Solar corona, July 6th 1936.
© Science Museum / Science & Society Picture Library
This photograph was taken with Lyot's 'coronagraph' at the observatory at the Pic du Midi, France, at 0800 hours. A corona is the rarified gaseous envelope of the sun, seen as an irregularly shaped area of light around the moon's disc during a total solar eclipse. Bernard Ferdinand Lyot (1897-1952) was the French astromomer who invented the coronagraph in 1930. This device allows the sun's corona to be observed without the necessity for a total solar eclipse. This is achieved by creating an artificial eclipse inside a telescope with very precisely aligned optics.