Why doesn't the Sun fuse all its hydrogen at once and explode like an H-bomb?

Fortunately for life on our planet, the Sun gradually releases its nuclear energy over billions of years.


Asked by: Edward Seymour, Hove

The Sun is powered by the energy released when the nuclei of its hydrogen atoms slam together so hard they fuse together. As these nuclei are protons with the same positive charge, they repel each other, so it takes incredibly high temperatures in excess of around 15,000,000°C to persuade them to fuse together. But such conditions exist only in the Sun’s intensely hot, dense core, which makes up barely 1 per cent of its total volume.

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