Our planet's core is hotter that originally thought

New measurements suggest the Earth's inner core is far hotter than prior experiments suggested, putting it at 6,000C - as hot as the Sun's surface. Measurements in the early 1990s of iron's "melting curves" - from which the core's temperature can be deduced - suggested a core temperature of about 5,000C. 

The solid iron core is actually crystalline, surrounded by liquid.But the temperature at which that crystal can form had been a subject of long-running debate.Experiments outlined in Science used X-rays to probe tiny samples of iron at extraordinary pressures to examine how the iron crystals form and melt.Seismic waves captured after earthquakes around the globe can give a great deal of information as to the thickness and density of layers in the Earth, but they give no indication of temperature.That has to be worked out either in computer models that simulate the Earth's insides, or in the laboratory.