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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 core, or the center of the Sun, is the region where the energy of the Sun is produced. Even on Earth we know that the Sun produces energy because we see sunlight and we feel hot on a summer day.

The Sun's energy, which is produced in the core, travels outwards. The energy travels first through the radiative zone, where particles of light (photons) carry the energy. It actually takes millions of years for a photon to move to the next layer, the convection zone.

At the convection zone, energy is transferred more rapidly. This time it is the motion of the gases in the Sun that transfers 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, and is called granulation.

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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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part by the National Science Foundation and NASA, our Founding Partners (the American Geophysical Union and American Geosciences Institute) as well as through Institutional, Contributing, and Affiliate Partners, individual memberships and generous donors. Thank you for your support! NASA AGU AGI NSF