Earth's core is primarily composed of iron and nickel. This immense, central region is divided into two parts: a solid inner core and a liquid outer core.
The Earth's Core: A Two-Part Structure
- Inner Core: This solid sphere, approximately 1,220 km (760 mi) in radius, is subjected to immense pressure, which keeps it solid despite incredibly high temperatures ranging from 7200–9000℉ (4000–5000℃). [Source: Multiple references]
- Outer Core: Surrounding the inner core is the liquid outer core, about 1300 miles (2092 km) thick. This layer is also primarily iron and nickel but exists in a molten state due to lower pressure compared to the inner core. [Source: Multiple references]
How Do We Know?
Scientists deduce the composition of the Earth's core through various methods, including analysis of seismic waves. The way these waves travel through the Earth provides clues about the density and composition of the different layers. [Source: Reddit thread on how scientists know the Earth's core composition]
Recent Discoveries
Recent research has uncovered a doughnut-shaped region within the liquid outer core. This discovery provides additional insights into the dynamic processes occurring deep within the Earth. [Source: Science Daily and Phys.org articles on the doughnut-shaped region].
The Earth's core plays a critical role in generating the planet's magnetic field. The movement of molten iron within the outer core creates electric currents, which in turn generate the magnetic field that protects us from harmful solar radiation. [Source: Implied across multiple sources, particularly National Geographic]
