Why is the Sun’s corona visible during totality?

The Sun’s corona is normally invisible to the unaided eye because its light is overwhelmed by the intense brilliance of the photosphere, the Sun’s visible surface.1

During a total solar eclipse, the Moon moves directly between the Earth and the Sun, completely blocking the light from the photosphere. By obscuring this overwhelming glare, the Moon allows the much fainter light of the corona to become visible to observers on Earth. This phenomenon provides a brief window, typically lasting only a few minutes, to view the corona’s white streamers extending from the Sun.123