Temperature and composition of the Earth's core

  title={Temperature and composition of the Earth's core},
  author={Dario Alf{\'e} and M. J. Gillan and G. D. Price},
  journal={Contemporary Physics},
  pages={63 - 80}
The Earth's core is a ball of swirling hot metal at the centre of our planet, with a radius roughly one half of the Earth's radius. It is formed by two parts: a solid inner core, with a radius of 1221 km, surrounded by a shell of liquid which extends up to 3480 km from the centre. It is widely believe that the Earth's core is mainly formed by iron, or iron with up to 5 – 10% of nickel. It is also known that the core must contain a significant fraction of light impurities, in the region of 2 – 3… 

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