The inner core of the Earth is primarily composed of iron and nickel. Despite the extremely high temperatures, the inner core is in a solid state due to the immense pressure from the layers above it. This pressure prevents the iron and nickel from melting, keeping them in a solid form.
Scientists believe that the inner core’s solid state is crucial for generating Earth’s magnetic field. The solid inner core, along with the liquid outer core, creates the dynamo effect, which is responsible for the magnetic field that protects our planet from harmful solar radiation.