Page:Illustrated Astronomy.pdf/29





CONVECTIVE ZONE

The convective layer ranges from 500,000 km to almost its visible surface. Here, energy does not travel by radiation, but by convection. The cooling-down process happens differently from the previous layer because the Sun’s material moves as heat “bubbles” (convective cells) —which comes from the Tachocline and expand, making them “float” or moving upwards — carrying this innermost part heat to the outermost ones. Through the movement of this material (plasma state), the temperature cools down from about 2,000,000 °C in the Tachocline to 6000 °C in the photosphere, which is the following layer.

DID YOU KNOW THAT…

...the movement of material in the solar surface produces the so-called Granulation and Supergranulation? • • • 29