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Sometimes two optical effects can be produced at the same time. On this occasion, due to the high clouds, I captured for Las Fotos de los Lectores de La Vanguardia this image with the crown and the solar halo in Calldetenes, Osona region.
The solar halo usually lasts for a long time, while the corona is more ephemeral. The colors of the crown are iridescent, similar to the colors drawn by soap bubbles. They have an intensely bright, almost white center, where all the coronas overlap.
It is an effect that is produced by the diffraction of light and the small drops or ice crystals that are in the fine clouds. For the phenomenon of the solar corona to occur, thin clouds, of the cirrostratus or altostratus type, are necessary.
In the image I was missing an element of spring, which I found in these spiny gorse. It is a small shrub, up to 1 meter tall, characteristic for its thorns. From March to June it shows yellow flowers.
The solar halo forms around the sun presenting an iridescent ring on its outer circumference, due to ice crystals when there are high clouds.
The halo is caused by ice particles suspended in the troposphere that refract light, generating a spectrum of colors around the sun.
