Schematic view of the inner structure of the Sun
Click on image for full size and a more detailed image of the interior of the Sun

The Solar Interior

To understand how our Sun works, it helps to imagine that the inside of the Sun is made up of different layers, one inside the other. The center of the Sun is called the core. It is the region where the energy of the Sun is produced. We know that the Sun produces energy because we feel hot on a summer day.

The Sun's energy travels outwards from the core. The energy travels first through the radiative zone, where particles of light carry the energy. It takes millions of years for the energy to move to the next layer, the convection zone.

At the convection zone, energy travels faster. This time it is the motion of the gases in the Sun that moves the energy outwards. The gas at this layer mixes and bubbles, like the motion in a pot of boiling water.This bubbling effect is seen on the surface of the Sun.

We can't see inside the Sun. So scientists use other diagnostics. These diagnostics help us know what is inside the Sun.

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The Convection Zone

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Diagnostics for the Solar Interior

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The Sun's Radiative Zone

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High Altitude Observatory

Scientists at the High Altitude Observatory (HAO) try to learn about the changes we see in the Sun over time. They also study how it affects the atmosphere of the Earth. There are four main areas of study...more


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Coronal Mass Ejections

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Solar Activity

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The Solar Atmosphere

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