Photosphere. This is the surface of the Sun. It’s the lowermost layer of the star we can see and what we use to measure the diameter of the Sun. The photosphere is about 400 kilometers (250 miles) thick, and temperatures there reach about 5,700°C (10,300°F). Sunspots, solar flares, and prominences form in the photosphere, but they are the result of the processes happening in other layers. Like a chocolate crust, the photosphere surrounds the inner layers of the Sun.

Atmosphere. This zone unites several layers: photosphere, corona, and transitional region. The atmosphere can be seen using special devices, and you can see it with a naked eye during a solar eclipse.

Chromosphere. This is a thin layer of transparent gas above the photosphere. The chromosphere is about 2,000 kilometers (1,250 miles) thick and riddled with jets of hot gas. It has a pinkish color and the temperature rises with height.

Transition region. This is the area between the chromosphere and corona. The layers below this region are under the influence of gravity, gas pressure, and energy exchange. And those above are dominated by magnetic forces.

Corona. This is the topmost part of the atmosphere where you can see the features like solar prominences, flares, and coronal mass ejections. It’s the outermost layer of the solar atmosphere and it can extend millions of kilometers into space. Gases in the corona burn at about 1 million degrees Celsius (1.8 million degrees Fahrenheit) and move about 145 kilometers (90 miles) per second. You can see the corona with your naked eye during a full solar eclipse.

Comments to article «What the Sun Is Made Of»