Wiktionary
n. (context star English) A radially pulsating (expanding and contracting) variable star with a regular period and known relationship between period and intrinsic brightness.
Wikipedia
RS Puppis is one of the brightest known Cepheid variable stars in the Milky Way galaxy; image, Hubble Space Telescope
]] A Cepheid variable ( or ) is a type of star that pulsates radially, varying in both diameter and temperature and producing changes in brightness with a well-defined stable period and amplitude.
A strong direct relationship between a Cepheid variable's luminosity and pulsation period established Cepheids as important indicators of cosmic benchmarks for scaling galactic and extragalactic distances. This robust characteristic of classical Cepheids was discovered in 1908 by Henrietta Swan Leavitt after studying thousands of variable stars in the Magellanic Clouds.
The term Cepheid originates from Delta Cephei in the constellation Cepheus, identified by John Goodricke in 1784, the first of its type to be so identified.
Usage examples of "cepheid variable".
She noticed that a type of star known as a Cepheid variable (after the constellation Cepheus, where it first was identified) pulsated with a regular rhythm—.
Nevertheless, Amalfi had hardly expected to see the return of He, under wholly controlled spindizzy drive, in barely a century and a half, still faintly, patchily blue-green with cultivation under cloud-banks which glared a brilliant white in the light of a nearby Cepheid variable star.
Why should beings with manlike biological requirements go from a dim red dwarf star to a planetless blue giant to a dying Cepheid variable?
He did not know a Cepheid variable from a constellation, so much of what she was trying to do was incomprehensible to him.
But the Small Cloud has been more extensively studied for some years, particularly its Cepheid variable stars.
It's a nerve poison that is extracted from plants that are only obtainable from planets belonging to a Delta-Cepheid variable type sun.