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I share in the Photos of the Readers of La Vanguardia this photograph of the rainbow showing off in Arbeca (Les Garrigues) last Sunday. You can see how the green field is illuminated by this colorful phenomenon that appears in the sky.
In recent days there have been many photographs that have been seen of the rainbow showing in different parts of Catalonia, thanks to the return of the desired rains.
A rainbow is an optical and meteorological phenomenon that consists of the appearance in the sky of one arc (or, in this case, two) of multicolored light.
It is caused by the decomposition of sunlight into the visible spectrum, which occurs by refraction, when the sun's rays pass through small droplets of water contained in the Earth's atmosphere.
Although the rainbow is a continuous gradient of spectral colors, it is considered that these can be defined in seven fundamental colors: red, orange, yellow, green, cyan, blue and violet, which are equivalent to those mentioned by the scientist Isaac Newton in 1704. .
Less common is the double rainbow, which includes a second, fainter arc with the colors inverted, that is, red towards the inside and violet towards the outside.
