* Hydrogen (H): About 70% of the Sun's core is hydrogen. This is the fuel source for nuclear fusion, the process that powers the Sun.

* Helium (He): About 28% of the Sun's core is helium. This is the product of nuclear fusion.

* Trace elements: The remaining 2% includes heavier elements like carbon, nitrogen, oxygen, and traces of other elements.

It's important to understand that the core of the Sun is not solid like the Earth's core. Instead, it's a plasma, a superheated, ionized gas where electrons are stripped from atoms. This plasma is under immense pressure and temperature, creating the conditions for nuclear fusion to occur.

The nuclear fusion process in the Sun's core converts hydrogen into helium, releasing an enormous amount of energy in the form of light and heat. This energy is then radiated outwards through the Sun's layers, eventually reaching Earth and providing us with warmth and light.