noun
: a law in astronomy: the period of light variation of a Cepheid variable is in direct relation with its absolute magnitude whereby intrinsically fainter stars have the shorter periods
noun
: a law in astronomy: the period of light variation of a Cepheid variable is in direct relation with its absolute magnitude whereby intrinsically fainter stars have the shorter periods
Webster's New International English Dictionary. Новый международный словарь английского языка Webster. 2012