If the stars at the turnoff point of a cluster have a mass of 3M, what is the age of the cluster
A)$3.0×10^{10}$ years
B)$3.3×10^9$ years
C)$6.4×10^8$ years
D)$1.6×10^{11}$ years
E)The age of a star cluster cannot be determined from the mass of stars at the turnoff point.

Question

Quizplus · Accepted Answer

The age of a star cluster can be estimated from the mass of stars at the turnoff point using the mass-luminosity relation, which implies that more massive stars burn their fuel faster and thus have shorter lifespans. A star with a mass of 3M (where M is the mass of the Sun) would have a significantly shorter lifespan than the Sun. Given the options, $6.4×10^8$ years is a reasonable estimate for the age of a cluster with a turnoff point at 3M, as more massive stars live shorter lives.

If the Stars at the Turnoff Point of a Cluster 3.0×10103.0×10^{10}3.0×1010

If the Stars at the Turnoff Point of a Cluster $3.0×10^{10}$