PPolySim OS

Lagrange Points

Five special points where a small object can ride along with two orbiting bodies. JWST parks at Sun-Earth L2; Jupiter's Trojans swarm L4 and L5.

Lagrange PointsLive

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In a two-body system, five points let a small object stay fixed in the rotating frame. L1-L3 sit on the line through the two masses (unstable); L4 and L5 lead and trail the secondary by 60° and are stable for μ below 0.0385 — where Jupiter's Trojan asteroids live. JWST orbits the Sun-Earth L2.

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Data Inspector

μ = m₂/(m₁+m₂)0.150
L4/L5 stable?no
Points5

Governing equation

Reading this result: At μ=0.150 the masses are too comparable: even L4 and L5 turn unstable, so every Lagrange point here needs active station-keeping to hold a spacecraft in place.

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How it works

In the restricted three-body problem, the combined gravity and rotation create an effective potential with five equilibrium points. L1-L3 lie on the line joining the two masses and are unstable; the triangular points L4 and L5 are stable when the mass ratio is below 0.0385. Toggle the potential to see the contours that define them.

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Frequently asked questions

Is this Lagrange points three body tool really free?▾
Yes. Lagrange Points runs entirely in your browser using your device's own compute, so local use is free forever. You only pay Compute Tokens if you scale a job to the cloud.
Do I need to install anything?▾
No. Everything runs client-side in a modern browser — no downloads, no license, no account required to start.
Can I save or share my simulation?▾
Create a free account to save projects, and use a shareable embed or minted DOI to publish a live, interactive version anywhere.
How accurate are the results?▾
The solver uses established numerical methods, but results are for research and educational purposes and should be validated against experiment or professional review before you rely on them.