Astronomy Practice Exam

Which zone of the Sun is characterized by the movement of gas in convection currents?

1. Radiation Zone

2. Photosphere

3. Convection Zone

4. Core

The correct answer is: Convection Zone

The correct choice is the Convection Zone, where the movement of gas in convection currents is a defining characteristic. In this layer of the Sun, energy is transported predominantly through convection, which is the process of hot plasma rising to the surface while cooler plasma sinks back down. This cycle creates convection cells that facilitate the transfer of heat from the inner layers of the Sun to the outer layers. As the gas is heated, it becomes less dense, causing it to rise towards the surface. Upon reaching the surface, it cools, increases in density, and then sinks back down to be reheated, creating continuous circulation. This dynamic process not only plays a crucial role in transferring solar energy but also contributes to solar phenomena such as sunspots and solar flares. In contrast, the Radiation Zone is characterized primarily by energy being transferred through radiation rather than convection, where photons move outward through this dense region at a slow pace due to frequent absorption and re-emission processes. The Photosphere, which is the visible surface of the Sun, is where the light we see is emitted, but it is not the layer where convection currents dominate. The Core is the innermost region of the Sun, where nuclear fusion occurs, and while energy is produced here, it