How is a Cepheid variable star identified?

Question

Question 14 options:

A)

Its brightness appears to change during transit.

B)

It's being torn apart by tidal forces.

C)

Its luminosity dims as it rotates.

D)

It pulsates radially with a clear change in luminosity.

Answer 1

The correct answer is:

D) It pulsates radially with a clear change in luminosity.

Cepheid variable stars are identified by their characteristic periodic pulsations, which result in changes in their brightness over time. These stars expand and contract, leading to variations in their luminosity that can be measured.