Cepheid
Americannoun
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Cepheids
plural
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Any of a class of variable stars whose luminosity fluctuates with an extremely regular period. There is a strong correlation between the absolute magnitude of a Cepheid's luminosity and its period. By comparing the apparent magnitude of a Cepheid to the absolute magnitude corresponding to its period, it is possible to determine fairly accurately how distant the Cepheid is from Earth.
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Also called Cepheid variable
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Noun Inflected Forms
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Chief Executive Rainer Blair said the company continued on a steady recovery path, with strength in bioprocessing and better-than-expected life sciences results largely offsetting a softer first-quarter respiratory season for its Cepheid unit.
From The Wall Street Journal ● Apr. 21, 2026
These include Cepheid variable stars, which brighten and dim in predictable ways, red giant stars with known brightness, Type Ia supernovae, and certain galaxy types.
From Science Daily ● Apr. 12, 2026
The Washington, D.C.–based conglomerate makes medical and scientific tools, spanning research to diagnostics, including Covid tests by its Cepheid division—one of the first-approved and widely used versions.
From Barron's ● Jan. 8, 2026
He calculated M31’s distance as a prodigious 900,000 light years away, though he underestimated its true distance – about 2.5 million light years – by not realizing there were two different types of Cepheid variables.
From Salon ● Feb. 14, 2025
Hubble did the exact same thing with Cepheid stars.
From "Zero: The Biography of a Dangerous Idea" by Charles Seife
The distance ladder method involves measuring objects, like bright stars called Cepheids or stars at the tip of the red giant branch, and comparing them to objects further away to determine the rate of expansion.
From Salon ● Dec. 9, 2024
Webb slices though the dust and naturally isolates the Cepheids from neighboring stars because its vision is sharper than Hubble's at infrared wavelengths.
From Science Daily ● Mar. 11, 2024
A key rung relies on observations of variable stars called Cepheids.
From Science Magazine ● Oct. 31, 2023
Researchers at the University of Warsaw measured the positions of 2,431 supergiant stars known as Cepheids using the Optical Gravitational Lensing Experiment telescope at Las Campanas Observatory in Chile.
From Nature ● Aug. 6, 2019
But unlike Hubble’s dim Cepheids, supernovas are visible halfway across the universe.
From "Zero: The Biography of a Dangerous Idea" by Charles Seife
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