The sun produces light with a distribution similar to what would be expected from a 5525 K (5250 °C) black-body, which is approximately the suns surface temperature. Radiation interacts with matter in several ways: Absorption, Transmission, Scattering, Reflection. When a photon is absorbed, its energy is changed into a different form: electrical or heat. A fraction of the incoming solar radiation is reflected back into space - this is known as the albedo. Direct normal solar radiation is the part of sunlight that comes directly from the sun. This would exclude diffuse radiation, such as that...