Cepheid Variable Stars Are Invaluable in Astronomy Because of the Close

question 137

Multiple Choice

Cepheid variable stars are invaluable in astronomy because of the close relationship between

• A) the peak wavelength of their spectra and their surface temperatures.
• B) their luminosity, or absolute magnitude, and their pulsation period.
• C) the redshift of their spectra and their distance from the Sun.
• D) their apparent magnitude and their pulsation period.

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