Which planet wins the moon race? · 1900–2025

JPL Solar System Dynamics · current satellite discovery catalogue, retrieved 18 Oct 2026. Retrospective reconstruction: each currently catalogued moon is counted once at its earliest listed discovery year. Not a history of confirmations or what was officially known at each date. The 1900 baseline includes earlier discoveries: Jupiter 5, Saturn 9, Uranus 4, Neptune 1. In 2025: 115, 293, 29, 16 respectively. Four selected giant planets, 504 observations (126 years × 4). Counts are already cumulative; native cumulative mode stays off. No missing values filled with zero; animation between annual points is visual interpolation. Images: Jupiter and Neptune NASA/JPL; Saturn NASA/JPL/USGS; Uranus NASA/JPL-Caltech. No NASA/JPL endorsement. Discovery references, image credits and reuse policy in source notes.

JPL satellite discovery catalogue with linked discovery references. NASA/JPL imagery: acknowledge the exact image credits and follow the JPL Image Use Policy; no endorsement implied.