What is the approximate temperature of the Earth's inner core?

Earth's internal engine is running about 1,000 degrees Celsius (about 1,800 degrees Fahrenheit) hotter than previously measured, providing a better explanation for how the planet generates a magnetic field, a new study has found.

A team of scientists has measured the melting point of iron at high precision in a laboratory, and then drew from that result to calculate the temperature at the boundary of Earth's inner and outer core — now estimated at  6,000 C (about 10,800 F). That's as hot as the surface of the sun.

The difference in temperature matters, because this explains how the Earth generates its magnetic field. The Earth has a solid inner core surrounded by a liquid outer core, which, in turn, has the solid, but flowing, mantle above it. There needs to be a 2,700-degree F (1,500 C) difference between the inner core and the mantle to spur "thermal movements" that — along with Earth's spin — create the magnetic field.