A
corona (Latin, '
crown') is an aura of
plasma that surrounds the
sun and other celestial bodies. The Sun's corona extends millions of kilometres into space and is most easily seen during a total
solar eclipse, but it is also observable with a
coronagraph. The word "corona" is a
Latin word meaning "crown", from the
Ancient Greek κορώνη (korōnè, “garland, wreath”).