convection zone

Solar-type stars For the Sun, the convection zone is located in the outer (roughly) 30% of the interior. Once hot gas convects up to the photosphere, it emits photons into space, cools, and settles back into the star. This convective flow is the origin of stellar granules, and the departing energy is the visible light and other electromagnetic radiation that the star emits into space. (A good example of convection current is a lava lamp.)
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