Why Is a Rainbow Curved?

What Crafty Clover says in this video

Intro

Hi there, curious minds! I'm Crafty Clover! Let's discover something amazing. Why is a rainbow curved?

The Big Idea

A rainbow is curved because every raindrop sends colors back to you at a specific angle. All the drops at that same angle from your eyes form a circle in the sky. From the ground, you usually see only the top half of the circle, an arc!

A Set Angle

Step one: drops use a set angle. Each raindrop bounces colors back toward you at a certain angle, about 42 degrees for red light. Other colors use slightly smaller angles.

A Circle Forms

Step two: the drops make a circle. Every drop at that same angle from your eyes appears in the same color. Together, those drops form a perfect circle around a point opposite the Sun.

The Ground Cuts It Off

Step three: the ground blocks the rest. Normally the lower half of the circle is below the horizon, where there are no raindrops to see. So you see a curved arc.

A Closer Look

Let's take a closer look at a rainbow's shape! The Sun is behind you. Your eyes are the center of the view. The raindrops form a circle around the line from the Sun through your head. The ground hides the lower part, leaving an arc.

Quick Facts

Quick facts! Rainbows are really full circles. From a plane or mountain, you can sometimes see the full circle. Your rainbow is also personal: nobody else sees exactly the same one. Never look directly at the Sun. Keep it behind you.

Think Like a Scientist

Now, think like a scientist! Let's look for a full circle. Use a garden hose set to a fine mist on a sunny day, with a grown-up. Stand with your back to the Sun and look at the mist. Can you see a small rainbow arc? Don't look at the Sun.

Outro

A rainbow is a circle of light, and we see part of it. Science is amazing! Crafty Clover can be found on Amazon Books, Google Bookstore, and Apple Books. Available for purchase or download! Bye for now!