In astronomy, a light curve is a graph of light intensity of a celestial object or region, as a function of time. The light is usually in a particular frequency interval or band.Light curves can be periodic, as in the case of eclipsing binaries, cepheid variables and other variables, or aperiodic, like the light curve of a nova, a cataclysmic variable star or a supernova.The study of the light curve, together with other observations, can yield considerable information about the physical process that produces it or constrain the physical theories about it.
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A graph showing the changes in magnitude of a celestial object plotted against time. Brightness is usually measured by photometry. The usual objects studied are variable stars and eclipsing binaries.