Solar physicists performed the equivalent of sonograms of the Sun. By detecting sound waves, they explored the interior. By applying techniques similar to those used by seismologists on Earth, the scientists deduce layering, motions and temperatures inside the Sun. Flow towards poles. The MDI instrument, measuring vertical motions of the Sun's surface every minute at a million different points, generated stunning images and charts of the subsurface region called the convection zone.
Hot gas bubbles to the surface, cools and sinks.
It rotates around the Sun's axis. These discoveries should help to explain why the Sun varies so much in activity through its 11-year cycle, and the sunspots that come and go. Differences from expected temperatures. In red coloured layers, sound travels faster than predicted by the theorists. The temperature is higher than expected.