Eight planets on their real orbits, each one a voice. They play faster near the sun, and alignments ring a bell. Uses mouse and keyboard. Runs in your browser; nothing is uploaded.
turns the sound on · space plays and pauses · arrow keys scrub a yearSpread: how much slower the outer planets play. Push: how much each planet speeds up near the sun. TIME above only moves the date and the alignments.
Drum Lab: each planet ticks at the tempo, slowed by its real period (spread) and sped up near the sun (push). With quantize on, a tick waits for the next 1/8 or 1/16 step, and odd steps are pushed late by the swing. Instruments follow the preset, change them per planet below.
Range ×1 uses Kepler's true intervals: Earth's speed barely changes, so it hovers within about a semitone, while Mercury's stretched orbit spans more than an octave. Raise the range to exaggerate the quieter planets.
Distance arc makes each planet climb the scale from its closest point to its farthest and fall back. The rhythm still follows Kepler's law.
Positions come from J2000 mean orbital elements projected onto the ecliptic. They are accurate to about a degree between 1800 and 2050 and drift further out. Distances are drawn on a compressed scale so the inner planets stay readable; speeds and notes use the real ones.