What Causes the ‘Glow’ of a Neon Sign?

The glowing light in a neon sign is caused by tiny particles moving really fast inside a glass tube.

Inside the tube, there’s a gas, like air, but not quite, and when you turn on the sign, electricity flows through it. This electricity hits the gas particles, making them move super quickly. As they move, they start to bump into each other and also hit the sides of the glass tube.

Every time a particle hits something, like another particle or the glass wall, it gives off light, kind of like when you bounce a ball and it makes a noise every time it hits the floor.

The color of the glow depends on what kind of gas is inside the tube. For example, if there’s neon gas, the light looks red; if it's argon gas, it might look blue or purple, like when you mix different colored paints together.

So the next time you see a bright glowing sign, imagine tiny particles dancing and bumping around inside, making all that colorful fun!