What you are about to hear is not the performance of an orchestra, it is the movement of a recently discovered star system – the sound of Trappist-1. The researchers from Canadian Institute for Theoretical Astrophysics translated the movements of the planets in the Trappist 1 to animation and sound. The resulting song is complex but surprisingly stable.
Researchers depict the relationship between the TRAPPIST planets in animation and sound. They used a numerical simulation of Trappist-1 to play a piano note every time a planet passes in front of the star and a drum every time a faster inner planet overtakes its outer neighbor.
The result is this lovely tune, composed by the cosmos itself, which would make a great first track on a playlist curated for any future interstellar missions to Trappist-1.
In this musical model, each planet is assigned a pitch that is 212 million times its orbital frequency, to put it in the human hearing range. The motion of the planets is also sped up by 212 million so it doesn’t take 18.76 days (the length of the outermost planet’s year) to complete one bar of the song.
Most planetary systems are like bands of amateur musicians playing their parts at different speeds. Trappist-1 is different. It’s a super-group with all seven members synchronizing their parts in nearly perfect time, says animation creator Matt Russo.
Trappist-1 makes beautiful music because each planet happens to line up in a “resonant chain.” Two orbits of the outermost planet have an equal period to three orbits of the sixth planet, four orbits of the fifth planet, six orbits of the fourth planet, nine orbits of the third planet, 15 orbits of the second planet, and 24 orbits of the innermost world, Trappist-1b. There is a rhythmic repetition that provides long-term stability of the system. With any other system, it will be hard to get something like this. That’s what is so special about Trappist-1, says Russo.