Here's what the TRAPPIST-1 system sounds like as a space symphony

The universe is a pretty grand place, more than deserving of its own symphonic score. So why not let it compose its own?

That’s what a group of three talented Canadian astrophysicists and musicians have helped make possible, as a tribute to NASA’s recent discovery of seven Earth-sized exoplanets in the TRAPPIST-1 system, three of which orbit in the habitable zone.

“We’ve created a code that directly translates the motions of planetary systems into music,” Matt Russo, a post doc at the Canadian Institute for Theoretical Astrophysics, told Digital Trends. “Although the deep connections between music and astronomical systems were first explored centuries ago by Johannes Kepler, the recent discovery of TRAPPIST-1 inspired us to try it out with 21st century technology. TRAPPIST-1 has the longest chain of resonances ever found, in which each planet’s period forms a low integer ratio with the periods of its neighbors. For every two orbits of the outer planet TRAPPIST-1h, the next one orbits three times; the next one after that four, then six, then nine, then 15, then 24. Not only does this mean that their orbits follow a steady repeating pattern but when the orbital frequencies are scaled into the human hearing range, the note corresponding to each planet form consonant notes in a chord which is surprisingly beautiful and eerily human.”

As you can see in the video at the top of this page, the so-called System Sounds plays a single piano note for every time a planet passes in front of its star, and plays a drum for every time a faster inner planet overtakes its neighbor. Based on this simple premise, however, the sheer number of parts in the TRAPPIST-1 system produces some incredibly dense music. Combined with a bit of a human helping hand in scaling up the orbital frequencies to make the period ratios whole numbers (“Over the past few billion years, the system has de-tuned slightly mainly due to tidal forces,” Russo said) the results spell out the inner workings of the newfound system.

Don’t expect it to work quite so well with other systems, though. “TRAPPIST-1 was really something special, and I’m not sure if we’ll ever find a system that’s as musical as that but I know many teams of observers are trying,” he explained. “There are several teams focusing on observing small planets around cool red dwarfs like TRAPPIST-1 and I can’t wait to see what they find. We’ll definitely translate the solar system, but will have to be a little more creative since the range of frequencies can’t fit into the human hearing range the way the planets of TRAPPIST-1 did.”

Russo’s collaborators on System Sounds include musician Andrew Santaguida and Dan Tamayo, a postdoctoral researcher at the University of Toronto’s Center for Planetary Sciences and the Canadian Institute for Theoretical Astrophysics.