SOLAR SYSTEM

Detailed explanation-1: -However, unlike the outer core, the inner core is not liquid or even molten. The inner core’s intense pressure-the entire rest of the planet and its atmosphere-prevents the iron from melting. The pressure and density are simply too great for the iron atoms to move into a liquid state.

Detailed explanation-2: -The earth’s core is divided into two separate regions: the liquid outer core and the solid inner core, with the transition between the two lying at a depth of 5, 156 kilometers (3, 204 miles).

Detailed explanation-3: -Earth’s inner core is solid because it is under such intense pressure from the weight of the entire planet that its atoms are held together by force. By contrast, the outer layers of Earth, while being slightly cooler (but still incredibly hot), have less pressure and thus their atomic form reverts to liquid.