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In this series of photographs in La Vanguardia Readers’ Photos, captured in Granollers, in the Vallès Oriental, we can observe the confluence of the deformed sun with the condensation trails.

The sun’s rays undergo a bend as they pass through the Earth’s atmosphere. This is an optical phenomenon known as “refraction” and the angle at which light is bent after passing through the Earth’s atmosphere is known as the “angle of refraction.”

Refraction is the change in direction and speed that a wave experiences when passing from one medium to another with a different refractive index. It is also observed very well with respect to the sun when, for example, the so-called Omega effect occurs.

For their part, airplanes form a vapor trail after the kerosene combustion process. The gases expelled by the engine come out at a much higher temperature than the outside temperature.

The sharp contrast in temperatures at a height greater than 30,000 feet (-50 degrees in the atmosphere) causes the immediate condensation of the water present in this mixture of substances. This causes us to see these kinds of elongated ice clouds that dissipate after a few seconds.