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What makes the rock inside volcanoes so hot? © iStock

What makes the rock inside volcanoes so hot?

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Just in case you had any trouble sleeping at night, remember that we're all living on top of a planet-sized nuclear reactor.

Asked by: Anonymous


In a word, radioactivity. We’re all living on top of a vast natural nuclear reactor, packed with uranium, thorium and potassium that ended up trapped inside the Earth during its formation around 4.5 billion years ago.

As they decay, the fast-moving particles they release smash into their surroundings, dumping their energy as heat. It’s this that makes the interior of the Earth so hot, and allows lava to reach temperatures in excess of 1000°C.


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Robert is a science writer and visiting professor of science at Aston University.


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