Posted on Mar 9, 2022 219
The answer to the question “What color is the Sun, really?” seems obvious - yellow. To be sure of this, it is enough to lift your eyes to the blue sky on a clear day and see a bright yellow circle... But not everything is as simple as it seems at first glance.
The correct color of the sun is white. But the star appears yellow to us because of our planet’s atmosphere. That the white color of the Sun results from the combination of light waves of different lengths. And if you decompose the waves one by one, you get a kind of rainbow - the length of each wave will denote a different color. The shorter the wavelength, the more likely it is that the light wave will bump into a gas molecule in the atmosphere and bounce off in the other direction scatter. But long wavelength colors have no problem bypassing gas molecules and reaching our retina. If you look at the picture below, you can see why we see the Sun more yellow than it really is. The blue and purple colors scatter, and the red and yellow colors reach the surface.
If, however, the Sun is tilting toward sunset, its rays are tangentially directed toward the Earth’s surface, and they need to travel a much greater distance through the atmosphere. The atmosphere will scatter even more light waves, and the most persistent and reddest colors will reach us.
Where does the color of short light waves go? It scatters in the layers of the atmosphere in different directions many times, which is why the sky takes on a blue hue. The higher off the ground, the darker it gets, the fewer gas molecules scattering the light. Now we know why our sky is blue.
But, judging by the picture of wavelengths, violet waves are shorter than blue or blue waves. Why then is our sky not purple? Our eyes, which are much more sensitive to shades of blue than violet, play a big role here. In addition, they scatter most purple rays in the upper layers of the atmosphere.
As you can see from the article, to answer simple, simple questions like “What color is the sun?” or “Why is the sky blue?”, humanity has had to advance far in its knowledge of physics, chemistry, and astronomy. Modern science helps us look at familiar things alternatively that people who lived a few centuries ago didn’t even think about.
This is interesting: traffic lights, emergency lights, and beacons of all kinds do not glow red for nothing. It is this color that is least dispersed in the Earth’s atmosphere.