Previously scientists had estimated that the center of the Earth was 5,000 degrees Celsius. That estimate was made nearly twenty years ago. Now the estimated temperature is 6,000 degrees Celsius which makes more sense due to the Earth’s magnetic field requiring at least 1,500 degrees difference between the core and the mantle superficial to it in order to fit into current geophysical models. A team of scientists led by Agnes Dewaele from the French national technological research association CEA, along with other research groups conducted experiments to find the new temperatures. At temperatures above 4,000 degrees Celsius and the pressure of at least 1.3 million atmospheres iron is as liquid as water in oceans. This is true except for the very center of the Earth. The iron in the core of the Earth is under such intense pressure and heat that it solidifies. For more information on how the experiment was conducted and how it changed the previous temperature estimate head over to Science Daily in the link below.
Source: Science Daily
image: Credit to Science Daily and ESRF
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