Moons — physical parameters & orbits:
NASA/JPL Solar System Dynamics ↗
Asteroids & comets:
NASA/JPL Small-Body Database ↗
Earth defence — hazardous asteroids,
Sentry impact risk ↗,
close approaches ↗ &
fireballs ↗: NASA/JPL CNEOS
Satellites:
CelesTrak GP catalogue ↗ ·
Impact craters:
Earth Impact Database / Wikipedia ↗
Planet positions:
JPL Approximate Ephemeris ↗ ·
Surface imagery:
Solar System Scope (CC BY 4.0) ↗
Moon & dwarf-planet mosaics: NASA/JPL/USGS — Voyager, Galileo, Cassini, New Horizons & Dawn missions, via
Stellarium ↗
Planetary data:
NASA NSSDCA Planetary Fact Sheets ↗