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In The Photos of the Readers of La Vanguardia we see images of three meteorological phenomena in the same afternoon in Manlleu (Osona). Lightning storm. Sunset as if it were an aurora borealis with rain, causing the appearance of a rainbow.
Summer storms can give rise to these powerful natural electrical discharges of static electricity and offer us a real spectacle of light and sound in the sky, like fireworks.
Lightning is a powerful natural electrical discharge of static electricity, produced during a thunderstorm, which generates an electromagnetic pulse.
The precipitated electric discharge of lightning is accompanied by the emission of light (lightning), caused by the passage of electric current, which ionizes the air molecules, and by the sound of thunder, developed by the shock wave.
Electricity (electrical current), passing through the atmosphere, rapidly heats and expands the air, producing the characteristic noise of thunder.
For its part, a rainbow or rainbow is an optical and meteorological phenomenon that consists of the appearance in the sky of an arc (sometimes two or more) of multicolored light.
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. .
It is caused by the decomposition of sunlight in the visible spectrum, which is produced by refraction, when the sun’s rays pass through small drops of water contained in the earth’s atmosphere.
It is an arc made up of concentric colored arcs, without a solution of continuity between them, with red towards the outside and violet towards the interior.
Less frequent is the double rainbow, which we see in this case in Manlleu, and which includes a second, more subdued arc with the colors inverted, that is, red towards the interior and violet towards the exterior.
Another phenomenon is anticrepuscular rays, which are similar to crepuscular rays, but seen on the opposite side of the sky from the sun.
The anticrepuscular rays are nearly parallel, but appear to converge at the antisolar point, due to linear perspective. They are most often visible at sunrise or sunset.
