The stars of the Big Dipper, like all stars, are primarily made up of hydrogen and helium.

Here's a breakdown of their composition:

* Hydrogen: This is the most abundant element in the universe, making up about 75% of the Big Dipper stars' mass.

* Helium: The second most abundant element, comprising about 25% of the Big Dipper stars' mass.

These stars also contain trace amounts of heavier elements, including oxygen, carbon, nitrogen, and iron.

It's important to note that the Big Dipper is not a constellation in the true sense. It's an asterism, a recognizable pattern of stars within the constellation Ursa Major (the Great Bear). Each of these stars has its own unique composition and properties.