What is the definition of inner core?

The Earth's inner core is the Earth's innermost part. It is primarily a solid ball with a radius of about 1,220 kilometres, which is about 70% of the Moon's radius. It is composed of an iron–nickel alloy and some other elements. The temperature at the inner core's surface is approximately 5,700 K, which is about the temperature at the surface of the Sun. read more

The inner core of the Earth, its innermost part, is a primarily solid ball with a radius of about 1,220 km, according to seismological studies. It is believed to consist primarily of an iron–nickel alloy, and to be about the same temperature as the surface of the Sun: approximately 5700 K. read more

Video: Inner Core of the Earth: Definition, Composition & Facts The inner core is located at the center of the Earth and is composed of nickel and iron. Most of what we know about the inner core is through studying seismic waves. read more