SUN - THE SOURCE OF ALL LIFE

Sunlight is energy, which is transferred by means of rays with different wave lengths, whereby we differentiate between ultraviolet rays (ultraviolet light), the visible light, and the warm infrared radiation (IR light). The untraviolet light is divided up into UV-A, UV-B, and UV-C rays. The dangerous UV-C rays are filtered by the athmosphere, and do not reach the surface of the earth. The composition and the strength of the UV-A and UV-B rays vary and depend on the time of day and year, air pollution, degree of altitude, and the intensity of reflection (water, snow, etc.), for example.