period-luminosity relation

American  

[peer-ee-uhd-loo-muh-nos-i-tee] / ˈpɪər i ədˌlu məˈnɒs ɪ ti /

noun

Astronomy.

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

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Etymology

Origin of period-luminosity relation

First recorded in 1945–50

Example Sentences

RR Lyrae stars can be used as standard bulbs, and cepheid variables obey a period-luminosity relation, so measuring their periods can tell us their luminosities.

From Textbooks • Oct. 13, 2016

Cepheids are scattered throughout our own Milky Way Galaxy, but the period-luminosity relation was discovered from observations of the Magellanic Clouds, a satellite galaxy now known to be about 160,000 light-years away.

From Textbooks • Oct. 13, 2016

For example, the relationships we have described such as the period-luminosity relation for certain variable stars aren’t exactly straight lines on a graph.

From Textbooks • Oct. 13, 2016

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.

From Scientific American • Feb. 10, 2012