Stars don't actually flicker, but they appear to do so because of the Earth's atmosphere. Here's why:

* Turbulence: The air in our atmosphere is constantly moving and churning, creating pockets of different densities.

* Light Bending: As starlight travels through these pockets, it gets bent (refracted) in different directions.

* Varying Intensity: This bending causes the light to reach our eyes in a fluctuating way, making the star appear to twinkle or flicker.

Think of it like this: Imagine looking at a star through a glass of water. The water's movement and unevenness will make the light from the star appear to dance and flicker.

Note: This flickering effect is more noticeable for stars lower in the sky because their light has to travel through more of the atmosphere.