Coronagraphy is a technique used in astronomy to block out the blinding light of a star in order to observe faint objects such as planets or other celestial bodies nearby. This allows astronomers to study and analyze the properties and characteristics of these objects without the interference of the bright light from the star. Coronagraphy is particularly useful in the search for exoplanets and the study of their atmospheres, as well as the study of other faint objects in the vicinity of stars. It involves the use of special instruments and techniques to create an artificial eclipse of the star's light, revealing the objects of interest that would otherwise be hidden.