What Lies Beneath A Sunspot

What Lies Beneath A Sunspot

. The temperature and flow structure under a sunspot have been probed using local helioseismology techniques with data obtained by the Michelson Doppler Imager instrument aboard the SOlar and Heliospheric Observatory, or SOHO for short. The intense magnetic fields in and below a sunspot act as a plug that prevents the up-flow of energy from the hot solar interior. As a result, the sunspot is cooler and darker than its surroundings (dark blue region in the bottom cross section). Heat builds up below the magnetic plug, so the material underneath the sunspotís magnetic fields becomes hotter (red area in cross section). The converging flows of surrounding cooler material, denoted by the arrows, help hold a sunspot together. (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