* The author is part of the community of readers of La Vanguardia
This morning the presence of medium clouds with slits shortly after sunrise has provided us in Barcelona with a beautiful spectacle of crepuscular rays, as can be seen in this series of photographs in Las Fotos de los Lectores de La Vanguardia.
Crepuscular rays, in atmospheric optics, are rays of sunlight that appear to radiate from a single point in the sky. We see in these images how they are projected over the city of Barcelona.
These rays flow through openings in clouds (mostly stratocumulus) or between other objects. They are columns of sunlit air separated by dark cloud shadow regions.
The name comes from its frequent appearances during the twilight hours (sunrise and sunset), when the contrasts between light and dark are most obvious.
It is not for nothing that crepuscular comes from the Latin word crepusculum which means "twilight". The photographs have been captured from the Observatori Fabra, a splendid privileged observation point in the city of Barcelona. It is located on a buttress of the Tibidabo mountain, facing south, 415 meters above sea level.
