What are the layers that make up the Earth and approximately how thick is each layer?
From the boundary with the outer core to the center of the Earth, a distance of about 1220 km is the solid sphere of the inner core, a ball of incredibly hot iron-nickel alloy. Temperatures here reach between 5,000 and 7,000 degrees C, and pressures are calculated to be around 3,000,000 units of atmospheric pressure. Despite the high temperature, at these pressures the metals cannot remain molten.
