- Corona is the outermost layer of the Sun.
- It experiences a very high temperature, about one million degrees Celcius.
- It starts at about 2100 km above the photosphere.
- Corona isn't visible from the earth (except during solar eclipse).
- The corona does not have an upper limit.
- Photosphere, the Chromosphere, the Transition Region, and the Corona are the outer layers of the sun.
- Granules on the sun's photosphere are due to the convection currents of plasma within the Sun's convective zone.