![Light curve of Algol (Beta Persei), an eclipsing variable, or eclipsing binary, star system. The …[Credits : Encyclopædia Britannica, Inc.]](http://media-2.web.britannica.com/eb-media/70/52570-004-74B56383.gif)
Light curve of Algol (Beta Persei), an eclipsing variable, or eclipsing binary, star system. The relative brightness of the system is plotted against time. A sharp dip occurs every 2.9 days when the fainter component star eclipses the brighter one, a shallower dip when the brighter star eclipses the fainter one.
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