What does the sun do to generate energy?
split iron atoms into nickel split
helium atoms into hydrogen fuse hydrogen
atoms into helium
fuse hydrogen atoms into carbon

Fuse hydrogen atoms into helium.

Explanation:

The Sun, unlike the Earth, is made up primarily of hydrogen gas. The Earth, on the other hand, is made up of iron, water, rock, and other elements.

The core of the sun is the hottest part of it and there's an enormous amount of pressure at it. This causes that the hydrogens atoms fuse together because of the pressure and make a reaction known as the nuclear fusion that converts those atoms into helium ones and release big amounts of energy into the solar system.

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