Cataclysmic variable star

Stars with irregular large fluctuations in brightness

In astronomy, cataclysmic variable stars (CVs) are stars which irregularly increase in brightness by a large factor, then drop back down to a quiescent state. They were initially called novae (from Latin 'new'), since those with an outburst brightness visible to the naked eye and an invisible quiescent brightness appeared as new stars in the sky. Cataclysmic variable stars are binary stars that consist of two components; a white-dwarf primary, and a mass-transferring secondary.

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