Here's why:

* Photosphere: This is the visible surface of the Sun, the layer we see with our naked eyes. It's about 400 km thick and emits most of the Sun's light and heat.

* Chromosphere: This layer lies above the photosphere and is only visible during total solar eclipses, appearing as a reddish ring.

* Corona: This is the outermost layer of the Sun's atmosphere and is also only visible during total solar eclipses, appearing as a faint, white halo.

While the chromosphere and corona are technically layers of the Sun, they are too faint to be seen without special equipment or during specific circumstances.