# Trajectory GUI

Trajectory GUI is a professional, open-source web application for designing rockets and planning, simulating, optimizing, and analyzing space missions. The canonical application is [https://space.lolisoft.eu/](https://space.lolisoft.eu/).

## Core capabilities

- Build staged launch vehicles from a reference catalog of engines and historical rockets.
- Define launch sites, target orbits, payloads, ascent guidance, and mission events.
- Simulate staged ascent with deterministic numerical integration, atmospheric drag, zonal gravity, staging, and closed-loop guidance.
- Plan orbital maneuvers, lunar transfers, and interplanetary transfers.
- Analyze reentry, landing predictions, Walker-delta constellations, and conjunctions.
- Optimize ascent programs with differential evolution and Nelder-Mead algorithms.
- Explore results on a 3D Earth, a 2D ground-track map, and live telemetry charts.
- Save mission and rocket documents with optimistic concurrency and version history.

## Technical architecture

The browser client is a React and Vite single-page application. Browser simulation runs in a Web Worker. A Fastify API provides persistence, authentication, catalog data, exports, batch simulation, and background optimizer jobs. PostgreSQL stores persisted documents. Shared Zod contracts validate transport data.

The platform-neutral orbital mechanics package is used by both browser workers and server jobs. It intentionally avoids DOM and Node-specific APIs so the same deterministic models run in each environment.

## Intended use and limitations

Trajectory GUI is intended for engineering exploration, education, and research. It is not certified flight software, and its results must be independently validated before safety-critical or operational use. Catalog values and simplified models can contain approximations; consult the mathematical-model documentation for assumptions.

The interactive application requires JavaScript and a modern browser with WebGL support. Most saved-document and server optimization features also require the deployed API and PostgreSQL database.

## Canonical resources

- Application: https://space.lolisoft.eu/
- Source: https://github.com/jomardyan/Trajectory-GUI
- Architecture: https://github.com/jomardyan/Trajectory-GUI/blob/main/docs/01-architecture.md
- Mathematical models: https://github.com/jomardyan/Trajectory-GUI/blob/main/docs/09-mathematical-models.md
- API design: https://github.com/jomardyan/Trajectory-GUI/blob/main/docs/05-api-design.md
- License: https://github.com/jomardyan/Trajectory-GUI/blob/main/LICENSE