| 单词 | period–luminosity |
| 释义 | > as lemmasperiod–luminosity period–luminosity adj. Astronomy designating or relating to a law relating the period of a variable star, esp. a cepheid, to its luminosity, used in establishing its distance from the earth. ΘΚΠ the world > the universe > star > kind of star > by light > [adjective] > variable variable1788 irregular1903 period–luminosity1918 1918 H. Shapley in Contrib. Mt. Wilson Solar Observatory No. 153. 2 For parallaxes obtained with the period-luminosity curve the accuracy appears to surpass that of direct measures on any object for which the parallax is less than 0″·01. 1950 Sci. News 15 46 From the period-luminosity relation we then find the absolute magnitude, and so, knowing both m and M we can find the distance. 1992 S. P. Maran Astron. & Astrophysics Encycl. 21/1 The distance derived for the Cepheids from the period–luminosity relation placed M31 well beyond the bounds of our Milky Way. < as lemmas |
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