Photospheric Magnetism and the Magnetic Network

Photospheric Magnetism and the Magnetic Network

. A high-resolution magnetic map of the quiet part of the photosphere, obtained using the Michelson Doppler Imager (MDI) aboard SOHO, is overlaid with lines of convergence of the horizontal flow, describing the magnetic network. Green circles show the convergence points, red arrows describe the inferred down-flow and blue arrows describe the inferred up-flow. The magnetic field in the photosphere is shown light gray for positive fields directed out of the Sun and black for negative fields pointing in. Magnetic flux disappears in collisions between opposite polarities so fast that all magnetic fields should vanish in a few days. New flux emerging in small ephemeral regions replaces the disappearing flux. (Courtesy of the SOHO MDI consortium. SOHO is a project of international cooperation between ESA and NASA.)

Copyright 2010, Professor Kenneth R. Lang, Tufts University