Besides mass, the other factor that influences where a star appears on the main sequence is:

Question

Quizplus · Accepted Answer

The chemical composition of the cloud from which a star forms determines its mass and therefore its position on the main sequence. Stars with higher metallicity (higher amounts of elements heavier than hydrogen and helium) tend to be more massive and therefore appear higher on the main sequence. The chemical composition of the cloud from which a star forms determines its initial fuel source (i.e. hydrogen or helium) and thus, its temperature and luminosity. This ultimately determines where it will appear on the main sequence.

Besides Mass, the Other Factor That Influences Where a Star