The four outer layers of the sun are the photosphere, chromosphere, transition region and corona. The photosphere is directly observable, and it is the deepest layer of the sun.
The sun's chromosphere sits above the photosphere, and it is the second deepest layer of the sun with temperatures reaching 14,000 degrees Fahrenheit. Above that, the transition region of the sun experiences temperatures as high as 900,000 degrees, and it is positioned between the corona and chromosphere. Finally, the furthest layer from the sun is the corona, which reaches temperatures of 900,000 degrees and begins at about 1,300 miles above the photosphere.
The sun also has three inner layers called the convection zone, radiative zone and the core.