Figure 9-6 RIVUXG Solar Granulation High-resolution photographs of the Sun’s surface reveal a blotchy pattern called granulation. Granules are convection cells about 600 mi (1000 km) wide in the Sun’s photosphere. The inset shows rising hot gas coming up making the center of each granule bright. Cooler gas sinks downward along the boundaries between granules; this gas glows less brightly, giving the granule edges their dark appearance. This convective motion transports heat from the Sun’s interior outward to the solar atmosphere.