How do we see things? Sun looks red during sunset. Why?

How do we see things? Sun looks red during sunset. Why?

We can’t see anything in a dark room but as soon as we open lights we are able to see everything. This is because of reflection of lights, when the beam of light falls on an object get scattered in all directions and when it reaches to our eyes, which we can see the things. Sun looks red during the sunset because the Sunlight has to travel a lot of distance to reach us through the atmosphere, an only colour having high wavelength can reach us that is only Red. And the rest colours of VIBGYOR are missing in a midway because of low wavelength in comparison to Red. That’s how it appears red to us.

Well, our eyes are the just wonderful gift given by God, don’t you think? Its precious and we people, animals, any species all see through eyes. But how?

What makes things visible to our eyes? How does it work? Why can’t we see things in the dark like when we turn off the lights? If these questions are there in your mind then no doubt you are a very intelligent kid.

Why is sun red during sunset and white during mid-day? Is really Sun is red in sunrise and is white in noon or there are some hidden facts behind these colours? I were excited when I started gathering things together to know the real truth and I were also startled and I am sure you will be too. There are some amazing reasons which you should also know.

I have your answers. We will solve this puzzle together taking steps one by one.


How do we see things?

Things can only be seen when lights are there. Yes, if your question is how? Then I have one activity for you. Close all the lights in your room every kind of lights, what do you see? Is there a thing anymore visible to you? No, you can’t see things until you open lights so turn the switch on of lights and see clearly.

Yes, I think I gave you a hint. We all people can see objects only in the presence of lights. When a beam of light falls on an object from its source like tube light, bulb, sun, CFL, then this light get easily reflected (scatter)  in all directions. Then the reflected lights reach our eyes and we become or able to see that object. This process is also called the reflection of lights.

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Here you solved questions. Lights make things visible to our eyes. Things cannot be seen in the dark because of the absence of lights and reflection. Did you notice that? Lights are the main reason why do we see things and the reflection.

Now come to the very next question.

Why is the Sun red during sunset and sunrise?

See sunlight contains 7 colours. Have you ever heard of VIBGYOR or Rainbow colours? Yes, exactly those colours. If we split the sunlight using concave lens or Prism, we will get seven different colours like Violet, Indigo, Blue, Green, Yellow, Orange, and Red exactly in series. Out of these colours, Violet has the lowest wavelength 400-440 and Red has the highest 620-720.

In the morning or evening, the Sunlight has to travel a lot of distance to reach us through the atmosphere. So, when the sunlight is traveling more distance through the atmosphere of the earth to us, an only colour having high wavelength can reach us that is only Red. And the rest colours are missing in a midway because of low wavelength in comparison to Red.

That’s the reason why Sun appears red both the times in the morning and the evening.

If it’s like that then why Sun appears white in the daytime or noontime?  Why not any other colours from VIBGYOR? Well, quite interesting, isn’t it? So let it be our very next question.

Why Sun appears to be white at daytime?

Have you ever noticed when its noon time the sun is just above our head? Like this picture, the sun is just at our overhead at the noon. In this case, Sun has to travel a very shorter distance to reach us through the atmosphere in comparison to sunset or sunrise time. During this journey, only a little of the blue colour of white light is scattered.   In this situation light is coming directly from overhead, the sun has its entire colour in the right proportion, therefore, it appears white.

More clearly, at noontime, the sun is just above our head say 12.00pm to 3.00pm, it’s at the top so the distance it has to cover to pass lights to us is very short or you can say it has to travel a shorter distance, not like sunrise or sunset time. Sun is at the nearest point to the earth. So all the colours get scattered very less even blue and it appears to us white. All the colours get scattered almost equally that’s why it appears white.

I hope you get that and now the point is clear to you. Everything here has to do with distance covered by Sun and the scattering of colours.

So, like me, you also know the reasons behind this white colour of Sun at midday and red colour at sunrise and sunset time. Its great nature has many things to show us and has scientific logic behind everything.

Now you know the real reason behind this changing colour of the sun and how do we see the things.

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