The action within the Sun whereby the kinetic energy of the hot, highly ionized gas of the solar interior is converted into the magnetic field that gives rise to solar activity. In the picture due to H. W. Babcock, magnetic field lines under the photosphere running from pole to pole (the poloidal field) are twisted parallel to the equator (the toroidal field) by the Sun's differential rotation. Active regions, including sunspots, are thought to be generated as the distorted magnetic field lines rise through the photosphere. Convection currents gradually turn the toroidal field into a poloidal field of the reverse direction for the next cycle.
Subjects: Astronomy and Astrophysics.