Multiple Choice
What is a Cepheid variable?
A) It is a bright source of variable X-ray emission,thought to harbor a supermassive black hole.
B) It is a type of very luminous star that makes an excellent standard candle.
C) It is a main-sequence star of spectral type B5.
D) It is a type of galaxy that varies in its light output.
Correct Answer:
Verified
Correct Answer:
Verified
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