Short-Question

Practical answers to complex questions

# Why is the area under a rainbow lighter?

## Why is the area under a rainbow lighter?

Thus, the inner part of the rainbow is brighter because light is being focused by the raindrops at the center of the rainbow, while at angles outside the rainbow the geometry is wrong so little extra light comes back.

Why is a rainbow darker above than below?

Light is very poorly reflected by raindrops at certain angles above the primary rainbow, which makes the sky look very dark there in comparison to the brighter light below the rainbow.

What explains why the sky is darker between the primary and secondary rainbows than above the secondary or below the primary?

Actually this darkened strip of sky between the primary and secondary bows is due to the reflection (and refraction) of sunlight in raindrops — the dark band is deprived of this light. Essentially only scattered sunlight reaches this region.

### Why can you see a rainbow only when the sun is low in the sky?

Rainbows are formed when sunlight is scattered from raindrops into the eyes of an observer. The sun needs to be low in the sky, at an angle of less than 42° above the horizon. The lower the sun in the sky the more of an arc of a rainbow the viewer will see.

Why is secondary rainbow fainter?

Because of the additional reflection, the colors in the secondary rainbow are reversed in order compared to the primary rainbow. Since some light is lost out of the raindrop with every reflection, the secondary rainbow is much fainter than the primary rainbow.

Why primary rainbow is brighter than a secondary?

A primary rainbow is brighter than the secondary rainbow because there is one less reflection inside the water drops. Because more light departs from two reflections than that from one, and since the rainbow itself would be distributed over a larger part of the sky, the secondary rainbow is brighter than the first.

## Is there an end of the rainbow?

You can’t reach the end of the rainbow because a rainbow is kind of like an optical illusion. A rainbow is formed because raindrops act like little prisms. The raindrops split light up into bands of color. The colors you see in a rainbow come from millions of raindrops that are sitting at different angles in the sky.