If the stars at the turnoff point of a cluster have the same mass as the Sun, what is the approximate age of the cluster?

Question

Quizplus · Accepted Answer

The turnoff point of a cluster refers to the point on the Hertzsprung-Russell diagram where stars begin to leave the main sequence. The age of the cluster can be estimated based on the mass of stars at this point. Stars with the same mass as the Sun (1 solar mass) have a main sequence lifetime of approximately 10 billion years. Therefore, if the stars at the turnoff point have the same mass as the Sun, the cluster is approximately 10 billion years old.

If the Stars at the Turnoff Point of a Cluster