Earth's average density is approximately 5.513 g/cm³ (or 5513 kg/m³). This average density is a crucial characteristic, revealing insights into the planet's internal structure and composition.
Understanding Earth's Density
The density of Earth isn't uniform; it varies significantly from the crust to the core. The Earth's core, primarily composed of iron and nickel, is considerably denser than the less dense mantle and crust which are mostly composed of silicate rocks. This variation in density is a key factor contributing to the planet's overall average.
Several sources confirm this average density:
- NASA's Earth Fact Sheet: Reports Earth's density as 5513 kg/m³. https://nssdc.gsfc.nasa.gov/planetary/factsheet/earthfact.html
- Universe Today: States the Earth's density as 5.513 g/cm³. https://www.universetoday.com/26771/density-of-the-earth/
- UCL's Seismology Group: Gives the average density as 5.5 g/cm³. https://www.ucl.ac.uk/seismin/explore/Earth.html
- Wikipedia (Earth mass): Provides an average density calculation based on Earth's mass, resulting in a similar value. https://en.wikipedia.org/wiki/Earth_mass
The higher average density (5.5 g/cm³) compared to the density of surface rocks (around 2.5-2.6 g/cm³) indicates a significantly denser interior. This is consistent with the presence of a dense iron core.
Practical Implications
Understanding Earth's density is crucial for various fields:
- Geophysics: Modeling the Earth's interior structure and dynamics.
- Planetary Science: Comparing Earth's properties with other planets.
- Geology: Interpreting geological formations and processes.
