Trailer V1.1 : Watch here

Trailer V1 : Watch here

Stellar System is a C++ plugin for Unreal Engine 5 that lets you build complete, physically accurate orbital systems — from a single moon orbiting a planet to fully procedurally generated star systems with suns, planets, and satellites.

Every orbit is defined by the six classical Keplerian elements: semi-major axis, eccentricity, inclination, longitude of the ascending node, argument of periapsis, and initial angle. This means you can place any orbit exactly where you want it in 3D space, with elliptical paths, orbital plane tilts, and periapsis orientation all independently controllable from the Details Panel.

What's included

- AOrbitingActor : drop it in your level, assign an orbit center, and it moves. Comes with mesh, material, and planet data built in.

- UOrbitActorComponent : attach orbital motion to any existing actor without changing its class.

- Procedural Generator : place one actor and get a full star system at BeginPlay: suns, planets classified by temperature (Lava, Rocky, Desert, Ocean, Ice, Gas Giants), and satellites, all with collision-safe non-overlapping orbits.

- Multiplayer support : positions are computed deterministically from server time on every client. No position replication, no drift, no jitter.

- Blueprint utility nodes : compute orbital period, speed factor relative to mean motion, distance to focus, and orbit speed from mass (Kepler's Third Law).

- Axial rotation : configurable spin speed and axial tilt per body (Earth, Uranus-style retrograde, anything in between).

Do I need C++ to use it?

No. Every parameter and utility function is exposed to Blueprints. You can build a complete solar system without writing a single line of code.

Support

Join the Discord for questions and bug reports.

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