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In this photograph in La Vanguardia Readers' Photos we can literally see how a rainbow emerges from the sea on the Costa Brava, rises above the road and is lost among the clouds.
The latest rainfall in Catalonia, breaking the trend of drought in the province of Girona, has revealed this meteorological phenomenon.
Furthermore, in this case, it is double. Less frequent and more unlikely to see, it includes a second, fainter arch with the colors inverted, that is, red towards the inside and violet towards the outside.
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. .
