N-Body Gravity Simulator
Two bodies orbit predictably; three or more generally do not. This simulator lets you place any number of masses, give them initial velocities and watch the gravitational interactions play out, including slingshots, captures and ejections.
How to use this simulation
- Add bodies and set their masses and starting velocities
- Adjust the simulation speed
- Trace orbital paths over time
What to look for
- Two-body systems settle into stable ellipses
- Adding a third body can destabilise the whole arrangement
- Close encounters fling bodies away at high speed as they trade energy
The physics behind it
Every pair of masses attracts with F = Gm₁m₂/r², and the net force on each body is the vector sum of all the others. Two-body orbits are exact conic sections, but from three bodies onwards there is no general closed-form solution — the motion has to be computed step by step and is often chaotic.