Earth's Interior
The interior of Earth plays an important role in plate tectonics. Scientists believe it is also responsible for Earth’s magnetic field. This field is vital to life because it shields the planet’s surface from harmful cosmic rays and from a steady stream of energetic particles from the Sun known as the solar wind. Composition of the Interior Earth’s interior consists of the mantle and the core . The mantle and core make up by far the largest part of Earth’s mass. The distance from the base of the crust to the center of the core is about 6,400 km (about 4,000 mi). Scientists have learned about Earth’s interior by studying rocks that formed in the interior and rose to the surface. The study of meteorites , which are believed to be made of the same material that formed the Earth and its interior, has also offered clues about Earth’s interior. Finally, seismic waves generated by earthquakes provide geophysicists with information about the composition of the interior. The sudden mov