Interior Cross Section of the Sun

Interior Cross Section of the Sun

. The Sun is powered by the nuclear fusion of hydrogen in its core. Energy produced by fusion reactions is transported outward, first by countless absorptions and emissions within the radiative zone, and then by convection. The visible disk of the Sun, called the photosphere, contains dark, magnetic sunspots. It is enveloped by a million-degree corona. A high-speed solar wind gushes out of coronal holes.

Copyright 2010, Professor Kenneth R. Lang, Tufts University