By LINDA

There might be numerous questions that at one point everyone asks themselves – perhaps when releasing a deep breath while raising our eyes to the heavens or when faltering before the crimson disk of the sun. It is known for a fact that even Leonardo Da Vinci put pen to paper before his death and noted down the question, which he then left unanswered forever: why is the sky blue?

In order to answer this question, one must know the following facts:

The reason why we can see and differentiate between colours is that the wavelength of the light entering our eyes is different. The wavelength of blue light is, for example, very short, while that of red light is long, thus they are located at the extremes of the colour spectrum.

When we look up to the sky, the air mass above us is thinner compared to when we look into the sunset because then light has to travel to our eyes through the thickest possible layer of atmosphere. We see the sky in different colours because of the atmospheric light scattering, without which the sky would be as black as it is at night. At night it is black simply because the photons arriving from the sun do not reach our eyes.

And the process is the following:

When colliding with light, the particles in the atmosphere act as a prism, that is, depending on its wavelength, the particles disperse light around themselves in different angles. The particles in the atmosphere disperse blue photons (that have a short wavelength) much better than they do the sluggish red photons, thus the sky gets painted blue, and we see the proud, living, azure blanket of the firmament shimmering before our eyes whenever we lift our gaze.