Nuclear Fusion

Demonstrate an understanding that the Sun's energy is generated by nuclear fusion reactions at its core, converting hydrogen into helium

The Sun consists primarily of the elements Hydrogen and Helium.

The Sun is large enough and contains enough mass that the internal pressure at its centre (its core) is so hot (14 million °C) that it forces the nuclei of the hydrogen atoms to join together (to fuse) to make helium atoms in a process called the proton-proton chain.

A nuclear reaction (fusion) takes place and large amounts of light and heat are produced. 600 million tonnes of hydrogen are converted into 596 million tonnes of helium every second. The remaining four million tonnes gets converted into heat and light.



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Interesting Energy FactsThe Sun's Energy

Astronomy Notes The Sun's Power Source


What elements are involved in the nuclear process inside the Sun?

Did you know?

The Sun is 5 billion years old and considered to have already used up half its hydrogen gas.