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WEATHER HOMESCHOOL Episode 10: How do rainbows form?

One of the greatest things we can see in the sky is a rainbow. In this episode of Weather Homeschool, we talk about how they form.

ROANOKE, Va. – Another popular questions students ask me during school visits is, “How do rainbows form?” The process might seem simple, but it’s actually pretty involved. Your back has to be facing the sun, and you most times will be looking at rain that’s moving away or toward you.

Rainbows can be seen when our backs are to the sun and we are looking at rain
Rainbows can be seen when our backs are to the sun and we are looking at rain

When the sun’s light enters the raindrop, that light gets bent (or refracted).

Sun light gets bent upon entry into a rain drop
Sun light gets bent upon entry into a rain drop

Once that light hits the other end of the drop, it is then reflected back toward you in the colors of the rainbow.

Sun light is reflected back toward you
Sun light is reflected back toward you

In some really special cases, you can get a fogbow. Because the water droplets are so tiny in fog, you don’t get the color of the rainbow. You just get a more pronounced “white-ish” color.

Sandy Reed - Christiansburg
Sandy Reed - Christiansburg

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