Why do we need sun and rain to see a rainbow?

Have you ever been outside when the sun peeks out during a rain shower? The air smells fresh and wet. Puddles shine on the ground. And then, high in the sky, a rainbow glows.

A rainbow shows up when sunshine and rain meet. So why do we need the sun and the rain to see a rainbow? Let's find out together.

Sunshine on a wall looks plain and bright. Yet hidden inside sunlight are all the colors of the rainbow. They are mixed up together, so we cannot see them one by one. The sun brings the colors.

Rain fills the sky with droplets, which are small drops of water falling through the air. Each droplet is round and clear, like a glass bead. The rain brings the droplets.

Sunlight shines into each droplet. The droplet bends the light as it goes through, just like water makes a straw in a glass look bent. What do you think happens to the mixed-up colors when the light bends?

The colors spread apart! Each color bends a little differently, so they slide away from each other. Red, orange, yellow, green, blue and purple come out side by side.

Every droplet sends its colors out toward your eyes. So many droplets shine together that their colors join up. They make one big curved stripe of colors in the sky. That stripe is the rainbow.

Without the sun, there is no light to bring the colors. Without the rain, there are no droplets to spread them apart. That is why a rainbow needs both at once.

Here is our special word: droplets. Sunlight shines into rain droplets, and the droplets spread its hidden colors into a rainbow.

Next time sunshine meets rain, may you spot a rainbow glowing just for you.