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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 interior of the Sun is made up of different layers, one inside the other. The innermost layer, the solar core, is the region where the energy of the Sun is produced. This energy travels through the next layer of the solar interior, called the radiation zone, and eventually reaches the convection zone, where energy is transferred mainly by the overturning of solar gases. This convection produces an everchanging pattern of cells on the surface of the sun.

Direct observations inside the Sun are not possible, however some diagnostics exist that allow us to study the Sun's interior.

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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