Green ray: what is it and why are they "hunting" for this phenomenon?

A green ray is an optical phenomenon that can be seen shortly after sunset or before sunrise. This happens when the Sun is almost completely below the horizon, and its upper edge is still visible. It turns green for a second or two. Some fans of interesting natural phenomena even "hunt" for such moments.

Legends have even arisen around the phenomenon. For example, some people say that once they see a green ray, a person will never make mistakes in "matters of the heart" again. And Jules Verne has a novel of the same name, which is based on the Scottish legend of the green ray, which gives happiness to those who saw it.

To see this phenomenon, two conditions are necessary: a clear day without haze and clouds, as well as a distant, clearly visible horizon. Most often, a green flash is seen over the ocean, but you can "catch" it even being on top of a mountain or a tall building.

Important advice: do not look at the Sun until it is almost completely hidden below the horizon. Otherwise, you may injure your eyes.

Why does the green ray appear?

When the sun's rays are refracted in the atmosphere, they decompose into a spectrum, the refractive power depends on the wavelength of the beam. The decomposition into the spectrum is most pronounced precisely at the moment of sunset — when only the upper part of it can be seen above the horizon, which, among other things, due to the overlapping of color rays becomes blue-green (the lower one is orange-red).

The last ray of the sun decomposes into a spectrum and forms several rays — although we should see purple with the last ray, due to the fact that this is a short-wave ray (like blue and cyan), it is scattered in the atmosphere, so we see emerald last.