Un halo est un phénomène optique apparaissant, à certaines conditions, dans le ciel autour du Soleil
▪ Description:
There are many types of ice halos. They are produced by the ice crystals in cirrus clouds high (5–10 km, or 3–6 miles) in the upper troposphere. The particular shape and orientation of the crystals is responsible for the type of halo observed. Light is reflected and refracted by the ice crystals and may split up into colors because of dispersion. The crystals behave like prisms and mirrors, refracting and reflecting sunlight between their faces, sending shafts of light in particular directions.
Source: http://en.wikipedia.org/wiki/Halo_(optical_phenomenon)
There are many types of ice halos. They are produced by the ice crystals in cirrus clouds high (5–10 km, or 3–6 miles) in the upper troposphere. The particular shape and orientation of the crystals is responsible for the type of halo observed. Light is reflected and refracted by the ice crystals and may split up into colors because of dispersion. The crystals behave like prisms and mirrors, refracting and reflecting sunlight between their faces, sending shafts of light in particular directions.
Source: http://en.wikipedia.org/wiki/Halo_(optical_phenomenon)
avril 2003 St-Martin St-Barthélemy
Album mis à jour le lundi, 26 décembre 2016, 19 h 29
