From Gustav Holst's orchestral suite "The Planets" to any John Williams composition for "Star Wars" to the Steve Miller Band's "Space Cowboy," space has inspired the musically inclined for centuries.
But space can also create music, and in honor of the Mars rover Opportunity seeing its 5,000th Martian sunrise, scientists created a tune not just inspired by the sunrise but by using data from the photograph of the sunrise itself.
The video above was created by Domenico Vicinanza of Anglia Ruskin University and Genevieve Williams from the University of Exeter. The tones you hear were developed by scanning the image from left to right, pixel by pixel, according to a statement released by Anglia Ruskin University. Pitches and melodies were then assigned to things like brightness, terrain elevation and color.
For instance, the quieter portions of the piece are a result of the dark background of the image while the higher-pitched sounds are related to the sun's brightness.
To create this music of the spheres, Vicinanza and Williams used a process called data sonification. When we typically want to represent data, we use words to explain or charts and graphs to illustrate. Some scientists and researchers, however, are looking for alternative ways to make data consumable, and data sonification does that. So instead of lines on a chart, we get pitches, tones and melodies.
At first, data presented in this way can result in something abstract, as if someone made a not-so-great remix of a Philip Glass or Terry Riley composition. And that's normal, according to Jack Jamieson, a Ph.D. student at the University of Toronto. Writing for Open Shelf, Jamieson explains that many of us are simply "not used to decoding this sort of abstract information from non-speech sound, and the process takes some getting used to."
But the process can be a helpful one, as Jamieson points out. Sonification makes the visible audible, which is important for people with visual impairments. The technique has been used to help such people even make their way around rooms. Jamieson also highlights how this process can allow people to monitor network activity in the background, with tones and notes used to indicate hacking or abuse in the otherwise normal flow of data. People can focus on visual tasks while still keeping an ear on other things.
"Image sonification is a really flexible technique to explore science and it can be used in several domains," Vicinanza says in the statement, "from studying certain characteristics of planet surfaces and atmospheres, to analyzing weather changes or detecting volcanic eruptions."
We told you what the tones in the Martian sunrise photo were translated from, and you've seen the photo. Try listening to the piece again, but this time don't look at the photo. Close your eyes or switch to another tab in your browser. Now think about how we use tones to represent moods in music and how that carries over to the piece Vicinanza and Williams created. Or, have a friend or co-worker listen to the piece, ask what they thought, and then have them listen to it again, but this time with the image visible and with an explanation of what the tones and pitches represent.
It's a whole new way of experiencing the universe.