The Sun is mostly made of hydrogen and helium, but it also contains trace amounts of other elements. Here's a breakdown:

Major Components:

* Hydrogen (H): About 70.6% of the Sun's mass

* Helium (He): About 27.4% of the Sun's mass

Minor Components:

* Oxygen (O): About 0.8%

* Carbon (C): About 0.3%

* Neon (Ne): About 0.2%

* Iron (Fe): About 0.1%

Trace Elements:

The Sun also contains tiny amounts of other elements like:

* Nitrogen (N)

* Silicon (Si)

* Magnesium (Mg)

* Sulfur (S)

* And more, in even smaller quantities.

Important Note: These percentages are by mass. By number of atoms, hydrogen is even more dominant.

How do we know the Sun's composition?

We use spectroscopy. Light from the Sun is passed through a prism, which separates it into its different wavelengths. Each element has a unique "fingerprint" of wavelengths that it absorbs and emits. By analyzing these fingerprints, we can identify the elements present and their relative abundance.