What makes variable stars useful in determining star distances?
A) Their exact location in the H-R diagram is known.
B) They are brighter than other stars.
C) Their luminosity can be determined from their pulsation period.
D) They are easier to spot than ordinary stars.

Question

Quizplus · Accepted Answer

Variable stars, such as Cepheid variables, have a known relationship between their pulsation period and luminosity, allowing astronomers to determine their absolute magnitude and thus calculate their distance.

What Makes Variable Stars Useful in Determining Star Distances