Why do stars twinkle when viewed from Earth?

Stars twinkle because the air around us is always moving, and it changes how light travels to our eyes.

Imagine you're looking at a flashlight on a boat far away in a lake. When the water moves, like waves or ripples, the light from the flashlight seems to jump around or flicker. That’s kind of what happens with stars!

The air above us is not still. It has warm and cool parts that move around, like when you blow on a hot soup, some parts are moving faster than others.

When starlight passes through this moving air, it bends or changes direction in little ways. This makes the light look like it’s jumping or flickering from our eyes. That's why we see stars twinkle!

Planets are closer to us and appear bigger in the sky than stars do. Because they're larger, their light is spread out more, so even though the air is moving, it’s harder for that flickering effect to be noticed.

So next time you look at the night sky, remember: stars aren’t magic, they’re just playing a little light game with the air!