If you have children, they must have asked you to. “Why is the sky blue?” And there I answered: “Ah … well actually … ah anyway, it’s not time, go brush your teeth and go to bed!”. That’s right, why from the earth do we see it blue, while from the moon we see it black? Like all the remaining space for that matter. Well, it’s all because of the sun.
When the sky lights up, the sky becomes blue. At night, I notice, without the sun, its true color: it is black. Sunlight is light that is said to be white. In fact, it is a mixture of all the colors out there that our eyes see white.
All colors mixed together make white. If you take a disc, draw multi-colored lines on it and rotate it very quickly, you will see only white! When this sunlight passes through the Earth’s atmosphere, it encounters various particles, which will allow some colors to pass through and absorb others.
Like filters. Red, orange, yellow for example, go their way softly. But the blue color, it is preserved by the air molecules that spread it all over the place. That’s why the sky is blue. But when there are clouds, something else happens entirely.
Clouds, as you know, are made of water. And when light passes through a water molecule, it does not interact in the same way that it interacts with an air molecule. Instead of diffusing just blue, the water molecule diffuses all colors of light. And as I told you at the beginning, all of these colors, we perceive … in white. So in real life, if our eyes were sufficiently developed, we would see them in multi-colored clouds. A bit like Care Bears Land.
>> Ah yes? Monday through Friday, Florian Gazan answers in a minute all the basic, existential, and sometimes completely silly questions that come to your mind. Too useful or completely useless knowledge to shine in the community, incredible tales to share, amazing stories to tell. And each time, you’ll say “Oh yeah?” RTL Originals podcast.