An H-R diagram for a globular cluster will show a horizontal branch-a line of stars above the main-sequence but to the left of the subgiants and red giants.Which of the following statements about these horizontal branch stars is true?
A)They have inert (non-burning)carbon cores.
B)Their sole source of energy is hydrogen shell burning.
C)They generate energy through both hydrogen fusion and helium fusion.
D)In a particular star cluster,all horizontal branch stars have the same spectral type.

Question

Quizplus · Accepted Answer

Horizontal branch stars generate energy through both hydrogen shell burning around an inert helium core and helium fusion in the core itself. This dual process is characteristic of their phase in stellar evolution.

An H-R Diagram for a Globular Cluster Will Show a Horizontal