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I am sharing this photograph of the rainbow this afternoon on the beach of Gavà Mar, in the Baix Llobregat, in Las Fotos de los Lectores de La Vanguardia.

Images like this are a reason for hope, since this phenomenon has occurred after a period of much-needed rain. And, after it rained, the sun came out again giving way to this beautiful rainbow over the Mediterranean Sea.

A rainbow is an optical and meteorological phenomenon that consists of the appearance of a multicolored arc of light in the sky. In this case, we do not see it in its entirety, but only a part that looks like a multicolored lightning bolt that emerges from the clouds and reaches the horizon line in the sea.

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. .