Magnetic field

The magnetic field of the Sun is comprised of electric currents that generates a complex field that extends out into interplanetary space to form the interplanetary magnetic field.

As the Sun's magnetic field is carried out through the solar system by the solar wind, the Sun is rotating. Its rotation winds up the magnetic field into a large rotating spiral, known as the Parker spiral, named after the scientist who first described it.

The magnetic field is primarily directed outward from the Sun in one of its hemispheres, and inward in the other. This causes opposite magnetic field directions in the Parker spiral. The thin layer between the different field directions is described as the neutral current sheet. Since this dividing line between the outward and inward field directions is not exactly on the solar equator, the rotation of the Sun causes the current sheet to become "wavy", and this waviness is carried out into interplanetary space by the solar wind.

Every eleven years the entire magnetic field of the Sun "flips" -- the north magnetic pole of the Sun becomes the south, and vice versa. The flip takes place at solar maximum.