Mira variables are not as useful as other variable stars in making astronomical calculations because:
A)their periods are not always regular.
B)their periods are too long to be measured easily.
C)there are relatively few of them.
D)no Mira variables are close enough for a parallax measurement.

Question

Quizplus · Accepted Answer

Mira variables have irregular periods, which makes them less useful in making astronomical calculations compared to other variable stars with more regular periods.

Mira Variables Are Not as Useful as Other Variable Stars