Seismic images of magnetic activity on the farside of the Sun that we cannot directly see from Earth. The images show sound wave travel time variations, with locations of shorter travel times appearing darker. These darker regions indicate locations where there is an accumulation of magnetic field on the far surface. The method for estimating far-side magnetic activity was developed by Charles Lindsey and Doug Braun of Colorado Research Associates, a division of Northwest Research Associates, Boulder, Colorado. Read more