Once Astronomers Obtain the Apparent Magnitude for a Cepheid Variable

question 57

Multiple Choice

Once astronomers obtain the apparent magnitude for a Cepheid variable star by direct observation and the absolute magnitude from the period-luminosity relation, what do they need to use to find its distance?

• A) the H-R diagram (spectroscopic parallax)
• B) the distance-magnitude relationship
• C) the Stefan-Boltzmann relationship
• D) parallax

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