Contradictory: Sky blue and sunset red?

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In summary, the conversation discusses the phenomenon of a blue sky during the day and red sunsets, and how they are explained by Rayleigh scattering. It is explained that blue light is scattered in the sky, and this is why we see a blue sky. The conversation also addresses confusion between scattering and absorption, and the concept of one person's gain and another person's loss in terms of seeing blue photons in the sky or the sunset. Ultimately, the conversation concludes that the sky is blue because of Rayleigh scattering and this also explains why the sun appears red during sunsets.
  • #1
Pranav Jha
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Sky is supposed to blue during the day because of maximum scattering of violet and blue light. But if they get scattered in the sky, how do they reach our eyes? With this logic i think the sky should be yellowish red during the day (which it surely isn't!)
With this notion i can understand why sunsets are red as most blue light has been scattered and the majority of visible light reaching our eyes is red.
So, what is amiss with my understanding here?
 
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  • #2
Scattered light still reaches our eyes, just from a different direction. You are confusing scattering and absorbing.
 
  • #3
duh! Indeed, I was confusing the two terms
 
  • #4
DaleSpam said:
Scattered light still reaches our eyes, just from a different direction. You are confusing scattering and absorbing.
There is no confusing of scattering and absorbing here. Just confusion. Rayleigh scattering explains both red sunsets and blue skies. There is no need to invoke the concept of absorption.

Pranav Jha, think of it as a one person's gain and another person's loss. Those blue photons you see when you look at the sky are blue photons that someone else did not see when they looked at the sunset.
 
  • #5
D H said:
Pranav Jha, think of it as a one person's gain and another person's loss. Those blue photons you see when you look at the sky are blue photons that someone else did not see when they looked at the sunset.


i don't get what you mean
 
  • #6
Suppose that Rayleigh scattering did not occur. Were that the case, our sky would be black rather than blue and the sun would appear to be the same color all day long.

Rayleigh scattering however does occur. You see a blue sky because the sky selectively scatters blue photons. Let's focus on one such photon. This photon came from the Sun, but the at a slightly different angle from the line between the Sun and you. Let's trace where that blue photon would have gone had it not been scattered. There are three possibilities: It would either have gone back out into space, it would have hit the Earth somewhere, or it would have hit someone's retina who was watching the sunset.

That the sky is blue inherently means that the Sun has to be red at sunset. There is no contradiction here.
 

1. What is the meaning of "contradictory" in this context?

In this context, "contradictory" refers to two things that are opposite or conflicting. In this case, the colors sky blue and sunset red are considered contradictory because they are typically seen as two distinct and contrasting colors.

2. How can the sky be both blue and red at the same time?

The sky appears blue during the day due to a phenomenon called Rayleigh scattering, where sunlight is scattered by the Earth's atmosphere. However, during sunrise and sunset, the angle of the sun creates a longer path for sunlight to travel through the atmosphere, resulting in shorter blue wavelengths being scattered and longer red wavelengths appearing more dominant.

3. Is it possible for the sky to be both blue and red simultaneously in different locations?

Yes, it is possible for the sky to appear both blue and red at the same time in different locations. This is due to differences in weather conditions, atmospheric composition, and the angle of the sun relative to each location.

4. Why do some people see the sky as more blue while others see it as more red during sunset?

The perception of color is subjective and can vary from person to person. Factors such as age, genetics, and past experiences can all influence how we perceive colors. Additionally, individual differences in color vision can also play a role in how someone sees the sky during sunset.

5. Can contradictory colors like sky blue and sunset red be used together in art or design?

Yes, contradictory colors can be used together in art or design to create contrast and visual interest. In fact, many artists and designers intentionally use contradictory colors to create unique and striking compositions. The concept of "contradictory colors" is subjective and can be interpreted and used in various ways by different individuals.

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