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Period-luminosity relation
Astronomical principle / From Wikipedia, the free encyclopedia
In astronomy, a period-luminosity relation is a relationship linking the luminosity of pulsating variable stars with their pulsation period. The best-known relation is the direct proportionality law holding for Classical Cepheid variables, sometimes called the Leavitt Law.[2][3][4] Discovered in 1908 by Henrietta Swan Leavitt, the relation established Cepheids as foundational indicators of cosmic benchmarks for scaling galactic and extragalactic distances.[5][6][7][8][9][10] The physical model explaining the Leavitt's law for classical cepheids is called kappa mechanism.
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Period-Luminosity relation for Classical Cepheid variables.[1]