SkyEngine.SGP4(near-Earth), verified against Vallado's satellite 00005 to 10 m in position and 1e-5 km/s in velocity.SkyEngine.passes(of:from:hours:observer:): rise, peak, set, directions, visibility (sunlit and dark sky).- Worker: CelesTrak GP every 2 h (cron
7 */2 * * *), sequential fetches, stop on first non-200;GET /v1/satellites. - Today sheet: next passes, with Visible tags.
Not cross-checked against an external pass predictor (e.g. Heavens-Above).