Dario Alfè, David Price and Mike Gillian of University College London used a Cray T3E supercomputer to calculate that the melting point of iron was 6700 Kelvin, plus or minus 600 Kelvin, at the pressure of the inner core boundary. The inner and outer cores store tremendous amounts of energy as heat. The transfer and movement of this energy can cause earthquakes and volcanoes. It can also influence the motion of continental plates. Moreover, the magnetic field generated by the molten core protects the Earth from the solar wind.

"The core temperature is crucial for our understanding of how the Earth changes over time," says Mike Gillian. "You have to know this if you want to understand earthquakes on a fundamental level."