Solar-Wanderer is a browser-based, real-time 3D solar system explorer that renders the solar system at 1:1 scale using authentic NASA JPL ephemerides. The application runs entirely client-side with no backend, built on Three.js and WebGL2. It supports seamless transitions from orbital view to atmospheric entry, surface walking, and underwater exploration across dozens of celestial bodies. The architecture is a monolithic single-page application with a clear separation between an astrodynamics layer (ephemeris computation, VSOP87, Kepler solvers, rotation models), a rendering/engine layer (floating-origin, camera feel, quality management, audio, WebXR), a scene layer (atmosphere, terrain, rings, procedural textures, starfield, spacecraft), and a UI layer (HUD, labels, tours, bookmarks, i18n, TTS). A significant portion of the codebase is dedicated to data acquisition and verification: over 150 Node.js scripts fetch, process, and validate ephemeris data from JPL Horizons, DEM tiles from NASA PDS, texture maps from USGS, and star catalogs from BSC5. The project emphasizes scientific accuracy and engineering rigor, with detailed audit reports, automated visual regression testing, and a structured quality tier system that adapts to device GPU capability.