Three-Body Problem: 3,915 Periodic Orbits Visualized
Original: An atlas of periodic solutions to the three-body problem
Why This Matters
Makes a hard open problem in physics accessible and browsable, potentially spurring new interest in celestial mechanics research.
A new interactive atlas at threebodyorbits.com maps 3,915 known periodic solutions to the three-body problem. Each orbit is animated live, spatially organized by visual similarity, and users can nudge orbits off-track, rate them, and pit them against each other in battles.
The three-body problem — predicting the motion of three mutually gravitating masses — has no general closed-form solution, but it does have thousands of special periodic orbits where the bodies return to their exact starting positions and velocities after one cycle. The site threebodyorbits.com collects all 3,915 currently known such orbits into a browsable atlas.
Orbits are arranged on a 2D map so that visually similar trajectories sit near each other, forming island clusters the site calls 'families.' Each family has its own page. Zoom out and the map resembles a star chart; zoom in and each orbit runs as a live animation. Individual orbit pages let users play one period at a time, perturb the initial conditions to watch stability break down, and rate orbits against each other in head-to-head 'battles' tracked on a leaderboard.
The project is built entirely in JavaScript for the interactive elements, with static fallbacks for the rest. It sits at the intersection of classical mechanics, numerical mathematics, and data visualization — making a notoriously abstract research area tangible and explorable for anyone with a browser.