What causes a meteor shower?

A meteor shower occurs when Earth moves through clouds of debris that have been left behind by a comet as it travels through the solar system. Comets typically shed material during their orbits, creating trails of dust and small particles. When these particles enter Earth's atmosphere at high speeds, they burn up upon entry, creating the bright streaks of light known as meteors. This process is a recurrent event corresponding to specific times of the year, often linked with particular comets, leading to annual meteor showers.

Other processes, such as asteroid collisions or supernova explosions, do not result in meteor showers. While asteroids can produce meteorites if they collide with Earth, they do not create the widespread meteor showers observed in conjunction with comets. Similarly, changes in gravitational pull relate to tides and other celestial mechanics but are not a contributing factor to meteor showers. The core mechanism of meteor showers links directly to the Earth’s passage through cometary debris, making the correct answer clearly focused on this relationship.