Inner Core
The Inner Core is the Earth's hottest layer, it is about the temperature of the Sun (5505°C). The Inner Core is in the middle of the Earth and it is composed of Iron and Nickel. Since all the weight of the Earth is compressed into one enourmus ball, the Inner Core is pushed together and is one giant solid ball. The Inner Core is about 1,220km in radius, or aproximatley 70% that of the Moon. An interesting fact is that the Inner Core was discovered in 1936 by woman named Inge Lehmann who was a Danish seismologist from a district in Copenhagen called Østerbro pronounced (Iss-Tah-Pbo).