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Standard Candles and Variable Stars
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Astronomy
AST.192 Standard Candles and Variable Stars
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When applying an RR Lyrae standard-candle calibration, which assumption is most important?
A
The star is really an RR Lyrae and any needed metallicity or extinction correction is handled.
B
The star must be a young supergiant in a spiral arm.
C
The star's apparent magnitude must be identical to every Cepheid's apparent magnitude.
D
The star must have the same surface temperature as the Sun.
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