Show HN: Real-time Solar System with 526k asteroids and all tracked satellites
A browser-based, real-time 3D visualization of the Solar System shows planets, 526,000 asteroids, and all tracked Earth-orbiting satellites at true spatial scale (with marker sizes exaggerated), impressing many with its performance and visual clarity. Commenters highlight how the tool reveals the density of man-made debris and Starlink satellites, the structure of geostationary and Trojan asteroid regions, and the vast emptiness between objects despite the apparent clutter. Technical details such as WebGL2 rendering, daily-updated orbital data from JPL and CelesTrak, and UX tweaks like time controls and search are also explored, along with comparisons to older tools like Celestia.
Project overview & data sources
- Browser-based, real-scale solar system visualization with current positions of planets, ~526k asteroids, comets, and tracked Earth satellites.
- Uses CelesTrak TLEs with SGP4, JPL SBDB for small bodies, and JPL Horizons state vectors for spacecraft; data updated daily.
- Satellites are propagated from current TLEs backward in time; beyond ~90 days past is marked as “estimate.”
Scale, realism & interpretability
- Distances are to scale; object markers (planets, satellites, debris) are not. This is clarified after confusion about visible satellite sizes and “space is crowded” implications.
- Some users note that Earth’s geostationary belt appears as a ring only because marker dots are huge versus real objects.
- Visualization highlights structures like Jupiter’s Trojan swarms, Lagrange-point halo orbits (e.g., JWST), and flyby trajectories.
Performance & implementation
- Rendering is WebGL2 with no external engine. Orbit propagation for asteroids is done fully on the GPU; vertex shaders solve Kepler’s equation per frame.
- No distance-based culling is used, yet performance is reported as smooth even with hundreds of thousands of objects.
UX, features & fixes
- Requests: faster zoom (especially on mobile), easier centering on planets, better panel management, VR version, search enhancements, “Now” button discoverability, pause/spacebar controls.
- Implemented changes during the thread include: clarified scale wording, bugfixes for debris orbits at high speed, ESC to deselect, spacebar pause, a white Sun texture, search for specific asteroids and “interstellar” objects, and an “endless ambient” mode with generated music and time-lapse flybys.
Satellites, debris & Kessler concerns
- Discussion notes how visually dominant Starlink is; one comment states that a majority of active maneuverable satellites are from that constellation.
- One commenter argues current trends could severely impact night-sky visibility; another counters that low-orbit constellations deorbit quickly and that Kessler risk is higher at 700–1,000 km than below 500 km.
Asteroids, surveys & safety
- Many express surprise at the number of tracked near-Earth asteroids.
- Others reference ongoing and planned survey missions and impact-mitigation experiments, noting that planetary-defense work is active and improving.