1911 Encyclopædia Britannica/Chromosphere

CHROMOSPHERE (from Gr. χρῶμα, colour, and σφαῖρα, a sphere), in astronomy, the red-coloured envelope of the sun, outside of the photosphere. It can be seen with the eye at the beginning or ending of a total eclipse of the sun, and with a suitable spectroscope at any time under favourable conditions. (See Sun and Eclipse.)