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.