An instrument that blocks out the bright light of a star or the Sun's disk to reveal much fainter surrounding objects like stellar coronae or exoplanets. It uses an opaque disk or advanced optical techniques to create an artificial eclipse effect.
From Latin 'corona' (crown) and Greek 'graphos' (writing/recording), originally meaning 'crown recorder.' Invented in 1930 by French astronomer Bernard Lyot to study the Sun's corona without waiting for natural eclipses, the term later expanded to include stellar applications for exoplanet detection.
The coronagraph essentially creates a permanent solar eclipse in the lab - Lyot's original invention let astronomers study the Sun's corona every day instead of waiting years between natural eclipses! Modern space-based coronagraphs are so sensitive they could theoretically detect a candle flame next to a searchlight from thousands of miles away.
Complete word intelligence in one call. Free tier — 50 lookups/day.