Why does the sky go all orange and purple n red n stuff during a sunset/sunrise?

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Why does the sky go all orange and purple n red n stuff during a sunset/sunrise?

In: Earth Science

4 Answers

Anonymous 0 Comments

Because that’s the furthest sunlight travels to your eyeballs! Fair warning, I learned about this in colour theory, not science class, so hopefully someone smarter than me can clarify if I have this right and correct the bits that are wrong.

So, we see the sky as blue because particles in the air scatter blue and violet light, which our eyeballs pick up and then our brains interpret as blue sky. But the sunlight is still emitting a full rainbow of colors. At sunset, there are so, so many more particles between you and the sun. All those particles are still scattering blue light, but a lot more of the blue is scattered before it reaches your eyes. As a result, you start to see some of other colours, like reds and yellows.

As I understand it, a similar effect sometimes happens before tornados, when the sky looks greenish. Except instead of there being more particles because of distance, there’s more particles because of the instense storm. So all those particles scatter blue like with the sunset and you start seeing more yellow-orange light, same with a sunset. Except this time you’re close so you still perceive a lot of blue, as well. Just like you normally would. And our brains interpret blue light plus yellow light as looking green.

But worth noting that the sky isn’t always green before a tornado. Plus other storms or very cloudy weather might also look green. So, ya know, don’t ignore sirens or whatever.

Anonymous 0 Comments

The answer is [Rayleigh scattering](https://en.wikipedia.org/wiki/Rayleigh_scattering) .

In brief, the molecules in our atmosphere tend to scatter light at the blue end of the light spectrum *more readily* than red light.

That means with the sun high overhead, we see lots of that blue scattered light — it’s hitting our eyes from all directions in the sky.

Around sunset, with the sun low on the horizon, we’re seeing sunlight that’s had to aim “sideways” through a much longer geometrical length of the atmosphere before it reaches us. By the time it gets to us, much of the blue light has been already scattered & left behind. Leaving mainly the reddish end of the light spectrum to illuminate clouds & scatter in the sky at sunset.

Anonymous 0 Comments

The sun’s light is white, which means it has all different colors. Blue light bends more so when the sun is low in the sky the blue light has bent before it gets to you. That’s why the sky is blue when the sun is high and orange when it is low.

Anonymous 0 Comments

Rays of light bend around the earth into the red-shift zone, creating the oranges and reds on that end of the spectrum.