What is the Sun's Corona?

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When the moon passes completely in front of the Sun during an eclipse, a glowing halo shines out. This is known as Corona or Sun's atmosphere. But it, in no way, resembles our atmosphere. It has a temperature of a million degrees centigrade and is a million times thinner than air. Normally, it hides from the view due to the Sun's brilliance except during an eclipse The Corona contains hydrogen, nitrogen oxygen and other common elements. They are very hot and scattered far apart. Unlike our atmosphere, which is held to the Earth by gravity, corona is pouring off into space at a speed of about 400Km/s. These clouds of atoms pass the planets and the Sun towards the stars. This movement of atomic particles is called solar wind.

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