Density of Neptune
We have
- Mass is 17 times the mass of the earth.
- Radius is 3.9 times the radius of the earth.
or approximately
- Mass is 16 times the mass of the earth.
- Radius is 4 times the radius of the earth.
The density is then 16/(43) = 16/64 = 1/4 times the density of the earth. More exactly, we get 0.29 times the density of the earth (5500 kg/m3) or 1600 kg/m3.
Davison E. Soper, Institute of Theoretical Science,
University of Oregon, Eugene OR 97403 USA
soper@bovine.uoregon.edu