variable star

American  

noun

Astronomy.

1. a star that varies markedly in brightness from time to time.

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variable star British  

noun

1. any star that varies considerably in brightness, either irregularly or in regular periods. Intrinsic variables, in which the variation is a result of internal changes, include novae, supernovae, and pulsating stars See also eclipsing binary

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variable star Scientific  

1. A star whose actual or observed brightness varies periodically. These changes can occur with varying degrees of regularity and intensity, over times ranging from a fraction of a second to many years. Intrinsic variation occurs because of changes of the star itself, often due to internal vibration or eruptions, or to influx of nearby material. Cepheids and novae are examples of intrinsically variable stars. Extrinsic variation in a star's observed brightness that does not reflect physical changes in the star also occur, as when a darker star periodically eclipses a brighter star in an eclipsing binary system, or with the rotation of a star.

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Etymology

Origin of variable star

First recorded in 1780–90

Example Sentences

These ladders are built from objects such as supernovae and special stars called Cepheid variable stars.

From Science Daily

HP Tau is known as a T Tauri star, a type of young variable star that hasn't begun nuclear fusion yet but is beginning to evolve into a hydrogen-fueled star similar to our Sun.

From Science Daily

A key rung relies on observations of variable stars called Cepheids.

From Science Magazine

The approaches include looking at supernovae and variable stars in distant galaxies and measuring how fast they’re receding, as well as how far away they are.

From Scientific American

Much of their work was on variable stars.

From Scientific American