GENERAL GEOLOGY

Detailed explanation-1: -The pressure and density are simply too great for the iron atoms to move into a liquid state. Because of this unusual set of circumstances, some geophysicists prefer to interpret the inner core not as a solid, but as a plasma behaving as a solid.

Detailed explanation-2: -The solid iron-nickel inner core-today 1, 200 kilometers (745 miles) in radius, or about three-quarters the size of the moon-is surrounded by a fluid outer core of molten iron and nickel about 2, 400 kilometers (1, 500 miles) thick.

Detailed explanation-3: -The inner core is solid because it is made of very dense, or heavy, materials-like iron and nickel. Even though it is very hot, these materials don’t “melt” very easily, so they stay solid.

Detailed explanation-4: -Earth’s inner core is the innermost geologic layer of planet Earth. It is primarily a solid ball with a radius of about 1, 220 km (760 mi), which is about 20% of Earth’s radius or 70% of the Moon’s radius.

Detailed explanation-5: -As a result of this, we can learn that the Earth has a liquid outer core, a solid mantle exterior to that, and a solid core interior to it! So that’s how come the Earth has the heaviest, densest elements at its core, and how we know its outer core is a liquid layer.