period-luminosity relation

[peer-ee-uhd-loo-muh-nos-i-tee]

noun

Astronomy.

1. the relationship between the period of light variation and of the absolute magnitude of Cepheid variable stars.

Word History and Origins

Origin of period-luminosity relation¹

First recorded in 1945–50

Example Sentences

Hubble was able to use his measurement of Cepheids and Leavitt’s period-luminosity relation to prove definitively that the Cepheids in Andromeda and several other nebulae were much too distant to be inside the Milky Way.

Read more on Scientific American