Granulation

Definition

Granulation refers to the pattern of small, bright cells on the surface of the Sun, caused by convection currents. These cells are known as granules and are typically around 1,000 kilometers in diameter.

5 Must Know Facts For Your Next Test

1. Granules are formed by hot plasma rising to the surface and then cooling and sinking back down.
2. Each granule lasts for about 8 to 20 minutes before dissipating.
3. The edges of granules appear darker because the plasma is cooler there.
4. Granulation patterns can be observed using high-resolution solar telescopes.
5. The study of granulation helps astronomers understand convective processes in the Sun's photosphere.

Review Questions

• What causes the formation of granules on the Sun's surface?
• How long does a typical granule last before dissipating?
• Why do the edges of granules appear darker?

Related terms

Photosphere:

The visible surface layer of the Sun from which most of its light is emitted.

Convection Zone: The layer within the Sun where energy is transported outward by convection currents.

Plasma:

A state of matter consisting of ionized gas with free electrons and ions, found extensively in stars including the Sun.