Orbital mechanics · ρ = M / (4⁄3 π r³)
Mean Density
The average density of a body from its mass and radius — a clue to its composition. Earth's ~5510 kg/m³ points to a rock-and-iron world; the giant planets are far less dense.
Mean density5513.4kg/m³
Formula: ρ = M / (4⁄3 π r³)
Worked example
With the default inputs, mean density evaluates to 5513.4 kg/m³ — Earth → ~5510 kg/m³. The validator recomputes this against the known value on every build, so the formula is checked, not asserted.
Highlights
- ›Earth: ~5510 kg/m³
The physics behind it
Knowledge connections
- Associated withUniversal Gravitation
Sources
The primary and reference sources this topic draws on.
- NASANational Aeronautics and Space Administration
Mission data, planetary science, space telescopes, and public-domain imagery.
Most NASA-produced imagery is in the public domain; individual items are checked for usage terms before publication.