Solar System String Sequencer (SSSS) is a playful music instrument made to explore the musicality of our solar system through the sonification of its planets and their orbits.

How to play

• Play with a keyboard and mouse (fullscreen recommended).
• Click and drag to build strings between planets and spin the camera around.
• Drag the sliders to change speed of time and the speed of the wave within the strings.
• Click in the empty space to toggle top-down building-friendly view and planet-orbiting view.
• Use the mouse scroll wheel to zoom in and out.
• Click each planet's button on the top to select it and focus the camera on it.
• Click on any action at the bottom of the screen to perform said action.
• Alternatively and moreover, press any key displayed between brackets [] on your keyboard to trigger the described action, ie: [T] key toggles the timeline view.
• Enjoy some solar-system music

About the project

Personal background

These last couple of years I've happened to cross path and talk with with several space-related people and projects, which have led me to ask myself some questions and eventually led to the development of this project.

Back in 2023 I visited my astrophysicist friend Edgar Molina, who was working with and around the Institute of Astrophysics of the Canary Islands in Tenerife. We passed by the solar Teide Observatory and climbed all the way up to Teide's peak.
One clear night in la Gomera when some of us were wondering about which shinning lights in the sky were planets, Edgar shared with us a pretty remarkable insight:
Because most planets are orbiting the sun at pretty much the same orbital plane, when we look at the night sky, if we know the trajectory of the sun or the moon across the sky, we can follow the same imaginary line to find any and all the other planets of the solar system, if they are visible that night.

This is obvious if you ever think about it, but for me it was a pretty memorable conclusion!

Back in Taiwan, I had the chance to visit Taiwan Space Agency (TASA)'s research institute in Hsinchu, because another friend happens to work there, and saw with my own eyes a Formosat-8 imaging satellite (from the distance) who was getting ready to be lifted to orbit.
Nearby we also visited the 光譜丘 Spectral Pulse Studio Art Lab for an audio-visual performance. The lab involves several artists who are astrophysicists, and during the performance they included visual and audio renderings of supernova simulations and other high-energy astronomical events.

Since I've always liked physics and I love music, one thing let to another and soon enough I was left with a question..

Research question

If we were able to build hypothetical musical strings between celestial bodies, and let these bodies pluck these strings when their orbiting paths cross said strings (when 3 bodies align), how would the resulting music (frequencies and rhythm) sound like?

About the simulation

In order to simulate this instrument I took some liberties to simplify the simulation and calculations:

1. For UX purposes, the sizes of the planets and the sun are only loosely related to their relative sizes.
2. For the orbits of the planets I'm using NASA's Keplerian elements.
3. Time always starts at the browser's local time and moves forward.
4. Strings don't break and are able transmit the wave within it at the speed of light c. 
5. Through the pass of time and change of length of the strings (change of distances between planets), strings are able to maintain a constant speed of the wave within it.
6. String plucking happens in a 2-dimensional simplified coordinate system: 3-dimensional coordinates are projected into the invariable plane of the solar system. Celestial bodies "pluck" strings when their projected center passes over a projected string.
7. We hear strings plucks without delay when they happen regardless of our point of view.

Example frequency calculation

At the start of this game, with the speed of the wave through the strings being c, and time passing at 12 days per second, let's consider a string between Earth (3) and the sun (0): a string approximately 149597870.7 Km (1 AU) long.

From Mersenne's laws, we know that the fundamental frequency f of a string of length L, when the velocity v of the wave in the string is known is:

Thus the fundamental frequency of such string would be f = c / 2AU which is roughly 1.002 mHz. If we take in consideration that our simulation is running at 12 days per second, this translates to a simulation-time frequency of 1038.86 Hz, roughly translating to a C6 note in the western musical scale.

Future updates

• Add the ability to output midi through the Web MIDI API
• Add the ability to connect to another program through OSC protocol

Credits

• Idea, design and code: Ferran Bertomeu Castells
• Made using Three.js and Tone.js
• Title font: NEVERA by Almeera Studio
• Planet textures: recovered from an old university project of which unfortunately I have no record of their sources. Probably most of them from NASA.

This project was originally made for Operator Digitalfest 2026, and then polished a bit more for an itch release.