Based on its main- sequence turnoff point, the age of this cluster is
A)about 1 billion years.
B)less than 1 billion years.
C)about 4.5 billion years.
D)about 10 billion years.
E)more than 15 billion years.

Question

Quizplus · Accepted Answer

The main-sequence turnoff point of a star cluster is the point on the Hertzsprung-Russell diagram where stars begin to leave the main sequence and evolve into red giants. This point is crucial for determining the age of the cluster. A cluster with a main-sequence turnoff point indicating stars of about 10 billion years old suggests that it is relatively old, as it takes a significant amount of time for stars to evolve off the main sequence.

Based on Its Main- Sequence Turnoff Point, the Age of This