What phenomenon occurs in the thermosphere?

The thermosphere is characterized by its unique temperature gradient and the presence of ions, making it the layer of Earth's atmosphere where phenomena such as the Northern and Southern Lights, also known as the auroras, occur. This spectacular display happens when charged particles from the sun interact with the Earth's magnetic field and ionosphere. As these solar particles collide with gases in the thermosphere, they release energy in the form of light, creating colorful displays primarily near polar regions.

While other atmospheric phenomena exist, they do not occur specifically within the thermosphere. Weather events happen in the troposphere, which is the atmospheric layer closest to Earth's surface. Shooting stars, or meteors, occur when meteoroids enter the atmosphere, typically in the mesosphere rather than the thermosphere. Protection from radiation primarily takes place through the ozone layer located in the stratosphere, rather than within the thermosphere. Thus, the occurrence of the Northern and Southern Lights is unique to the thermosphere, affirming that option C is the correct answer.