If you plot the positions of thousands of stars on the H-R diagram, most of those stars fall along the main sequence. Why are so many stars found along this line rather than in other parts of the diagram?

Question

Quizplus · Accepted Answer

The main sequence on the H-R diagram is where stars are fusing hydrogen to form helium in their cores, and it corresponds to a stable phase of a star's life. As long as there is enough fuel to consume, a star will remain on the main sequence. Therefore, most stars are found on this line because they are in this stable phase of their lives. Option A is incorrect because the amount of atomic power a star has is not the main factor in determining its position on the H-R diagram. Option B is incorrect because high-mass stars actually consume their fuel at a much faster rate than low-mass stars. Option D is also incorrect because low-mass stars can remain on the main sequence for billions of years if they have enough fuel.

If You Plot the Positions of Thousands of Stars on the H-R