Physics, 19.12.2019 21:31 Angellbatton6763

We determine the distance of a cepheid in another galaxy by
(a) measuring its parallax.
(b) determining its luminosity from the period–luminosity relation and then applying the inverse square law for light.
(c) knowing that all cepheids have about the same luminosity and then applying the inverse square law for light.

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We determine the distance of a cepheid in another galaxy by
(a) measuring its parallax.