more diffuse X-ray light are played by more sustained tones.

Beginning in the center, the sonification of the Tycho supernova remnant expands outward in a circle. The image contains X-ray data from Chandra where the various colors represent small bands of frequency that are associated with different elements that are moving both toward and away from Earth. For example, red shows iron, green is silicon, and blue represents sulfur. The sonification aligns with those colors as the redder light produces the lowest notes and blue and violet create the higher pitched notes. White corresponds to the full range of frequencies of light observable by Chandra, which is strongest toward the edge of the remnant.

The giant black hole in Messier 87 (M87 for short) and its surroundings have been studied for many years and by a range of telescopes including Chandra and the Very Large Array. These data show that the black hole in M87 is sending out massive jets of energetic particles that interact with vast clouds of hot gas that surround it. To translate the X-rays and radio waves into sound, the image is scanned beginning at the 3 o'clock position and sweeping to the right like a radar. The brighter data, the louder and higher pitched the sounds are. The radio data are lower pitched than the X-rays. The point-like sources in X-ray light, most of which represent stars in orbit around a black hole or neutron star, are played a short, plucked sounds.

Listen for more from the sonification project in the future.