Moon Orbit Lab simulates N equal-mass moons orbiting a central planet with full N+1 body Newtonian gravity, integrated with Velocity Verlet — a symplectic method that keeps energy stable over long runs. Moons start at exactly the speed needed for circular orbits, accounting for moon↔moon gravity.
Sliders
· Moons — number of moons, uniformly spaced in circular orbits
3
· Mass ratio — moon/planet mass (log scale); try ≥ 0.1 for perturbations and chaotic scattering
0.001
· Speed — simulation speed multiplier
0.4×
· Trail — length as a fraction of one orbital period
0.20×
Buttons
· Reset (R) — restart with current settings, resets clock · Pause (Space) — freeze / unfreeze
· Reverse Time (V) — run the integrator backwards, exactly retracing the path
· Counter Rotate (C) — spin the camera at the initial orbital rate, keeping moons nearly stationary; great for spotting horseshoe orbits
· Load Background — replace the generated star field with your own image
Status
Elapsed time in orbital periods since last reset
T = 0.00 orbits
Energy conservation — large drift signals a chaotic or unstable orbit