Earth Ground Probe Results   Surface Materials - Basaltic rock, Granite rock, and altered material Mean Density - 5520  kg/m^3 Surface Density - 1.217  kg/m^3 Surface Gravity - 9.81  m/s^2   Core Materials - Iron 34.6%, Oxygen 29.5%, Silicon 15.2%, Magnesium 12.7%, Nickel 2.4%, Sulfer 1.9%, Titanium .05%