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The Outer & Inner Parts of the Sun

The basic elements that make up the sun are the same as those that the Earth is formed from. However, the extreme heat of the sun causes these materials to exist only in a gaseous state. The inner part of the sun has three layers: the energy-producing core, the radiative zone and the convective zone. The outer part of the sun, or the solar atmosphere, contains a further three layers: the photosphere, the chromosphere and the corona. Once the sun's energy has reached the surface, it is released into space. Earth can then benefit from the light and heat that it produces.

The Core
- The center of the sun is the first of three inner layers. The temperature of the Sun's core is more than 28 million degrees Fahrenheit. At this temperature, the structures of atoms are broken down. Nuclear fusion reactions that take place between these separated atomic particles as they collide with each other are the sun's source of energy.
The Radiative Zone
- The second layer of the sun's interior is called the radiative zone. It is in this area that the energy produced in the core is transported to the sun's exterior, through radiation. The temperature in this area of the sun is around 9 million degrees Fahrenheit. The energy is passed randomly between atoms which store it temporarily then release it for other atoms to absorb and pass on further until the gamma rays lose enough energy to become less harmful light energy. The process of energy transfer in the radiative zone is a very slow one, often taking more than 100,000 years to reach the next layer.
The Convective Zone
- The final layer of the inner part of the Sun is known as the convective zone. Here energy from the radiative zone travels to the outer part of the sun through a process of convection at temperatures of around 10,000 degrees Fahrenheit. The bottom of this layer is extremely hot, causing substances to rise to the surface. When the material reaches the surface, it cools and falls back down to the bottom of the convective zone, causing it to circulate energy relatively fast in this layer, taking around a week to travel from the bottom of the zone to the surface.
The Solar Atmosphere
- Above the surface of the sun lies the solar atmosphere, the outer part of the sun. This can be divided into a further three layers. The first of these layers is the one that can be seen through specialized telescopes. It has a similar appearance to a surface when it is viewed from far away although the material here is still gaseous. Light energy is released into space from this layer. The chromosphere lies above the photosphere. This layer also emits light radiation. The temperatures of both of these layers are around 20,000 degrees Fahrenheit. However, the temperature rises towards the top of this layer until it reaches the final outer layer, known as the corona, which reaches a temperature of around 3 million degrees Fahrenheit. Here, magnetic fields create high temperatures in the gas that this layer is made up from. This is where ultraviolet rays are emitted from. The chromosphere and corona are only visible during a solar eclipse.

Astronomy