The Fabulous Discovery of the Solar Eclipse Corona

Prof. Serge Koutchmy

  The history of the discovery of the solar corona is tentatively discussed taking into account both socio-psychological factors and objective factors leading to its scientific study.

The hypothesis about the possible observation of the solar corona and its mythic interpretation in the early Antiquity, at time of total solar eclipses, is considered. The winged Sun is indeed a recurrent topic found in the vestiges of many civilisations, especially in the ancient Egypt . This picture could have been inspired by the viewing of coronal equatorial streamers discovered during total eclipses of the Sun. Prominences could have as well been observed.

We further consider the enigmatic absence of any report about the solar corona and several reasons explaining why it is forgotten for almost 2000 Years, at least in the western world.

The corona was then rediscovered during the 19th century, thanks to observations performed at time of solar total eclipses whose mechanism is now well understood. Practical maps are computed, including the prediction of the position of the line of totality at the surface of the Earth and the precise timing of the occultation which make easy the planning of scientific observations.

Modern observations and images of the solar corona are performed routinely by artificial eclipses produced at ground using the Lyot coronagraph and, more recently, on space-born instruments. An additional X-ray corona is now studied. However its origin is a matter of hot debates as the origin of the classical corona continues to be.