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Four poorly counted drops are what fell yesterday afternoon in Manlleu, in the Osona region, but they left this spectacular sunset that gave us a colorful rainbow, portrayed in La Vanguardia's Readers' Photos.
A rainbow is an optical and meteorological phenomenon that consists of the appearance in the sky of an arc (or two) of multicolored light. In this case, we see it perfectly formed, like a gigantic multicolored bridge that crowns the landscape of Osona after the rain.
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. We can see it in detail in one of the images.
