Fiendish Nuclear Quiz

Q2. How much heat does one cubic metre of the Sun’s core produce, on average?

Unlucky! The answer is 20 W - about as much as a cat!

But you don’t want that on your lap! The fusion processes inside the sun occur very slowly: the probability of two hydrogen atoms fusing together is very low, so only few of the many atomic collisions that occur every second result in a fusion event and release energy. The tremendous power of the Sun comes from its equally tremendous size. The fusion reactors on Earth are designed to outperform the Sun’s power density by tens of thousands of times in order to have a reasonable size for their power output.